arXiv subjects

Aina Palau

Publications and source records attributed to Aina Palau.

At least 73 records · Page 4Linked to original sources

arXiv2017

Molecular outflows: Explosive versus protostellar

With the recent recognition of a second, distinctive class of molecular outflows, namely the explosive ones not directly connected to the accretion-ejection process in the star formation, a juxtaposition of the morphological and kinematic properties of both classes is warranted. By applying the same method used in Zapata et al. (2009), and using $^{12}$CO(J=2-1) archival data from the Submillimeter Array (SMA), we contrast two well known explosive objects, Orion KL and DR21, to HH211 and DG Tau B, two flows representative of classical low-mass protostellar outflows. At the moment there are only two well established cases of explosive outflows, but with the full availability of ALMA we expect that more examples will be found in the near future. Main results are the largely different spatial distributions of the explosive flows, consisting of numerous narrow straight filament-like ejections with different orientations and in almost an isotropic configuration, the red with respect to the blueshifted components of the flows (maximally separated in protostellar, largely overlapping in explosive outflows), the very well-defined Hubble flow-like increase of velocity with distance from the origin in the explosive filaments versus the mostly non-organized CO velocity field in protostellar objects, and huge inequalities in mass, momentum and energy of the two classes, at least for the case of low-mass flows. Finally, all the molecular filaments in the explosive outflows point back to approximately a central position i.e. the place where its "exciting source" was located, contrary to the bulk of the molecular material within the protostellar outflows.

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arXiv2017

Complex Organic Molecules tracing shocks along the outflow cavity in the high-mass protostar IRAS20126+4104

We report on subarcsecond observations of complex organic molecules (COMs) in the high-mass protostar IRAS20126+4104 with the Plateau de Bure Interferometer in its most extended configurations. In addition to the simple molecules SO, HNCO and H2-13CO, we detect emission from CH3CN, CH3OH, HCOOH, HCOOCH3, CH3OCH3, CH3CH2CN, CH3COCH3, NH2CN, and (CH2OH)2. SO and HNCO present a X-shaped morphology consistent with tracing the outflow cavity walls. Most of the COMs have their peak emission at the putative position of the protostar, but also show an extension towards the south(east), coinciding with an H2 knot from the jet at about 800-1000 au from the protostar. This is especially clear in the case of H2-13CO and CH3OCH3. We fitted the spectra at representative positions for the disc and the outflow, and found that the abundances of most COMs are comparable at both positions, suggesting that COMs are enhanced in shocks as a result of the passage of the outflow. By coupling a parametric shock model to a large gas-grain chemical network including COMs, we find that the observed COMs should survive in the gas phase for about 2000 yr, comparable to the shock lifetime estimated from the water masers at the outflow position. Overall, our data indicate that COMs in IRAS20126+4104 may arise not only from the disc, but also from dense and hot regions associated with the outflow.

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arXiv2016

Dense core properties in the Infrared Dark cloud G14.225-0.506 revealed by ALMA

We have performed a dense core survey toward the Infrared Dark Cloud G14.225-0.506 at 3 mm continuum emission with the Atacama Large Millimeter/Submillimeter Array (ALMA). This survey covers the two hub-filament systems with an angular resolution of $\sim3$\arcsec ($\sim0.03$ pc). We identified 48 dense cores. Twenty out of the 48 cores are protostellar due to their association with young stellar objects (YSOs) and/or X-ray point-sources, while the other 28 cores are likely prestellar and unrelated with known IR or X-ray emission. Using APEX 870 $μ$m continuum emission, we also identified the 18 clumps hosting these cores. Through virial analysis using the ALMA N$_2$H$^+$ and VLA/Effelsberg NH$_3$ molecular line data, we found a decreasing trend in the virial parameter with decreasing scales from filaments to clumps, and then to cores. The virial parameters of $0.1-1.3$ in cores, indicate that cores are likely undergoing dynamical collapse. The cumulative Core Mass Function (CMF) for the prestellar cores candidates has a power law index of $α=1.6$, with masses ranging from 1.5 to 22 $M_\odot$. We find no massive prestellar or protostellar cores. Previous studies suggest that massive O-tpye stars have not been produced yet in this region. Therefore, high-mass stars should be formed in the prestellar cores by accreting a significant amount of gas from the surrounding medium. Another possibility is that low-mass YSOs become massive by accreting from their parent cores that are fed by filaments. These two possibilities might be consistent with the scenario of global hierarchical collapse.

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arXiv2016

A correlation between chemistry, polarization and dust properties in the Pipe Nebula starless core FeSt 1-457

Pre-stellar cores within molecular clouds provide the very initial conditions in which stars are formed. We use the IRAM 30m telescope and the PdBI to study the chemical and physical properties of the starless core FeSt 1-457 (Core 109), in the Pipe nebula. We fit the hyperfine structure of the N2H+(1-0) IRAM 30m data. This allow us to measure with high precision the velocity field, line widths and opacity and derive the excitation temperature and column density in the core. We use a modified Bonnor-Ebert sphere model adding a temperature gradient towards the center to fit the 1.2 mm continuum emission and visual extinction maps. Using this model, we estimate the abundances of the N2H+ and the rest of molecular lines detected in the 30 GHz wide line survey performed at 3 mm with IRAM 30m using ARTIST software. The core presents a rich chemistry with emission from early (C3H2, HCN, CS) and late-time molecules (e.g., N2H+), with a clear chemical spatial differentiation for nitrogen, oxygen and sulphurated molecules. For most of the molecules detected (HCN, HCO+, CH3OH, CS, SO, 13CO and C18O), abundances are best fitted with three values, presenting a clear decrease of abundance of at least 1 or 2 orders of magnitude towards the center of the core. The Bonnor-Ebert analysis indicates the core is gravitationally unstable and the magnetic field is not strong enough to avoid the collapse. Depletion of molecules onto the dust grains occurs at the interior of the core, where dust grain growth and dust depolarization also occurs. This suggests that these properties may be related. On the other hand, some molecules exhibit asymmetries in their integrated emission maps, which appear to be correlated with a previously reported submillimetre polarization asymmetry. These asymmetries could be due to a stronger interstellar radiation field in the western side of the core.

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arXiv2016

3.3 cm JVLA observations of transitional disks: searching for centimeter pebbles

We present sensitive (rms-noises $\sim$ 4 -- 25 $μ$Jy) and high angular resolution ($\sim$1--2$"$) 8.9 GHz (3.3 cm) Karl G. Jansky Very Large Array (JVLA) radio continuum observations of 10 presumed transitional disks associated with young low-mass stars. We report the detection of radio continuum emission in 5 out of the 10 objects (RXJ1615, UX Tau A, LkCa15, RXJ1633, and SR24s). In the case of LkCa15, the centimeter emission is extended, and has a similar morphology to that of the transitional disk observed at mm wavelengths with an inner depression. For these five detections, we construct the Spectral Energy Distributions (SEDs) from the centimeter to submillimeter wavelengths, and find that they can be well fitted with a single (RXJ 1633 and UX Tau A) or a two component power-law (LkCa 15, RXJ 1615, and SR24s). For the cases where a single power-law fits well the data, the centimeter emission is likely produced by optically thin dust with large grains i.e. centimeter-size pebbles) present in the transitional disks. For the cases where a double power-law fits the data, the centimeter emission might be produced by the combination of photoevaporation and/or a free-free jet. We conclude that RXJ1633 and UX Tau A are excellent examples of transitional disks where the structure of the emission from centimeter/millimeter pebbles can be studied. In the other cases, some other physical emitting mechanisms are also important in the centimeter regime.

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arXiv2016

Phosphorus-bearing molecules in massive dense cores

Phosphorus is a crucial element for the development of life, but so far P-bearing molecules have been detected only in a few astrophysical objects, hence its interstellar chemistry is almost totally unknown. Here we show new detections of phosphorus nitride in a sample of dense cores in different evolutionary stages of the intermediate- and high-mass star formation process: starless, with protostellar objects, and with ultracompact HII regions. All detected PN line widths are smaller than ~5 km/s , and they arise from regions associated with kinetic temperatures smaller than 100 K. Because the few previous detections reported in the literature are associated with warmer and more turbulent sources, the results of this work show that PN can arise from relatively quiescent and cold gas. This information is challenging for theoretical models that invoke either high desorption temperatures or grain sputtering from shocks to release phosphorus into the gas phase. Derived column densities are of the order of 10^{11-12} cm^{-2}, marginally lower than the values derived in the few high-mass star forming regions detected so far. New constraints on the column density upper limit of phosphorus monoxide, the fundamental unit of biologically relevant molecules, are also given.

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arXiv2015

A submillimeter search for pre- and proto-brown dwarfs in Chamaeleon II

Context. Chamaeleon II molecular cloud is an active star forming region that offers an excellent opportunity for studying the formation of brown dwarfs in the southern hemisphere. Aims. Our aims are to identify a population of pre- and proto- brown dwarfs (5 sigma mass limit threshold of ~0.015 Msun) and provide information on the formation mechanisms of substellar objects. Methods. We performed high sensitivity observations at 870 microns using the LABOCA bolometer at the APEX telescope towards an active star forming region in Chamaeleon II. The data are complemented with an extensive multiwavelength catalogue of sources from the optical to the far-infrared to study the nature of the LABOCA detections. Results. We detect fifteen cores at 870 microns, and eleven of them show masses in the substellar regime. The most intense objects in the surveyed field correspond to the submillimeter counterparts of the well known young stellar objects DK Cha and IRAS 12500-7658. We identify a possible proto-brown dwarf candidate (ChaII-APEX-L) with IRAC emission at 3.6 and 4.5 microns. Conclusions. Our analysis indicates that most of the spatially resolved cores are transient, and that the point-like starless cores in the sub-stellar regime (with masses between 0.016 Msun and 0.066 Msun) could be pre-brown dwarfs cores gravitationally unstable if they have radii smaller than 220 AU to 907 AU (1.2" to 5" at 178 pc) respectively for different masses. ALMA observations will be the key to reveal the energetic state of these pre-brown dwarfs candidates.

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arXiv2015

Ongoing star formation in the proto-cluster IRAS 22134+5834

IRAS 22134+5834 was observed in the centimeter with (E)VLA, 3~mm with CARMA, 2~mm with PdBI, and 1.3~mm with SMA, to study the continuum emission as well as the molecular lines, that trace different physical conditions of the gas to study the influence of massive YSOs on nearby starless cores, and the possible implications in the clustered star formation process. The multi-wavelength centimeter continuum observations revealed two radio sources within the cluster, VLA1 and VLA2. VLA1 is considered to be an optically thin UCHII region with a size of 0.01~pc and sits at the edge of the near-infrared (NIR) cluster. The flux of ionizing photons of the VLA1 corresponds to a B1 ZAMS star. VLA2 is associated with an infrared point source and has a negative spectral index. We resolved six millimeter continuum cores at 2~mm, MM2 is associated with the UCHII region VLA1, and other dense cores are distributed around the UCH{\sc ii} region. Two high-mass starless clumps (HMSC), HMSC-E (east) and HMSC-W (west), are detected around the NIR cluster with N$_2$H$^+$(1--0) and NH$_3$ emission, and show different physical and chemical properties. Two N$_2$D$^+$ cores are detected on an NH$_3$ filament close to the UCHII region, with a projected separation of $\sim$8000~AU at the assumed distance of 2.6~kpc. The kinematic properties of the molecular line emission confirm the expansion of the UCHII region and that the molecular cloud around the near infrared (NIR) cluster is also expanding. Our multi-wavelength study has revealed different generations of star formation in IRAS 22134+5834. The formed intermediate- to massive stars show strong impact on nearby starless clumps. We propose that while the stellar wind from the UCHII region and the NIR cluster drives the large scale bubble, the starless clumps and HMPOs formed at the edge of the cluster.

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arXiv2015

Gravity or turbulence? -III. Evidence of pure thermal Jeans fragmentation at ~0.1 pc scale

We combine previously published interferometric and single-dish data of relatively nearby massive dense cores that are actively forming stars to test whether their `fragmentation level' is controlled by turbulent or thermal support. We find no clear correlation between the fragmentation level and velocity dispersion, nor between the observed number of fragments and the number of fragments expected when the gravitationally unstable mass is calculated including various prescriptions for `turbulent support'. On the other hand, the best correlation is found for the case of pure thermal Jeans fragmentation, for which we infer a core formation efficiency around 13 per cent, consistent with previous works. We conclude that the dominant factor determining the fragmentation level of star-forming massive dense cores at 0.1 pc scale seems to be thermal Jeans fragmentation.

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arXiv2015

Radio monitoring of the periodically variable IR source LRLL 54361: No direct correlation between the radio and IR emissions

LRLL 54361 is an infrared source located in the star forming region IC 348 SW. Remarkably, its infrared luminosity increases by a factor of 10 during roughly one week every 25.34 days. To understand the origin of these remarkable periodic variations, we obtained sensitive 3.3 cm JVLA radio continuum observations of LRLL 54361 and its surroundings in six different epochs: three of them during the IR-on state and three during the IR-off state. The radio source associated with LRLL 54361 remained steady and did not show a correlation with the IR variations. We suggest that the IR is tracing the results of fast (with a timescale of days) pulsed accretion from an unseen binary companion, while the radio traces an ionized outflow with an extent of $\sim$100 AU that smooths out the variability over a period of order a year. The average flux density measured in these 2014 observations, 27$\pm$5 $μ$Jy, is about a factor of two less than that measured about 1.5 years before, $53\pm$11 $μ$Jy, suggesting that variability in the radio is present, but over larger timescales than in the IR. We discuss other sources in the field, in particular two infrared/X-ray stars that show rapidly varying gyrosynchrotron emission.

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arXiv2015

Origin and kinematics of the eruptive flow from XZ Tau revealed by ALMA

We present high angular resolution ($\sim$0.94$"$) $^{12}$CO(1-0) Atacama Large Millimeter/Submillimeter Array (ALMA) observations obtained during the 2014 long baseline campaign from the eruptive bipolar flow from the multiple XZ Tau stellar system discovered by the Hubble Space Telescope (HST). These observations reveal, for the first time, the kinematics of the molecular flow. The kinematics of the different ejections close to XZ Tau reveal a rotating and expanding structure with a southeast-northwest velocity gradient. The youngest eruptive bubbles unveiled in the optical HST images are inside of this molecular expanding structure. Additionally, we report a very compact and collimated bipolar outflow emanating from XZ Tau A, which indicates that the eruptive outflow is indeed originating from this object. The mass (3 $\times$ 10$^{-7}$ $M_\odot$) and energetics (E$_{kin}$ $=$ 3 $\times$ 10$^{37}$ ergs) for the collimated outflow are comparable with those found in molecular outflows associated with young brown dwarfs.

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arXiv2015

Pre- and Post-burst Radio Observations of the Class 0 Protostar HOPS 383 in Orion

There is increasing evidence that episodic accretion is a common phenomenon in Young Stellar Objects (YSOs). Recently, the source HOPS 383 in Orion was reported to have a $\times 35$ mid-infrared -- and bolometric -- luminosity increase between 2004 and 2008, constituting the first clear example of a class 0 YSO (a protostar) with a large accretion burst. The usual assumption that in YSOs accretion and ejection follow each other in time needs to be tested. Radio jets at centimeter wavelengths are often the only way of tracing the jets from embedded protostars. We searched the Very Large Array archive for the available observations of the radio counterpart of HOPS 383. The data show that the radio flux of HOPS 383 varies only mildly from January 1998 to December 2014, staying at the level of $\sim 200$ to 300 $μ$Jy in the X band ($\sim 9$ GHz), with a typical uncertainty of 10 to 20 $μ$Jy in each measurement. We interpret the absence of a radio burst as suggesting that accretion and ejection enhancements do not follow each other in time, at least not within timescales shorter than a few years. Time monitoring of more objects and specific predictions from simulations are needed to clarify the details of the connection betwen accretion and jets/winds in YSOs.

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arXiv2014

ALMA reveals a candidate hot and compact disk around the O-type protostar IRAS 16547$-$4247

We present high angular resolution ($\sim$ 0.3$"$) submillimeter continuum (0.85 mm) and line observations of the O-type protostar IRAS 16547$-$4247 carried out with the Atacama Large Millimeter/Submillimeter Array (ALMA). In the 0.85 mm continuum band, the observations revealed two compact sources (with a separation of 2$"$), one of them associated with IRAS 16547$-$4247, and the other one to the west. Both sources are well resolved angularly, revealing a clumpy structure. On the other hand, the line observations revealed a rich variety of molecular species related to both continuum sources. In particular, we found a large number of S-bearing molecules, such as the rare molecule methyl mercaptan (CH$_3$SH). At scales larger than 10,000 AU, molecules (e.g., SO$_2$ or OCS) mostly with low excitation temperatures in the upper states (E$_k$ $\lesssim$ 300 K) are present in both millimeter continuum sources, and show a southeast-northwest velocity gradient of 7 km s$^{-1}$ over 3$"$ (165 km s$^{-1}$ pc$^{-1}$). We suggest that this gradient probably is produced by the thermal (free-free) jet emerging from this object with a similar orientation at the base. At much smaller scales (about 1000 AU), molecules with high excitation temperatures (E$_k$ $\gtrsim$ 500 K) are tracing a rotating structure elongated perpendicular to the orientation of the thermal jet, which we interpret as a candidate disk surrounding IRAS 16547$-$4247. The dynamical mass corresponding to the velocity gradient of the candidate to disk is about 20 M$_\odot$, which is consistent with the bolometric luminosity of IRAS 16547$-$4247.

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arXiv2014

Deuteration and evolution in the massive star formation process: the role of surface chemistry

An ever growing number of observational and theoretical evidence suggests that the deuterated fraction (column density ratio between a species containing D and its hydrogenated counterpart, Dfrac) is an evolutionary indicator both in the low- and the high-mass star formation process. However, the role of surface chemistry in these studies has not been quantified from an observational point of view. In order to compare how the deuterated fractions of species formed only in the gas and partially or uniquely on grain surfaces evolve with time, we observed rotational transitions of CH3OH, 13CH3OH, CH2DOH, CH3OD at 3 and 1.3~mm, and of NH2D at 3~mm with the IRAM-30m telescope, and the inversion transitions (1,1) and (2,2) of NH3 with the GBT, towards most of the cores already observed by Fontani et al.~(2011, 2014) in N2H+, N2D+, HNC, DNC. NH2D is detected in all but two cores, regardless of the evolutionary stage. Dfrac(NH3) is on average above 0.1, and does not change significantly from the earliest to the most evolved phases, although the highest average value is found in the protostellar phase (~0.3). Few lines of CH2DOH and CH3OD are clearly detected, and only towards protostellar cores or externally heated starless cores. This work clearly confirms an expected different evolutionary trend of the species formed exclusively in the gas (N2D+ and N2H+) and those formed partially (NH2D and NH3) or totally (CH2DOH and CH3OH) on grain mantles. The study also reinforces the idea that Dfrac(N2H+) is the best tracer of massive starless cores, while high values of Dfrac(CH3OH) seem rather good tracers of the early protostellar phases, at which the evaporation/sputtering of the grain mantles is most efficient.

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arXiv2014

IC348-SMM2E: a Class 0 proto-brown dwarf candidate forming as a scaled-down version of low-mass stars

We report on Submillimeter Array observations of the 870 micron continuum and CO(3-2), 13CO(2-1) and C18O(2-1) line emission of a faint object, SMM2E, near the driving source of the HH797 outflow in the IC348 cluster. The continuum emission shows an unresolved source for which we estimate a mass of gas and dust of 30 Mjup, and the CO(3-2) line reveals a compact bipolar outflow centred on SMM2E, and barely seen also in 13CO(2-1). In addition, C18O(2-1) emission reveals hints of a possible rotating envelope/disk perpendicular to the outflow, for which we infer a dynamical mass of ~16 Mjup. In order to further constrain the accreted mass of the object, we gathered data from Spitzer, Herschel, and new and archive submillimetre observations, and built the Spectral Energy Distribution (SED). The SED can be fitted with one single modified black-body from 70 micron down to 2.1 cm, using a dust temperature of ~24 K, a dust emissivity index of 0.8, and an envelope mass of ~35 Mjup. The bolometric luminosity is 0.10 Lsun, and the bolometric temperature is 35 K. Thus, SMM2E is comparable to the known Class 0 objects in the stellar domain. An estimate of the final mass indicates that SMM2E will most likely remain substellar, and the SMM2E outflow force matches the trend with luminosity known for young stellar objects. Thus, SMM2E constitutes an excellent example of a Class 0 proto-brown dwarf candidate which forms as a scaled-down version of low-mass stars. Finally, SMM2E seems to be part of a wide (~2400 AU) multiple system of Class 0 sources.

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arXiv2014

A CO survey in planet-forming disks: characterizing the gas content in the epoch of planet formation

We carried out a 12CO(3-2) survey of 52 southern stars with a wide range of IR excesses (LIR/L*) using the single dish telescopes APEX and ASTE. The main aims were (1) to characterize the evolution of molecular gas in circumstellar disks using LIR/L* values as a proxy of disk dust evolution, and (2) to identify new gas-rich disk systems suitable for detailed study with ALMA. About 60% of the sample (31 systems) have LIR/L* > 0.01 typical of T-Tauri or Herbig AeBe stars, and the rest (21 systems) have LIR/L* < 0.01 typical of debris disks. We detect CO(3-2) emission from 20 systems, and 18 (90%) of these have LIR/L* > 0.01. However, the spectra of only four of the newly detected systems appear free of contamination from background or foreground emission from molecular clouds. These include the early-type stars HD 104237 (A4/5V, 116 pc) and HD 98922 (A2 III, 507 pc, as determined in this work), where our observations reveal the presence of CO-rich circumstellar disks for the first time. Of the other detected sources, many could harbor gaseous circumstellar disks, but our data are inconclusive. For these two newly discovered gas-rich disks, we present radiative transfer models that simultaneously reproduce their spectral energy distributions and the 12CO(3-2) line profiles. For both of these systems, the data are fit well by geometrically flat disks, placing them in the small class of non-flaring disks with significant molecular gas reservoirs.

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arXiv2014

The hot core towards the intermediate mass protostar NGC7129 FIRS 2: Chemical similarities with Orion KL

NGC 7129 FIRS 2 (hereafter FIRS 2) is an intermediate-mass (2 to 8 Msun) protostar located at a distance of 1250 pc. High spatial resolution observations are required to resolve the hot core at its center. We present a molecular survey from 218200 MHz to 221800 MHz carried out with the IRAM Plateau de Bure Interferometer. These observations were complemented with a long integration single-dish spectrum taken with the IRAM 30m telescope. We used a Local Thermodynamic Equilibrium (LTE) single temperature code to model the whole dataset. The interferometric spectrum is crowded with a total of ~300 lines from which a few dozens remain unidentified yet. The spectrum has been modeled with a total of 20 species and their isomers, isotopologues and deuterated compounds. Complex molecules like methyl formate (CH3OCHO), ethanol (CH3CH2OH), glycolaldehyde (CH2OHCHO), acetone (CH3COCH3), dimethyl ether (CH3OCH3), ethyl cyanide (CH3CH2CN) and the aGg' conformer of ethylene glycol (aGg'-(CH2OH)_2) are among the detected species. The detection of vibrationally excited lines of CH3CN, CH3OCHO, CH3OH, OCS, HC3N and CH3CHO proves the existence of gas and dust at high temperatures. In fact, the gas kinetic temperature estimated from the vibrational lines of CH3CN, ~405 K, is similar to that measured in massive hot cores. Our data allow an extensive comparison of the chemistry in FIRS~2 and the Orion hot core. We find a quite similar chemistry in FIRS 2 and Orion. Most of the studied fractional molecular abundances agree within a factor of 5. Larger differences are only found for the deuterated compounds D2CO and CH2DOH and a few molecules (CH3CH2CN, SO2, HNCO and CH3CHO). Since the physical conditions are similar in both hot cores, only different initial conditions (warmer pre-collapse phase in the case of Orion) and/or different crossing time of the gas in the hot core can explain this behavior.

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arXiv2014

A spider-like outflow in Barnard 5 - IRS 1: The transition from a collimated jet to a wide-angle outflow?

We present line and continuum observations made with the Submillimeter Array (SMA) of the young stellar object Barnard 5 - IRS1 located in the Perseus molecular cloud. Our $^{12}$CO(2-1) line observations resolve the high-velocity bipolar northeast-southwest outflow associated with this source. We find that the outflowing gas shows different structures at three different velocity regimes, in both lobes, resulting in a spider-like morphology. In addition to the low-velocity, cone-like (wide-angle) lobes that have previously been observed, we report the presence of intermediate-velocity parabolic shells emerging very close to the Class I protostar, as well as high velocity molecular bullets that appear to be associated to the optical/IR jet emanating from this source. These compact high-velocity features reach radial velocities of about 50 km s$^{-1}$ away from the cloud velocity. We interpret the peculiar spider-like morphology is a result of the molecular material being entrained by a wind with both a collimated jet-like component and a wide-angle component. We suggest the outflow is in a transitional evolutionary phase between a mostly jet-driven flow and an outflow in which the entrainment is dominated by the wide-angle wind component. We also detect 1300 $μ$m continuum emission at the position of the protostar, which likely arises from the dusty envelope and disk surrounding the protostar. Finally, we report the detection of $^{13}$CO(2-1) and SO(6$_5$-5$_4$) emission arising from the outflow and the location of the young stellar object.

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