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Naomi Hirano

Publications and source records attributed to Naomi Hirano.

At least 19 recordsLinked to original sources

ALMA 2D super-resolution imaging survey of Ophiuchus Class I/flat spectrum/II disks. II. Statistical analysis of stellar and disk properties

We present a statistical study of stellar and dust disk properties for young stellar objects in the Ophiuchus star-forming region. Building on our previous paper (Shoshi et al. 2025b), which applied two-dimensional super-resolution imaging with PRIISM to ALMA archival Band 6 continuum data and spatially resolved 78 disks, we analyze a sample of 67 systems with robust dust-radius measurements. We combine stellar parameters from the literature, including bolometric temperature $T_{\rm bol}$, stellar mass $M_\ast$, and mass accretion rate $\dot{M}_{\rm acc}$, with disk parameters derived from the super-resolution images, including inclination $i_{\rm disk}$, millimeter luminosity $L_{\rm mm}$, and dust radius $R_{95\%}$. We quantify pairwise correlations and compare their behavior across evolutionary stages (Class I/FS and Class II) and between disks with and without detectable substructures. We identify substructure dependencies in $L_{\rm mm}$ and $R_{95\%}$, indicating that substructures tend to be found preferentially in relatively massive and extended disks. Moreover, we find a tight size-luminosity relation between $R_{95\%}$ and $L_{\rm mm}$. In particular, only Class II disks with substructures exhibit a steeper scaling, $R_{95\%}\propto L_{\rm mm}^{0.8}$, while the other subsamples are broadly consistent with $R_{95\%}\propto L_{\rm mm}^{0.4\text{-}0.5}$. This behavior is qualitatively consistent with disk evolution models in which disks with planet-induced pressure bumps follow a steeper size-luminosity relation than smooth disks. Overall, our results suggest that disk substructures play an important role in shaping the evolution of dust and global disk properties, while providing empirical constraints on accretion, dust trapping, and possible gravitational instability in young disks.

astro-ph.EP

Observations of DNC and DCO$^+$ toward the $\int$-shaped Filament and Starless Cores in the Orion Molecular Clouds

Although the deuterium fraction is known to be a powerful evolutionary tracer, its variation within individual molecular cloud cores is still poorly understood. The northern $\int$-shaped filament and 20 individual starless cores in the Orion A and B clouds were mapped in the deuterated molecules of DNC and DCO$^+$ with the Receiver 7BEE installed on the Nobeyama 45~m radio telescope. In a ~ 5' X 30' map of the northern $\int$-shaped filament in the Orion A cloud, the DNC emission is detected over the filament, whereas the DCO$^+$ emission is localized toward OMC-3, the northernmost region of the filament. The difference in distribution between DNC and DCO$^+$ can be attributed to that between N- and C-bearing molecules as previously suggested by Tatematsu et al. High DNC/HN$^{13}$C column density ratios were observed in OMC-2 and OMC-3, and low ratios in OMC-1. It seems that OMC-2 and OMC-3 still contain molecular gas close to the onset of star formation. In 3' X 3' maps of the individual starless cores in Orion, the column density ratios of DNC/HN$^{13}$C and DCO$^+$/H$^{13}$CO$^+$ are found to be rather constant locally within each core, although the core-to-core variation is not small. Similar timescales of deuterization, depletion, and dynamical evolution might explain the locally constant ratio.

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Q/W-band Observations toward Starless Cores in Orion (QWOSCO) I. Overview, Isotopologues, Isomers, and Complex Organics

Molecular inventories in starless cores are powerful tools for probing the physical and chemical structures at the earliest stages of star formation. Wide-band spectral scans are invaluable for obtaining a comprehensive view of the chemical composition. In this paper, we present the first results from the project Q/W-band Observations toward Starless Cores in Orion (QWOSCO), which uses the Yebes 40-m telescope to survey 23 starless cores in the Orion cloud at the Q (31.0--50.5 GHz) and W (71.1--91.4 GHz) bands with a total bandwidth of 40 GHz. We detect approximately 40 molecular species and derive their column densities, with each species exhibiting a characteristic spread of roughly one order of magnitude. The derived isomer and isotopologue column density ratios, including A/E, ortho/para, cyclic/linear, HNC/HCN, 12C/13C, 14N/15N, 16O/18O, 32S/34S, and D/H, are consistent with expectations for starless environments. Our results together with the literature suggest that the complex organic molecules (COMs) CH3OH and CH3CHO are both likely ubiquitous in starless cores. The column density ratio of CH3CHO with respect to CH3OH in starless cores are comparable or lower by a factor of around 25 than those in hot corinos at the protostellar stages if the CH3OH column density is directly derived or rescaled from that of 13CH3OH, respectively. Accordingly, we discuss the possible roles of methanol opacity and chemical mechanisms across the starless and protostellar stages.

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HOPS-288: A Laboratory for Complex Organics in Proto-multiple Systems

Complex organic molecules (COMs) in young stellar objects (YSOs) have attracted significant attention in recent years due to their potential connection to pre-biotic chemistry and their utility as tracers of warm or shocked gas components. Proto-binary and multiple systems with close separations are particularly valuable targets for investigating chemical inheritance and reaction, as their members are expected to form from similar material in their parental cloud. We present ALMA observations of the hierarchical proto-triple system HOPS-288, focusing on the physical structure, kinematics, and COM compositions. The system is treated as a proto-binary system consisting of HOPS-288-A and HOPS-288-B due to the limited spatial resolutions, with a separation of 200~au. Three COM-rich features are revealed: two hot corinos associated with the two members, rich in a variety of COMs, and an intervening component between the two members traced by CH$_3$OH and tentatively by CH$_3$CHO. The hot corino in HOPS-288-A exhibits rotational features and might trace a disk. The hot corino in HOPS-288-B is also possibly exhibiting rotational motion. The intervening component could possibly trace a shocked region in the circumbinary disk or a bridge between the two members. The column densities of COMs, including $^{13}$CH$_3$OH, CH$_2$DOH, CH$_3$CHO, HCOOCH$_3$, C$_2$H$_5$OH, $^{13}$CH$_3$CN, and NH$_2$CHO, are broadly similar between the two sources, possibly suggesting the complex organic similarities among proto-binary/multiple systems. Given the complexity of the studied physical structures, further detailed investigations will be essential to confirm this result.

astro-ph.SR

Unveiling Central ortho-H2D+ Depletion at Sub-kau Scales in Prestellar Core G205.46-14.56M3: The First Interferometric Evidence and Implications for Deuterium Chemistry

Prestellar cores represent the initial conditions of star formation, but heavy molecules such as CO are strongly depleted in their cold, dense interiors, limiting the ability to probe core centers. Deuterated molecular ions therefore emerge as key tracers because deuterium fractionation is enhanced at low temperatures. We present the first direct observation of ortho-H2D+ depletion in the prestellar core G205.46-14.56M3 using ALMA 820um continuum and ortho-H2D+(110-111) data at ~300-au resolution. We confirm the previously reported two substructures, B1 and B2, and identify a central ortho-H2D+ depletion zone toward B1 with ~6$σ$ contrast and an inferred diameter $\lesssim$600au, together with a peak $x$(N2D+)/$x$(N2H+)=$1.03^{+0.07}_{-0.56}$. The observationally inferred profiles of $x$(ortho-H2D+) and $x$(N2D+)/$x$(N2H+) are reproduced by a deuteration-focused chemo-dynamical model; however, the central ortho-H2D+ depletion is only marginally matched within the $2σ$ upper limit, likely suggesting additional deuteration in the depletion zone. From these models we infer a core age of ~0.42Ma, comparable to the free-fall time, suggesting that the substructures formed via rapid, turbulence-dominated fragmentation rather than slow, quasi-static contraction. Our observations also reveal that ortho-H2D+ velocity dispersions are largely subsonic in the core and nearly thermal between B1 and B2, consistent with turbulence dissipating within a few free-fall times. These results highlight the critical role of deuterated ions for both chemical evolution and dynamics in dense cores.

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Ubiquity of Methanol and its related Chemical Segregation in Orion Starless Cores: the ALMASOP Sample

Complex organic molecules (COMs) in starless cores provide critical insights into the early stages of star formation and prebiotic chemistry. We present a chemical survey of 16 starless cores (including five prestellar cores) in the Orion A and B molecular clouds, targeting CH3OH, N2H+, CCS, and c-C3HD, using the Atacama Compact Array (ACA) and the Yebes 40-m telescope. CH3OH was detected toward all targets, confirming its ubiquity in starless cores, consistent with previous surveys in Taurus and Perseus. ACA imaging shows that CH3OH, CCS, and c-C3HD generally trace the outer layers of the dense cores outlined by N2H+, each exhibiting distinct spatial distributions. Meanwhile, Comparison with Yebes data reveals an extended, flattened CH3OH component. CCS and c-C3HD tend to be detected or non-detected together across cores, while cores near dust-rich regions on a large scale often lack both, suggesting environmental influences linked to the interstellar radiation field. Within individual cores, CCS typically resides in an outer layer relative to c-C3HD. Our findings underscore the importance of high-resolution studies for understanding the origins and spatial differentiation of COMs and carbon-chain molecules in cold, quiescent environments.

astro-ph.SR

ALMASOP: Inner-Envelope Structures of Protostars Driving Nascent Jets

Protostellar jets provide valuable insight into the evolutionary stage and formation history of star-forming cores in their earliest phases. We investigated the inner envelope structures of three extremely young protostars, selected for having the shortest dynamical timescales in their outflows and jets. Our analysis is based on Atacama Large Millimeter/submillimeter Array (ALMA) observations of the N2D+, DCO+, DCN, C18O, CH3OH, and H2CO lines, along with 1.3 mm continuum data, obtained at two spatial resolutions of ~500 AU and 150 AU. By examining molecular depletion and sublimation patterns, emission extents at core-scale and outflow rotational temperatures, we assessed the relative evolutionary stages of the three sources. In G208.68-19.20N1, the absence of N2D+ toward the core-despite a semi-ring-like distribution-and the presence of bright DCN and DCO+ emission cospatial with C18O indicate a warmer envelope, possibly suggesting a more advanced evolutionary state. In contrast, G208.68-19.20N3 shows no dense central structures in C18O, DCN, DCO+, or N2D+, with emission instead appearing scattered around the continuum and along large-scale filaments, consistent with a likely younger stage than G208.68-19.20N1. The third source, G215.87-17.62M, exhibits compact C18O emission at the continuum peak, but spatially extended N2D+, DCN, and DCO+ along the continuum, pointing to a cooler envelope and likely the youngest stage among the three. This comparative analysis across three protostars demonstrates the effectiveness of molecular tracers for evolutionary staging, though variations in luminosity or accretion may also shape chemical morphologies. These results highlight the promise of broader surveys for advancing our understanding of early protostellar evolution.

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Probing the Physical and Chemical Characteristics of an Extremely Early Class 0 Protostar in G204.4-11.3A2-NE

We have observed the low-mass molecular cloud core G204.4-11.3A2-NE (G204NE) in the direction of Orion B giant molecular cloud with the Atacama Large Millimeter/submillimeter Array in Band 6. The $\rm 1.3\ mm$ continuum images and visibilities unveil a compact central structure with a radius of $\sim$12 au, while showing no signature of binarity down to 18 au. The bolometric temperature and luminosity of this source are derived to be ${\sim}$33 K and $\sim$1.15 $~L_{\odot}$, respectively. Chemical stratification is observed in dense gas tracers, with C$^{18}$O emission peaking at the continuum position surrounded by the spatially extended emission of N$_2$D$^+$ and DCO$^+$. This implies that the core is in a very early evolutionary stage in which $\rm CO$ depletion occurs in most regions except for a small area heated by the central source. The envelope kinematics indicates a rotating and infalling structure with a central protostar mass of 0.08-0.1 $M_{\odot}$. The protostar drives a collimated outflow traced by CO, SiO, SO, and H$_2$CO, with misaligned blueshifted and redshifted lobes exhibiting a pair of bow-like patterns. High-velocity jets, extending up to 720 au, are detected in CO, SiO, and SO lines. The jet launching region is likely within twice of the dust sublimation zone. The absence of a binary signature suggests the outflows and jets are driven by a single protostar, although a close binary cannot be ruled out. The observed deflection of the outflows and jet is likely due to turbulent accretion in a moderately magnetized core.

astro-ph.SR

Detection of CH3+ in the O-rich planetary nebula NGC 6302

Planetary nebulae are sites where ejected stellar material evolves into complex molecules, but the precise physical conditions and chemical routes that govern these processes are unclear. The presence of abundant carbon-rich molecules in O-rich environments poses particular challenges. Here we report the first detection of methyl cation (CH3+) in any planetary nebula, observed in the O-rich nebula NGC 6302 using JWST MIRI/MRS observations. CH3+ is a key driver of organic chemistry in UV-irradiated environments. Spatially resolved observations reveal that CH3+ is co-located with 12CO, H2, H II, HCO+, and Polycyclic aromatic hydrocarbons (PAHs). LTE modelling of the CH3+ emission yields excitation temperatures of 500-800K in the inner bubble and torus, rising to 1000-2000K in the outer bubble of NGC 6302, with column densities ranging from ~10^11 to 10^13 cm^-2. This detection demonstrates that hydrocarbon radical chemistry must be incorporated into planetary nebulae chemical models. Further near-IR observations are crucial to map different chemical networks operating in these environments.

astro-ph.GA

Unveiling Stellar Feedback and Cloud Structure in the $ρ$ Ophiuchi A Region with ALMA and JWST: Discovery of Substellar Cores, C$^{18}$O Striations, and Protostellar Outflows

In clustered star-forming regions, stellar feedback-such as HII regions/photon-dominated regions (PDRs), and protostellar jets/outflows-shapes cloud structures and influences star formation. Using high-resolution ALMA millimeter and JWST infrared data, we analyze the cloud structure and the impact of stellar feedback in the nearest dense cluster-forming region Oph A. All 6 known Class 0/I and 2 of 6 Flat Spectrum/Class II objects are detected in the 1.3 mm dust continuum. Additionally, we newly detected 7 substellar cores, three of which show compact near-infrared emission, suggesting they are young substellar objects. The remaining cores, with masses of 0.01 Msun and high densities, are likely gravitationally bound. They appear connected by faint CO finger-like structures extending from the triple Class 0 system VLA1623-2417 Aa+Ab+B, suggesting they may have been ejected from the close binary VLA1623 Aa+Ab. 12CO and near-infrared data reveal multiple protostellar outflows. From the comparison, we identified several new outflows/jets, and shocked structures associated to the GSS30 large bipolar bubble. Strong 12CO emission traces the eastern edge of the Oph A ridge, forming part of the expanding HII/PDR bubble driven by the nearby Herbig Be star S1. The northern ridge appears blown out, with warm gas flowing toward GSS 30, injecting additional turbulent momentum. Several C18O striations in the S1 bubble align with magnetic fields, and position-velocity diagrams show wave-like patterns, possibly reflecting magnetohydrodynamic waves. Stellar feedback significantly influences Oph A's cloud structure.

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The JWST/MIRI view of the planetary nebula NGC 6302 I.: a UV irradiated torus and a hot bubble triggering PAH formation

NGC 6302 is a spectacular bipolar planetary nebula (PN) whose spectrum exhibits fast outflows and highly ionized emission lines, indicating the presence of a very hot central star (~220,000 K). Its infrared spectrum reveals a mixed oxygen and carbon dust chemistry, displaying both silicate and polycyclic aromatic hydrocarbon (PAH) features. Using the JWST Mid-Infrared Instrument (MIRI) and Medium Resolution Spectrometer, a mosaic map was obtained over the core of NGC 6302, covering the wavelength range of 5--28 micron and spanning an area of ~18.5 arcsec x15 arcsec. The spatially resolved spectrum reveals ~200 molecular and ionized lines from species requiring ionisation potentials of up to 205 eV. The spatial distributions highlight a complex structure at the nebula's centre. Highly ionized species such as Mg VII and Si VII show compact structures, while lower-ionization species such as H^+ extend much farther outwards, forming filament-defined rims that delineate a bubble. Within the bubble, the H^+ and H_2 emission coincide, while the PAH emission appears farther out, indicating an ionization structure distinct from typical photodissociation regions, such as the Orion Bar. This may be the first identification of a PAH formation site in a PN. This PN appears to be shaped not by a steady, continuous outflow, but by a series of dynamic, impulsive bubble ejections, creating local conditions conducive to PAH formation. A dusty torus surrounds the core, primarily composed of large (micron-sized) silicate grains with crystalline components. The long-lived torus contains a substantial mass of material, which could support an equilibrium chemistry and a slow dust-formation process.

astro-ph.SR

ALMASOP. A Rotating Feature Rich in Complex Organic Molecules in a Protostellar Core

Interstellar complex organic molecules (COMs) in solar-like young stellar objects (YSOs), particularly within protostellar disks, are of significant interest due to their potential connection to prebiotic chemistry in emerging planetary systems. We report the discovery of a rotating feature enriched in COMs, including CH3OH, CH3CHO, and NH2CHO, in the protostellar core G192.12-11.10. By constructing a YSO model, we find that the COM-rich feature is likely located within or near the boundary of the Keplerian disk. The image synthesis results suggest that additional heating mechanisms leading to a warm ring or a warm inner disk are required to reproduce the observed emission. We discuss possible origins of the COM-rich feature, particularly accretion shocks as a plausible cause for a warm ring. Additionally, molecules such as C18O, H2CO, DCS, H2S, and OCS exhibit distinct behavior compared to CH3OH, indicating a range of physical and chemical conditions within the region. The observed kinematics of H2S and OCS suggest that OCS resides in regions closer to the central protostar than H2S, consistent with previous experimental studies.

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ALMASOP. Detection of Turbulence-induced Mass Assembly Shocks in Starless Cores

Star formation is a series of mass assembly processes and starless cores, those cold and dense condensations in molecular clouds, play a pivotal role as initial seeds of stars. With only a limited sample of known starless cores, however, the origin and growth of such stellar precursors had not been well characterized previously. Meanwhile, the recent discovery of CH$_3$OH emission, which is generally associated with desorbed icy mantle in warm regions, particularly at the periphery of starless cores also remains puzzling. We present sensitive ALMA (Band~3) observations (at 3~mm) toward a sample of newly identified starless cores in the Orion Molecular Cloud. The spatially resolved images distinctly indicate that the observed CH$_3$OH and N$_2$H$^+$ emission associated with these cores are morphologically anti-correlated and kinematically offset from each other. We postulate that the CH$_3$OH emission highlights the desorption of icy mantle by shocks resulting from gas piling onto dense cores in the filaments traced by N$_2$H$^+$. Our magnetohydrodynamic (MHD) simulations of star formation in turbulent clouds combined with radiative transfer calculations and imaging simulations successfully reproduced the observed signatures and reaffirmed the above scenario at work. Our result serves as an intriguing and exemplary illustration, a snapshot in time, of the dynamic star-forming processes in turbulent clouds. The results offer compelling insights into the mechanisms governing the growth of starless cores and the presence of gas-phase complex organic molecules associated with these cores.

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ALMA 2D Super-resolution Imaging Survey of Ophiuchus Class I/Flat Spectrum/II Disks -- I: Discovery of New Disk Substructures

This study focuses on Class I, Flat Spectrum (FS), and Class II disks in the Ophiuchus molecular cloud, a nearby active star-forming region with numerous young stellar objects (YSOs), to unveil signs of substructure formation in these disks. We employ two-dimensional super-resolution imaging based on Sparse Modeling (SpM) for ALMA archival Band 6 continuum data, achieving images with spatial resolutions comparable to a few au (0".02-0".2) for 78 dust disks, all of which are spatially resolved. In our sample, we confirm that approximately 30-40% of the disks exhibit substructures, and we identify new substructures in 15 disks (4 Class I, 7 Class FS, and 4 Class II objects). Compared to the eDisk sample in terms of bolometric temperature, Tbol, our targets are in a relatively later accretion phase. By combining our targets with the eDisk sample, we confirm that substructure detection in available data is restricted to objects where Tbol exceeds 200-300 K and the dust disk radius, Rdust, is larger than ~30 au. Moreover, we find that the distribution of inclination angles for Class II disks has a deficit of high values and is not consistent with being random. Analyzing molecular line emission data around these objects will be crucial to constrain disk evolutionary stages further and understand when and how substructures form.

astro-ph.EP

The magnetic field in quiescent star-forming filament G16.96+0.27

We present 850 μm thermal dust polarization observations with a resolution of 14.4"(~ 0.13 pc) towards an infrared dark cloud G16.96+0.27 using JCMT/POL-2. The average magnetic field orientation, which roughly agrees with the larger-scale magnetic field orientation traced by the Planck 353 GHz data, is approximately perpendicular to the filament structure. The estimated plane-of-sky magnetic field strength is ~ 96 μG and ~ 60 μG using two variants of the Davis-Chandrasekhar-Fermi methods. We calculate the virial and magnetic critical parameters to evaluate the relative importance of gravity, the magnetic field, and turbulence. The magnetic field and turbulence are both weaker than gravity, but magnetic fields and turbulence together are equal to gravity, suggesting that G16.96+0.27 is in a quasi-equilibrium state. The cloud-magnetic-field alignment is found to have a trend moving away from perpendicularity in the dense regions, which may serve as a tracer of potential fragmentation in such quiescent filaments.

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ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): Nested Morphological and Kinematic Structures of Outflows Revealed in SiO and CO Emission

The Atacama Large Millimeter/submillimeter Array Survey of Orion Planck Galactic Cold Clumps (ALMASOP) reveals complex nested morphological and kinematic features of molecular outflows through the CO (J = 2 - 1) and SiO (J = 5 - 4) emission. We characterize the jet and outflow kinematics of the ALMASOP sample in four representative sources (HOPS 10, 315, 358, and G203.21-11.20W2) through channel maps and position-velocity diagrams (PVDs) parallel and transverse to the outflow axes. The combined CO and SiO emission exhibits the coexistence of the conventional extremely-high-velocity (EHV) jets and shell-like low-velocity (LV) cavity walls and new features. More complex, nested bubble-like and filamentary structures in the images and channel maps, triangle-shaped regions near the base of the parallel PVDs, and regions composed of rhombus/oval shapes in the transverse PVDs, are also evident. Such features find natural explanations within the bubble structure of the unified model of jet, wind, and ambient medium. The reverse shock cavity is revealed on the PVD base regions, and other features naturally arise within the dynamic postshock region of magnetic interaction. The finer nested shells observed within the compressed wind region reveal previously unnoticed shocked emission between the jet and the conventional large cavity walls. These pseudopulse-produced filamentary features connect to the jet-like knotty blobs, creating an impression of episodicity in mass ejection. SiO emission is enhanced downstream of the reverse shock boundary, with jet-like excitation conditions. Combined, these observed features reveal the extended structures induced by the magnetic interplay between a jet-bearing magnetized wide-angle wind and its ambient magnetized surrounding medium.

astro-ph.SR

Q-band Line Survey Observations toward a Carbon-chain-rich Clump in the Serpens South Region

We have conducted Q-band (30 GHz $-$ 50 GHz) line survey observations toward a carbon-chain emission peak in the Serpens South cluster-forming region with the extended Q-band (eQ) receiver installed on the Nobeyama 45 m radio telescope. Approximately 180 lines have been detected including tentative detection, and these lines are attributed to 52 molecules including isotopologues. It has been found that this position is rich in carbon-chain species as much as Cyanopolyyne Peak in Taurus Molecular Cloud-1 (TMC-1 CP), suggesting chemical youth. Not only carbon-chain species, but several complex organic molecules (CH$_3$OH, CH$_3$CHO, HCCCHO, CH$_3$CN, and tentatively C$_2$H$_3$CN) have also been detected, which is similar to the chemical complexity found in evolved prestellar cores. The HDCS/H$_2$CS ratio has been derived to be $11.3 \pm 0.5$ %, and this value is similar to the prestellar core L1544. The chemically young features that are similar to the less-dense starless core TMC-1 CP ($10^4$ cm$^{-3}$ $-$ $10^5$ cm$^{-3}$) and chemically evolved characters which resemble the dense prestellar core L1544 ($\sim 10^6$ cm$^{-3}$) mean that the clump including the observed position is a pre-cluster clump without any current star formation activity.

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ALMASOP. The Localized and Chemically rich Features near the Bases of the Protostellar Jet in HOPS 87

HOPS 87 is a Class 0 protostellar core known to harbor an extremely young bipolar outflow and a hot corino. We report the discovery of localized, chemically rich regions near the bases of the two-lobe bipolar molecular outflow in HOPS 87 containing molecules such as H$_2$CO, $^{13}$CS, H$_2$S, OCS, and CH$_3$OH, the simplest complex organic molecule (COM). The locations and kinematics suggest that these localized features are due to jet-driven shocks rather than being part of the hot corino region encasing the protostar. The COM compositions of the molecular gas in these jet-localized regions are relatively simpler than those in the hot corino zone. We speculate that this simplicity is due to either the liberation of ice with a less complex chemical history or the effects of shock chemistry. Our study highlights the dynamic interplay between the protostellar bipolar outflow, disk, inner core environment, and the surrounding medium, contributing to our understanding of molecular complexity in solar-like young stellar objects.

astro-ph.SR