FAUST VII. Detection of A Hot Corino in the Prototypical Warm Carbon-Chain Chemistry Source IRAS 15398-3359

Abstract

We have observed the low-mass protostellar source, IRAS 15398$-$3359, at a resolution of 0.${}^{\prime \prime }$2-0.${}^{\prime \prime }$3, as part of the Atacama Large Millimeter/Submillimeter Array Large Program FAUST, to examine the presence of a hot corino in the vicinity of the protostar. We detect nine CH${}_3$OH lines including the high excitation lines with upper state energies up to 500 K. The CH${}_3$OH rotational temperature and the column density are derived to be 119${}_{-26}^{+20}$ K and 3.2${}_{-1.0}^{+2.5}\times$10${}^{18}$ cm${}^{-2}$, respectively. The beam filling factor is derived to be 0.018${}_{-0.003}^{+0.005}$, indicating that the emitting region of CH${}_3$OH is much smaller than the synthesized beam size and is not resolved. The emitting region of three high excitation lines, 18${}_{3,15}-18_{2,16}$, A ($E_u=$447 K), 19${}_{3,16}-19_{2,17}$, A ($E_u=$491 K), and 20${}_{3,17}-20_{2,18}$, A ($E_u=$537 K), is located within the 50 au area around the protostar, and seems to have a slight extension toward the northwest. Toward the continuum peak, we also detect one emission line from CH${}_2$DOH and two features of multiple CH${}_3$OCHO lines. These results, in combination with previous reports, indicate that IRAS 15398$-$3359 is a source with hybrid properties showing both hot corino chemistry rich in complex organic molecules on small scales $\sim$10 au) and warm carbon-chain chemistry (WCCC) rich in carbon-chain species on large scales ($\sim$100-1000 au). A possible implication of the small emitting region is further discussed in relation to the origin of the hot corino activity.

arXiv comment20pages, 3figures

References in corpus (60)

• The Cologne Database for Molecular Spectroscopy, CDMS, in the Virtual Atomic and Molecular Data Centre, VAMDC
• Tracing the Mass during Low-Mass Star Formation. I. Submillimeter Continuum Observations
• Water in star-forming regions with Herschel (WISH): II. Evolution of 557 GHz 110-101 emission in low-mass protostars
• A Large Catalog of Accurate Distances to Local Molecular Clouds: The Gaia DR2 Edition
• Molecular Evolution and Star Formation: From Prestellar Cores to Protostellar Cores
• Complex molecules in the hot core of the low mass protostar NGC1333-IRAS4A
• The ALMA-PILS survey: Isotopic composition of oxygen-containing complex organic molecules toward IRAS 16293-2422B
• Chemical Processes in Protoplanetary Disks
• Constraining the abundances of complex organics in the inner regions of solar-type protostars
• The earliest phases of star formation - A Herschel key project. The thermal structure of low-mass molecular cloud cores
• A protostellar system fed by a streamer of 10,500 au length
• UV photodesorption of methanol in pure and CO-rich ices: desorption rates of the intact molecule and of the photofragments
• Signs of Early-Stage Disk Growth Revealed with ALMA
• The ALMA-PILS survey: Inventory of complex organic molecules towards IRAS 16293-2422 A
• Infalling-Rotating Motion and Associated Chemical Change in the Envelope of IRAS 16293-2422 Source A Studied with ALMA
• The Perseus ALMA Chemistry Survey (PEACHES). I. The Complex Organic Molecules in Perseus Embedded Protostars
• A recent accretion burst in the low-mass protostar IRAS 15398-3359: ALMA imaging of its related chemistry
• The ALMA-PILS survey: Complex nitriles towards IRAS 16293--2422
• Formation and Atmosphere of Complex Organic Molecules of the HH 212 Protostellar Disk
• APEX-CHAMP+ high-J CO observations of low-mass young stellar objects: IV. Mechanical and radiative feedback
• First results from the CALYPSO IRAM-PdBI survey. II. Resolving the hot corino in the Class 0 protostar NGC 1333-IRAS2A
• Complex organic molecules in low-mass protostars on solar system scales -- I. Oxygen-bearing species
• The negligible photodesorption of methanol ice and the active photon-induced desorption of its irradiation products
• Chemical differentiation in a prestellar core traces non-uniform illumination
• PRODIGE -- Envelope to disk with NOEMA I. A 3000 au streamer feeding a Class I protostar
• L483: Warm Carbon-Chain Chemistry Source Harboring Hot Corino Activity
• Distances and Kinematics of Gould Belt Star-Forming Regions with Gaia DR2 results
• Discovery of a Hot Corino in the Bok Globule B335
• The observed chemical structure of L1544
• Hot Corinos Chemical Diversity: Myth or Reality?
• A Substellar-Mass Protostar and its Outflow of IRAS 15398-3359 Revealed by Subarcsecond-Resolution Observations of H${}_2$CO and CCH
• The organic chemistry in the innermost, infalling envelope of the Class 0 protostar L483
• Complex organic molecules in low-mass protostars on Solar System scales -- II. Nitrogen-bearing species
• A 100 au-Wide Bipolar Rotating Shell Emanating From The HH 212Protostellar Disk: A Disk Wind?
• Chemical survey toward young stellar objects in the Perseus molecular cloud complex
• FAUST I. The hot corino at the heart of the prototypical Class I protostar L1551 IRS5
• Chemical Variation among Protostellar Cores: Dependence on Prestellar Core Conditions
• Implications of a hot atmosphere/corino from ALMA observations towards NGC1333 IRAS 4A1
• Interferometric observations of warm deuterated methanol in the inner regions of low-mass protostars
• FAUST II. Discovery of a Secondary Outflow in IRAS 15398-3359: Variability in Outflow Direction during the Earliest Stage of Star Formation?
• ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): A Hot Corino Survey toward Protostellar Cores in the Orion Cloud
• The Co-evolution of Disk and Star in Embedded Stages: The Case of the Very Low-mass Protostar
• Constraining the Infalling Envelope Models of Embedded Protostars: BHR 71 and its Hot Corino
• FAUST III. Misaligned rotations of the envelope, outflow, and disks in the multiple protostellar system of VLA 1623$-$2417
• Organic chemistry in the protosolar analogue HOPS-108: Environment matters
• Physics of Outflows: the Binary Protostar L1551 IRS5 and its Jets
• Water around IRAS15398-3359 observed with ALMA
• A young bipolar outflow from IRAS 15398-3359
• Importance of source structure on complex organics emission. I. Observations of CH${}_3$OH from low-mass to high-mass protostars
• Distribution of methanol and cyclopropenylidene around starless cores
• Importance of source structure on complex organics emission II. Can disks explain lack of methanol emission from some low-mass protostars?
• Dust hot spots at 10 au scales around the Class 0 binary IRAS 16293-2422 A: a departure from the passive irradiation model
• Probing the effects of external irradiation on low-mass protostars through unbiased line surveys
• Chemical Differentiation and Temperature Distribution on a Few au Scale around the Protostellar Source B335
• Hot methanol in the [BHB2007] 11 protobinary system: hot corino versus shock origin? : FAUST V
• Outflows, envelopes, and disks as evolutionary indicators in Lupus YSOs
• Chemical and Physical Characterization of the Isolated Protostellar Source CB68: FAUST. IV
• Molecular Distributions of the Protostellar Envelope and the Outflow of IRAS 15398-3359: Principal Component Analysis
• On the origin of C${}_4$H and CH${}_3$OH in protostellar envelopes
• FAUST VI. VLA 1623--2417 B: a new laboratory for astrochemistry around protostars on 50 au scale

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• Evolution of Chemistry in the envelope of Hot Corinos (ECHOS). I. Extremely young sulphur chemistry in the isolated Class 0 object B335
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• Carbon chain diversity in L1544 and IRAS 16293-2422: an astrochemical pathfinder study for the SKAO