2019A&A...626A..71A


C.D.S. - SIMBAD4 rel 1.7 - 2020.07.08CEST03:53:28

2019A&A...626A..71A - Astronomy and Astrophysics, volume 626A, 71-71 (2019/6-1)

Physical and chemical fingerprint of protostellar disc formation.

ARTUR DE LA VILLARMOIS E., JORGENSEN J.K., KRISTENSEN L.E., BERGIN E.A., HARSONO D., SAKAI N., VAN DISHOECK E.F. and YAMAMOTO S.

Abstract (from CDS):


Context. The structure and composition of emerging planetary systems are likely strongly influenced by their natal environment within the protoplanetary disc at the time when the star is still gaining mass. It is therefore essential to identify and study the physical processes at play in the gas and dust close to young protostars and investigate the chemical composition of the material that is inherited from the parental cloud.
Aims. The purpose of this paper is to explore and compare the physical and chemical structure of Class I low-mass protostellar sources on protoplanetary disc scales.
Methods. We present a study of the dust and gas emission towards a representative sample of 12 Class I protostars from the Ophiuchus molecular cloud with the Atacama Large Millimeter/submillimeter Array (ALMA). The continuum at 0.87 mm and molecular transitions from C17O, C34S, H13CO+, CH3OH, SO2, and C2H were observed at high angular resolution (0.4", ∼60au diameter) towards each source. The spectrally and spatially resolved maps reveal the kinematics and the spatial distribution of each species. Moreover, disc and stellar masses are estimated from the continuum flux and position-velocity diagrams, respectively.
Results. Six of the sources show disc-like structures in C17O, C34S, or H13CO+ emission. Towards the more luminous sources, compact emission and large line widths are seen for transitions of SO2 that probe warm gas (Eu∼200K). In contrast, C17O emission is detected towards the least evolved and less luminous systems. No emission of CH3OH is detected towards any of the continuum peaks, indicating an absence of warm CH3OH gas towards these sources.
Conclusions. A trend of increasing stellar mass is observed as the envelope mass decreases. In addition, a power-law relation is seen between the stellar mass and the bolometric luminosity, corresponding to a mass accretion rate of (2.4±0.6)x10–7M/yr for the Class I sources, with a minimum and maximum value of 7.5x10–8 and 7.6x10–7M/yr, respectively. This mass accretion rate is lower than the expected value if the accretion is constant in time and rather points to a scenario of accretion occurring in bursts. The differentiation between C17O and SO2 suggests that they trace different physical components: C17O traces the densest and colder regions of the disc-envelope system, while SO2 may be associated with regions of higher temperature, such as accretion shocks. The lack of warm CH3OH emission suggests that there is no hot-core-like region around any of the sources and that the CH3OH column density averaged over the disc is low. Finally, the combination of bolometric temperature and luminosity may indicate an evolutionarytrend of chemical composition during these early stages.

Abstract Copyright: © ESO 2019

Journal keyword(s): ISM: molecules - stars: formation - protoplanetary disks - astrochemistry - ISM: individual objects: Ophiuchus

Simbad objects: 37

goto Full paper

goto View the reference in ADS

Number of rows : 37

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 NAME LDN 1448-mm Y*O 03 25 38.83 +30 44 06.2           ~ 301 0
2 [JCC87] IRAS 2A Y*O 03 28 55.55 +31 14 36.7           ~ 390 3
3 [JCC87] IRAS 4A2 Y*O 03 29 10.413 +31 13 32.20           ~ 81 1
4 [JCC87] IRAS 4A Y*O 03 29 10.49 +31 13 30.8           ~ 596 1
5 [JCC87] IRAS 4B Y*O 03 29 12.058 +31 13 02.05           ~ 553 0
6 IRAS 04016+2610 Y*O 04 04 43.07064 +26 18 56.3904           ~ 235 0
7 RAFGL 5123 FU* 04 31 34.07736 +18 08 04.9020           K3V/M3III 811 0
8 2MASS J04314444+1808315 Y*O 04 31 44.44680 +18 08 31.5384           ~ 149 0
9 LDN 1536 DNe 04 33 24.6 +22 43 29           ~ 94 0
10 IRAS 04361+2547 Y*O 04 39 13.89767 +25 53 20.6340           ~ 185 1
11 IRAS 04365+2535 Y*O 04 39 35.19360 +25 41 44.7252           ~ 237 0
12 IRAS 04368+2557 Y*O 04 39 53.97816 +26 03 09.6804           ~ 237 0
13 TMC-1 MoC 04 41 45.9 +25 41 27           ~ 1359 0
14 HH 212 HH 05 43 51.41 -01 02 53.1           ~ 280 1
15 QSO B1514-24 BLL 15 17 41.8135246339 -24 22 19.482167214   15.13 14.00 13.95   ~ 643 3
16 QSO B1622-253 QSO 16 25 46.89164010 -25 27 38.3267989   21.3 20.6 19.60   ~ 301 1
17 [EDJ2009] 800 Y*? 16 26 14.63 -24 25 07.5           ~ 11 0
18 GSS 30 Y*O 16 26 21.38160 -24 23 04.0524           ~ 200 1
19 [GY92] 30 Y*O 16 26 25.48920 -24 23 01.5576           ~ 37 0
20 VSSG 30 Y*O 16 26 44.19504 -24 34 48.3492           ~ 128 0
21 SSTc2d J162659.1-243503 Y*? 16 26 59.10 -24 35 03.3           ~ 11 0
22 WL 22 TT* 16 26 59.16720 -24 34 58.8072           ~ 64 0
23 [GY92] 197 Y*O 16 27 05.24616 -24 36 29.7936           ~ 58 1
24 Elia 2-29 Y*O 16 27 09.43032 -24 37 18.7716           ~ 267 1
25 [GRC2000] VLA 2 Rad 16 27 26.936 -24 40 50.63           ~ 13 0
26 YLW 15 Y*O 16 27 26.93640 -24 40 50.8224           ~ 240 1
27 YLW 16 IR 16 27 28 -24 39.5           ~ 18 0
28 YLW 16A Y*O 16 27 28.02744 -24 39 33.5052           K8 185 0
29 NAME Ophiuchus Molecular Cloud SFR 16 28 06 -24 32.5           ~ 3027 0
30 IRAS 16253-2429 FIR 16 28 22.2 -24 36 31           ~ 30 0
31 IRAS 16285-2355 Y*O 16 31 35.65752 -24 01 29.4708           ~ 103 0
32 ISO-Oph 203 Y*O 16 31 52.44696 -24 55 36.0804           ~ 12 0
33 WLY 2-67 Y*O 16 32 00.99624 -24 56 41.9640           ~ 55 0
34 IRAS 16293-2422 cor 16 32 22.56 -24 28 31.8           ~ 1035 1
35 V* R CrA Ae* 19 01 53.6850227874 -36 57 08.145519972 12.781 12.651 11.917 11.242 10.412 B5IIIpe 449 1
36 [NWA2005] SMM 1B Y*O 19 01 56.41 -36 57 28.0           ~ 78 1
37 QSO B1921-293 BLL 19 24 51.05595514 -29 14 30.1210524   18.71 18.21 15.07   ~ 689 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2019A&A...626A..71A and select 'bookmark this link' or equivalent in the popup menu


2020.07.08-03:53:28

© Université de Strasbourg/CNRS

    • Contact