Probing the inner 200 AU of low-mass protostars with the Submillimeter Array: Dust and organic molecules in NGC1333-IRAS2A

Abstract

The Submillimeter Array has opened a new window to study the innermost warm and dense regions of the envelopes and disks around deeply embedded protostars. This paper presents high-angular resolution (< 2'') submillimeter observations of the class 0 young stellar object NGC1333-IRAS2A. Dust continuum emission and lines of complex organic molecules such as CH3OCH3 and CH3OCHO, high excitation CH3OH transitions, deuterated methanol CH3OD as well as lines of CO, HCN, H13CN, SO and SO2 are detected on < 200 AU scales. The observations are interpreted using detailed radiative transfer models of the physical and chemical structure, consistent with both single-dish and interferometer data. The continuum emission is explained by an extended envelope and a compact but resolved component, presumably a circumstellar disk with a diameter of 200-300 AU and a mass of a few times 0.01-0.1 M_sun. If related to the rotation of the envelope, then the size of this disk suggests a centrifugal barrier of 200-300 AU, which implies that the temperature in the envelope does not increase above 100 K. Its large size also suggests that the build-up of disks proceeds rapidly throughout the early protostellar stages. The smaller (< 100 AU) disks found around other deeply embedded protostars may be a result of tidal truncation. The high-resolution observations of SO can be explained with a simple constant abundance, ~1E-9, constrained through single-dish observations, whereas those of H13CN and the organic species require high abundances, increased by one to two orders of magnitude, or an additional compact source of emission at small scales. The compact molecular emission could originate in a hot core region of the inner envelope, but a more likely reservoir is the circumstellar disk.

Accepted for publication in ApJ. 24 pages, 5 figures

References in corpus (16)

• An atomic and molecular database for analysis of submillimetre line observations
• The Submillimeter Array
• Molecular Inventories and Chemical Evolution of Low-mass Protostellar Envelopes
• Complex molecules in the hot core of the low mass protostar NGC1333-IRAS4A
• Organic molecules in protoplanetary disks around TTauri and HerbigAe stars
• Near-arcsecond resolution observations of the hot corino of the solar type protostar IRAS 16293-2422
• Evolution of Chemistry and Molecular Line Profile during Protostellar Collapse
• Resetting chemical clocks of hot cores based on S-bearing molecules
• The H2CO abundance in the inner warm regions of low mass protostellar envelopes
• Organic Molecules in Low-Mass Protostellar Hot Cores: Submillimeter Imaging of IRAS 16293-2422
• Molecular freeze-out as a tracer of the thermal and dynamical evolution of pre- and protostellar cores
• Imaging chemical differentiation around the low-mass protostar L483-mm
• H2CO and CH3OH abundances in the envelopes around low-mass protostars
• Physical-chemical modeling of the low-mass protostar IRAS 16293-2422
• On the origin of H2CO abundance enhancements in low-mass protostars
• IRAS 16293-2442B: A Compact, Possibly Isolated Protoplanetary Disk in a Class 0 Object

Cited by in corpus (85)

• Theory of Star Formation
• Protoplanetary Disks and Their Evolution
• The ALMA Protostellar Interferometric Line Survey (PILS): First results from an unbiased submillimeter wavelength line survey of the Class 0 protostellar binary IRAS 16293-2422 with ALMA
• PROSAC: A Submillimeter Array Survey of Low-Mass Protostars. I. Overview of Program: Envelopes, Disks, Outflows and Hot Cores
• PROSAC: A Submillimeter Array survey of low-mass protostars. II. The mass evolution of envelopes, disks, and stars from the Class 0 through I stages
• Constraining the abundances of complex organics in the inner regions of solar-type protostars
• A cold complex chemistry toward the low-mass protostar B1-b: evidence for complex molecule production in ices
• Chemical evolution of turbulent protoplanetary disks and the Solar nebula
• Hot corinos in NGC1333-IRAS4B and IRAS2A
• An interferometric study of the low-mass protostar IRAS 16293-2422: small scale organic chemistry
• Rotationally-supported disks around Class I sources in Taurus: disk formation constraints
• A recent accretion burst in the low-mass protostar IRAS 15398-3359: ALMA imaging of its related chemistry
• A Disk Around the Planetary-Mass Companion GSC 06214-00210 b: Clues About the Formation of Gas Giants on Wide Orbits
• 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
• Investigating grain growth in disks around southern T Tauri stars at millimetre wavelengths
• L483: Warm Carbon-Chain Chemistry Source Harboring Hot Corino Activity
• Complex organics in IRAS 4A revisited with ALMA and PdBI: Striking contrast between two neighbouring protostellar cores
• A break in the gas and dust surface density of the disc around the T Tauri star IM Lup
• Discovery of a Hot Corino in the Bok Globule B335
• Disk and Envelope Structure in Class 0 Protostars: II. High Resolution Millimeter Mapping of the Serpens Sample
• SMA observations of young disks: separating envelope, disk, and stellar masses in class I YSOs
• The Envelope and Embedded Disk around the Class 0 Protostar L1157-mm: Dual-wavelength Interferometric Observations and Modeling
• The deuterium fractionation of water on solar-system scales in deeply-embedded low-mass protostars
• Detection of glycolaldehyde towards the solar-type protostar NGC1333 IRAS2A
• Hot Corinos Chemical Diversity: Myth or Reality?
• Disk and Envelope Structure in Class 0 Protostars: I. The Resolved Massive Disk in Serpens FIRS 1
• Subarcsecond resolution observations of warm water towards three deeply embedded low-mass protostars
• The organic chemistry in the innermost, infalling envelope of the Class 0 protostar L483
• Warm water deuterium fractionation in IRAS 16293-2422 - The high-resolution ALMA and SMA view
• First detection of cyanamide (NH${}_2$CN) towards solar-type protostars
• A deeply embedded young protoplanetary disk around L1489 IRS observed by the submillimeter array
• The VLA Nascent Disk And Multiplicity (VANDAM) Survey of Perseus Protostars. Resolving the Sub-Arcsecond Binary System in NGC 1333 IRAS2A
• Physical and chemical fingerprint of protostellar disc formation
• ALMA observations of the kinematics and chemistry of disc formation
• Chemical complexity induced by efficient ice evaporation in the Barnard 5 molecular cloud
• Disks and Outflows in CO Rovibrational Emission from Embedded, Low-Mass Young Stellar Objects
• The ALMA-PILS survey: 3D modeling of the envelope, disks and dust filament of IRAS 16293-2422
• Chemistry of massive young stellar objects with a disk-like structure
• Observations of nitrogen isotope fractionation in deeply embedded protostars
• Herschel-HIFI observations of high-J CO lines in the NGC 1333 low-mass star-forming region
• The kinematics of NGC1333-IRAS2A - a true Class 0 protostar
• Protostellar accretion traced with chemistry. High resolution C18O and continuum observations towards deeply embedded protostars in Perseus
• OH far-infrared emission from low- and intermediate-mass protostars surveyed with Herschel-PACS
• Constraining the physical structure of the inner few 100 AU scales of deeply embedded low-mass protostars
• Tracing the cold and warm physico-chemical structure of deeply embedded protostars: IRAS 16293-2422 versus VLA 1623-2417
• Observational evidence for dissociative shocks in the inner 100 AU of low-mass protostars using Herschel-HIFI
• CoCCoA: Complex Chemistry in hot Cores with ALMA. Selected oxygen-bearing species
• Hot water in the inner 100 AU of the Class 0 protostar NGC1333 IRAS2A
• Implications of a hot atmosphere/corino from ALMA observations towards NGC1333 IRAS 4A1
• Constraining the Earliest Circumstellar Disks and their Envelopes
• First results from the CALYPSO IRAM-PdBI survey. I. Kinematics of the inner envelope of NGC1333-IRAS2A
• Intermediate-mass hot cores at 500 AU: disks or outflows?
• An Unbiased Spectral Line Survey toward R CrA IRS7B in the 345 GHz Window with ASTE
• Molecular CO outflows in the L1641-N cluster: kneading a cloud core
• Organic complexity in protostellar disk candidates
• Chemistry of a newly detected circumbinary disk in Ophiuchus
• ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): I. Detection of New Hot Corinos with ACA
• Large-scale numerical simulations of star formation put to the test: Comparing synthetic images and actual observations for statistical samples of protostars
• Evolution of CO lines in time-dependent models of protostellar disk formation
• Dimethyl ether in its ground state, v=0, and lowest two torsionally excited states, v11=1 and v15=1, in the high-mass star-forming region G327.3-0.6
• Imaging the water snowline in a protostellar envelope with H${}^{13}$CO${}^{+}$
• Probing the effects of external irradiation on low-mass protostars through unbiased line surveys
• Resolved molecular line observations reveal an inherited molecular layer in the young disk around TMC1A
• Hot corino chemistry in the Class I binary source Ser-emb 11
• Hunting for hot corinos and WCCC sources in the OMC-2/3 filament
• Water destruction by X-rays in young stellar objects
• The methanol lines and hot core of OMC2-FIR4, an intermediate-mass protostar, with Herschel-HIFI
• Characterizing the velocity field in hydrodynamical simulations of low-mass star formation using spectral line profiles
• A new, rotating hot corino in Serpens
• Complex molecules toward low-mass protostars: the Serpens core
• Linking the dust and chemical evolution: Taurus and Perseus -- New collisional rates for HCN, HNC, and their C, N, and H isotopologues
• Single-atom catalysis in space: Computational exploration of Fischer Tropsch reactions in astrophysical environments
• The chemical structure of the Class 0 protostellar envelope NGC 1333 IRAS 4A
• Complex Molecule Formation in Grain Mantles
• Star and Planet Formation with ALMA: an Overview
• Ices in starless and starforming cores
• Modelling carbon-chain species formation in lukewarm corinos with new multi-phase models
• Carbon-Chain and Organic Molecules around Very Low-Luminosity Protostellar Objects of L1521F-IRS and IRAM 04191+1522
• The molecular emission of the irradiated star forming core ahead of HH 80N
• SOLIS XVII: Jet candidate unveiled in OMC-2 and its possible link to the enhanced cosmic-ray ionisation rate
• PRODIGE VI -- Envelope to Disk with NOEMA: VI. The Missing Sulfur Problem
• Infrared action spectroscopy as tool for probing gas-phase dynamics: Protonated Dimethyl Ether, (CH${}_3$)${}_2$OH${}^{+}$, formed by the reaction of CH${}_3$OH${}_2^{+}$ with CH${}_3$OH
• Which molecule traces what: chemical diagnostics of protostellar sources
• On the Formation of Deuterated Methyl Formate in Hot Corinos