# ALMA Observations of the Extraordinary Carina Pillars: A Complementary
Sample

Geovanni Cortes-Rangel  Instituto de Radioastronomía y Astrofísica,
Universidad Nacional Autónoma de México,
P.O. Box 3-72, 58090, Morelia, Michoacán, México.  Luis A. Zapata  Instituto
de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México,
P.O. Box 3-72, 58090, Morelia, Michoacán, México.  Pedro R. Rivera-Ortiz
Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de
México,
P.O. Box 3-72, 58090, Morelia, Michoacán, México.  Megan Reiter  Department of
Physics and Astronomy, Rice University, 6100 Main St - MS 108, Houston, TX
77005, USA  Satoko Takahashi  National Astronomical Observatory of Japan,
2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan  Department of Astronomical
Science, The Graduate University for Advanced Studies (SOKENDAI), 2-21-1,
Osawa, Mitaka, Tokyo 181-8588, Japan  Josep M. Masqué  Departamento de
Astronomía, Universidad de Guanajuato, Apartado Postal 144, 36000, Guanajuato,
Guanajuato, México

###### Abstract

We present a study of six dusty and gaseous pillars (containing the HH 1004
and HH 1010 objects) and globules (that contain the HH 666, HH 900, HH 1006,
and HH 1066 objects) localized in the Carina nebula using sensitive and high
angular resolution ($\sim$0.3′′) Atacama Large Millimeter/Sub-millimeter Array
(ALMA) observations. This is a more extensive study that the one presented in
Cortes-Rangel et al. (2020). As in this former study, we also analyzed the 1.3
mm continuum emission and C18O(2$-$1), N2D+(3$-$2) and 12CO(2$-$1) spectral
lines. These new observations revealed the molecular outflows emanating from
the pillars, the dusty envelopes$+$disks that are exciting them, and the
extended HH objects far from their respective pillars. We reveal that the
masses of the disks$+$envelopes are in a range of 0.02 to 0.38 M⊙, and those
for the molecular outflows are of the order of 10-3 M⊙, which suggests that
their exciting sources might be low- or intermediate-mass protostars as
already revealed in recent studies at infrared and submillimeter bands. In the
regions associated with the objects HH 900 and HH 1004, we report multiple
millimeter continuum sources, from where several molecular outflows emanate.

molecular data – techniques: interferometric – ISM: individual objects (HH
666, HH 900, HH 1004, HH 1006, HH 1010 and HH 1066) – ISM: jets and outflows

##  1 Introduction

Carina, or NGC 3372, contains two very large and massive star clusters known
as Trumpler 14 (Tr14) and Trumpler 16 (Tr16) that produce large amounts of
ionizing light at UV wavelengths. These two massive clusters together contain
dozens of O-type stars on the main sequence that reach bolometric luminosities
surpassing the 107 L⊙ (Smith & Brooks, 2008). All this radiation permeates the
vicinity of the nebula revealing the well-known irradiated dusty pillars,
protoplanetary disks, and jets (Reiter & Smith, 2013; Reiter et al., 2019,
2020a). Therefore, this is an ideal nebula with extreme conditions to study
the formation of new generations of stars in such harsh environments.

Recently, Cortes-Rangel et al. (2020) presented a study using 1.3 mm continuum
and C18O(2$-$1), N2D+(3$-$2), 13CS(5$-$4), 12CO(2$-$1) spectral lines obtained
from Atacama Large Millimeter/Sub-millimeter Array (ALMA) observations of the
Carina Pillars HH 901 and 902. These observations revealed the outflows and
the dusty compact disks that are exciting the extended and irradiated Herbig-
Haro (HH) objects far from the pillars, and they estimated that the pillars
would be photoevaporated in timescales between 104 and 105 yr by the massive
stars mainly localized in Tr14 and Tr16. In addition, the circumstellar disks
associated with the HH objects 901/902 would be likely exposed to the strong
UV radiation soon after these scales of time, so they will transform into
proplyds, like those observed in other star forming regions like in Orion
(O’dell et al., 1993; Henney & O’Dell, 1999). In an even more recent study,
Reiter et al. (2020a) also presented sensitive and high angular resolution
ALMA observations of the tadpole, a relatively small, and strongly irradiated
globule inside the Carina Nebula which surrounds the HH 900 object. The ALMA
observations obtained in Cortes-Rangel et al. (2020) for the HH 901/902,
revealed the disk and outflow system inside of the pillars. For this object,
Reiter et al. (2020a) reported a timescale for the photoevaporation of $\sim$
4 $\times$ 106 yr, an order of magnitude larger than the dynamical age
determined for HH 902 Cortes-Rangel et al. (2020), a pillar closer to the
Trumpler clusters.

Figure 1: A combined (optical$+$radio) HST and ALMA image is shown for the
globule HH 666. The optical image, in green, is the H$\alpha$ emission and is
showing extended optical jet, and obscured globule that houses the
protostellar source. It also shows a millimeter continuum image at 1.3 mm
frequency (white contours). The upper right panel shows the zoom image. The
1.3 mm continuum sources are denoted by white contours. The contour levels
correspond to 10% to 90% of the peak flux with a step of 10%. The blue and red
colors show the moment zero images obtained from CO(2$-$1) emission with the
velocity range of -10.19 to -10.83 km s-1 for the redshifted emission, and
from $-$11.46 to $-$18.45 km s-1 for the blueshifted emission. The peak of the
millimeter continuum emission is 5.87 mJy beam-1 but there is still extended
emission at lower levels. The local standard rest (LSR) system velocity of the
globule is about $-$10 km s-1. The white arrows indicate the directions where
the star clusters Tr 14 and Tr 16 are located.

Both ALMA studies are an important success in revealing the disk-outflow
systems that are tremendously embedded in gas$+$dust contained in the globule
HH 900 and pillars HH 901 and 902 that cannot be studied at optical or
infrared wavelengths. Therefore, we present a complementary study using the
ALMA that includes the pillars and globules containing the objects in the
Carina Nebula: HH 666, HH 900, HH 1004, HH 1006, HH 1010, and HH 1066. This
study allows us to reveal the exciting sources of the HH objects, estimate
with more accuracy their physical conditions, and study how such harsh
environments affect their evolution, and, in particular, constrain the
formation of planets inside of the circumstellar disks.

Source | Position | Deconvolved Size | Flux | RMS111The theoretical rms for all sources is 0.046 mJy. |
---|---|---|---|---|---
|  | $\alpha_{2000}$ | $\delta_{2000}$ | $\theta_{maj}$ | $\theta_{min}$ | P.A. | Peak | Integrated | Observed |
|  | [h:m:s] | [∘ ′ ′′ ] | [milliarcsecond] | [milliarcsecond] | [∘] | [mJy beam-1] | [mJy] | [mJy] |
HH 666 |  | 10:43:51.532 | -59:55:21.18 | 85.2 $\pm$ 4.6 | 68.60 $\pm$ 3.5 | 31 $\pm$ 12 | 5.87 $\pm$ 0.17 | 14.94 $\pm$ 0.57 | 0.071 |
HH 900 A |  | 10:45:19.301 | -59:44:22.53 | 576 $\pm$ 52 | 396 $\pm$ 42 | 155 $\pm$ 12 | 2.41 $\pm$ 0.14 | 8.37 $\pm$ 0.61 | 0.043 |
HH 900 B |  | 10:45:18.797 | -59:44:23.79 | 272 $\pm$ 52 | 109 $\pm$ 70 | 62 $\pm$ 17 | 0.75 $\pm$ 0.04 | 1.09 $\pm$ 0.09 | 0.043 |
HH 1004 A |  | 10:46:44.989 | -60:10:14.73 | 101 $\pm$ 9 | 62 $\pm$ 17.5 | 153 $\pm$ 13 | 3.51 $\pm$ 0.13 | 7.42 $\pm$ 0.38 | 0.053 |
HH 1004 B |  | 10:46:44.808 | -60:10:21.20 | 61 $\pm$ 30 | 44 $\pm$ 22 | 177 $\pm$ 71 | 0.62 $\pm$ 0.06 | 0.90 $\pm$ 0.15 | 0.053 |
HH 1004 C |  | 10:46:44.969 | -60:10:15.12 | 36 $\pm$ 14 | 17 $\pm$ 18 | 178 $\pm$ 49 | 1.32 $\pm$ 0.04 | 1.49 $\pm$ 0.09 | 0.053 |
HH 1006 |  | 10:46:32.902 | -60:03:53.84 | 1139 $\pm$ 89 | 945 $\pm$ 75 | 43 $\pm$ 17 | 0.38 $\pm$ 0.02 | 9.41$\pm$ 0.73 | 0.050 |
HH 1010 |  | 10:41:48.640 | -59:43:38.04 | point source | point source | $-$ | 3.96 $\pm$ 0.09 | 4.12 $\pm$ 0.17 | 0.097 |
HH 1066 |  | 10:44:05.395 | -59:29:40.24 | 373 $\pm$ 85 | 211 $\pm$ 92 | 170 $\pm$ 26 | 1.37 $\pm$ 0.18 | 3.86 $\pm$ 0.66 | 0.053 |

Table 1: Physical parameters of the protoplanetary disks $+$ envelopes
detected in Carina from 1.3 mm continuum images for different sources using
the reduced ALMA data.

##  2 Observations and data reduction

The observations of the pillars and protostellar objects (HH 666, HH 900, HH
1004, HH 1006, HH 1010, and HH 1066) were performed with the Atacama Large
Millimeter/sub-millimeter Array (ALMA) at Band 6 in 2018 January 1 and 4
(C43-6), and April 20 (C43-3) as part of the Cycle 5 program 2017.1.00912.S.
Forty three antennas with diameters of 12 m were used for the observations,
yielding baselines from 15 $-$ 2516 m (11.5 $-$ 1935 k$\lambda$) for C43-6
configuration and 15 $-$ 500 m (11.5 $-$ 384.6 k$\lambda$) for C43-3
configuration. The primary beam at this frequency has a full width at half-
maximum (FWHM) of about 25′′, covering well the bulk of molecular and dusty
emission from the pillars.

The 1.3 mm continuum and molecular line images were obtained from the two
configurations, C43-6 and C43-3, that had source integration times of 9 and
3.5 min, respectively. We used four spw that were centered at the frequencies,
218.014 GHz(spw0) for 1.3 mm continuum and 219.578 GHz(spw1), 231.239
GHz(spw2), and 230.556 GHz(spw3) for line analysis. The channel widths were
21.486 km s-1 for the continuum and 333.328, 633.038 and 634.912 m s-1 for the
C18O, N2D+ and CO respectively. The total bandwidth for the continuum is about
4.3 GHz. Three molecular lines of C18O(2$-$1) ($\nu_{\mathrm{rest}}$=
219.56035 GHz), N2D+(3$-$2) ($\nu_{\mathrm{rest}}$=231.31990) and 12CO(2$-$1)
($\nu_{\mathrm{rest}}$=230.53800 GHz) were observed in spw1, spw2 and spw3,
respectively. System temperatures were between 100 to 150 K and precipitable
water vapor was between 1.3 mm and 2.2 mm. The ALMA calibration included
simultaneous observations of the 183 GHz water line with water vapor
radiometers, used to reduce atmospheric phase fluctuations. Quasars,
J0904-5735, and J1107-4449 were used for the band-pass and flux calibrations.
J1032-5917 was used for correcting the gain fluctuations.

The data reduction was done using the Common Astronomy Software Applications
(CASA, CASA Team et al., 2022) version 5.1. We concatenated the data from both
configurations (C43-6 and C43-3) with the UVCONCAT task. Imaging of the
calibrated visibilities was done using the TCLEAN task. We used the briggs
weighting (robust = 0.5) in the TCLEAN task to obtain the continuum and
spectral lines images. We report the parameters obtained from a two-
dimensional Gaussian fit in CASA to the continuum images at 1.3 mm, using the
gaussfit tool (within the CASA viewer), which subtracts the sky component to a
selected region for the emission distribution. We obtained the deconvolved
sizes from the synthesized beam of each image and this Gaussian fit. The
results of the physical parameters (position, deconvolved size, flux, and rms)
are shown in Table 1. We attempted self-calibration on the continuum emission,
but unfortunately, the resulting maps did not improve significantly. Thus, we
stick with the non-self-calibrated maps.

##  3 Results and Discussion

Our data reveal for the first time the bipolar molecular outflows emerging
from HH 666/1004/1006/1010 and 1066 YSOs (Young Stellar Objects) which
corresponds very well to the optical jets previously studied by Hubble Space
Telescope (HST) using the Advanced Camera for Surveys (ACS) (see Figures 1, 2,
4, 5, 7 and 9). In the following subsections, we show the analysis for each
separate object. We show their gas and dust structures obtained with the ALMA
observations together with some estimated physical values, such as fluxes,
masses, sizes, and the comparison with their respective optical and infrared
bulk emissions. The parameters obtained from the observations and the
reduction of the data carried out with CASA are shown in Table 1.

###  3.1 HH 666

The HH 666 object, known as the axis of evil, was first reported by Smith et
al. (2004) using ground-based optical and near-IR (infrared) observations that
revealed the bipolar flow emerging from the head of a dusty globule pointing
in the direction of $\eta$ Carinae and Tr 16. A protostar (listed as Class I
object) embedded within the dense globule is proposed as the possible driving
source of the optical jet (detected at the center of the globule at the
position in the sky of $\alpha=10^{h}43^{m}51^{s}.3$,
$\delta=-59^{\circ}55^{\prime}21^{\prime\prime}.2$, J2000), see Smith et al.
(2004). In a later study, Smith et al. (2010) reported new H$\alpha$
observations from the HST, corroborating the jet structure associated with the
HH object, the extension of jet component ($\sim$4′.5 or $\sim$3 pc), and the
detection of a weak object located at the same position as the previous study.
This object was also detected in Spitzer near-IR observations (Smith et al.,
2010)

In recent work, Reiter et al. (2015a) presented near-IR spectroscopic studies
of [Fe II] obtained with the Folded-Port InfraRed Echelette (FIRE)
spectrograph on the Baade/Magellan Telescope. These observations reveal that
[Fe II] emission is tracing a highly collimated protostellar jet embedded in
the dense pillar of gas and dust with an extension of about 40 arcsecs. They
also found a clear connection between the previously revealed jet driving
source and the extent of the collimated jet. Finally, their studies of [Fe II]
and H$\alpha$ showed differences, especially in areas very close to the
protostellar source, where the images in H$\alpha$ did not reveal any
emission.

In Figure 1, we present the optical image of the HST/ACS presented in Smith et
al. (2010) overlaid with our resulting ALMA 1.3 mm continuum and line images
of the globule HH 666. The optical image (green) corresponds to H$\alpha$
emission and is overlapped with the ALMA high velocity CO(2$-$1) molecular
emission (blue and red) and the 1.3 mm continuum emission (white contours).
The CO emission is tracing the bipolar outflow very close to the exciting
source, which moves at an LSR system velocity of $-$10 km s-1. The angular
size is 1.6′′ which at 2.3 kpc represents a size of 3680 au for HH 666.

The 1.3 mm continuum emission is only located in the axis of the optical jet
detected in H$\alpha$ at $\alpha=10^{h}43^{m}51^{s}.5$,
$\delta=-59^{\circ}55^{\prime}21^{\prime\prime}.1$ (J2000), perfectly matching
the near-IR source detected by (Smith et al., 2004) (see Figure 1) and reveals
a compact source corresponding to an embedded structure in the central zone of
the globule. We think that this object is composed of a dusty envelope and
circumstellar disk corresponding to the driving source of the protostellar
optical jet, and for this millimeter continuum emission, we obtained an
integrated flux of 14.94 $\pm$ 0.57 mJy and an observed rms noise of 0.071 mJy
(see Table 1) for the continuum image, which is very close to the theoretical
noise value for this configuration (43 antennas), frequency (230 GHz),
bandwidth (4.3 GHz) and integration time (12.5 min.) and is 0.046 mJy. From a
Gaussian fit in CASA for the continuum source and the synthesized beam size
(0′′.07 $\times$ 0′′.05), we obtained a deconvolved size of 0′′.0852 $\pm$
0′′.0046 $\times$ 0′′.0686 $\pm$ 0′′.0035 with an PA of 31∘ $\pm$ 12∘, that
corresponds to an approximate physical size of 200 au $\times$ 150 au, which
is according to the physical sizes of the protoplanetary disks ($\sim$100 au).

From this detected dust emission, we can estimate the total mass for these
structures, even for the case of component B, which is much fainter than
component A. At millimeter wavelengths, the emission can be assumed to be
optically thin, and we can then estimate the dust mass from the following
expression:

$M_{d}=\frac{D^{2}\,S_{\nu}}{\kappa_{\nu}\,B_{\nu}(T_{d})}$ (1)

where Sν is the flux density, D is the distance to the considered sources, we
assume that it is the same as the Carina Nebula (2.3$\pm$0.1 kpc, Smith &
Brooks, 2008), $\kappa_{\nu}$= 0.015 cm2 g-1 is the dust mass opacity for a
dust-to-gas ratio of 100 appropriate for 1.3 mm (Ossenkopf & Henning, 1994)
and B${}_{\nu}(T_{d})$ is the Planck function for the dust temperature Td.
Given the observing frequency of our data ($\sim$ 225 GHz), we considered the
Rayleigh-Jeans regime. We compute the values for the masses of this (and the
others) source and show them in Table 2 from the measured fluxes presented in
Table 1. For this source, we found that the dust mass associated with the
detected continuum structure ($\sim$ 15 mJy) is between 0.3$-$0.7 M${\odot}$,
assuming temperature values between 20 K and 50 K as Cortes-Rangel et al.
(2020).

Source |  Disk masses222We estimate different mass values by varying the assumed temperature to compare the mass variation. |  RMS masses333Masses estimated from image noise at 4$\sigma$. |
---|---|---|---
|  | 20 K | 40 K | 50 K |  |  |
|  |  | [M⊙] |  |  | [MJup] |
HH 666 |  | 0.77 | 0.38 | 0.30 |  | 6.14 |
HH 900 A |  | 0.43 | 0.21 | 0.17 |  | 3.72 |
HH 900 B |  | 0.05 | 0.02 | 0.02 |  | 3.72 |
HH 1004 A |  | 0.38 | 0.19 | 0.15 |  | 4.58 |
HH 1004 B |  | 0.04 | 0.02 | 0.01 |  | 4.58 |
HH 1004 C |  | 0.07 | 0.03 | 0.03 |  | 4.58 |
HH 1006 |  | 0.48 | 0.24 | 0.19 |  | 4.32 |
HH 1010 |  | 0.21 | 0.10 | 0.08 |  | 8.39 |
HH 1066 |  | 0.19 | 0.09 | 0.07 |  | 4.58 |
Table 2: Dust masses obtained by the emission detected at 1.3 mm for the
compact systems (discs+envelopes) associated to each HH object studied.

As mentioned earlier, we also show the molecular CO(2$-$1) emission
corresponding to the outflow in the HH 666 object. In Figure 1, we can see the
molecular emission plotted in blue and red colors corresponding to the
blueshifted and redshifted gas, respectively. From these maps, we only
detected CO(2$-$1) emission (blueshifted$+$redshifted) toward the western side
of the ALMA 1.3 mm continuum source, revealing a monopolar outflow, which is
associated with the extended HH 666 object. We did not detect molecular
CO(2$-$1) emission associated with the large globule itself, maybe because its
emission is either extended and complex, so our ALMA observations could not
recover quite well the extension of the globule. Another possibility is that
this is an old globule with a quite small quantity of molecular gas. Klaassen
et al. (2019) using ALMA Compact Array (ACA) observations of pillar 3
(corresponding to the HH 666 globule) reported clumpy and dispersed CO(2$-$1)
emission. Despite the larger beamsize of their observations with respect to
ours (i.e. 6 arcsec or about 20 times larger), the extended emission of the
globule was poorly recovered, we then favor the interpretation that our
observations are losing most of the extended emission.

Since the detected CO emission is faint, it is difficult to say anything about
the orientation, extension, or morphology of the molecular outflow. From
Figure 1, this appears to have a West to East orientation with mostly the
compact emission arising towards the western side. In addition, we cannot give
an estimation for the mass of the globule, and its respective outflow due to
not tracing their complete structure.

Source | Pillar/Globule |  Outflow444Red and blue superscript refer to detected redshifted and blueshifted gas. |
---|---|---|---
|  |  Iν555Average intensity for the pillar or globule. |  d$v$666Velocity range for the pillar or globule flux. |  Size777We obtain the size by multiplying $\theta_{max}\times\theta_{min}$. | Mass |  |  I${}_{\nu}^{\,red,}$888Average intensity for the outflow. I${}_{\nu}^{\,blue}$ |  d$v^{red,}$999Velocity range for the outflow flux. d$v^{blue}$ |  Sizered Sizeblue |  Mass101010It is the total mass of the outflow, that is, the sum of the mass of the redshifted and the blueshifted outflow. |  |
|  |  [ $\frac{\rm{mJy}}{\rm{beam}}$ ] |  [km s-1] |  [arcsec2] |  [M⊙] |  |  [ $\frac{\rm{mJy}}{\rm{beam}}$ ] |  [km s-1] |  [arcsec2] |  [M⊙] |  |
HH 900 |  | 60 | 2.7 | 5.2 |  4$\times 10^{-3}$ |  | 46.9 23.5 | 3 1 | 2 2 |  1.4$\times 10^{-3}$ |  |
HH 1006 |  | 50 | 3.2 | 11.4 |  7$\times 10^{-3}$ |  | 44 17.6 |  3 2.5 | 3.2 1.2 |  2.1$\times 10^{-3}$ |  |
HH 1010 |  | 50 | 2.2 | 170 |  7$\times 10^{-2}$ |  | 3.3 4 | 4 2 |  2.5 0.25 |  1.5$\times 10^{-3}$ |  |
Table 3: Gas masses obtained by the emission detected for the CO(2$-$1)
emission at 230 GHz for the pillars/globules and outflows associated with each
HH object studied. We estimate the mass using an excitation temperature of
Tex=50 K, an abundance ratio between the molecular hydrogen and CO of
$X_{\frac{H_{2}}{CO}}\sim$104, and a distance to Carina nebula of 2.3 kpc. We
only included the sources for which there was CO molecular detection. Figure
2: A combined HST (optical) $+$ ALMA (radio) image is shown for the globule HH
900. The optical image (green) is the H$\alpha$ emission about the optical jet
and obscured globule that houses the protostellar source evidenced by 1.3 mm
emission (white contours varying from 30$\%$ to 90$\%$ of the peak emission,
in steps of 10%). The peak of the millimeter continuum emission is 2.41 mJy
beam-1 for component A and 0.75 mJy beam-1 for component B. Also shown in blue
and red colors is the CO(2$-$1) moment zero for the molecular outflow
associated with the protostar (component A). Component B does not have any
associated molecular outflow. In this case, the blue color corresponds to the
blueshift molecular gas, and the red color corresponds to the redshift
molecular gas. The LSR system velocity of the globule is about $-$33.72 km
s-1. The white arrow indicates the direction where the star clusters Tr 14 and
Tr 16 are located.

###  3.2 HH 900

HH 900 is a dark globule located very close to the central zone of the Carina
Nebula, a region strongly affected by the extreme UV radiation generated by
nearby massive stars to the star cluster Trumpler 16, and the massive and
evolved variable star $\eta$ Carinae located about $\sim$3 pc from the HH 900.
It has an angular size of the order of 1′′ (equivalent to a spatial scale of
$\sim$0.01 pc). This source is also known as the tadpole due to its unusual
morphology that simulates a baby frog, made up of a dense globule (tadpole
head) followed by an elongated and compact tail that extends in the same
direction as the axis of the optical jet revealed by the images of the HST
(see Figure 2). Using these observations, Smith et al. (2010) studied the
components of the bipolar structure of the optical jet, and globule traced by
the gas emission of H$\alpha$ corresponding to externally ionized gas. The
asymmetric morphology revealed at optical wavelengths has not been explained
since it differs from the typical jet morphologies that present a collimated
and very symmetrical bipolar structure (Reipurth & Bally, 2001; Reipurth et
al., 2019; Noriega-Crespo et al., 2020). The extreme UV radiation field is
illuminating throughout the length of the protostellar jet with a projection
close to the plane of the sky and an inclination angle for the jet $\sim$ 10∘
(Reiter et al., 2015b).

They studied the high-velocity component of the protostellar jet through near-
infrared (NIR) observations for the line of [Fe II] and that, unlike the
observations of H$\alpha$, showed an external collimated jet structure that is
extending from east to west of the globule, presenting a remarkable symmetry
that argues for the fact that the driving source would have to be located
inside the center of the globule although they did not find IR emission from
the protostar inside the globule, suggesting the fact that the protostar may
be embedded inside remaining invisible due to the high column density. Shinn
et al. (2013) detected two sources associated with the HH 900 object through
observations of [Fe II] at 1.64 $\mu$m but until now, no study could
corroborate that these detected sources were generating the jets because no
direct connection was found between the extended flows and the compact sources
detected by this study (YSO also cataloged by Spitzer, Povich et al., 2011).

Subsequently, Reiter et al. (2019) studied the HH 900 source at optical
wavelengths with MUSE/VLT observations detecting several emission lines
(hydrogen recombination lines and some forbidden emission lines) that also
trace the outflow. Their observations were also unable to detect the protostar
embedded within the tadpole, although the emission was detected for different
lines that are tracing the collimated bipolar jet at different densities (for
example [Fe II], [Ca II], and [Ni II]), is emanating from the globule, which
reinforces the idea of that the protostellar source must be housed inside it.

More recently Reiter et al. (2020a) reported using ALMA observations the
bipolar molecular outflow traced by the CO emission arising from the protostar
called HH 900 YSO. The outflow is bi-conical and matches very well the overall
morphology of the optical jet. The estimated mass for the total globule is
about 2 M⊙ (from the dust continuum), which results in a lifetime of 4 Myrs of
Reiter et al. (2020a), with the assumption of a constant photo-evaporation
rate.

Our results obtained from the ALMA observations for the continuum emission at
1.3 mm reveals two compact sources called A and B (white contours in Figure
2). These two compact objects were already reported in previous ALMA
observations presented in Reiter et al. (2020a). The millimeter emission is
shown in Figure 2 as white contours and is likely associated with the dust
emission of the circumstellar envelope and flatted disk (see for example
Reiter et al. (2020a, b)). We note that the emission is located at the center
of the tadpole’s head from which emerges the bipolar molecular outflow also
detected thanks to the high angular resolution of ALMA Reiter et al. (2020a).
Our observations also revealed a second component traced by the continuum
emission (component B) located in the southeastern part of the optical jet in
the area strongly illuminated by external ultraviolet radiation. From the
Figure, we can see that there is no molecular outflow associated with this
component, maybe because this source is prestellar, as already discussed in
Reiter et al. (2020a). Reiter et al. (2019) also rejected the premise that
this detected object (named PCYC 838) was driving a microjet. They dismissed
the idea by arguing that the symmetric [Fe II] jet is centered on the globule
and not the star, in addition to the lack of evidence of different velocity
components in the reported spectra, concluded that a likely explanation is
that this object is coincidentally aligned with the observed jet.

From the continuum emission, we obtained an integrated flux of 8.37 $\pm$ 0.61
mJy and 1.09 $\pm$ 0.09 mJy for components A and B respectively, and an
observed rms noise of 0.043 mJy (see Table 1). From the synthesized beam size
(0′′.34 $\times$ 0′′.27), we obtained a deconvolved size for component A of
0′′.576 $\pm$ 0′′.052 $\times$ 0′′.396 $\pm$ 0′′.042 with an PA of 155∘ $\pm$
12∘, with an approximate physical size of 1330 $\times$ 910 au.

From the millimeter continuum emission, we estimate the dust mass associated
with the structure detected by our observations, following the equation
described in the previous subsection (1), giving values between 0.17$-$0.43
M⊙, assuming temperatures between 20 K and 50 K for the component A, which is
the component associated with the detected CO(2-1) bipolar molecular outflow
shown in red and blue colors in the Figure 2. This line emission at 230 GHz is
tracing perfectly the tail of the tadpole (blueshifted CO gas) extending along
the axis of the optical jet, just like its counterpart (redshifted CO gas). We
can deduce that the protostar is a Class 0/I object from the mass-loss rate
($\sim$ 5$\times$ 10-6 M$\odot$ yr-1) reported by Reiter et al. (2015b). The
continuum emission of this source possibly includes the disk and envelope,
which reveals the emission from the disk and the envelope around the driving
source. For component B we estimated a dust mass between 0.02$-$0.05 M⊙ under
the same assumptions.

We note in Figure 2 that the molecular outflow is aligned to the optical jet,
and expands at velocities between $-$32 and $-$36 km s-1. The flux detected in
CO is tracing the innermost parts of the dark globule connected to the extent
of the outflow with the driving source detected by the continuum emission. We
integrate LSR velocities from $-$29.27 to $-$33.08 km s-1 for the redshifted
emission oriented to the northwest, and from $-$34.99 to $-$40.70 km s-1 for
the blueshifted emission oriented to the southeast, for the CO outflow in the
HH 900 object. The molecular outflow revealed by the CO is only evident for
one component denominated component A.

Figure 3: The upper panel shows the moment zero (contours) and moment one
(colors) for CO(2$-$1), and the lower panel shows the moment zero (contours)
of CO and moment one (colors) of C18O (2$-$1) of the globule HH 900. The
contours vary in the range from 40% to 90% of the peak emission, in steps of
12%. The peak of the CO (2$-$1) emission is 0.33 Jy Beam-1 km s-1. The arrows
(blue and red) show the direction of molecular outflow expansion. The gray
circles in both figures represent the location of the compact source (system
disk$+$envelope) detected in the continuum at 1.3 mm. The LSR radial-velocity
scale bar is shown on the right.

In Figure 3, we show the emission of molecular gas for the CO(2$-$1) (top
panel) and C18O(2$-$1) (bottom panel) detected lines. The moment zero of CO is
shown in black contours for both panels of Figure 3, as a comparison between
the emission of the molecules. The moment one is shown in color scale for CO
(top panel) and for C18O (bottom panel). It is observed that CO is perfectly
tracing the globule, including the tail of the globule, hosting the compact
source detected by the continuum (gray circle) and corresponding to the
bipolar molecular outflow of CO also observed. The bipolar molecular outflow
is also evident in these maps for both panels, with a northwestern orientation
to the redshifted emission and a southeastern orientation to the blueshifted
emission. If we analyze the velocities for the molecular outflow in this map,
we note that the width velocity is $\sim$ 5 km s-1, which suggests that the
molecular flow is not a high velocity one.

The outflow extends no further than the emission detected for the rest of the
HH 900 globule (bounded by the moment zero of CO). The different velocity
components detected vary between the LSR range of $-$29.27 to $-$40.70 km s-1,
velocities that were used to integrate the moment zero (contours) and one
(colors) of the CO emission. The average LSR velocity of the cloud is $\sim$
$-$34 km s-1. The CO molecule best traces the globule as a whole, while the
C18O is evidencing more internal zones of the cloud where the protostar and
envelope are localized, and the density is higher. This image (bottom panel)
was obtained by integrating over the LSR velocity range of $-$33.23 to
$-$35.23 km s-1. The system LSR velocity of the cloud is $\sim$$-$33.90 km
s-1. For this case, the molecular emission shows a width of velocities $\sim$
1 km s-1, which confirms the result obtained with the CO map showing that
these flows are not high speed.

We compute the gas mass using the observed CO transition J=2 $\rightarrow$ 1
from the following equation:

$\begin{split}\left[\frac{M_{H_{2}}}{M_{\odot}}\right]=1.2\times
10^{-15}\,T_{\mathrm{ex}}\,e^{\frac{16.59}{T_{\mathrm{ex}}}}\,X_{\frac{H_{2}}{CO}}\left[\frac{\int\mathrm{I_{\nu}dv}}{\mathrm{Jy\,km\,s}^{-1}}\right]\\\
\quad\left[\frac{\theta_{\mathrm{maj}}\,\theta_{\mathrm{min}}}{\mathrm{arcsec}^{2}}\right]\left[\frac{D}{\mathrm{pc}}\right]^{2},\end{split}$
(2)

where $X_{\frac{H_{2}}{CO}}\sim$104 (Scoville et al., 1986) is the abundance
ratio between the molecular hydrogen (H2) and carbon monoxide (CO), Iν is the
average intensity ($I_{\nu}$) for the pillar-globule/outflow, $dv$ is the
velocity range for the pillar-globule/outflow, $D$ is the distance to the
source of 2.3$\pm$0.1 kpc and Tex is the excitation temperature taken as 50 K,
this is the highest temperature in the range used previously for the dust
temperature, and it provides an upper limit for our mass estimation.

We obtained a value for the gas mass of the tadpole globule of 4 $\times$ 10-3
M⊙ using the emission lower than $\pm$1 km s-1 from the system velocity, and
the mass of the outflow was 1.4 $\times$ 10-3 M⊙ for velocities larger than
$\pm$1 km s-1 (see table 3). The estimated values for both masses should be
considered as a lower mass limit because the medium could be optically thick.

Figure 4: A combined (optical$+$radio) HST and ALMA image is shown for the
pillar HH 1004. The optical image, in green, is the H$\alpha$ emission and is
showing the optical jet and the pillar in which the compact source detected in
the continuum at 1.3 mm is embedded and shown as white contours (varying from
15$\%$ to 90$\%$ of the peak emission, in steps of 10%). Three compact sources
were detected (components A, B, and C). The peak of the millimeter continuum
emission is 3.51 mJy Beam-1 but there is still extended emission at lower
levels. Also shown in blue and red colors is the CO(2$-$1) moment zero for the
molecular outflows associated with the compact sources. In this case, the blue
color corresponds to the blueshift molecular gas and the red color corresponds
to the redshift molecular gas. The LSR system velocity of the globule is about
$-$20 km s-1. The white arrow indicates the direction where the star cluster
Tr 16 is located.

We calculate the theoretical value of the mass photo-evaporation rate
($\dot{M}$) for the globule HH 900 associated with the driving source
following Cortes-Rangel et al. (2020) (see their equation 3). The size of the
globule was calculated using a Gaussian fitting in CASA, assuming a distance
of 2.3 kpc. In this case, the globule is affected by ultraviolet radiation
originating from the Tr 16 with a UV luminosity of (QH) = 9$\times 10^{50}$
photons s-1 (Smith & Brooks, 2008). This luminosity (QH) translates into a
flux F${}_{EUV}=8.35\times 10^{11}$ photons s-1 cm-2 assuming that the
distance from the HH 900 globule to the cluster is $\sim$ 3pc. We obtained a
mass photo-evaporation rate of 2.6$\times 10^{-5}$ M⊙ yr-1. This estimated
value is consistent with the methodology described by Reiter et al. (2015b) (7
$\times$ 10-6 M⊙ yr-1), taking into account that we have used the gas mass of
the globule (instead of the dust mass) which translates into a difference of
at least an order of magnitude in mass and a factor of $\sim$4 in size, so our
value differs by an order of magnitude than the one presented by them. In this
calculation we do not consider the optical depth value and since the globule
is very optically thick that may account for the difference. We can estimate
the photo-evaporation timescale of the globule HH 900 by dividing the
estimated gas mass for the globule (4 $\times$ 10-3 M⊙) by this mass photo-
evaporation rate, giving $\sim$ 150 yr, which will be the time in which the
globule HH 900 will be photo-evaporated by the massive stellar cluster Tr 16
(see Table 4). Using the dust mass we estimated for this globule (0.21 M⊙),
that corresponds to the whole continuum emission at 1.3 mm, the photo-
evaporation timescale would be $\sim$8000 yr, $\sim$two orders magnitude less
than the reported value reported by Reiter et al. (2020a) (4 Myr), although it
should be noted that our estimated dust mass differs by a factor of $\sim$10
and the photo-evaporation rate by a factor of $\sim$100.

Figure 5: The figure shows a combined (optical$+$radio) HST and ALMA image for the globule HH 1006. The optical image (green) is the H$\alpha$ emission and is showing optical jet and the globule in which the compact source detected in the continuum at 1.3 mm is embedded, and shown as white contours (varying from 55$\%$ to 90$\%$ of the peak emission, in steps of 10%). The peak of the millimeter continuum emission is 7.83 mJy beam-1. Also shown in blue and red colors the CO(2$-$1) moment zero for the molecular outflows associated with the compact source. In this case, the blue color corresponds to the blueshifted molecular gas and the red color corresponds to the redshifted molecular gas. The LSR system velocity of the globule is about $-$23 km s-1. The white arrow indicates the direction where the star cluster Tr 16 is located.  Source | R 111111Radius of the pillar\globule |  $\dot{M}$121212Mass photoevaporation rate |  $t$131313Photoevaphoration timescale
---|---|---|---
| [au] |  | [M⊙ yr-1] |  | [yr] |
HH 900 | 8050 |  | 2.6$\times 10^{-5}$ |  | 153 |
HH 1006 | 8740 |  | 5.7$\times 10^{-6}$ |  | 1228 |
HH 1010 | 39100 |  | 3.1$\times 10^{-5}$ |  | 2258 |
Table 4: The sizes of each pillar/globule were calculated using a Gaussian
fitting in CASA to the extended gas emission using CO (2$-$1), assuming a
distance of 2.3 kpc to each of the studied sources. Each pillar/globule is
affected by ultraviolet radiation (FEUV) originating from the nearby clusters,
Tr 14 and Tr 16, for which a UV luminosity of approximately (QH) = 2$\times
10^{50}$ photons s-1 for Tr 14 and (QH) = 9$\times 10^{50}$ photons s-1 for Tr
16 (Smith & Brooks, 2008).

###  3.3 HH 1004

This source is located in the southern region of the Carina Nebula,
specifically within the South Pillars. The pillar identified by Smith et al.
(2010) exhibits a highly elongated structure pointing towards the Tr 16
stellar cluster. This displays a clear optical bipolar jet at the tip of the
pillar, which is being strongly irradiated by the UV radiation field emanating
from the OB stars present in Tr 16. Further south of the pillar, the presence
of another bright jet is evident, expanding in a southwest direction opposite
to that of the stellar cluster. There are shock structures further away that
may potentially be associated with the same jet phenomenon, although
considering only the innermost part of the detected optical jet, a jet length
of approximately 0.4 pc is quantified.

Figure 6: Images of moment zero (contours) and moment one (colors) are
presented for the molecular emission of CO (2$-$1) (top panel), and moment one
of C18O (2$-$1) (bottom panel) of the globule of HH 1006. The Figure presents
a comparison between the CO moment zero presented in contours (varying in the
range from 1% to 90% of the peak emission, in steps of 10%), by the emission
that is best tracing the globule, with respect to the moment one of emission
for CO and C18O. The peak of the millimeter line CO emission is 0.71 Jy Beam-1
km s-1. The arrows (blue and red) show the direction of molecular outflow
expansion. The gray circles in both Figures represent the location of the
compact source (system disk$+$envelope) detected in the continuum at 1.3 mm.
The LSR radial-velocity scale bar is shown on the right.

In Figure 4, the combination of observations made with HST/ACS for the HH 1004
pillar and our observations obtained with ALMA for the continuum and CO
emission are shown. The optical image (green) corresponds to the H$\alpha$
emission and is overlapped with the ALMA high velocity CO(2$-$1) molecular
emission (blue and red), and the 1.3 mm continuum emission (white contours).
The CO(2$-$1) molecular emission was obtained by integrating in LSR velocities
from $-$15.55 to $-$4.75 km s-1 for the redshifted emission, and from $-$40.31
to $-$25.07 km s-1 for the blueshifted emission. The ALMA 1.3 mm continuum
image reveals three compact sources (A, B, and C) distributed in the northern
region of the pillar (at the head of the pillar, see Table 1). Components A
and B appear to be associated with the optical jet detected in H$\alpha$.

For this millimeter continuum emission, we obtained an integrated flux of 7.42
$\pm$ 0.38 mJy for source A, 0.90 $\pm$ 0.15 mJy for source B, and 1.49 $\pm$
0.09 mJy for source C respectively. The observed rms noise was 0.053 mJy for
the three sources, which is very close to the theoretical noise value (see
Table 1). From the synthesized beam size (0′′.11 $\times$ 0′′.06), we obtained
a deconvolved size similar to HH 666, for example, for source C we obtained a
deconvolved size of 0′′.036 $\pm$ 0′′.014 $\times$ 0′′.017 $\pm$ 0′′.018 with
an PA of 178∘ $\pm$ 49∘, that corresponds to an approximate physical size of
83 au $\times$ 40 au, consistent with the typical physical sizes of the
protoplanetary disks (Andrews, 2020).

We estimated the total masses for these structures using the equation 1 and we
obtained that the masses for components A, B, and C are between 0.15$-$0.38,
0.01$-$0.04 and 0.03$-$0.07 M⊙ respectively, assuming temperature values
between 20 to 50 K (see Table 2).

We show in the same Figure 4, the molecular CO (2$-$1) emission plotted in
blue and red colors corresponding to the blueshifted and redshifted gas,
respectively. We observe a bipolar outflow emerging from the compact continuum
source A, with the blueshifted portion extending southwest along the axis of
the optical jet detected in H$\alpha$. Very little redshifted emission is
apparent, and due to the weak flux detected at these velocities, it is not
clear whether this emission expands in the same northeast direction along the
axis of the optical jet. Source B also appears to overlap a portion of the
blueshifted molecular outflow detected, although it is difficult to discern
whether the detection of this molecular outflow is generated by both sources A
and B, or if it is solely attributed to source A, which is larger ($\sim$230
au $\times$ 140 au) and more massive (0.38 M⊙) compared to source B ($\sim$140
au $\times$ 100 au, 0.04 M⊙ mass). Compact source C exhibits a CO redshifted
molecular outflow that is more extended than the one detected for sources A
and B, although it does not display a blueshifted counterpart. This can be
explained by the inhomogeneities in the cloud. As far as we know this is the
first molecular detection for this outflow component. This source is north of
the [Fe II] emission that goes through the pillar (see Fig 6 in Reiter et al.
(2016)). This looks to be in the right place to drive the extended H$\alpha$
emission seen off the left of the pillar that Smith et al. (2010) identify as
HH 1005.

Figure 7: ALMA CO(2$-$1) moment zero (blue and red colors) and millimeter
continuum (white contours) images of the HH 1010 object overlaid in a HST
(H$\alpha$) optical image (green colors). The blue and red colors represent
the blueshifted and redshifted CO emissions, respectively, from the HH 1010
outflow. The 1.3 mm continuum emission is denoted by the white contours. The
contour levels range from 18% to 90% of the peak emission, in steps of 10%.
The peak of the millimeter continuum emission is 4.07 mJy Beam-1. Here, we are
only contouring the most compact 1.3 mm emission from our observations
revealing the envelope and the disk. We integrate in radial velocities from
$-$9.54 to $-$15.25 km s-1 for the redshifted emission, and from $-$18.43 to
$-$27.32 km s-1 for the blueshifted emission for the CO outflow in the HH 1010
object. The LSR system velocity of the entire pillar associated with the
object HH 1010 is about $-$16.52 km s-1.

Figure 8: Images of moment zero (contours) and moment one (colors) are
presented for the molecular emission of CO (2$-$1) (top panel) and the moment
one of C18O (2$-$1) (bottom panel) of the globule of HH 1010. The Figure
presents the CO moment zero emission in contours varying from 3% to 90% of the
peak emission, in steps of 10%. The peak of the millimeter line CO emission is
1.2 Jy Beam-1 km s-1. The arrows (blue and red) show the direction of
molecular outflow expansion. The gray circles in both figures represent the
location of the compact source (system disk$+$envelope) detected in the
continuum at 1.3 mm. The LSR radial-velocity scale bar is shown on the right.

###  3.4 HH 1006

This bipolar jet emerges from a small dark globule, pointing in the northern
direction of $\eta$ Carinae, and is located in the central region of the South
Pillars in the zone where these pillars are strongly irradiated by the massive
stars of Tr 16. The HH 1006 jet is formed by a chain of knots that extend
along its axis, and have an extension of $\sim$0.2 pc measured in optical
wavelengths by Smith et al. (2010), and by Sahai et al. (2012), who presented
CO (3$-$2) single dish observations, although for our study we have focused
only on the characterization of the central jet, that is, the closest to the
globule.

In Figure 5 we show an optical image of the HST in H$\alpha$ (green), and our
results obtained with the ALMA observations for the continuum emission at 1.3
mm (white contours in the Figure) and the CO molecular emission (red and blue
colors). The continuum emission reveals a compact source at the center of the
globule with an integrated flux of 9.41 $\pm$ 0.73 mJy and a PA of 43∘ $\pm$
17∘ (see Table1). From the synthesized beam size (0′′.23 $\times$ 0′′.20), we
obtained a deconvolved size of 1′′.139 $\pm$ 0.′′089 $\times$ 0.′′945 $\pm$
0′′.075, which corresponds to an approximate physical size of 2600 au $\times$
2200 au. The compact source is generating the molecular outflow that extends
along the same axis of the globule. We estimate that the mass of dust follows
again the equation (1) and is between 0.19$-$0.48 M⊙, assuming temperature
values between 20 K and 50 K. This value is an order of magnitude lower than
the estimation of 0.02 M⊙ obtained by Mesa-Delgado et al. (2016), which can be
explained by the fact that we report a larger source size. Perhaps, we are
detecting more of the envelope than they did.

The molecular outflow is detected aligned on the axis of the optical jet and
extending in the same direction of the globule axis at velocities between
$-$21 and $-$24 km s-1. This CO flux is tracing the innermost parts of the
globule connected to the extent of the outflow with the driving source. We
integrate in radial velocities from $-$17.88 to $-$21.05 km s-1 for the
redshifted emission oriented to the south, and from $-$24.23 to $-$27.40 km
s-1 for the blueshifted emission oriented to the north of the globule.

In Figure 6, we show the moment zero map obtained from CO(2$-$1) in contours
overlaid with moment one map obtained from CO(2$-$1, upper panel) and
C18O(2$-$1, bottom panel), respectively. It is observed that CO is perfectly
tracing the globule hosting the compact source detected by the continuum (gray
circle) and corresponding to the center of the bipolar molecular outflow also
evident in the top panel. The width velocity is $\sim$ 5 km s-1, which tells
us that the molecular outflow is not high velocity one. The CO moment zero for
the top panel image was obtained by integrating in the LSR velocity range of
$-$17.88 to $-$27.40 km s-1. The system LSR velocity of the cloud is $\sim$
$-$23 km s-1. The CO is the best tracer of the globule, while the C18O traces
more internal zones of the cloud where the protostar and envelope are
localized. The bottom panel image was obtained by integrating over the LSR
velocity range of $-$21.93 to $-$24.60 km s-1 with a width of velocities
$\sim$ 1 km s-1.

Figure 9: This image is a combination of a HST (optical) $+$ ALMA (radio)
image for the globule HH 1066 located in The Mystic Mountain in Carina. The
optical image (green) is the H$\alpha$ emission from the optical jet and
obscured globule that houses the protostellar compact source traced by ALMA
1.3 mm continuum emission (white contours varying from 50$\%$ to 90$\%$ of the
peak emission, in steps of 10%). The peak of the millimeter continuum emission
is 1.96 mJy Beam-1. We also show the C${18}$O (2$-$1) moment zero (blue and
red colors) for the molecular outflow associated with the protostar. The blue
color corresponds to the blueshifted molecular gas and the red color
corresponds to the redshifted molecular gas. The LSR system velocity of the
globule is about $-$9.18 km s-1. The white arrow indicates the direction where
the star cluster Tr 14 is located.

The gas mass of the globule is 4 $\times$ 10-3 M⊙ and the mass of the outflow
is 2.1 $\times$ 10-3 M⊙ (see Table 3). The globule HH 1006 is affected by the
UV radiation coming from the cluster Tr 16, which has a UV luminosity of (QH)
= 9$\times 10^{50}$ photon s-1, and given the distance at which the source of
the cluster is located ($\sim$16 pc), we obtain a flux F${}_{EUV}=3.09\times
10^{10}$ photons s-1 cm-2. We obtained a mass photoevaporation rate of
5.7$\times 10^{-6}$ M⊙ yr-1 and the photoevaporation timescale of the globule
HH 1006 given the estimated mass of gas (7 $\times$ 10-3 M⊙) is $\sim$1230 yr
(see Table 4).

###  3.5 HH 1010

This source emerges from the tip of a giant dark pillar located at the western
periphery of the Carina nebula, and pointing toward the evolved star $\eta$
Carinae and Tr 16. Smith et al. (2010) detected optical emission within the
pillar, although their detection could not be corroborated. From the optical
images, the presence of a bipolar jet becomes evident, also reported by McLeod
et al. (2016), with its jet axis perpendicular to the pillar axis. This
geometrical configuration is commonly observed in Carina Pillars.

In Figure 7, we show an optical image of the HST in H$\alpha$ (green), and our
results obtained with the ALMA observations for the continuum emission at 1.3
mm (white contours) and the CO (2$-$1) molecular emission (red and blue
colors). The continuum emission reveals a compact source at the center of the
pillar head, and that is exciting the molecular outflow. This outflow extends
along the jet axis at velocities between $-$9 and $-$27 km s-1. This continuum
emission has an integrated flux of 4.12 $\pm$ 0.17 mJy. We were not able to
resolve the source because the angular resolution was not sufficient (see
Table 1).

The dust mass for the continuum source is between 0.08$-$0.21 M⊙, assuming
temperature values between 20 and 50 K. The CO is tracing the outflow and was
obtained by integrating the emission in radial velocities from $-$9.54 to
$-$15.25 km s-1 for the redshifted emission oriented to the south, and from
$-$18.43 to $-$27.32 km s-1 for the blueshifted emission oriented to the north
of the pillar. Red/Blueshifted distribution is consistent with McLeod et al.
(2016) observations.

Figure 10: Images of moment zero (contours) and moment one (colors) are
presented for the molecular emission of C18O (2$-$1) (top panel) and moment
one of N2D+(3$-$2) (bottom panel) of the globule of HH 1066. The C18O moment
zero presents the emission in contours varying from 10% to 90% of the peak
emission, in steps of 15%. The peak of the millimeter line C18O emission is
0.11 Jy Beam-1 km s-1. The gray circles in both figures represent the location
of the compact source (system disk$+$envelope) detected in the continuum at
1.3 mm. The LSR radial-velocity scale bar is shown on the right.

In Figure 8, we show the emission of molecular gas for the CO (2$-$1) and C18O
(2$-$1) transitions. The moment zero (black contours) represents the CO
emission in both panels. The moment one is presented (in colors) for the CO
(top panel) and C18O (bottom panel). For the top panel, the CO moment zero
image was obtained by integrating in the velocity range of $-$9.54 to $-$27.32
km s-1, with the average LSR velocity of the cloud $\sim$ $-$16 km s-1. The
bottom panel image was obtained by integrating over the velocity range of
$-$15.65 to $-$18.65 km s-1 km s-1, with the average LSR velocity of the cloud
$\sim$ $-$17 km s-1. We note the fact of the CO is tracing perfectly the
pillar in all its extension and the accurate shape of the molecular outflow is
still evident even considering all the CO emission. The C18O is again tracing
zones deep inside the cloud, where the protostar is forming and therefore the
density is higher.

The estimated gas mass for the HH 1010 object is 7 $\times$ 10-2 M⊙ and the
mass of the outflow is 1.5 $\times$ 10-3 M⊙ (see Table 3). The globule HH 1010
is affected by the UV radiation coming from the cluster Tr 14, given the
distance at which the source of the cluster is located ($\sim$13 pc), we
obtain a flux of F${}_{EUV}=1.02\times 10^{10}$ photons s-1 cm-2, and the mass
photoevaporation rate 3.1$\times 10^{-5}$ M⊙ yr-1, yielding a photoevaporation
timescale $\sim$2260 yr (see Table 4).

###  3.6 HH 1066

This object was detected to the west of the Carina nebula very close to the Tr
14 star cluster just above the HH 901 and 902 sources, which all together form
the structure known as The Mystic
Mountain141414https://hubblesite.org/contents/media/images/2010/13/2707-Image.html?news=true.
The detected jet is approximately 0.05 pc in extent and is associated with
what appears to be a small, bright bow shock (see Smith et al. 2010) although
without an obvious optical jet counterpart. Through optical observations
(H$\alpha$) they were able to detect a weak point source of emission located
at the tip of the dark cloud and within the axis of the optical jet, which was
also detected with IR observations of Spitzer (YSO detected along the optical
jet, see Povich et al. 2011) without a clear association with the driving
source. Further optical and IR observations Reiter & Smith (2013) made evident
the bipolarity of the collimated jet detected in H$\alpha$ and [Fe II] but
again without being able to evidence the complementary bow shock.

In Figure 9, we show an optical image from the HST (in H$\alpha$, in green)
and our results obtained with ALMA observations for the continuum emission (at
1.3 mm in white contours) and the C18O molecular emission (red and blue
colors). In this case, it was not possible to highlight the outflow with
CO(2$-$1) emission due to contamination of ambient gas, and the structures
near the globule. Although we tried to reproduce the innermost zone (blue and
red colors) of the C18O molecular outflow (in the previous cases where we have
used CO), the emission plotted in Figure 9 only represents the innermost zones
of the molecular cloud, without clearly outlining the outflow. The emission in
this case was integrated over the LSR velocity range of $-$7.51 to $-$8.18 km
s-1 for the redshifted gas and $-$9.84 to $-10.18$ for the blueshifted gas.

From the continuum emission, we detected a compact dust source associated with
the envelope and disk structure, where the protostellar source is embedded
(component A, see Figure 9), and a compact emission source (component B). For
component A, we obtained an integrated flux of 3.86 $\pm$ 0.66 mJy, and a rms
noise of 0.05 mJy (see Table 1). From the synthesized beam size (0′′.26
$\times$ 0′′.18), we obtained a deconvolved size of 0.′′373 $\pm$ 0.′′085
$\times$ 0.′′211 $\pm$ 0.′′092, with a PA of 170${}^{\circ}\pm$ 26∘, which
corresponds to an approximate physical size of 850 $\times$ 490 au. We
estimated the dust mass from the continuum emission and obtained values
between 0.07$-$0.19 M⊙, varying the temperature between 20 and 50 K, these
values are in agreement with the estimated values by Mesa-Delgado et al.
(2016) (they estimated the mass $\sim$ 0.04M⊙), we clearly are recovering some
extended emission. Additionally, we report for the first time the detection
for component B, whose integrated flux of 2.9 mJy and peak flux of 0.8 mJy,
are about an order of magnitude larger than rms value. There was no gas
detection associated with this component.

In Figure 10, we show the moment zero obtained from the C18O (2$-$1)
(contours) combined with moment one image obtained from the C18O (2$-$1)
(upper panel) and N2D+(3$-$2) (bottom panel) emissions, respectively. This is
the only source in this study where we detected N2D+(3$-$2) emission. The
moment zero image of C18O perfectly traces the globule of HH 1066, and it does
not extend beyond the boundary delimited by the optical emission detected in
H$\alpha$ (see Figure 9). The moment one reveals gas kinematics, that for
C18O, evidences a small velocity gradient with ranges between $-$7 to $-$10 km
s-1, with higher velocities toward the outer walls of the globule. In the case
of N2D+ moment one, the velocities vary over a smaller range from $-$8 to $-$9
km s-1, and the structure traced by the gas is located in the innermost
regions of the globule, close to the protostellar source detected by the
continuum emission (gray circle).

###  3.7 Planet Formation

We can examine if the results obtained for the compact disks$+$envelopes
revealed in our 1.3 mm continuum maps for the HH objects are in principle
consistent with the formation of planets. If we consider the lowest value
obtained for the masses of the disks$+$envelopes (0.01 M⊙ for HH 1004
component B) which corresponds to $\sim$ 10 MJup, we can see that is above the
minimum required mass (10 MJup) for a pre-solar nebula to develop a planetary
system (Weidenschilling, 1977). However, we remark that there is probably
contamination of the dusty envelope, so the mass of the disk could be lower.
However, if we consider the maximum mass value obtained (0.77 M⊙ for HH 666),
corresponding to $\sim$ 800 MJup, we see that it is well above the minimum
required, which is the case for many other sources detected with our
observations, so at least in most of the sources this minimum mass condition
is fulfilled.

On the other hand, a second important factor to consider is the average age of
the Carina population which is $\sim$1–4 Myr (Smith & Brooks, 2008),
consistent with the minimum time-scale required to form planets $\sim$1–2 Myr
(see Hubickyj et al. (2005); Najita & Kenyon (2014)). The external UV
irradiance from Tr 14 and Tr 16 could photodisociate the material of the
disks. However, these disks are still very embedded within the globules and
pillars implying that they are not strongly irradiated yet. All these
conditions indicate the possibility that there are young planets formed or in
formation in these detected disks.

##  4 Conclusions

In this work, we present a study of six pillars/globules localized in the star
forming region of Carina. We used Atacama Large Millimeter/submillimeter Array
observations at 1.3 mm continuum, C18O(2$-$1) and 12CO(2$-$1) spectral lines
with high angular resolution and sensitivity. We have studied each source
associated with the Herbig-Haro objects, and their nearby environment, aiming
to identify and analyze various characteristics that are influencing each of
the pillars/globules. The most significant results derived from this study are
as follows:

  1. i.

For the first time, we have successfully identified the millimeter compact
sources associated with the Herbig-Haro objects HH 666, HH 1004, HH 1006, HH
1010, and HH 1066 along with the first detection of its component B. We also
detected the CO bipolar molecular outflows associated with these continuum
sources, extending along the optical jet axis.

  2. ii.

From the observations, we have characterized the objects from the
morphological analysis of the detected structures, revealing sizes of the
pillars/globules and of the detected continuum structures, for which we have
concluded that, given the sizes found (80$-$2600 au), they correspond to
structures associated with the dusty disks ($\sim$100 au) and the envelope of
the forming star, for which we have also calculated the dust masses, finding
values between 0.01$-$0.7 M⊙. Between these values, planetary formation would
be possible.

  3. iii.

We have also estimated the gas mass for the detected molecular outflows from
the CO emission, giving values of 1.4$\times$10-3 $-$ 2.1$\times$ 10-3 M⊙, and
the same for the pillars/globules, which obtained values of 7$\times$10-3 $-$
7$\times$10-2 M⊙. These estimations only include the HH 900, HH 1006, HH 1010,
and HH 1066 sources since only for these we obtained CO detection for the
pillars/globules.

  4. iv.

We present the gas kinematics for the 12CO and C18O molecular lines,
estimations for the mass photoevaporation rates for the HH 900, HH 1006, HH
1010, and HH 1066 sources, with a range from 5.7 $\times$ 10-6 to 3.1 $\times$
10-5 M⊙ yr-1, indicating that these pillars/globules will be photoevaporated
on time scales of the order of 150$-$2200 yr.

This paper makes use of the following ALMA data: ADS/JAO.ALMA#2017.1.00912.S
ALMA is a partnership of ESO (representing its member states), NSF (USA), and
NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI
(Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA
Observatory is operated by ESO, AUI/NRAO, and NAOJ. The National Radio
Astronomy Observatory is a facility of the National Science Foundation
operated under cooperative agreement by Associated Universities, Inc. G.C.R.
is grateful to CONACyT, México, and DGAPA, UNAM for the financial support.
L.A.Z. acknowledges financial support from CONACyT-280775 and UNAM-PAPIIT
IN110618, and IN112323 grants, México. P.R.R-O. acknowledges support from the
UNAM-PAPIIT IN110722 grant, CONACyT, México, and DGAPA, UNAM. The HST data
presented in this paper were obtained from the Mikulski Archive for Space
Telescopes (MAST) at the Space Telescope Science Institute. The specific
observations analyzed can be accessed via https://doi.org/10.17909/p1je-9b56
(catalog 10.17909/p1je-9b56).

## References

  * Andrews (2020) Andrews, S. M. 2020, ARA&A, 58, 483, doi: 10.1146/annurev-astro-031220-010302
  * CASA Team et al. (2022) CASA Team, Bean, B., Bhatnagar, S., et al. 2022, PASP, 134, 114501, doi: 10.1088/1538-3873/ac9642
  * Cortes-Rangel et al. (2020) Cortes-Rangel, G., Zapata, L. A., Toalá, J. A., et al. 2020, AJ, 159, 62, doi: 10.3847/1538-3881/ab6295
  * Henney & O’Dell (1999) Henney, W. J., & O’Dell, C. R. 1999, AJ, 118, 2350, doi: 10.1086/301087
  * Hubickyj et al. (2005) Hubickyj, O., Bodenheimer, P., & Lissauer, J. J. 2005, Icarus, 179, 415, doi: 10.1016/j.icarus.2005.06.021
  * Klaassen et al. (2019) Klaassen, P. D., Reiter, M. R., McLeod, A. F., et al. 2019, Monthly Notices of the Royal Astronomical Society, 491, 178, doi: 10.1093/mnras/stz3012
  * McLeod et al. (2016) McLeod, A. F., Gritschneder, M., Dale, J. E., et al. 2016, MNRAS, 462, 3537, doi: 10.1093/mnras/stw1864
  * Mesa-Delgado et al. (2016) Mesa-Delgado, A., Zapata, L., Henney, W. J., Puzia, T. H., & Tsamis, Y. G. 2016, ApJ, 825, L16, doi: 10.3847/2041-8205/825/1/L16
  * Najita & Kenyon (2014) Najita, J. R., & Kenyon, S. J. 2014, MNRAS, 445, 3315, doi: 10.1093/mnras/stu1994
  * Noriega-Crespo et al. (2020) Noriega-Crespo, A., Raga, A. C., Lora, V., & Rodríguez-Ramírez, J. C. 2020, Rev. Mexicana Astron. Astrofis., 56, 29, doi: 10.22201/ia.01851101p.2020.56.01.05
  * O’dell et al. (1993) O’dell, C. R., Wen, Z., & Hu, X. 1993, ApJ, 410, 696, doi: 10.1086/172786
  * Ossenkopf & Henning (1994) Ossenkopf, V., & Henning, T. 1994, A&A, 291, 943
  * Povich et al. (2011) Povich, M. S., Smith, N., Majewski, S. R., et al. 2011, ApJS, 194, 14, doi: 10.1088/0067-0049/194/1/14
  * Reipurth & Bally (2001) Reipurth, B., & Bally, J. 2001, ARA&A, 39, 403, doi: 10.1146/annurev.astro.39.1.403
  * Reipurth et al. (2019) Reipurth, B., Davis, C. J., Bally, J., et al. 2019, AJ, 158, 107, doi: 10.3847/1538-3881/ab2d25
  * Reiter et al. (2020a) Reiter, M., Guzmán, A. E., Haworth, T. J., et al. 2020a, MNRAS, 496, 394, doi: 10.1093/mnras/staa1504
  * Reiter et al. (2020b) Reiter, M., Haworth, T. J., Guzmán, A. E., et al. 2020b, MNRAS, 497, 3351, doi: 10.1093/mnras/staa2156
  * Reiter et al. (2019) Reiter, M., McLeod, A. F., Klaassen, P. D., et al. 2019, MNRAS, 490, 2056, doi: 10.1093/mnras/stz2752
  * Reiter & Smith (2013) Reiter, M., & Smith, N. 2013, MNRAS, 433, 2226, doi: 10.1093/mnras/stt889
  * Reiter et al. (2016) Reiter, M., Smith, N., & Bally, J. 2016, MNRAS, 463, 4344, doi: 10.1093/mnras/stw2296
  * Reiter et al. (2015a) Reiter, M., Smith, N., Kiminki, M. M., & Bally, J. 2015a, MNRAS, 450, 564, doi: 10.1093/mnras/stv634
  * Reiter et al. (2015b) Reiter, M., Smith, N., Kiminki, M. M., Bally, J., & Anderson, J. 2015b, MNRAS, 448, 3429, doi: 10.1093/mnras/stv177
  * Sahai et al. (2012) Sahai, R., Güsten, R., & Morris, M. R. 2012, ApJ, 761, L21, doi: 10.1088/2041-8205/761/2/L21
  * Scoville et al. (1986) Scoville, N. Z., Sargent, A. I., Sanders, D. B., et al. 1986, ApJ, 303, 416, doi: 10.1086/164086
  * Shinn et al. (2013) Shinn, J.-H., Pyo, T.-S., Lee, J.-J., et al. 2013, ApJ, 777, 45, doi: 10.1088/0004-637X/777/1/45
  * Smith et al. (2004) Smith, N., Bally, J., & Brooks, K. J. 2004, AJ, 127, 2793, doi: 10.1086/383291
  * Smith et al. (2010) Smith, N., Bally, J., & Walborn, N. R. 2010, MNRAS, 405, 1153, doi: 10.1111/j.1365-2966.2010.16520.x
  * Smith & Brooks (2008) Smith, N., & Brooks, K. J. 2008, in Handbook of Star Forming Regions, Volume II, ed. B. Reipurth, Vol. 5, 138
  * Weidenschilling (1977) Weidenschilling, S. J. 1977, MNRAS, 180, 57, doi: 10.1093/mnras/180.2.57