2011A&A...529A..76R


C.D.S. - SIMBAD4 rel 1.7 - 2020.02.20CET02:56:05

2011A&A...529A..76R - Astronomy and Astrophysics, volume 529A, 76-76 (2011/5-1)

Hot HCN around young massive stars at 0.1'' resolution.

ROLFFS R., SCHILKE P., WYROWSKI F., DULLEMOND C., MENTEN K.M., THORWIRTH S. and BELLOCHE A.

Abstract (from CDS):

Massive stars form deeply embedded in dense molecular gas, which they stir and heat up and ionize. During an early phase, the ionization is confined to hypercompact HII regions, and the stellar radiation is entirely absorbed by dust, giving rise to a hot molecular core. To investigate the innermost structure of such high-mass star-forming regions, we observed vibrationally excited HCN (via the direct l-type transition of v2=1, ΔJ=0, J=13, which lies 1400K above ground) toward the massive hot molecular cores G10.47+0.03, SgrB2-N, and SgrB2-M with the Very Large Array (VLA) at 7mm, reaching a resolution of about 1000AU (0.1''). We detect the line both in emission and in absorption against HII regions. The latter allows to derive lower limits on the column densities of hot HCN, which are several times 1019cm–2. We see indication of expansion motions in G10.47+0.03 and detect velocity components in SgrB2-M at 50, 60, and 70km/s relative to the Local Standard of Rest. The emission originates in regions of less than 0.1pc diameter around the hypercompact HII regions G10.47+0.03 B1 and SgrB2-N K2, and reaches brightness temperatures of more than 200K. Using the three-dimensional radiative transfer code RADMC-3D, we model the sources as dense dust cores heated by stars in the HII regions, and derive masses of hot (>300K) molecular gas of more than 100 solar masses (for an HCN fractional abundance of 10–5), challenging current simulations of massive star formation. Heating only by the stars in the HII regions is sufficient to produce such large quantities of hot molecular gas, provided that dust is optically thick to its own radiation, leading to high temperatures through diffusion of radiation.

Abstract Copyright:

Journal keyword(s): ISM: molecules - ISM: structure - ISM: clouds - stars: formation

Simbad objects: 34

goto Full paper

goto View the reference in ADS

Number of rows : 34

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 W 3(H2O) Mas 02 27 04.6 +61 52 25           ~ 119 0
2 RAFGL 618 pA* 04 42 53.6245215366 +36 06 53.397219192   16.32   12.59   C-rich 946 0
3 NAME Orion-KL SFR 05 35 14.16 -05 22 21.5           ~ 1968 1
4 3C 279 QSO 12 56 11.1664521013 -05 47 21.531840471   18.01 17.75 15.87   ~ 2661 2
5 3C 286 Sy1 13 31 08.2885060664 +30 30 32.960825108   17.51 17.25     ~ 3659 1
6 IC 4553 SyG 15 34 57.22396 +23 30 11.6084   14.76 13.88     ~ 2647 4
7 QSO B1730-130 QSO 17 33 02.70578476 -13 04 49.5481484   18 18.5 18.78   ~ 969 1
8 NAME Sgr A* X 17 45 40.03599 -29 00 28.1699           ~ 3346 3
9 NAME Gal Center reg 17 45 40.04 -29 00 28.1           ~ 11251 0
10 NAME Sgr B2 HII K1 HII 17 47 19.8 -28 22 21           ~ 24 0
11 NAME Sgr B2 HII K2 HII 17 47 19.88 -28 22 18.4           ~ 21 0
12 NAME Sgr B2 HII K3 HII 17 47 19.90 -28 22 17.3           ~ 22 0
13 NAME Sgr B2 HII K4 HII 17 47 20.00 -28 22 04.8           ~ 17 0
14 NAME Sgr B2 HII F1 HII 17 47 20.12 -28 23 04.2           ~ 22 0
15 [BJ84] F1c HII 17 47 20.1293 -28 23 03.861           ~ 5 0
16 [BJ84] F1e HII 17 47 20.1329 -28 23 04.204           ~ 4 0
17 [BJ84] F1f HII 17 47 20.1520 -28 23 03.853           ~ 4 0
18 NAME Sgr B2 HII F2 HII 17 47 20.16 -28 23 03.9           ~ 21 0
19 NAME Sgr B2 HII F3 HII 17 47 20.18 -28 23 04.9           ~ 21 0
20 NAME Sgr B2 (North) Rad 17 47 20.2 -28 22 21           ~ 504 1
21 NAME Sgr B2 HII F4 HII 17 47 20.22 -28 23 04.4           ~ 21 0
22 NAME Sgr B2 MoC 17 47 20.4 -28 23 07           ~ 1879 1
23 NAME Sgr B2 Main Rad 17 47 20.5 -28 23 06           ~ 327 1
24 PMN J1755-2232 Rad 17 55 26.28477177 -22 32 10.6166169           ~ 23 0
25 [GRM93] G10.46+0.03 A HII 18 08 38.19 -19 51 49.4           ~ 9 0
26 [WC89] 010.47+0.03B2 HII 18 08 38.22 -19 51 50.5           ~ 6 0
27 [WC89] 010.47+0.03B1 HII 18 08 38.25 -19 51 50.1           ~ 7 0
28 GAL 010.47+00.03 HII 18 08 38.4 -19 51 52           ~ 108 0
29 IRAS 18449-0115 cor 18 47 34.4947 -01 12 40.269           ~ 299 0
30 OH 34.26 +0.15 SFR 18 53 18.54 +01 14 57.9           ~ 456 0
31 [WBN74] W 51 IRS 2 SFR 19 23 40.05 +14 31 07.1           ~ 252 0
32 NAME W 51 IRS 1 PoC 19 23 41.9 +14 30 36           ~ 95 0
33 NGC 7027 PN 21 07 01.8 +42 14 10   9.1 10.9     ~ 2308 1
34 3C 454.3 QSO 22 53 57.74798 +16 08 53.5611   16.57 16.10 15.22   ~ 2466 2

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2011A&A...529A..76R and select 'bookmark this link' or equivalent in the popup menu


2020.02.20-02:56:05

© Université de Strasbourg/CNRS

    • Contact