# Mapping Observations of Peptide-like molecules around Sagittarius
B2111Released on March, 1st, 2021

Siqi Zheng  Shanghai Astronomical Observatory, Chinese Academy of Sciences
No. 80 Nandan Road
Shanghai, 200030, China  Key Laboratory of Radio Astronomy, Chinese Academy of
Sciences
Nanjing 210033, China  School of Astronomy and Space Sciences, University of
Chinese Academy of Sciences
No. 19A Yuquan Road
Beijing 100049, People’s Republic of China  Juan Li  Shanghai Astronomical
Observatory, Chinese Academy of Sciences
No. 80 Nandan Road
Shanghai, 200030, China  Key Laboratory of Radio Astronomy, Chinese Academy of
Sciences
Nanjing 210033, China  Junzhi Wang  Guangxi Key Laboratory for Relativistic
Astrophysics, Department of Physics, Guangxi University
Nanning 530004, PR China  Yao Wang  Purple Mountain Observatory, Chinese
Academy of Sciences, 10 Yuanhua Road, Nanjing 210023, People’s Republic of
China  Feng Gao  Hamburger Sternwarte, Universität Hamburg
Gojenbergsweg 112, D-21029, Hamburg, Germany  Max Planck Institute for
Extraterrestrial Physics (MPE), Giessenbachstr. 1, D-85748 Garching, Germany
Donghui Quan  Xinjiang Astronomical Observatory, Chinese Academy of Sciences,
150 Science 1-Street, Urumqi 830011, People’s Republic of China
Research Center for Intelligent Computing Platforms, Zhejiang Laboratory,
Hangzhou 311100, China  Fujun Du  Purple Mountain Observatory, Chinese Academy
of Sciences, 10 Yuanhua Road, Nanjing 210023, People’s Republic of China
School of Astronomy and Space Science, University of Science and Technology of
China, Hefei 230026, People’s Republic of China  Yajun Wu  Shanghai
Astronomical Observatory, Chinese Academy of Sciences
No. 80 Nandan Road
Shanghai, 200030, China  Key Laboratory of Radio Astronomy, Chinese Academy of
Sciences
Nanjing 210033, China  Edwin Bergin  Department of Astronomy, University of
Michigan, Ann Arbor, MI 48109, USA  Yuqiang Li  Shanghai Astronomical
Observatory, Chinese Academy of Sciences
No. 80 Nandan Road
Shanghai, 200030, China  Key Laboratory of Radio Astronomy, Chinese Academy of
Sciences
Nanjing 210033, China  School of Astronomy and Space Sciences, University of
Chinese Academy of Sciences
No. 19A Yuquan Road
Beijing 100049, People’s Republic of China

###### Abstract

Peptide-like molecule, which has a close connection with the origin of life,
has been detected in universe. Mapping observations of HCONH2 and CH3CONH2,
two simplest peptide-like molecules, are performed towards Sagittarius B2 (Sgr
B2) complex with the IRAM 30m telescope. Seven transitions of HCONH2 and five
transitions of CH3CONH2 are used in analysis. The spatial distribution of
excitation temperature and column density of HCONH2 in the molecular envelope
of Sgr B2 are obtained by the rotation diagrams. Assuming the same excitation
temperature as HCONH2, the column densities of CH3CONH2 are also calculated.
The results show that excitation temperature ranges from 6 K to 46 K in the
molecular envelope of Sgr B2. The abundance ratio between HCONH2 and CH3CONH2
are calculated to explore the relationship among them, as well as HNCO
mentioned in our pervious research. The abundance ratio of CH3CONH2/HCONH2
varies from 10% to 20%, while that of HCONH2/HNCO ranges from 1.5% to 10%.
CH3CONH2 is enhanced with respect to HCONH2 in the northwest region of Sgr B2.
One transition of H13CONH2 is detected toward 12 positions of Sgr B2, from
which a ${}^{12}C$/${}^{13}C$ ratio of 28.7 is obtained. A time-dependent
chemical model with a short duration of X-ray burst is used to explain the
observed abundances of HCONH2 and CH3CONH2, with the best fitting result at
$T_{\mathrm{dust}}$ = 53-56 K. More chemical reactions are required to be
included into the model since the modeled abundance is lower than the observed
one at the observed $T_{\mathrm{dust}}$.

Interstellar molecules — Abundance ratios — Isotopic abundances — Molecular
clouds

††thanks: E-mail<EMAIL_ADDRESS>E-mail:
<EMAIL_ADDRESS>E-mail<EMAIL_ADDRESS>
##  1 Introduction

Peptide bond [-NH-C(O)-] is the element that links two amino acids together to
form proteins. As a result, peptide-like molecules, the molecules with a
structure like the peptide bond, can give us some hints into the origin of
life in universe. Formamide (HCONH2) and acetamide (CH3CONH2) are the smallest
two peptide-like molecules. HCONH2 has been detected in many high-mass star
formation regions, comets, low-mass star formation regions and translucent
cloud (e.g. López-Sepulcre et al., 2015; Colzi et al., 2021). It is regarded
as the precursor of many other prebiotic molecules (Saladino et al., 2012).
CH3CONH2 has been detected in high-mass star formation regions (e.g. Hollis et
al., 2006; Halfen et al., 2011; Colzi et al., 2021), intermediate-mass
protostar Serpens SMM1-a (Ligterink et al., 2022), and tentatively detected in
low-mass protostar IRAS 16293-2422 (Ligterink et al., 2018). CH3CONH2 was only
detected toward several sources, which was much less detected than that of
HCONH2.

Many chemical models have been proposed based on experiments and theoretical
calculations to explain their abundance observed in ISM, including gas-phase
reactions and grain surface reactions. The formation of HCONH2 is still under
discussion (see López-Sepulcre et al. (2019) for detail). Barone et al. (2015)
suggested that H2CO + NH2 $\longrightarrow$ HCONH2 \+ H was an effective way
for HCONH2 to form in gas-phase reaction according to the results of their
electronic structure and kinetice calculation. Skouteris et al. (2017)
calculated the deuteration rate of HCONH2 in this reaction. The results of
computations were in good agreement with the observation in the hot corino of
IRAS16293-2422 B. This reaction has also been used to explain the observed
spatial segregtion of HCONH2 with respect to other species in shock region
L1157-B1 by Codella et al. (2017). A newly proposed grain surface reaction is
the reaction between CN radial and the water molecule of the ice mantle
(Rimola et al., 2018). The hydrogenation of HNCO was ruled out by experiments
(Noble et al., 2015), but Haupa et al. (2019) proposed a model that link HNCO
and HCONH2 with a double-cycle based on their experiment results. For
CH3CONH2, many gas-phase reactions and grain-surface reactions have also been
proposed (e.g. Quan & Herbst, 2007; Quénard et al., 2018). A constant ratio
between HCONH2 and CH3CONH2 in various physical environments indicates that
they form at an early state of star formation on the interstellar dust grains
(Ligterink et al., 2022). Which kind of reactions are most important for
reproducing the abundance of CH3CONH2 and HCONH2 in different environment need
to be constrained by more observation results.

Sagittarius B2 (hereafter Sgr B2) is an ideal place to study the chemical
origin and the relationship between HCONH2 and CH3CONH2, where many complex
molecules have been detected to have an extended distribution and strong
emission there (e.g. Jones et al., 2008; Li et al., 2017). It consists of
three parts: a low density envelop, a moderate density region and molecular
hotspots where the high-mass stars are forming (Hüttemeister et al., 1993).
The two major high-mass star formation regions with high chemical richness are
called Sgr B2(N) and Sgr B2(M). Both HCONH2 and CH3CONH2 have been detected in
Sgr B2(N) (Hollis et al., 2006; Halfen et al., 2011). Later, in the hot cores
of it, such as Sgr B2 (N1), Sgr B2 (N2), Sgr B2 (N3), Sgr B2(N4) and Sgr
B2(N5), these two molecules has also been detected and analysed (e.g. Bonfand
et al., 2017; Belloche et al., 2019; Li et al., 2021). For Sgr B2(M), only
HCONH2 has been detected, while CH3CONH2 has not been detected (Belloche et
al., 2013). The molecular envelop has an average H2 density of $\sim$ 103
cm-3, and H2 column density of $\sim$ 1023 cm-2 (Goldsmith et al., 1990). The
size of it is 38 pc (15.4 ′) in diameter (Scoville et al., 1975). The spatial
distribution of different molecules here was found to be significantly
different (e.g. Jones et al., 2008, 2011). In the molecular envelop of Sgr B2,
G+0.693-0.27 (hereafter G+0.693) is a quiescent giant molecular cloud with
great interest. This is a source with low excitation temperature and high
levels of chemical richness (Requena-Torres et al., 2008; Zeng et al., 2018),
while there is no sign of active star formation (Zeng et al., 2020). Recently,
Zeng et al. (2023) detected both molecules in G+0.693. While the observation
towards the hot cores and cold envelop of Sgr B2 are carried out, all of the
observations mentioned above are performed toward a single position. The
simultaneous mapping observation of both molecules can not only avoid the
uncertainties introduced by absolute flux calibration and pointing, but also
tell us how the abundance ratio varies with the environment. The spatial
variation of the abundance ratio indicates the possible mechanisms that
dominate the chemical networks. Besides, the physical conditions of the
extended molecular envelope of Sgr B2, which remain unclear now, could be
obtained with multiple transitions of these molecules.

In this paper, we present mapping observation results of HCONH2 and CH3CONH2
with the IRAM 30m toward Sgr B2 complex. We study the spatial distribution and
the abundance ratio of HCONH2 and CH3CONH2 in Sgr B2, and the possible
chemical paths would be proposed according to the abundance ratio. In Section
2, we introduce the observation and data reduction. In Section 3, we present
the results of our observation. In Section 4, we make a scientific discussion
about the results. The conclusions are summarised in Section 5.

##  2 Observation and data reduction

We have performed mapping observation toward Sgr B2 with the IRAM 30m
telescope on Pico Veleta Spain (project 170-18) in 2019 May. The Eight MIxer
Receiver and FFTs in FTS200 mode were used in position-switching mode. The
observation were performed at the 3 mm band, covering a frequency range of
82.3-90 GHz. The channel spacing is 0.195 MHz, which corresponds to the
velocity resolution of 0.64 km s-1 at 84 GHz. Pointing was checked every
$\sim$2 h on 1757-240, and the focus was calibrated on 1757-240 before the
observation. The integration time ranges from 24 minutes to 98 minutes for
different positions, with a typical system temperature of $\sim$110 K, which
gives a 1$\sigma$ rms of 4-8 mK in $T_{\rm A}^{\ast}$ derived with the line
free channels. The calibration uncertainty is within 20%.

The observing center is Sgr B2(N)
($\alpha_{J2000}=17^{h}47^{m}20^{s}.0$,$\delta_{J2000}=-28^{\circ}22\arcmin
19.0\arcsec$), with a sampling interval of 30″and a beam size of 30″. The off
position of ($\delta\alpha$, $\delta\beta$)=(-752″, 342″) with respect to Sgr
B2(N) was used (Belloche et al., 2013). The data were reduced with CLASS
software222http://www.iram.fr/IRAMFR/GILDAS.. The continuum emission was
substracted via first-order polynomial fitting. The antenna temperature
($T_{\rm A}^{\ast}$) was transformed into the main beam brightness temperature
($T_{\rm mb}$) using $T_{\rm mb}$=$T_{\rm A}^{\ast}\cdot F_{\rm eff}/B_{\rm
eff}$, where the forward efficiency $F_{\rm eff}$ is 0.95 at 3 mm, and the
beam efficiency $B_{\rm eff}$ is attained using Ruze’s equation. The spectra
are smoothed to 1.35 km s-1 to improve the signal-to-noise ratio.

##  3 Results

63 positions of Sgr B2 are observed to make the spatial distribution maps of
target molecules. Due to the strong continuum and complex environment in Sgr
B2(N) and Sgr B2(M), it would be difficult to do baseline correction and to
separate the absorption or emission that comes from hot cores or the cold
envelope. Therefore, the spectra of molecules in both Sgr B2(N) and Sgr B2(M)
are not considered in the further analysis. Among the transitions of HCONH2
and CH3CONH2, the transitions with high upper state energies are only detected
around the hot cores, while in the cold envelope only transitions with low
upper state energies ($E_{u}<$ 40 K) can be detected. Besides, many
transitions of the target molecules are blended with the transitions of other
species due to the large line width of spectra in Sgr B2 (e.g. Belloche et
al., 2013). Finally, seven transitions of HCONH2 and five transitions of
CH3CONH2 are selected because their emission is clean and strong enough to be
detected in the cold envelop. One transition of H13CONH2 are also used for
analysis. The information of these transitions is listed in Table 1. The
spectroscopic entries from Cologne Database for Molecular Spectroscopy (Müller
et al., 2005) are used. The transition data of CH3CONH2 was provided by
Ilyushin et al. (2004).

###  3.1 HCONH2

####  3.1.1 Distribution of HCONH2

The emission of HCONH2 11,1-00,0, 40,4-30,3, 42,3-32,2, 42,2-32,1 and
41,3-31,2 are observed to be stronger than 3 $\sigma$ in 60, 63, 59, 60 and 63
positions with 1 $\sigma$ of about 0.01 K in Tmb, respectively. The emission
of HCONH2 43,2-33,1 and 43,1-33,0 are observed to be weaker than other
observed transitions of HCONH2, which have the emission stronger than 3
$\sigma$ in 32 positions. The frequencies of these two transitions are very
similar, with a difference of 2 MHz. As a result, these two transitions
blended with each other, and will be solved together. The detection threshold
for all transitions is 3 sigma. HCONH2 11,1-00,0 is partially blended with
C2H5CN,v=1, but can be separated from each other in the spectra. This is also
the only one b-type transition ($\Delta K_{a}=\Delta K_{c}=\pm 1$), while
others are a-type transitions ($\Delta K_{a}=0$). Since the profiles of the
spectra in Sgr B2 are complex (e.g. Belloche et al., 2013), which can not be
fitted with a single gaussian component, the integrated intensities over a
certain velocity range would be used in the following works. The integrated
intensities, the first moment (the intensity-weighted velocity) and the second
moment (the intensity-weighted velocity dispersion) of the transitions in
different positions are listed in Table A1 and Table A2. The integrated
intensity maps of each transition are shown in Figure 1 in order of increasing
upper state energies. The intensities where the emission is lower than 3
$\sigma$ (1 $\sigma\sim$ 0.07 km s-1 K) are assumed to be 0. Sgr B2(N)
(including Sgr B2(N1), Sgr B2(N2) and so on), Sgr B2(M) and G+0.693, where
HCONH2 has been detected, are labeled with ${}^{\prime\prime}\times"$. Because
the sampling does not satisfied the Nyquist sampling criterion, the emission
sizes and peak positions for different transitions are decided by eyes, which
are listed in Table 2. The equivalent radius of the area where the emission is
stronger than half of the emission at the peak position is used to describe
the emission size.

According to Table 2 and Figure 1, the emissions of different transitions are
extended in Sgr B2, while the emission size decreases with the increasing
upper state energies. The shift in peak position of different transitions is
significant comparing with the angular resolution of observations. The spectra
of the observed transitions of HCONH2 near the peak positions: Sgr B2(N) and
position (30″, 60″) are displayed in Figure 2, with blue dashed lines to show
the LSR velocity. The LSR velocity in each position is determined with the
line profile of H13CCCN 10-9 in our data, considering its relatively strong
emission and low optical depth. For transition with a small upper state
energy, corresponding to HCONH2 11,1-00,0, the emission has the largest
emission size, and peaks at the north cloud of Sgr B2, near position (30″,
60″). G+0.693 is located in projection 0.32 pc (or 8″) south of the position
(30″, 60″), with a LSR velocity of 68 km s-1 (Requena-Torres et al., 2006) and
a typical lines FWHM of about 20 km s-1 (Zeng et al., 2018). The observed
spectra in position (30″, 60″) (see Figure 2) have a good agreement with this
LSR velocity and linewidth. It has been suggested that there are large-scale,
low velocity shocks (Henshaw et al., 2016; Zeng et al., 2020). Many molecules
have been found to be enhanced there, such as HNCO, HCO${}_{2}^{+}$ and CH3OH
(e.g. Minh et al., 1998; Jones et al., 2008). The low velocity shocks in
G+0.693 might be a possible explanation for the emission peak there. When the
upper state energy increases, such as HCONH2 40,4-30,3 and 41,3-31,2, the peak
moves to the west of Sgr B2(M), near position (-30″, -60″). The equivalent
radius of emission region is $\sim$ 55″for these two transitions. If the upper
state energy is higher, like HCONH2 42,3-32,2, 42,2-32,1, HCONH2 43,2-33,1 and
43,1-33,0, the emission has the smaller emission size than other transitions,
and peaks near Sgr B2(N). Sgr B2(N) is a source with many complex organic
molecules (COMs) detected to have high column density and high excitation
temperture, Most of the molecules there emit in the LSR velocity of $\sim$
63-64 km s-1 and 73-74 km s-1, with a linewidth of 7 km s-1 for each velocity
component(Belloche et al., 2013). This is consistent with the spectra in
Figure 2. Similar variation between the distribuion of different transitions
has been mentioned by Jones et al. (2008) and Jones et al. (2011). Such
variation among different transitions reflects the complex excitation
environment there, which would be analysed by rotation diagrams in Section
3.1.3.

####  3.1.2 isotopic species

The emission of H13CONH2 404-303 is also detected in the observation as listed
in Table 1. In addition to Sgr B2(N), H13CONH2 404-303 has an emission
stronger than 3 $\sigma$ in 11 positions. The spectra are shown in Figure 3,
with the spectra of HCONH2 404-303 as a comparison to investigate whether this
transition is optically thick. The spectra of HCONH2 404-303 are divided by
25, 20, 15 and 3 to compare with the spectra of H13CONH2 in different
positions. The 12C/13C ratio can also be obtained from those two transitions.
The integrated intensity map is drawn to find out its spatial distribution
(see Figure 4). The distribution of H13CONH2 404-303 in the extended envelope
is found to have a similar morphology with that of HCONH2 404-303. In
comparison, the emission of H13CONH2 404-303 peaks in Sgr B2(N) while that of
HCONH2 404-303 is weak, impling the emission around there is optically thick.

With the emission of isotope spieces detected in multiple positions, the
isotope ratio 12C/13C in the region can be obtained from the intensity ratio
of H13CONH2 and HCONH2 404-303. Here we assume that the abundance ratio of
HCONH2 to H13CONH2 has the same values as the intensity ratio, considering
their similar upper state energies ($E_{u}$). Another assumption is that the
ratio of 12C to 13C is equal to the abundance ratio of HCONH2 and H13CONH2,
namely, there is no isotope fraction. The isotope ratio is assumed to be a
constant value in Sgr B2. Based on these assumptions, the intensity ratio
between HCONH2 and H13CONH2 is equal to the ratio of 12C to 13C if the
transitions used are optically thin. In Table 3, the intensity ratios of
HCONH2 404-303 to H13CONH2 404-303 in the positions where H13CONH2 404-303 is
detected are listed. Since HCONH2 404-303 is probably opically thick, a larger
intensity ratio and the intensity ratio in the positions with large distance
from hot cores can reflect the isotope ratio better. Therefore, position (0″,
-60″) and (0″, 0″) are excluded when analysing the isotope ratio. Position
(0″, 90″) is also excluded because of its extremely large intensity ratio.

The ratio of 12C/13C obtained from the intensity ratio is about 26 to 33,
indicating the assumption of a constant ratio in the envelope of Sgr B2 is
reasonable. To obtain the 12C/13C ratio of the envelope, the emission of
H13CONH2 404-303 in the region far away from the hot cores are averaged. After
averaging the spectra, the signal-to-noise ratio raises and the emission of
H13CONH2 can than be detected to be stronger than 3 $\sigma$ (1 $\sigma$ = 1.8
mK) in the region shown within the blue square frame in Figure 4. The averaged
spectra of HCONH2 404-303 and H13CONH2 404-303 are shown in Figure 5. The
spectra are integrated in the same velocity range which is marked with red
window in the figure. The ratio between the intensities of these two lines is
28.7 $\pm$ 1.7 (listed in the last line of Table 3), within the uncertainty of
the result calculated from single position, which can be regarded as the
12C/13C ratio of the envelope.

The opical depths ($\tau$) of HCONH2 404-303 can then be calculated from the
isotope ratio according to the following formula:

$\frac{I_{\mathrm{HCONH_{2}}}}{I_{\mathrm{H^{13}CONH_{2}}}}=\frac{1-exp(-\tau)}{1-exp(\frac{\tau}{{}^{12}C/^{13}C})}$
(1)

. where $I_{\mathrm{HCONH_{2}}}$ and $I_{\mathrm{H^{13}CONH_{2}}}$ are the
integrated intensities of HCONH2 404-303 and H13CONH2 404-303. The results are
listed in the last column of Table 3. In the envelope of Sgr B2, only the
emission in position (0″, -60″) has a relatively large $\tau$ of 0.51. For the
other positions, the emission is opically thin. The much smaller ratio in
position (0″, 0″), where Sgr B2(N) is located, gives a large $\tau$ of 5.30.
Part of the emission there comes from the hot cores, which is difficult to be
separated from the component of the envelope around. The strong continuum and
high molecular abundance of the hot core may be a reason accounting for such
larger $\tau$. Due to its complexity, we would not put emphasis on this
position and may pay more attention to the positions in the cold extended
envelope (further discussion in Section 4.1).

####  3.1.3 Rotation diagram

As seven transitions of HCONH2 have been detected in most of the regions in
Sgr B2, the column densities and excitation temperature of HCONH2 toward
different positions can be attained with rotation diagrams. The intensities of
transition HCONH2 40,4-30,3 are corrected with the optical depth obtained from
the 12C/13C. The other transitions are regarded to be opically thin under the
LTE assumption, and a single temperature could be used to describe the energy
level populations in the area.

The transitions that are lower than 3 $\sigma$ levels would not be used in
fitting, but they would be labeled in the diagrams with an arrow to represent
their 3 $\sigma$ upper limits. Rotation diagrams can be drawn according to the
formula (Herbst & van Dishoeck, 2009):

$\frac{N_{u}}{g_{u}}=\frac{N_{tot}}{Q(T_{rot})}e^{-\frac{E_{u}}{T_{rot}}}=\frac{8\pi
k\upsilon^{2}I}{hc^{3}A_{ul}g_{u}}$ (2)

where Nu is the column density of upper energy level, gu is the upper state
degeneracy, Ntot is the total column density, Trot is the rotation
temperature, Q(Trot) is the partition function, Eu is the upper state energy,
I is the intensity, c is the velocity of light, and Aul is the emission
coefficient. Trot is equal to excitation temperature (Tex) under the LTE
assumption. Q(Trot) is the function of Trot, calculated by the formula:
$Q(T_{rot})=\sum g_{i}e^{E_{i}/kT_{rot}}$. The calibration error is not
included into the error of intensities because the calibration error is small
enough to be obmitted after averaging the spectra of each scan. Since the
emission is more extended than the telescope beam according to the
distribution map of different transitions, a filling factor correction is not
considered.

The transition HCONH2 11,1-00,0 is not included in all of the diagrams because
it deviated too much from the fitted straight line in the rotation diagram of
every position. This deviation can be the result of its different transition
type from other lines, which is a b-type transition. It is likely that the
a-type transitions and b-type transitions of HCONH2 is not thermalized there.
If the point of the b-type transition is located near the fitting line, the
intensity of it in each position needs to be about 10 times weaker that what
it is now. Therefore, the column density obtained from the b-type transition
would be one magnitude larger than that obtained from a-type transitions. This
phenomenon has also been observated by Nummelin et al. (2000) and Zeng et al.
(2018). Because the transitions of a-type and b-type couple together, namely
both type of transitions can be produced from the same upper energy level, we
regard the a-type and b-type as two different temperature components of
HCONH2. For position (30″, 60″), the excitation temperature of b-type
transitions in G+0.693, which is 3.7 $\pm$ 0.7 K(Zeng et al., 2018), can be
used to calculate the column density of b-type transition there. The obtained
column density of b-type transition there is 1.14 $\pm$ 0.23 $\times
10^{15}cm^{-2}$. The column density of a-type transitions derived from the
rotation diagram is 1.3 $\pm$ 0.3 $\times 10^{14}cm^{-2}$ with an excitation
temperature of 13.1 $\pm$ 3.0 K. The total column density in this position is
1.27 $\pm$ 0.26 $\times 10^{15}cm^{-2}$ taking into account both a-type and
b-type transitions. The ratio of b-type to a-type transitons is 8.8. For other
positions, only one b-type transition is detected. The rotation diagram is not
available to deal with both types of the transition separately. So, we only
give the column densities of HCONH2 with a-type transitions. The significant
difference betwween the excitation temperature and column density of both type
transitions perhaps suggests that transitions with different types trace
different physical regions.

In some positions, such as Sgr B2(N) and Sgr B2(M), there is absorption and
seriously blending from other molecules. Therefore, these positions are not
used to draw the rotation diagram. In addition, position (90″, 120″) and (90″,
90″) are also not used as these two positions would produce fake information
in the distribution map. Position (30″, 150″), (-120″, -30″) and (-120″, -60″)
are not used as well due to the low intensities of more than 2 transitions.

Only 54 positions are used to draw the rotation diagrams. The selected
positions are shown with green ${}^{\prime\prime}\times"$ in Figure 6. The
rotation diagrams are shown in Figure A1 and Figure A2, corresponding to the
positions with HCONH2 43-32 detected and not detected. Since HCONH2 11,1-00,0
is not included in the fit, it is labeled as an orange square, while other
transitions are labeled as blue circles. From the results of ratotation
diagrams, the distribution of column densities and excitation temperature
could be obtained. The results are shown in Figure 7 and Table 4. The values
at the positions not labeled in Figure 6 are interpolated from the values
around them, which do not have physical meanings. According to the figure, the
$\rm T_{ex}$ of HCONH2 range from 6 K to 46 K, with higher values around the
hot cores. The column densities of HCONH2 calculated with only a-type
transitions range from 0.2 to 4.6 $\times 10^{14}cm^{-2}$. More details about
the rotation diagrams are discussed in section 4.2.

###  3.2 CH3CONH2

####  3.2.1 distribution

Because of the internal rotation of methyl group, CH3CONH2 has A- and E-
species. In our observations, only CH3CONH2-A has relatively clean and strong
emission. The frequencies of the used CH3CONH2-A transitions are similar, with
a difference of 2.7 MHz ($\sim$ 9.3 $km$ $s^{-1}$, a smaller line width than
the typical line width in Sgr B2). Therefore, those transitions will also be
used together. The column densities for all positions are measured with the
emission of CH3CONH2-A. The transitions of CH3CONH2-A are observed to be
stronger than 3 $\sigma$ in 30 positions. The spectra of CH2CONH2 in all the
positions with emission stronger than 3 $\sigma$ levels are shown in Figure 8,
with the spectra of HCONH2 422-321 overlapped on them. The dashed blue lines
are used to show the LSR velocity of the position. In the extended cold
envelope, the profiles of the spectra of HCONH2 and CH3CONH2 were similar to
each other in the same position, from which we can assume these transitions
were excited from the same cloud.

The integrated intensity map of CH3CONH2 is shown in Figure 9. All the
transitions of CH3CONH2-A listed in Table 1 are used to draw the map. The
intensities are assumed to be 0 in the positions where the emission is lower
than 3 $\sigma$ levels. The emission size and the peak position are listed in
Table 2. The transitions of CH3CONH2 have similar emission sizes as that of
HCONH2 40,4-30,3, while it peaks near Sgr B2(N). The distribution of emission
in the envelope of Sgr B2 is similar to the transitions of HCONH2, which may
imply that these two molecules are chemically or physically linked.

####  3.2.2 Column density

As the detected clean transitions of CH3CONH2 blend with each other, the
column densities and excitation temperature can not be obtained by rotation
diagrams. As a results, the column densities are calculated using the detected
transitions together, assuming the same excitation temperature as HCONH2.

Since the difference between the upper state energies of different transitions
is small, which is 19.82 K and 18.77 K for 8-7 A and 7-6 A respectively, they
have a similar sensitivity to the excitation temperature. Namely, the column
densities calculated from these transitions will not deviate too much if we
assume they have the same upper state energy. Thus, a common upper state
energy is used to simplify the calculation. Because the transitions CH3CONH2
8-7 A have larger dipole moment (see in Table 1), the emission of them would
be stronger than that of CH3CONH2 7-6 A. Most of the error is also generated
by transitions CH3CONH2 8-7 A. Therefore, the upper state energy of CH3CONH2
8-7 A (19.82 K) is chosen as the upper state energy to avoid the complexity of
calculation. The column densities are calculated with the following formula
(Pillai et al., 2007):

$N_{tot}=\frac{N_{u}}{g_{u}}\times Q(T_{ex})\times
exp(E_{u}/kT_{ex})=\frac{3h}{8\pi^{3}S\mu^{2}}\times\frac{I\times
Q(T_{ex})}{J_{\nu}(T_{ex})-J_{\nu}(T_{bg})}\times\frac{J(T_{ex})}{\eta_{\nu}}$
(3)

where Eu is the upper state energy, $\mu^{2}$ is the dipole moment, and S is
the line strength. The value of $\mu^{2}S$ is obtained from the sum of each
transition. $\eta_{\nu}$ is the beam filling factor, which is set to be 1
because the emission of $\rm CH_{3}CONH_{2}$ is extended.

The results are listed in Table 4. For the position where the emission of
CH3CONH2 is not detected, the upper limits of column densities is given. The
column densities of CH3CONH2 range from 0.6 to 7.6 $\times 10^{13}cm^{-2}$.
The distribution of column density is shown in Figure 10, with the
distribution map of the column densities of HCONH2 as comparison. The column
densities where CH3CONH2 are not detected are set to be 0. According to the
figure, the distributions of both molecules have an extended distribution and
increase rapidly around hot cores. The abundance ratio with respect to HCONH2
is discussed in section 4.3.

##  4 Discussion

###  4.1 isotopic species

From the intensity ratio of HCONH2 to H13CONH2 (in Table 3), the derived ratio
of 12C to 13C is 28.7 $\pm$ 1.7 in Sgr B2. This ratio is consistent with
previous researches which obtain a ratio of 25 $\pm$ 8 and 31 $\pm$ 8 from the
two components of HCONH2 in Sgr B2(N) (Halfen et al., 2017), and the average
ratio of 24 $\pm$ 7 and 23 $\pm$ 6 obtained from the two components of 7
different molecules in Sgr B2(N), but slightly higher than the raito of $\sim$
25 obtained from CH3OH in Sgr B2 (N2) (Müller et al., 2016).

However, this ratio is just the ratio obtained from the region in the west of
Sgr B2. The emission of H13CONH2 404-303 is too weak to be detected in the
averaged spectra in other regions of Sgr B2. More observations are required to
do a further study about the 12C/13C ratio in the envelope of Sgr B2.

###  4.2 rotation diagram

With the rotation diagrams of HCONH2, the excitation temperature in the
envelope of Sgr B2 is obtained, which ranges from 6 to 46 K. The rotation
diagram of HCONH2 has also been derived toward Sgr B2(N) by Halfen et al.
(2011). They have detected a wide range of transitions with Eu ranging from 10
K to 200K. Their results show that both molecules have a cold extended
component and a hot component. In our observation, only transitions with low
Eu (<40 K) are used to draw the rotation diagram. Therefore, only one cold
component is obtained in each position.

Based on the results about the 12C and 13C in the section 4.1, the assumption
that all the transitions of HCONH2 are optically thin might not be correct in
all positions. If the emission is optically thick, the intensity of the
transition would be underestimated, which would lead to an underestimated
column density and an overestimated of $\rm T_{ex}$. For the positions near
Sgr B2(N) and Sgr B2(M), an absorption led by the strong continuum there could
also influence the results.

In addition, drawing rotation diagrams need the assumption that $T_{bg}$ could
be omitted comparing with $T_{ex}$ and the Rayleigh-Jeans law is valid (i.e.
$h\nu\ll kT$), so that equation 3 could be transferred to equation 2. However,
$T_{ex}$ in positions at the boundary of our observing area, such as position
(30″, 120″), the obtained excitation temperatures are lower than 10 K.
Combined with the high frequencies of transitions, the Rayleigh-Jeans law can
be hardly satisfied. In this case, the column densities obtained by the
rotation diagrams would be underestimated. The column densities were $\sim$
30%,$\sim$ 17% and $\sim$ 10% larger than the results obtained in section 3.1
when $T_{ex}$ is 7 K, 10 K, and 14 K, respectively.

Besides, the rotation diagrams are drawn only with a-type transitions. The
only detected b-type transition has a much stronger intensity than it should
be if both types can reach thermalization. Thus, the excitation temperature of
b-type transition can not be assumed to be same as that of a-type. Here we
only give the column densities based on the a-type transitions. To include
b-type transitions into the analysis, more observations are needed.

It is found that the excitation temperatures in the envelope are smaller than
the dust temperature, implying that these molecules are sub-thermalized. In
this instance, a non-LTE method would be a better way to calculate the
excitation temperatures and column densities. However, the energy population
can be well described with one single excitation temperature for the a-type
transitions of HCONH2. Therefore, the column densities are still reliable and
non-LTE effect will not affect our results too much.

###  4.3 Abundance ratio

To further study the relationship between CH3CONH2 and HCONH2, the abundance
ratio of them are calculated. HNCO would also be included in the discussion
according to our former research (Zheng et al., 2022). Assuming the same
excitation temperature as HCONH2, the column densities could be obtained by
the same way as CH3CONH2. In Sgr B2(M) and Sgr B2(N), there are many hot
cores, as well as strong continuum emissions, which make the spectra difficult
to be handled. Thus, the abundance ratio toward these two positions would not
be included in the discussion.

The distribution maps of the column density ratio are displayed in Figure 11.
From the figure, the abundance ratios between CH3CONH2 and HCONH2 are found to
range from 10 % to 20 %, except for one position with a smaller ratio, and two
positions with larger ratios. The two positions with the ratios larger than
20% are marked with yellow triangles in the left panel of Figure 11. The
spectra of those two molecules in these two positions are shown in Figure 8.
In those figures, the spectra of HCONH2 422-321 is chosen to compare with the
spectra of CH3CONH2, because they have a similar Eu. Thus, the comparsion
between those spectra can reflect the abundance ratio to some extent. The
ratio of CH3CONH2 to HCONH2 maximizes at position (-30″, 90″), with the values
of 25.7%. This constant ratio in most of the positions indicates that they
have the same response to the physical or chemical environment. Perhaps, there
is a chemical or physical link between CH3CONH2 and HCONH2. The ratio between
HCONH2 and HNCO range from 1.5% to 10.5%. The distribuion has a similar
feature with the distribuion of excitation temperature, imply a possible
relationship between the excitation temperature and the reactions that connect
these two molecules.

To compare the results with other sources, the abundance with respect to H2
are calculated. We use the Hi-GAL 350, 250, and 70 $\mu$m maps. the values are
the averaged values in a 30″beam to match the beam of IRAM 30m at 3 mm. Figure
12 shows the abundances with respect to H2. The blue lines are the power-law
fits of the observed positions, which are given by the equation $X(\rm
CH_{3}CONH_{2})$=0.55 $\times$ $X(\rm HCONH_{2})^{1.06}$ with a Pearson
coefficient of 0.79, and $X(\rm HCONH_{2})$=0.0017 $\times$ $X(\rm
HNCO)^{0.84}$ with a Pearson coefficient of 0.39. The dotted pink, dash-dotted
purple and dashed orange line correspond to the power-law fits given by López-
Sepulcre et al. (2015), $X(\rm HCONH_{2})$ = 0.04 $\times$ $X(\rm
HNCO)^{0.93}$, by Quénard et al. (2018), $X(\rm HCONH_{2})$ = 32.14 $\times$
$X(\rm HNCO)^{1.29}$, and by Colzi et al. (2021), $X(\rm HCONH_{2})$ = 0.006
$\times$ $X(\rm HNCO)^{0.73}$. The red points in the figure show the abundance
of HCONH2 and HNCO in Sgr B2 (N2) (Bonfand et al., 2019), G10.47+0.03 (Gorai
et al., 2020), G31.41+0.31 (Colzi et al., 2021). The data used to fit the pink
dotted lines in López-Sepulcre et al. (2015) include only the compact/inner
solution of rotation diagram analyses in shocks and star formation regions
with different masses. The sources used in Quénard et al. (2018) include
shocks and hot corinos. The line obtained in our work lies below the other
three lines, implying a relatively low abundance of HCONH2 comparing with HNCO
in the extended envelope. The low Pearson coefficient of 0.39 also indicates
the weak relationship between HNCO and HCONH2. It is likely that the formation
mechanism of these molecules are different in the envelope compared with the
mechanism in the compact sources. This conclusion has a good agreement with
the lower panel of Figure 2 of López-Sepulcre et al. (2015). For the line
between HCONH2 and CH3CONH2, a nearly linear relationship needs to be
explained with an updated chemical model.

Some uncertainties may affect the final results. First, the critical densities
vary with molecules, leading to the difference in excitation temperature. If
the excitation temperature of CH3CONH2 is lower than HCONH2, it would result
in a lower column density of CH3CONH2 and a smaller abundance ratio. Besides,
only the clean transitions of CH3CONH2-A are detected. The emission of
CH3CONH2-E, which may help to attain more accurate column density, is too weak
or blend with other molecules. What’s more, the low signal to noise ratio due
to the low abundance of CH3CONH2 may also affect the abundance ratio obtained
from the integrated intensity. Therefore, an observation with higher
resolution, higher sensitivity and wider bandwith are needed in the future.

###  4.4 Some special positions

Sgr B2(N): It is a massive star-formation region with many compact molecular
cores and strong cotinuum. Since there is strong continuum, the spectra in Sgr
B2(N) are not analyzed. The results in Sgr B2(N) drawn in the figures that
describe the spatial distribution of excitation temperature and abundance
ratio are the results of interpolation based the position besides, and thus
can not reflect the exact physical condition there. From the integrated
intensity maps of the transitions of both molecules, the peaks for transitions
with relatively higher upper state energies and the peak of the transition of
isotopic species are located in Sgr B2(N), which indicates the high column
density here. Halfen et al. (2011) found that the column densities of HCONH2
and CH3CONH2 towards Sgr B2(N) are 5.6 $\times$ 1014 cm-2 and 6.9 $\times$
1014 cm-2. Therefore, the column densities of HCONH2 and CH3CONH2 should peak
in Sgr B2(N). For the ratio of HCONH2/HNCO, the results attained by ALMA show
that the column density of HNCO, HCONH2, CH3CONH2 in Sgr B2(N2) is 2 $\times
10^{18}$ $cm^{-2}$, 2.6 $\times 10^{18}$ $cm^{-2}$, and 1.4 $\times 10^{17}$
$cm^{-2}$, respectively (Belloche et al., 2017). The ratio of HCONH2/HNCO is
130%. In Sgr B2(N3), Sgr B2(N4), Sgr B2(N5), the abundance ratio of HCONH2 to
HNCO is 25%, <56% and 44%, respectively(Bonfand et al., 2017). The abundance
ratio is higher than our results, implying a different mechanism there. The
trend that the ratio of HCONH2 to HNCO increases with the excitation
temperature (see Figure 7 and Figure11) is consistent with the larger ratio
found in Sgr B2(N). In terms of CH3CONH2/HCONH2, the abundance ratio in Sgr
B2(N1E) and Sgr B2(N1) is 9% and 15%(Li et al., 2021). In Sgr B2(N2), Belloche
et al. (2017) found the abundance ratio of CH3CONH2/HCONH2 to be 5.4%. In Sgr
B2(N1S), the abundance ratio of CH3CONH2/HCONH2 is 14% (Belloche et al.,
2019). The abundance ratio obtained from the hot core is consistent with that
in the cold envelope.

Sgr B2(M): It is a hot core at a later stage than Sgr B2(N). The continuum
there is stronger and consist of more dense cores than Sgr B2(N)(Schmiedeke et
al., 2016). The linewidths of the spectra there range from $\sim$ 6 to 15 km
s-1 and the LSR velocity is 60 to 66 km s-1 (Belloche et al., 2013). An
obvious absorption in the spectrum of HCONH2 404-303 and a slight absorption
in the spectrum of HCONH2 413-312 are detected there, while CH3CONH2 was not
detected. Perhaps the CH3CONH2 here has been destroyed or the spectrum have
strong absorption.

G+0.693: Among our observation positions, (30″, 60″) is the nearest from
G+0.693. In position (30″, 60″), the column density of CH3CONH2 is 2.6
$\times$ 1013 cm-2, while HCONH2 is 1.3 $\times$ 1014 cm-2. The abundance
ratio of HCONH2/HNCO and CH3CONH2/HCONH2 is 3.9% and 19.2%, respectively. In
the observation of Zeng et al. (2018), the ratio of HCONH2/HNCO is 20%. If
only a-HCONH2 is considered, the ratio is 1.6%. In the work of Zeng et al.
(2023), the column density of HCONH2 is calculated from the isotope species
H13CONH2, which is 2.5 $\times$ 1014 cm-2. The 12C/13C ratio they used is 40,
which is larger than our result of 28.7. The column density of HCONH2 is
consequently larger than the column density we obtain. Because multiple
transitions of CH3CONH2, they obtain the excitation temperature of 7.4 K and
7.8 K for CH3CONH2-A and CH3CONH2-E, lower than the temperature we used. If
the same excitation temperature is used, a similar column density of
CH3CONH2-A can be obtained. The abundance ratio in their work is 46%,
considering both CH3CONH2-A and CH3CONH2-E.

###  4.5 Chemical model

To investigate the synthesis mechanism of peptide-like molecules HCONH2 and
CH3CONH2 in the region extending among $100\arcsec$ from Sgr B2, we study the
evolution of HCONH2 and CH3CONH2 in chemical models. The simulations provided
by Wang et al. (2021) are adopted for comparing with observations, since most
observed positions still locate in the low-density envelope around Sgr B2
(Hüttemeister et al., 1993, 1995; Schmiedeke et al., 2016), for which the
chemical evolution had been calculated via Monte Carlo method and explained
different distributions of seven complex organic molecules (COMs). Besides
CH2OHCHO, CH3OCHO, t-HCOOH, C2H5OH, CH3NH2, CH3OCH3, and C2H5CN analyzed by
Wang et al. (2021), HCONH2 and CH3CONH2 are already included in the chemical
reaction network. Figure 13 presents the relationship between the abundance
$X$(CH3CONH2) (with respect to H2) and $X$(HCONH2), and the relationship
between $X$(HCONH2) and $X$(HNCO) in the best-fit model (the same one as
proposed by Wang et al. (2021)) comparing with observations, while the other
models cannot fit observations. The corresponding physical evolution is that
the low density extended region around Sgr B2 ($n_{\mathrm{H}}=2\times
10^{3}\,\mathrm{cm^{-3}}$) underwent a cold phase with gas and dust
temperature $T_{\mathrm{gas}}=T_{\mathrm{dust}}=10\,\mathrm{K}$, then a warm-
up phase of increasing both temperatures simultaneously to reach the maximum
200 K, including an X-ray flare from Sgr A* with a short duration of no more
than 100 yr when $T_{\mathrm{gas}}=T_{\mathrm{dust}}=20\,\mathrm{K}$ (for
details see Table 1 and Section 3.2.2 in Wang et al. (2021)). Under such
circumstance, simulated $X$(CH3CONH2), $X$(HCONH2), and $X$(HNCO) can match
observed abundances at $T_{\mathrm{dust}}\sim 53-56\,\mathrm{K}$, $105-115$ K,
and $170-190$ K, respectively. However, considering the relatively low dust
temperature $T_{\mathrm{dust}}\sim 20-30\,\mathrm{K}$ in the extended envelope
according to the dust continuum, our chemical models still need to be further
modified.

We leave rectification of the chemical reaction network for a future detailed
study. Here we only discuss those reactions that are key for the species
concern us here and need to be further assessed. According to current
simulations, the most important reactions for producing HCONH2, CH3CONH2, and
HNCO at $T_{\mathrm{dust}}\sim 53-56\,\mathrm{K}$ are JNH2 \+ JHCO
$\rightarrow$ HCONH2, JNH2 \+ JCH3CO $\rightarrow$ CH3CONH2, and JHNCO
$\rightarrow$ HNCO, respectively, and the letter J represents species on the
grain. Therefore, the reactive desorption driven by exothermic reactions
(Garrod et al., 2007; Vasyunin & Herbst, 2013) is the most significant
mechanism for producing HCONH2 and CH3CONH2 in relatively cold environment,
which is also concluded for the other seven COMs (Wang et al., 2021). For HNCO
which has already been synthesized abundantly on the grain surface, the
thermal desorption is the main mechanism for increasing its gaseous abundance
since its evaporation temperature is about 50 K.

Similarly, the thermal desorption induces rapidly increasing abundances of
HCONH2 and CH3CONH2 at $T_{\mathrm{dust}}\sim 105-115\,\mathrm{K}$, which
exceeds their evaporation temperatures (about 93 K and 105 K, respectively,
calculated with the binding energies of 5556 K and 6281 K presented by Garrod
(2013) and via equation (6) presented by Du et al. (2012)). In addition, the
gaseous ion-molecule reactions involving C+ are the main approach for
depleting HCONH2 and CH3CONH2 molecules in the warm-up phase, which is similar
to seven COMs (Wang et al., 2021). These reactions may explain the evolution
of HCONH2 and CH3CONH2 in the region close to Sgr B2(N) and Sgr B2(M) with
higher density and temperature. Nevertheless, for producing enough HCONH2 and
CH3CONH2 molecules at $T_{\mathrm{dust}}\sim 20-30\,\mathrm{K}$ in the
extended envelope, more efficient non-thermal desorption mechanisms need to be
investigated in the future analysis, not only reactive desorption but also
photodesorption and Eley-Rideal mechanism (Garrod et al., 2007; Öberg et al.,
2010; Cernicharo et al., 2012; Vasyunin & Herbst, 2013; Vastel et al., 2014;
Ruaud et al., 2015).

Besides non-thermal desorption processes, other reasons can cause the
discrepancy between best-fit dust temperatures derived from simulations and
observations. 1) The uncertainties of many parameters for calculating reaction
rates in chemical models are large, especially the binding energy (or
desorption energy) of each species (Penteado et al., 2017). For example, in
this chemical reaction network, the adopted binding energies of HCONH2 and
HNCO are 5556 K and 2850 K originating from OSU network database and Garrod
(2013), while new calculated values 5468 K and 4684 K using the Gaussian 09
suite of programs show a smaller difference (Gorai et al., 2020), which may
induce their evolution to become similar. Additionly, contrast to the adopted
fix values in most chemical models for simplicity, the binding energies
measured by laboratory experiments vary with the coverage of grain surface (He
et al., 2016; Behmard et al., 2019). The binding energy distributions are also
inferred by theoretical computations (Ferrero et al., 2020; Perrero et al.,
2022) and significantly influence the efficiencies of thermal desorption and
grain surface two-body reactions (Penteado et al., 2017; Grassi et al., 2020),
which may increase the abundances of HCONH2 and CH3CONH2 at
$T_{\mathrm{dust}}\sim 20-30\,\mathrm{K}$. 2) Some new reactions for
synthesizing HCONH2 and CH3CONH2 may have not been considered in
aforementioned models. One reaction is the gas-phase reaction NH2 \+ H2CO
$\rightarrow$ HCONH2 \+ H, which has been used to explain the observation
toward the shock region L1157-B1(Codella et al., 2017). The dual-cyclic
hydrogen addition and abstraction reactions between HNCO and HCONH2 in ice
grains derived from experiments (Haupa et al., 2019) are not included,
neither. Thus, more accurate chemical simulations adopting binding energy
distributions and new reactions are necessary to fit observed abundances in
the envelope around Sgr B2 with low dust temperature in the future study. 3)
The aforementioned models have not adopted multiple physical mechanisms
simultaneously to investigate whether an individual mechanism can induce a
good fit comparing with observations. However, the environment of Sgr B2 is
complex, more sophisticated physical model including not only X-ray flare from
Sgr A* (Marin et al., 2023) but also shocks should be considered in
simulations. Such accurate physical model demands more observations to limit
it.

##  5 Summary

We have performed mapping observation toward Sgr B2 to further study the
spatial distributions of the peptide-like molecules and the relationship
between them. The obtained results are listed there:

1\. HCONH2 and CH3CONH2 are detected to have an extended distribution toward
Sgr B2, with the abundance ratio range from 10% to 20%. The abundance of
CH3CONH2 was enhanced toward to north-west of Sgr B2. The excitation
temperature in the envelop of Sgr B2 ranges from 6K to 46 K, based on the
rotation diagram of HCONH2.

2\. The isotopic molecule H13CONH2 is also detected toward 12 positions of Sgr
B2. The emission of H13CONH2 404-303 indicated that HCONH2 404-303 has
absorption toward Sgr B2(N). The ratio of 12C/13C is 28.7 toward Sgr B2
envelope.

3\. A chemical model including a cold phase and a warm-up phase with a short
duration X-ray burst of no more than 100 yr at
$T_{\mathrm{gas}}=T_{\mathrm{dust}}=20\,\mathrm{K}$ is used to explain the
observed abundances of HCONH2 and CH3CONH2. The simulations can fit observed
abundances at $T_{\mathrm{dust}}\sim 53-56\,\mathrm{K}$, $105-115$ K, and
$170-190$ K, respectively. The reactive desorption driven by exothermic
reactions dominate the synthesis of these two peptide-like molecules in
relatively cold environment. Such dust temperatures are still higher than
observations, which requires more accurate chemical models for explaining it.

This work is based on observations carried out under project number 170-18
with the IRAM 30m telescope. IRAM is supported by INSU/CNRS (France), MPG
(Germany) and IGN (Spain). This work has been supported by the National Key
R&D Program of China (No. 2022YFA1603101). This work is also supported by CDMS
database. We thank JinJin Xie for the suggestions for the draft. YW
acknowledges the support by the Natural Science Foundation of Jiangsu Province
(Grant Number BK20221163).

Figure 1: The gray-scale and contours show the spatial distribution of
different transitions of HCONH2. The figures are listed in order of increasing
upper state energy. The first figure is the map of HCONH2 11,1-00,0 at
82549.562 MHz. The contour levels start at 2 K km s-1 with a step of 0.4 K km
s-1. The second figure is the map of HCONH2 40,4-30,3 at 84542.330 MHz. The
contour levels start at 7 K km s-1 with a step of 2.5 K km s-1. The third
figure is the map of HCONH2 41,3-31,2 at 87848.874 MHz. The contour levels
start at 8.4 K km s-1 with a step of 3 K km s-1. The fourth figure is the map
of HCONH2 42,2-32,1 at 85093.272 MHz. The contour levels start at 3.3 K km s-1
with a step of 3 K km s-1. The fiveth figure is the map of HCONH2 42,3-32,2 at
84807.795 MHz. The contour levels start at 3 K km s-1 with a step of 2 K km
s-1. The sixth figure is the map of HCONH2 43,2-33,1 and 43,1-33,0 at
84888.994 MHz and 84890.987, respectively. The contour levels start at 2.5 K
km s-1 with a step of 2.5 K km s-1. Sgr B2(N), Sgr B2(M), and G+0.693 are
labeled with ${}^{\prime\prime}\times"$. The beam size are shown in the left
corner of each panel.

Figure 2: The spectra of HCONH2 in position (30, 60) and Sgr B2(N).
Frequencies are indicated with the red lines above the spectra. The $v_{\rm
sys}$, determined by H13CCCN 10-9, are labeled with blue dashed lines. The
value of $v_{\rm sys}$ is labeled in the top left corner of each panel.

Figure 3: The spectra of HCONH2 404-303 and H13CONH2 404-303. The $v_{\rm
sys}$ are labeled with blue dashed lines. The spectra of HCONH2 404-303 are
divided by 25, 20, 15 and 3 to compare with the spectra of H13CONH2 in
different positions.The value of $v_{\rm sys}$ is labeled in the top left
corner of each panel.

Figure 4: The distribution of H13CONH2 404-303 at 84390.679 MHz. The contour
map starts from 5 $\sigma$ with the step of 5 $\sigma$. 1 $\sigma$ is about
0.43 K km s-1. Sgr B2(N) and Sgr B2(M) are labeled with
${}^{\prime\prime}\times"$. Beam size is shown in the bottom left corner. The
area in the blue square shows the region used to average the spectra of the
H13CONH2.

Figure 5: The averaged spectra of the H13CONH2 in the right region of Sgr B2.
The red window represents the integrated velocity range, which is 60 km s-1 to
75 km s-1.

Figure 6: The positions selected to draw rotation diagrams. The selected
position are labeled with green ${}^{\prime\prime}\times"$. Sgr B2(N), Sgr
B2(M), and G+0.693 are labeled as blue ${}^{\prime\prime}\times"$.

Figure 7: The distribution of excitation temperature and column density of
HCONH2. The contour levels of the left panel start at 12 K with a step of 4 K.
The contour levels of the right panel start at 1.3 $\times 10^{14}$ cm-2 with
a step of 0.4 $\times 10^{13}$ cm-2. Figure 8: The spectra of CH3CONH2 and
HCONH2 422-321 in Sgr B2. The red profiles correspond to the spectra of HCONH2
422-321, while the black profiles are the spectra of CH3CONH2. The positions
are labeled in the top left corner. The $v_{\rm sys}$ in difference positions
are labeled with blue dashed lines. The value of $v_{\rm sys}$ is labeled in
the top left corner of each panel.

Figure 9: The integrated intensity map of CH3CONH2 emission. The integrated
intensities of five transitions listed in Table 1 were used together to plot
the map. The contour levels of CH3CONH2 emission start at 5 $\sigma$ with a
step of 5 $\sigma$. $\sigma\approx$ 0.07 km s-1 K for this map. Sgr B2(N), Sgr
B2(M), and G+0.693 are labeled with ${}^{\prime\prime}\times"$. Beam size is
shown in the bottom left corner.

Figure 10: The distribution of column densities in Sgr B2. The gray-scale and
the contour level represent the column density of HCONH2 and CH3CONH2
respectively. The contour levels start at 0.7 $\times 10^{13}$ cm-2 with the
step of 1 $\times 10^{14}$ cm-2.

Figure 11: The distribution of the ratio between CH3CONH2, HCONH2 and HNCO.
The left figure corresponds to the ratio of CH3CONH2 to HCONH2, of which the
contour levels start at 12.5% and increase in steps of 2.5%. The positions
with the ratios larger than 20% were pointed out with the yellow triangles.
The figure in the right is ratio of HCONH2 to HNCO, of which the contour
levels start at 4% and increase in steps of 1.5%.

Figure 12: The abundance of HCONH2, CH3CONH2, and HNCO, with respect to H2.
The blue lines are the power-law fitted results in our work. The dotted pink,
dash-dotted purple and dashed orange line in the right panel are the results
of López-Sepulcre et al. (2015), Quénard et al. (2018), and Colzi et al.
(2021). The red points in the figure show the abundance of HCONH2 and HNCO in
Sgr B2 (N2) (Bonfand et al., 2019), G10.47+0.03 (Gorai et al., 2020),
G31.41+0.31 (Colzi et al., 2021). The black points are the observed abundances
measured in the different positions of Sgr B2 complex.

Figure 13: Comparison of observed abundances of CH3CONH2, HCONH2, and HNCO
(with respect to H2) with simulated abundances using the best-fit chemical
model in Wang et al. (2021). The red solid lines represent the evolution of
$X$(CH3CONH2) versus $X$(HCONH2) and $X$(HCONH2) versus $X$(HNCO) at different
time in the warm-up phase; the dust temperature at a few selected points are
labelled. The results for $T_{\mathrm{dust}}\sim 10-60\,\mathrm{K}$,
$60-100\,\mathrm{K}$, $100-130\,\mathrm{K}$, and $130-200\,\mathrm{K}$ are
plotted as squares, circles, diamonds, and triangles, respectively. The best-
fit model is an evolving model with the following parameters:
$n_{\mathrm{H}}=2\times 10^{3}\,\mathrm{cm^{-3}}$, $A_{\mathrm{V}}=10$, the
duration of the cold phase $t_{\mathrm{cold}}=3\times 10^{5}\,\mathrm{yr}$,
the duration of the warm-up phase $t_{\mathrm{warmup}}=2\times
10^{5}\,\mathrm{yr}$, the maximum temperature after the warm-up
$T_{\mathrm{max}}=200\,\mathrm{K}$, the external UV radiation scaling factor
$G_{0}=10^{4}$ with an X-ray burst at
$T_{\mathrm{gas}}=T_{\mathrm{dust}}=20\,\mathrm{K}$ (the total timescale
$t_{\mathrm{total}}=3.459\times 10^{5}\,\mathrm{yr}$), the effective
ionization rate $\zeta_{\mathrm{CR}}=1.3\times 10^{-13}\,\mathrm{s^{-1}}$ and
the duration $t=10^{2}\,\mathrm{yr}$ (for details see Table 1 and Section
3.2.2 in Wang et al. (2021)).

Table 1: The transitions of HCONH2 and CH3CONH2

Molecule | Transition | Rest Freq. | $E_{u}$ | log10(A) | $\mu^{2}S$ | Comments | Reference
---|---|---|---|---|---|---|---
|  | MHz | K | s-1 | $D^{2}$ |  |
HCONH2 | 11,1-00,0 | 82549.562 | 3.962 | -5.8001 | 0.726 | Partially blend with C2H5CN,v=1. |
| 40,4-30,3 | 84542.330 | 10.16 | -4.3888 | 52.279 | No blend. |
| 42,3-32,2 | 84807.795 | 22.10 | -4.5094 | 39.227 | No blend. |
| 43,2-33,1 | 84888.994 | 37.00 | -4.7422 | 22.884 | No blend. | (1)
| 43,1-33,0 | 84890.987 | 37.01 | -4.7422 | 22.883 | No blend. |
| 42,2-32,1 | 85093.272 | 22.12 | -4.5051 | 39.227 | No blend. |
| 41,3-31,2 | 87848.874 | 13.52 | -4.3666 | 49.030 | No blend. |
H13CONH2 | 40,4-30,3 | 84390.679 | 10.14 | -4.3912 | 52.259 | No blend. | (1)
CH3CONH2-A | 72,6,0-61,5,0 | 87629.757 | 18.77 | - | 65.860 | No blend. |
| 80,8,0-71,7,0 | 87632.434 | 19.82 | - | 94.010 | No blend. |
| 81,8,0-71,7,0 | 87632.443 | 19.82 | - | 5.868 | No blend. | (2)
| 80,8,0-70,7,0 | 87632.501 | 19.82 | - | 5.868 | No blend. |
| 81,8,0-70,7,0 | 87632.510 | 19.82 | - | 94.010 | No blend. |

Note: The transitions of HCONH2 and CH3CONH2 used for mapping. For CH3CONH2,
only A-spieces were detected. Col. (1) chemical formula; Col. (2) transition
quantum number (Belloche et al., 2013); Col. (3) rest frequency; Col. (4):
upper state energy level (K); Col. (5): emission coefficient; Col. (6):
$\mu^{2}$ is the dipole moment, and S is the line strength; Col. (7) comments.

Reference: (1)Kryvda et al. (2009), (2) Ilyushin et al. (2004)

Table 2: The emission size and peak position of HCONH2 and CH$3$CONH2

molecule | transition | peak position | emission size
---|---|---|---
|  |  | ″
HCONH2 | 11,1-00,0 | (19, 47) | 81
| 40,4-30,3 | (-29, -55) | 53
| 41,3-31,2 | (-29, -52) | 57
| 42,2-32,1 | (-4, -4) | 37
| 42,3-32,2 | (-5, -5) | 38
| 43,2-33,1 | (0, 0) | 20
| 43,1-33,0 |  |
CH3CONH2-A | 72,6,0-61,5,0 | (-4, -3) | 47
| 80,8,0-71,7,0 |  |
| 81,8,0-71,7,0 |  |
| 80,8,0-70,7,0 |  |
| 81,8,0-70,7,0 |  |

Note: the emission size listed in Col(3) is defined by the equivalent radius
of the area where the emission is stronger than half of the emission at the
peak position.

Table 3: The intensity ratio between H13CONH2 and HCONH2 position | Velocity range | I${}_{H^{13}CONH_{2}}$ | I${}_{HCONH_{2}}$ | ratio | $\tau$
---|---|---|---|---|---
| km s-1 | K km s-1 | K km s-1 | % |
(0, -60) | 48 75 | 0.44(0.08) | 9.93(0.11) | 22.7(4.0) | 0.51
(-30, 0) | 55 85 | 0.54(0.05) | 14.28(0.10) | 26.4(2.5) | 0.18
(-30, -30) | 50 80 | 0.52(0.05) | 15.81(0.10) | 30.7(2.7) | 0.04
(0, 60) | 50 86 | 0.34(0.05) | 12.73(0.07) | 37.9(6.0) | 0
(30, 60) | 50 85 | 0.53(0.08) | 14.29(0.09) | 27.2(3.9) | 0.11
(-60, 30) | 58 80 | 0.26(0.05) | 8.15(0.08) | 31.3(5.9) | 0
(-30, -60) | 48 78 | 0.67(0.07) | 18.64(0.10) | 27.9(3.1) | 0.06
(0, 90) | 45 85 | 0.21(0.06) | 11.02(0.14) | 51.8(15.6) | 0
(0, -90) | 45 70 | 0.46(0.05) | 14.66(0.07) | 31.9(3.1) | 0
(0, -120) | 48 78 | 0.31(0.6) | 11.11(0.07) | 35.3(7.2) | 0
(60, 60) | 48 78 | 0.36(0.07) | 11.98(0.08) | 33.3(6.2) | 0
(0, 0) | 55 78 | 1.53(0.17) | 8.96(0.09) | 5.9(0.7) | 5.30
west Sgr B2 | 60 75 | 0.09(0.01) | 2.7(0.02) | 28.7(1.7) |

Table 4: Column density of HCONH2 and CH3CONH2 rac | decl | Tex | N${}_{HCONH_{2}}$ | N${}_{CH_{3}CONH_{2}}$ | NHNCO | r(CH3CONH2/HCONH2) | r(HCONH2/HNCO)
---|---|---|---|---|---|---|---
$\arcsec$ | $\arcsec$ | K | $\times 10^{14}cm^{-2}$ | $\times 10^{13}cm^{-2}$ | $\times 10^{15}cm^{-2}$ | % | %
-60 | -60 | 14.2$\pm$4.0 | 0.8$\pm$0.2 | 1.0$\pm$0.4 | 1.8$\pm$0.4 | 12.9 | 4.1
30 | 0 | 27.8$\pm$11.9 | 0.9$\pm$0.3 |  $\leq$ 0.6 | 2.0$\pm$0.3 |  $\leq$ 7.0 | 4.4
-30 | 0 | 26.3$\pm$5.0 | 2.5$\pm$0.4 | 2.3$\pm$0/4 | 4.1$\pm$0.3 | 9.1 | 6.3
0 | 30 | 19.4$\pm$4.5 | 1.4$\pm$0.3 | 1.9$\pm$0.5 | 3.4$\pm$0.4 | 14.3 | 4.0
-30 | 30 | 15.9$\pm$4.9 | 1.2$\pm$0.3 | 2.3$\pm$0.9 | 3.0$\pm$0.6 | 19.4 | 4.0
-30 | -30 | 27.2$\pm$8.8 | 3.1$\pm$0.7 | 4.6$\pm$1.1 | 4.8$\pm$0.6 | 14.8 | 6.5
30 | 30 | 19.7$\pm$11.6 | 1.3$\pm$0.6 | 2.6$\pm$1.5 | 3.5$\pm$1.1 | 19.9 | 3.8
30 | -30 | 33.4$\pm$14.0 | 1.1$\pm$0.3 |  $\leq$ 0.6 | 1.9$\pm$0.3 |  $\leq$ 5.7 | 5.4
0 | 60 | 13.4$\pm$4.0 | 1.1$\pm$0.4 | 2.2$\pm$1.0 | 3.3$\pm$0.8 | 19.6 | 3.5
60 | 0 | 18.9$\pm$13.1 | 0.3$\pm$0.2 |  $\leq$ 0.5 | 1.0$\pm$0.4 |  $\leq$ 16.6 | 2.8
-60 | 0 | 16.3$\pm$7.9 | 0.9$\pm$0.4 | 1.5$\pm$0.9 | 2.5$\pm$0.8 | 15.7 | 3.8
0 | -60 | 46.1$\pm$15.8 | 4.6$\pm$0.7 | 7.6$\pm$1.2 | 4.5$\pm$0.4 | 16.7 | 10.2
30 | 60 | 13.1$\pm$3.0 | 1.3$\pm$0.3 | 2.6$\pm$0.9 | 3.4$\pm$0.6 | 19.6 | 3.9
-30 | 60 | 15.5$\pm$6.9 | 0.7$\pm$0.2 | 1.3$\pm$0.8 | 3.1$\pm$0.9 | 19.6 | 2.2
60 | 30 | 12.3$\pm$3.7 | 0.5$\pm$0.2 | 0.8$\pm$0.4 | 1.7$\pm$0.4 | 16.5 | 3.0
-60 | 30 | 12.9$\pm$3.6 | 0.8$\pm$0.3 | 1.8$\pm$0.8 | 2.9$\pm$0.7 | 22.7 | 2.8
60 | -30 | 23.1$\pm$15.1 | 0.4$\pm$0.2 |  $\leq$ 0.6 | 1.0$\pm$0.3 |  $\leq$ 15.6 | 4.2
-60 | -30 | 15.5$\pm$5.5 | 1.1$\pm$0.3 | 1.4$\pm$0.7 | 2.6$\pm$0.6 | 13.3 | 4.2
30 | -60 | 23.2$\pm$8.6 | 0.8$\pm$0.2 |  $\leq$ 0.6 | 1.2$\pm$0.2 |  $\leq$ 7.2 | 6.2
-30 | -60 | 24.0$\pm$7.4 | 3.2$\pm$0.7 | 4.8$\pm$1.3 | 3.6$\pm$0.5 | 15.2 | 8.9
-90 | 0 | 14.8$\pm$9.8 | 0.3$\pm$0.2 |  $\leq$ 0.4 | 1.7$\pm$0.8 |  $\leq$ 11.7 | 2.1
0 | 90 | 9.9$\pm$1.5 | 0.7$\pm$0.1 | 1.2$\pm$0.4 | 2.9$\pm$0.5 | 16.9 | 2.4
0 | -90 | 17.3$\pm$5.3 | 1.8$\pm$0.5 | 2.1$\pm$0.8 | 1.7$\pm$0.3 | 12.1 | 10.1
60 | 90 | 9.5$\pm$1.0 | 0.6$\pm$0.1 |  $\leq$ 0.4 | 2.3$\pm$0.3 |  $\leq$ 6.7 | 2.6
30 | 90 | 10.8$\pm$3.5 | 0.7$\pm$0.3 | 1.4$\pm$0.8 | 3.0$\pm$0.9 | 19.6 | 2.4
-30 | 90 | 10.0$\pm$2.3 | 0.6$\pm$0.2 | 1.5$\pm$0.7 | 2.4$\pm$0.6 | 25.7 | 2.5
-60 | 90 | 16.7$\pm$18.7 | 0.4$\pm$0.3 |  $\leq$ 0.5 | 1.8$\pm$1.3 |  $\leq$ 14.2 | 2.0
-90 | 90 | 9.7$\pm$3.5 | 0.3$\pm$0.1 |  $\leq$ 0.4 | 1.3$\pm$0.5 |  $\leq$ 16.5 | 2.0
60 | -90 | 19.4$\pm$15.6 | 0.6$\pm$0.3 |  $\leq$ 0.5 | 1.3$\pm$0.6 |  $\leq$ 9.8 | 4.3
30 | -90 | 16.9$\pm$7.6 | 0.7$\pm$0.3 |  $\leq$ 0.5 | 1.0$\pm$0.3 |  $\leq$ 6.5 | 7.0
-30 | -90 | 15.3$\pm$4.3 | 1.4$\pm$0.4 | 1.9$\pm$0.7 | 2.0$\pm$0.4 | 13.6 | 6.9
-60 | -90 | 14.8$\pm$10.8 | 0.4$\pm$0.3 |  $\leq$ 0.5 | 1.3$\pm$0.7 |  $\leq$ 12.0 | 3.2
-90 | -90 | 10.2$\pm$3.3 | 0.2$\pm$0.1 |  $\leq$ 0.4 | 1.0$\pm$0.3 |  $\leq$ 21.5 | 2.1
-90 | 30 | 13.0$\pm$7.5 | 0.5$\pm$0.3 | 0.6$\pm$0.6 | 2.0$\pm$0.9 | 12.6 | 2.5
-90 | 60 | 11.9$\pm$6.2 | 0.4$\pm$0.2 |  $\leq$ 0.4 | 1.7$\pm$0.8 |  $\leq$ 9.5 | 2.4
-120 | 0 | 15.7$\pm$14.6 | 0.4$\pm$0.3 |  $\leq$ 0.5 | 1.8$\pm$1.1 |  $\leq$ 14.4 | 2.0
-120 | 30 | 12.3$\pm$7.1 | 0.4$\pm$0.2 |  $\leq$ 0.4 | 1.9$\pm$0.9 |  $\leq$ 10.8 | 2.2
-120 | 60 | 12.5$\pm$5.9 | 0.3$\pm$0.1 |  $\leq$ 0.3 | 1.5$\pm$0.6 |  $\leq$ 11.7 | 2.0
Table 4: Continued. rac | decl | Tex | N${}_{HCONH_{2}}$ | N${}_{CH_{3}CONH_{2}}$ | NHNCO | r(CH3CONH2/HCONH2) | r(HCONH2/HNCO)
---|---|---|---|---|---|---|---
$\arcsec$ | $\arcsec$ | K | $\times 10^{14}cm^{-2}$ | $\times 10^{13}cm^{-2}$ | $\times 10^{15}cm^{-2}$ | % | %
-90 | -30 | 16.6$\pm$12.8 | 0.4$\pm$0.2 |  $\leq$ 0.4 | 1.9$\pm$0.9 |  $\leq$ 10.8 | 2.0
-90 | -60 | 19.4$\pm$26.0 | 0.4$\pm$0.3 |  $\leq$ 0.5 | 1.5$\pm$1.1 |  $\leq$ 14.4 | 2.4
0 | 120 | 7.1$\pm$1.4 | 0.3$\pm$0.1 |  $\leq$ 0.6 | 1.9$\pm$0.5 |  $\leq$ 16.8 | 1.8
30 | 120 | 6.2$\pm$0.2 | 0.3$\pm$0.0 |  $\leq$ 1.0 | 2.2$\pm$0.1 |  $\leq$ 28.5 | 1.6
60 | 120 | 7.6$\pm$1.1 | 0.2$\pm$0.1 |  $\leq$ 0.7 | 1.6$\pm$0.3 |  $\leq$ 32.2 | 1.5
-30 | -120 | 14.7$\pm$4.4 | 0.5$\pm$0.1 |  $\leq$ 0.4 | 1.2$\pm$0.2 |  $\leq$ 8.0 | 4.4
0 | -120 | 13.2$\pm$3.9 | 1.0$\pm$0.3 | 1.4$\pm$0.6 | 1.6$\pm$0.4 | 14.4 | 6.2
30 | -120 | 12.4$\pm$3.5 | 0.7$\pm$0.2 | 0.9$\pm$0.4 | 1.1$\pm$0.3 | 12.4 | 6.5
60 | 60 | 11.4$\pm$2.1 | 1.0$\pm$0.2 | 1.9$\pm$0.6 | 3.0$\pm$0.5 | 19.2 | 3.3
-60 | 60 | 14.5$\pm$6.3 | 0.6$\pm$0.2 | 1.1$\pm$0.7 | 2.3$\pm$0.7 | 19.6 | 2.4
60 | -60 | 15.8$\pm$5.7 | 0.6$\pm$0.2 | 0.6$\pm$0.3 | 1.0$\pm$0.2 | 10.7 | 5.5
60 | -120 | 21.6$\pm$30.1 | 0.5$\pm$0.5 |  $\leq$ 0.7 | 1.3$\pm$0.9 |  $\leq$ 12.5 | 4.0
0 | -150 | 18.1$\pm$18.3 | 0.8$\pm$0.6 | 1.1$\pm$1.2 | 1.5$\pm$0.9 | 12.9 | 5.4
30 | -150 | 12.1$\pm$6.6 | 0.6$\pm$0.3 | 0.8$\pm$0.7 | 1.1$\pm$0.5 | 13.8 | 5.0
0 | -180 | 14.1$\pm$8.8 | 0.5$\pm$0.3 |  $\leq$ 0.6 | 1.7$\pm$0.8 |  $\leq$ 11.5 | 3.0
30 | -180 | 12.2$\pm$7.7 | 0.4$\pm$0.2 |  $\leq$ 0.4 | 1.0$\pm$0.5 |  $\leq$ 11.9 | 3.7

Note. Col(1) and Col(2): the equatorial offsets of emission with respect to
Sgr B2(N); Col(3): the excitation temperature; Col(4): the column densities of
HCONH2; Col(5): the column densities of CH3CONH2; Col(6): the column densities
of HNCO; Col(7): the column density ratio of CH3CONH2 to HCONH2. Col(8): the
column density ratio of HCONH2 to HNCO.

Table A1: The integrated intensities, the first moment (vm1, the intensity-weighted velocity) and second moment ($\sigma_{m2},$the intensity-weighted velocity dispersion) of the transitions of HCONH2.  rac | dec | 43,2-33,1 and 43,1-33,0 | 11,1-00,0 | 40,4-30,3
---|---|---|---|---
|  | intensity | vm1 | $\sigma_{m2}$ | intensity | vm1 | $\sigma_{m2}$ | intensity | vm1 | $\sigma_{m2}$
″ | ″ | K km s-1 | km s-1 | km s-1 | K km s-1 | km s-1 | km s-1 | K km s-1 | km s-1 | km s-1
-60.0 | -60.0 | 0.9$\pm$0.1 | 57.4 | 18.4 | 2.2$\pm$0.1 | 62.3 | 17.1 | 7.7$\pm$0.1 | 63.6 | 21.1
30.0 | 0.0 | 1.7$\pm$0.1 | 67.2 | 24.3 | 0.8$\pm$0.0 | 65.3 | 14.8 | 4.2$\pm$0.1 | 69.6 | 21.1
-30.0 | 0.0 | 5.2$\pm$0.1 | 63.8 | 15.9 | 3.0$\pm$0.1 | 69.2 | 16.8 | 14.9$\pm$0.1 | 69.9 | 16.0
0.0 | 30.0 | 2.7$\pm$0.1 | 64.7 | 18.4 | 3.7$\pm$0.1 | 70.4 | 20.6 | 10.8$\pm$0.1 | 69.5 | 17.9
0.0 | -30.0 | 6.7$\pm$0.1 | 59.3 | 14.5 | 1.3$\pm$0.1 | 64.6 | 15.8 | 0.0$\pm$0.0 | 61.6 | 29.2
-30.0 | 30.0 | 1.3$\pm$0.1 | 63.0 | 14.5 | 3.7$\pm$0.1 | 68.0 | 17.9 | 11.5$\pm$0.1 | 69.2 | 14.6
-30.0 | -30.0 | 5.5$\pm$0.1 | 58.8 | 23.4 | 3.7$\pm$0.1 | 65.4 | 19.9 | 18.2$\pm$0.1 | 64.5 | 21.6
30.0 | 30.0 | 1.2$\pm$0.1 | 64.8 | 18.4 | 3.9$\pm$0.0 | 68.6 | 22.2 | 9.6$\pm$0.1 | 69.6 | 23.1
30.0 | -30.0 | 1.9$\pm$0.0 | 61.7 | 19.5 | 0.7$\pm$0.1 | 62.1 | 16.4 | 4.0$\pm$0.1 | 65.2 | 19.0
0.0 | 60.0 | 1.0$\pm$0.1 | 64.1 | 17.2 | 4.1$\pm$0.1 | 67.8 | 21.4 | 13.1$\pm$0.1 | 68.6 | 20.6
60.0 | 0.0 | 0.4$\pm$0.1 | 56.0 | 13.0 | 1.0$\pm$0.1 | 62.3 | 18.1 | 1.6$\pm$0.1 | 60.5 | 13.8
-60.0 | 0.0 | 0.8$\pm$0.1 | 61.3 | 15.9 | 2.7$\pm$0.1 | 66.2 | 20.7 | 8.9$\pm$0.1 | 67.8 | 20.6
0.0 | -60.0 | 7.1$\pm$0.1 | 58.9 | 15.9 | 2.1$\pm$0.1 | 62.4 | 18.0 | 10.7$\pm$0.1 | 59.5 | 15.3
30.0 | 60.0 | 1.2$\pm$0.1 | 65.2 | 22.5 | 4.3$\pm$0.1 | 66.7 | 19.7 | 15.0$\pm$0.1 | 68.2 | 24.4
-30.0 | 60.0 | 0.3$\pm$0.1 | 64.7 | 13.0 | 2.5$\pm$0.1 | 67.2 | 18.0 | 7.1$\pm$0.1 | 66.6 | 16.6
60.0 | 30.0 | 0.6$\pm$0.1 | 60.0 | 17.2 | 2.5$\pm$0.1 | 62.7 | 19.1 | 5.0$\pm$0.1 | 63.7 | 16.6
-60.0 | 30.0 | 0.7$\pm$0.1 | 60.8 | 20.5 | 3.2$\pm$0.1 | 68.1 | 17.6 | 9.4$\pm$0.1 | 69.4 | 20.1
60.0 | -30.0 |  $\leq$ 0.2 | 57.3 | 22.5 | 0.7$\pm$0.1 | 57.2 | 17.7 | 3.0$\pm$0.1 | 58.4 | 17.9
-60.0 | -30.0 | 1.3$\pm$0.1 | 56.5 | 21.5 | 3.0$\pm$0.1 | 63.0 | 20.2 | 10.3$\pm$0.1 | 63.4 | 22.6
30.0 | -60.0 | 1.7$\pm$0.1 | 58.2 | 21.5 | 1.3$\pm$0.1 | 60.6 | 19.1 | 4.0$\pm$0.1 | 59.2 | 13.0
-30.0 | -60.0 | 5.1$\pm$0.1 | 56.0 | 20.5 | 4.0$\pm$0.1 | 63.4 | 19.8 | 20.5$\pm$0.1 | 61.1 | 22.6
-90.0 | 0.0 |  $\leq$ 0.2 | 58.2 | 0.0 | 1.3$\pm$0.1 | 63.9 | 22.4 | 4.0$\pm$0.1 | 68.2 | 19.6
0.0 | 90.0 | 0.4$\pm$0.0 | 58.7 | 17.2 | 3.0$\pm$0.1 | 62.1 | 20.9 | 11.1$\pm$0.1 | 61.2 | 19.6
0.0 | -90.0 | 2.6$\pm$0.1 | 55.0 | 17.2 | 3.0$\pm$0.1 | 58.8 | 17.3 | 15.6$\pm$0.1 | 56.9 | 21.1
60.0 | 90.0 |  $\leq$ 0.2 | 60.1 | 22.5 | 2.3$\pm$0.1 | 60.4 | 22.1 | 9.8$\pm$0.1 | 61.7 | 20.6
30.0 | 90.0 |  $\leq$ 0.2 | 53.5 | 18.4 | 3.1$\pm$0.1 | 63.2 | 22.4 | 10.3$\pm$0.1 | 60.8 | 19.6
-30.0 | 90.0 |  $\leq$ 0.2 | 55.9 | 18.4 | 2.0$\pm$0.1 | 61.8 | 18.6 | 8.8$\pm$0.1 | 61.3 | 13.0
-60.0 | 90.0 |  $\leq$ 0.2 | 63.6 | 0.0 | 1.4$\pm$0.1 | 62.1 | 19.7 | 3.3$\pm$0.1 | 62.8 | 17.3
-90.0 | 90.0 |  $\leq$ 0.2 | 44.1 | 0.0 | 1.5$\pm$0.1 | 60.4 | 20.4 | 3.9$\pm$0.1 | 62.3 | 17.9
60.0 | -90.0 | 0.4$\pm$0.1 | 62.8 | 18.4 | 1.6$\pm$0.1 | 60.7 | 15.1 | 3.7$\pm$0.1 | 62.2 | 17.3
30.0 | -90.0 | 1.0$\pm$0.1 | 55.2 | 20.5 | 1.4$\pm$0.1 | 61.0 | 17.3 | 5.9$\pm$0.1 | 57.8 | 13.8
-30.0 | -90.0 | 1.7$\pm$0.1 | 55.6 | 22.5 | 3.0$\pm$0.1 | 61.3 | 18.7 | 13.4$\pm$0.1 | 59.5 | 20.1
-60.0 | -90.0 |  $\leq$ 0.2 | 63.3 | 18.4 | 1.2$\pm$0.1 | 62.1 | 20.3 | 4.4$\pm$0.1 | 60.4 | 19.6
-90.0 | -90.0 |  $\leq$ 0.2 | 56.6 | 0.0 | 0.9$\pm$0.1 | 64.3 | 14.0 | 3.0$\pm$0.1 | 59.5 | 20.6
-90.0 | 30.0 |  $\leq$ 0.2 | 67.7 | 14.5 | 2.0$\pm$0.1 | 72.7 | 17.4 | 6.2$\pm$0.1 | 71.9 | 16.6
-90.0 | 60.0 |  $\leq$ 0.2 | 63.4 | 14.5 | 1.5$\pm$0.1 | 66.1 | 18.7 | 5.5$\pm$0.1 | 69.1 | 13.8
-120.0 | 0.0 |  $\leq$ 0.3 | -78.5 | 0.0 | 1.2$\pm$0.1 | 62.1 | 24.7 | 3.7$\pm$0.1 | 64.0 | 28.8
-120.0 | 30.0 |  $\leq$ 0.2 | 58.4 | 27.6 | 2.0$\pm$0.1 | 62.8 | 22.7 | 4.9$\pm$0.1 | 63.7 | 24.0
-120.0 | 60.0 |  $\leq$ 0.2 | 53.7 | 19.5 | 1.5$\pm$0.1 | 61.1 | 19.4 | 4.0$\pm$0.1 | 60.3 | 22.1
-90.0 | -30.0 |  $\leq$ 0.2 | 57.1 | 13.0 | 1.4$\pm$0.1 | 65.5 | 20.2 | 3.7$\pm$0.1 | 64.0 | 16.6
-120.0 | -30.0 |  $\leq$ 0.2 | 54.5 | 0.0 | 0.9$\pm$0.1 | 68.3 | 24.5 | 3.0$\pm$0.1 | 62.4 | 31.3
-90.0 | -60.0 |  $\leq$ 0.2 | 54.6 | 18.4 | 0.9$\pm$0.1 | 64.0 | 16.2 | 2.8$\pm$0.1 | 62.8 | 9.2
-120.0 | -60.0 |  $\leq$ 0.2 | 60.8 | 22.5 |  $\leq$ 0.2 | 59.1 | 24.2 | 1.8$\pm$0.1 | 61.9 | 19.6
0.0 | 120.0 |  $\leq$ 0.2 | 61.6 | 27.6 | 1.0$\pm$0.1 | 61.0 | 19.6 | 5.6$\pm$0.1 | 49.5 | 38.0
30.0 | 120.0 |  $\leq$ 0.3 | 51.1 | 27.6 | 1.1$\pm$0.2 | 58.8 | 33.4 | 5.9$\pm$0.1 | 49.8 | 38.0
60.0 | 120.0 |  $\leq$ 0.3 | 55.0 | 47.7 | 1.3$\pm$0.1 | 61.5 | 23.5 | 3.9$\pm$0.1 | 59.2 | 24.0
90.0 | 90.0 |  $\leq$ 0.2 | 56.5 | 42.6 | 1.0$\pm$0.1 | 57.8 | 15.4 | 3.4$\pm$0.1 | 57.7 | 13.8
90.0 | 60.0 |  $\leq$ 0.2 | 0.0 | 0.0 | 1.7$\pm$0.1 | 58.9 | 28.2 | 0.0$\pm$0.0 | 53.5 | 25.3
90.0 | 120.0 |  $\leq$ 0.2 | 49.6 | 0.0 |  $\leq$ 0.2 | 60.3 | 13.1 | 2.2$\pm$0.1 | 61.5 | 16.0
-30.0 | -120.0 | 0.6$\pm$0.1 | 54.8 | 22.5 | 1.3$\pm$0.1 | 58.9 | 20.6 | 5.8$\pm$0.1 | 60.0 | 21.1
0.0 | -120.0 | 1.2$\pm$0.1 | 51.9 | 17.2 | 2.4$\pm$0.1 | 58.4 | 18.6 | 12.0$\pm$0.1 | 57.2 | 16.0
30.0 | -120.0 | 0.8$\pm$0.1 | 50.1 | 18.4 | 1.5$\pm$0.1 | 56.1 | 11.6 | 8.4$\pm$0.1 | 55.7 | 10.3
60.0 | 60.0 | 0.9$\pm$0.1 | 61.5 | 17.2 | 3.4$\pm$0.1 | 63.8 | 19.8 | 13.2$\pm$0.1 | 61.8 | 22.1
0.0 | 0.0 | 22.3$\pm$0.2 | 61.7 | 15.9 | 0.0$\pm$0.0 | 67.8 | 6.7 | 0.0$\pm$0.0 | 61.5 | 0.0
-60.0 | 60.0 |  $\leq$ 0.3 | 64.9 | 25.2 | 2.3$\pm$0.1 | 67.8 | 18.7 | 5.9$\pm$0.1 | 68.8 | 13.0
60.0 | -60.0 | 0.8$\pm$0.1 | 56.7 | 22.5 | 1.7$\pm$0.1 | 57.4 | 17.5 | 4.5$\pm$0.1 | 58.0 | 17.9
30.0 | 150.0 |  $\leq$ 0.2 | 63.4 | 0.0 |  $\leq$ 0.3 | 61.7 | 14.6 | 0.8$\pm$0.1 | 60.3 | 11.3
60.0 | -120.0 |  $\leq$ 0.2 | 53.9 | 26.0 | 1.5$\pm$0.1 | 58.3 | 18.6 | 3.6$\pm$0.1 | 57.4 | 16.0
0.0 | -150.0 |  $\leq$ 0.2 | 58.6 | 20.5 | 1.4$\pm$0.1 | 60.3 | 16.1 | 7.3$\pm$0.1 | 60.1 | 18.5
30.0 | -150.0 |  $\leq$ 0.2 | 52.4 | 18.4 | 1.0$\pm$0.1 | 56.1 | 12.9 | 6.7$\pm$0.1 | 55.6 | 15.3
0.0 | -180.0 |  $\leq$ 0.2 | 55.6 | 22.5 | 1.8$\pm$0.1 | 55.2 | 16.5 | 5.9$\pm$0.1 | 55.5 | 14.6
30.0 | -180.0 |  $\leq$ 0.2 | 50.7 | 11.3 | 1.0$\pm$0.1 | 52.6 | 14.2 | 4.4$\pm$0.1 | 51.7 | 14.6
0.0 | -48.0 | 7.2$\pm$0.1 | 59.6 | 17.2 | 0.9$\pm$0.1 | 63.6 | 18.4 | 0.0$\pm$0.0 | 54.4 | 33.3

Table A2: The integrated intensities, the first moment (vm1, the intensity-weighted velocity) and second moment ($\sigma_{m2},$the intensity-weighted velocity dispersion) of the transitions of HCONH2.  rac | dec | 41,3-31,2 | 42,2-32,1 | 42,3-32,2
---|---|---|---|---
|  | intensity | vm1 | $\sigma_{m2}$ | intensity | vm1 | $\sigma_{m2}$ | intensity | vm1 | $\sigma_{m2}$
″ | ″ | K km s-1 | km s-1 | km s-1 | K km s-1 | km s-1 | km s-1 | K km s-1 | km s-1 | km s-1
-60.0 | -60.0 | 9.7$\pm$0.1 | 63.1 | 22.2 | 2.9$\pm$0.1 | 61.7 | 14.5 | 3.0$\pm$0.1 | 62.9 | 15.9
30.0 | 0.0 | 6.6$\pm$0.1 | 69.7 | 23.1 | 3.0$\pm$0.1 | 69.8 | 23.4 | 2.9$\pm$0.1 | 70.0 | 24.3
-30.0 | 0.0 | 19.8$\pm$0.1 | 69.7 | 19.4 | 9.2$\pm$0.1 | 68.5 | 13.0 | 9.0$\pm$0.1 | 68.6 | 19.5
0.0 | 30.0 | 13.4$\pm$0.1 | 69.0 | 22.2 | 5.2$\pm$0.1 | 68.2 | 19.4 | 5.1$\pm$0.1 | 68.5 | 19.5
0.0 | -30.0 | 13.7$\pm$0.1 | 63.5 | 25.5 | 10.0$\pm$0.1 | 63.0 | 24.3 | 9.9$\pm$0.1 | 63.1 | 21.6
-30.0 | 30.0 | 14.0$\pm$0.1 | 68.4 | 18.3 | 4.6$\pm$0.1 | 67.9 | 15.9 | 4.7$\pm$0.0 | 68.4 | 17.2
-30.0 | -30.0 | 25.0$\pm$0.1 | 64.4 | 24.7 | 11.8$\pm$0.1 | 62.9 | 17.1 | 12.3$\pm$0.1 | 63.9 | 22.5
30.0 | 30.0 | 12.8$\pm$0.1 | 68.9 | 22.6 | 4.5$\pm$0.1 | 67.0 | 24.3 | 4.3$\pm$0.1 | 68.8 | 21.6
30.0 | -30.0 | 6.0$\pm$0.1 | 65.1 | 20.8 | 3.2$\pm$0.1 | 65.8 | 14.5 | 3.5$\pm$0.1 | 66.4 | 17.2
0.0 | 60.0 | 14.3$\pm$0.1 | 68.8 | 21.3 | 4.2$\pm$0.1 | 68.5 | 17.1 | 4.1$\pm$0.1 | 69.5 | 24.3
60.0 | 0.0 | 3.3$\pm$0.1 | 63.6 | 28.1 | 1.0$\pm$0.1 | 64.9 | 13.0 | 0.9$\pm$0.1 | 66.9 | 26.0
-60.0 | 0.0 | 10.9$\pm$0.1 | 67.4 | 21.3 | 3.1$\pm$0.1 | 67.2 | 20.5 | 3.1$\pm$0.1 | 67.3 | 24.3
0.0 | -60.0 | 17.0$\pm$0.1 | 60.4 | 16.6 | 10.2$\pm$0.1 | 61.4 | 17.1 | 9.9$\pm$0.1 | 61.4 | 14.5
30.0 | 60.0 | 17.1$\pm$0.1 | 68.3 | 20.3 | 5.0$\pm$0.1 | 67.4 | 20.5 | 5.1$\pm$0.1 | 69.0 | 19.5
-30.0 | 60.0 | 8.1$\pm$0.1 | 66.8 | 18.8 | 2.3$\pm$0.1 | 67.0 | 18.3 | 2.2$\pm$0.1 | 66.4 | 20.6
60.0 | 30.0 | 6.6$\pm$0.1 | 63.7 | 20.3 | 1.9$\pm$0.0 | 63.7 | 17.1 | 1.8$\pm$0.1 | 64.2 | 19.5
-60.0 | 30.0 | 11.3$\pm$0.1 | 68.6 | 20.3 | 3.2$\pm$0.1 | 68.0 | 11.2 | 3.0$\pm$0.1 | 68.0 | 20.6
60.0 | -30.0 | 3.9$\pm$0.1 | 58.0 | 20.3 | 1.3$\pm$0.1 | 59.2 | 17.1 | 1.4$\pm$0.1 | 60.2 | 22.5
-60.0 | -30.0 | 12.7$\pm$0.1 | 63.4 | 22.2 | 4.1$\pm$0.1 | 62.2 | 20.5 | 4.0$\pm$0.1 | 63.0 | 19.5
30.0 | -60.0 | 6.5$\pm$0.1 | 59.8 | 21.3 | 2.8$\pm$0.1 | 60.9 | 18.3 | 2.6$\pm$0.1 | 60.7 | 19.5
-30.0 | -60.0 | 26.4$\pm$0.1 | 61.4 | 21.3 | 12.0$\pm$0.1 | 60.2 | 23.4 | 12.1$\pm$0.1 | 61.0 | 23.4
-90.0 | 0.0 | 4.2$\pm$0.1 | 67.1 | 20.3 | 1.1$\pm$0.1 | 67.0 | 14.5 | 0.9$\pm$0.1 | 66.3 | 20.6
0.0 | 90.0 | 10.8$\pm$0.2 | 61.3 | 20.8 | 2.5$\pm$0.1 | 59.4 | 20.5 | 2.3$\pm$0.1 | 60.3 | 21.6
0.0 | -90.0 | 19.4$\pm$0.1 | 57.8 | 17.2 | 6.9$\pm$0.1 | 58.0 | 19.4 | 6.8$\pm$0.1 | 58.2 | 23.4
60.0 | 90.0 | 8.2$\pm$0.2 | 60.6 | 24.3 | 2.1$\pm$0.1 | 60.3 | 23.4 | 2.0$\pm$0.1 | 62.2 | 20.6
30.0 | 90.0 | 10.7$\pm$0.2 | 60.2 | 27.0 | 2.4$\pm$0.1 | 61.0 | 19.4 | 2.3$\pm$0.1 | 61.5 | 24.3
-30.0 | 90.0 | 7.6$\pm$0.1 | 61.5 | 19.9 | 1.9$\pm$0.1 | 60.5 | 17.1 | 1.8$\pm$0.1 | 61.8 | 13.0
-60.0 | 90.0 | 4.2$\pm$0.1 | 62.4 | 19.4 | 0.9$\pm$0.1 | 63.5 | 22.5 | 0.8$\pm$0.1 | 62.6 | 22.5
-90.0 | 90.0 | 3.7$\pm$0.1 | 60.5 | 17.8 | 0.7$\pm$0.1 | 63.1 | 15.9 | 0.7$\pm$0.1 | 61.3 | 14.5
60.0 | -90.0 | 6.1$\pm$0.1 | 63.1 | 20.3 | 1.9$\pm$0.1 | 63.5 | 20.5 | 1.5$\pm$0.1 | 63.7 | 14.5
30.0 | -90.0 | 8.7$\pm$0.1 | 58.6 | 19.9 | 2.6$\pm$0.1 | 58.9 | 19.4 | 2.6$\pm$0.1 | 59.3 | 20.6
-30.0 | -90.0 | 16.2$\pm$0.1 | 60.4 | 21.3 | 5.6$\pm$0.1 | 59.8 | 19.4 | 5.3$\pm$0.1 | 59.7 | 19.5
-60.0 | -90.0 | 5.2$\pm$0.1 | 63.5 | 21.7 | 1.2$\pm$0.1 | 63.7 | 9.2 | 1.2$\pm$0.1 | 61.5 | 17.2
-90.0 | -90.0 | 2.7$\pm$0.1 | 65.2 | 19.4 | 0.5$\pm$0.1 | 63.2 | 18.3 | 0.6$\pm$0.1 | 62.5 | 20.6
-90.0 | 30.0 | 6.3$\pm$0.1 | 71.3 | 20.8 | 1.3$\pm$0.1 | 71.0 | 9.2 | 1.3$\pm$0.1 | 71.2 | 17.2
-90.0 | 60.0 | 5.7$\pm$0.1 | 68.4 | 18.3 | 1.2$\pm$0.1 | 69.0 | 9.2 | 1.0$\pm$0.1 | 69.4 | 11.3
-120.0 | 0.0 | 4.0$\pm$0.1 | 64.3 | 27.7 | 0.8$\pm$0.1 | 66.1 | 26.7 | 0.7$\pm$0.1 | 64.6 | 24.3
-120.0 | 30.0 | 5.1$\pm$0.1 | 63.6 | 21.3 | 1.2$\pm$0.1 | 63.2 | 23.4 | 0.9$\pm$0.1 | 67.4 | 25.2
-120.0 | 60.0 | 3.7$\pm$0.1 | 62.0 | 19.9 | 0.8$\pm$0.1 | 62.5 | 14.5 | 0.7$\pm$0.1 | 61.3 | 23.4
-90.0 | -30.0 | 4.2$\pm$0.1 | 64.0 | 19.9 | 1.1$\pm$0.1 | 64.5 | 11.2 | 1.0$\pm$0.1 | 60.7 | 20.6
-120.0 | -30.0 | 2.8$\pm$0.1 | 63.7 | 30.1 |  $\leq$ 0.2 | 67.0 | 15.9 |  $\leq$ 0.3 | 68.8 | 9.2
-90.0 | -60.0 | 3.5$\pm$0.1 | 63.1 | 17.8 | 0.8$\pm$0.1 | 64.3 | 14.5 | 0.6$\pm$0.1 | 62.9 | 11.3
-120.0 | -60.0 | 2.2$\pm$0.1 | 63.0 | 20.3 |  $\leq$ 0.2 | 56.5 | 13.0 |  $\leq$ 0.2 | 63.9 | 24.3
0.0 | 120.0 | 4.0$\pm$0.1 | 55.0 | 28.1 | 0.6$\pm$0.1 | 60.2 | 18.3 | 0.7$\pm$0.1 | 59.2 | 15.9
30.0 | 120.0 | 3.3$\pm$0.1 | 61.7 | 18.8 | 0.7$\pm$0.1 | 46.9 | 29.0 | 0.7$\pm$0.1 | 58.7 | 17.2
60.0 | 120.0 | 2.8$\pm$0.1 | 58.7 | 20.8 | 0.4$\pm$0.1 | 49.4 | 0.0 | 0.6$\pm$0.1 | 57.3 | 13.0
90.0 | 90.0 | 3.9$\pm$0.1 | 59.4 | 21.7 | 0.7$\pm$0.1 | 58.1 | 9.2 | 0.7$\pm$0.1 | 60.8 | 20.6
90.0 | 60.0 | 5.9$\pm$0.1 | 57.7 | 32.0 | 1.2$\pm$0.1 | 57.1 | 28.3 | 1.3$\pm$0.1 | 59.1 | 29.8
90.0 | 120.0 | 2.0$\pm$0.1 | 61.4 | 11.7 |  $\leq$ 0.2 | 62.2 | 13.0 | 0.4$\pm$0.1 | 61.3 | 0.0
-30.0 | -120.0 | 6.0$\pm$0.1 | 60.0 | 18.8 | 1.9$\pm$0.1 | 58.4 | 18.3 | 1.5$\pm$0.1 | 58.2 | 17.2
0.0 | -120.0 | 12.6$\pm$0.1 | 57.9 | 16.0 | 3.1$\pm$0.1 | 56.8 | 15.9 | 3.3$\pm$0.1 | 57.0 | 15.9
30.0 | -120.0 | 9.0$\pm$0.1 | 56.1 | 11.7 | 2.3$\pm$0.1 | 55.3 | 0.0 | 2.2$\pm$0.1 | 55.7 | 13.0
60.0 | 60.0 | 13.4$\pm$0.1 | 64.0 | 22.9 | 3.7$\pm$0.0 | 63.9 | 21.5 | 3.4$\pm$0.1 | 64.5 | 14.5
0.0 | 0.0 | 15.4$\pm$0.1 | 64.7 | 13.7 | 18.4$\pm$0.2 | 65.6 | 11.2 | 17.0$\pm$0.1 | 65.2 | 11.3
-60.0 | 60.0 | 7.0$\pm$0.1 | 67.9 | 19.1 | 2.1$\pm$0.0 | 67.8 | 20.5 | 1.6$\pm$0.1 | 69.8 | 13.0
60.0 | -60.0 | 7.0$\pm$0.1 | 59.2 | 20.1 | 2.3$\pm$0.0 | 60.9 | 19.4 | 2.0$\pm$0.1 | 59.7 | 11.3
30.0 | 150.0 | 1.3$\pm$0.1 | 61.7 | 30.4 |  $\leq$ 0.2 | 60.0 | 0.0 |  $\leq$ 0.2 | -72.2 | 0.0
60.0 | -120.0 | 5.5$\pm$0.1 | 57.3 | 23.5 | 1.4$\pm$0.1 | 58.7 | 11.2 | 1.2$\pm$0.1 | 57.7 | 18.4
0.0 | -150.0 | 8.5$\pm$0.1 | 62.2 | 23.1 | 2.0$\pm$0.1 | 60.5 | 18.3 | 1.8$\pm$0.1 | 60.8 | 9.2
30.0 | -150.0 | 6.9$\pm$0.1 | 56.1 | 14.7 | 1.6$\pm$0.1 | 56.2 | 9.2 | 1.4$\pm$0.1 | 56.0 | 15.9
0.0 | -180.0 | 6.3$\pm$0.1 | 55.7 | 19.4 | 1.3$\pm$0.1 | 55.2 | 19.4 | 1.6$\pm$0.1 | 56.3 | 22.5
30.0 | -180.0 | 4.6$\pm$0.1 | 52.3 | 18.3 | 0.9$\pm$0.1 | 52.4 | 13.0 | 0.9$\pm$0.1 | 52.3 | 13.0
0.0 | -48.0 | 9.4$\pm$0.2 | 61.5 | 28.4 | 8.6$\pm$0.1 | 61.7 | 18.3 | 8.6$\pm$0.1 | 61.5 | 13.0

Figure A1: The rotation diagrams of HCONH2 of positions with HCONH22 43-32
stronger than 3 $\sigma$. The error bar is given at 1 $\sigma$ level. HCONH2
11,1-00,0 is labeled as an orange square, while other transitions are labeled
as blue circles.

Figure A2: The rotation diagrams of HCONH2 of positions where HCONH2 43-32 is
not detected. The error bar is given at 1 $\sigma$ level. The downward arrow
represents the upper limit of intensity. HCONH2 11,1-00,0 is labeled as an
orange square, while other transitions are labeled as blue circles.

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