2004A&A...428..723U


Query : 2004A&A...428..723U

2004A&A...428..723U - Astronomy and Astrophysics, volume 428, 723-739 (2004/12-4)

High-mass star formation within the bright-rimmed cloud SFO 79.

URQUHART J.S., THOMPSON M.A., MORGAN L.K. and WHITE G.J.

Abstract (from CDS):

We report Radio Recombination Line (RRL) and continuum observations toward the IRAS point source 16362-4845, embedded within the Bright-Rimmed Cloud (BRC) SFO 79, a small molecular cloud lying at the edge of the HII region RCW 108. High resolution observations of the H92α hydrogen recombination line and of the continuum emission (3.6 and 6cm) confirm the presence of a resolved Ultra Compact (UC) HII region embedded within the molecular cloud. The integrated radio fluxes suggest the source of the ionisation to be an O9 Zero Age Main Sequence (ZAMS) star. Millimetre observations of 12CO, 13CO and C18O (J=1-0) molecular lines reveal the presence of a molecular condensation offset ∼30" to the north of the IRAS position on the boundary of the UC HII region. Analysis of 2MASS data has led to the identification of a small IR cluster of Young Stellar Objects (YSOs) that are positionally coincident with the UC HII region, lying to the south east of the peak of the radio emission. Moreover, the UC HII region appears to be extended in the direction of the IR cluster, which suggests that the radio emission and the IR cluster are in some way related to each other. MSX 8.3µm and 21.3µm images have been used to trace the large scale structure of the BRC, revealing the presence of a Photo Dominated Region (PDR) and three embedded thermal sources within the molecular cloud. The PDR has a plane parallel morphology which correlates extremely well with the morphology of the ionised gas traced by the optical emission. The three thermal sources (labelled A, B, C) all lie at a similar projected distance from the interface between the HII region and the molecular gas of the cloud. Thermal sources A and C are positionally coincident with the IRAS point sources 16362-4845 and 16362-4841 respectively, both of which have IRAS colours consistent with the presence of UC HII regions. Given that UC HII regions are relatively short lived (∼105yrs) it is reasonable to suggest that these two UC HII regions are of a similar age. The alignment of the three thermal sources along a line parallel to the bright rim suggests that they could have been triggered by the propagation of a plane parallel shock through the cloud.

Abstract Copyright:

Journal keyword(s): stars: formation - ISM: individual object: RCW 108, SFO 79 - ISM: clouds - ISM: HII regions - ISM: reflection nebulae - infrared: ISM

Nomenclature: Fig.8, Table 8: [UTM2004] Star a (Nos a-s). Fig.9, Text: [UTM2004] Source A (Nos A-C).

Simbad objects: 37

goto Full paper

goto View the references 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 - 2021
#notes
1 NAME Orion-KL SFR 05 35 14.16 -05 22 21.5           ~ 2098 1
2 3FGL J1617.4-5846 AGN 16 17 17.8913859288 -58 48 07.860059063   18.23       ~ 107 1
3 Ass Ara OB 1 As* 16 39.5 -46 46           ~ 90 0
4 2MASS J16395123-4852035 Y*O 16 39 51.2387635871 -48 52 03.636485923           ~ 1 0
5 2MASS J16395182-4851415 Y*O 16 39 51.8271667912 -48 51 41.528851546           ~ 2 0
6 2MASS J16395241-4853089 Y*O 16 39 52.4096212176 -48 53 08.976700265           ~ 2 0
7 2MASS J16395370-4851461 Y*O 16 39 53.7142574972 -48 51 46.349941163           ~ 3 0
8 [AMR2003] E PoC 16 39.9 -48 55           ~ 2 0
9 2MASS J16395449-4852014 Y*O 16 39 54.498 -48 52 01.45           ~ 2 0
10 2MASS J16395598-4851482 Y*O 16 39 55.9797698921 -48 51 48.266639970           ~ 4 0
11 2MASS J16395662-4851366 Y*O 16 39 56.6269430816 -48 51 36.713622275           ~ 2 0
12 2MASS J16395828-4852287 Y*O 16 39 58.29 -48 52 28.8           ~ 2 0
13 2MASS J16395848-4852368 Y*O 16 39 58.4855006997 -48 52 36.695464604           ~ 3 0
14 2MASS J16395974-4851592 Y*O 16 39 59.746 -48 51 59.22           ~ 1 0
15 2MASX J16395987-4851524 Y*O 16 39 59.879 -48 51 52.41           ~ 1 0
16 Ass Ara R 1 As* 16 40 -50.0           ~ 6 0
17 CD-48 11039 * 16 40 00.0881210970 -48 46 58.371367304   11.32 10.92 11.092   B3V 22 0
18 GUM 53 HII 16 40 00.1 -48 51 45           ~ 89 1
19 MSX6C G336.4917-01.4741 Y*O 16 40 00.1259054084 -48 51 40.395041833           ~ 7 0
20 IRAS 16362-4845 MoC 16 40 00.1 -48 51 45           ~ 16 2
21 NAME RCW 108 IR Cluster Cl* 16 40 01 -48 52.0           ~ 13 0
22 PMN J1640-4851 Rad 16 40 01.1 -48 51 38           ~ 2 0
23 [SHJ87] IRS 18 Y*O 16 40 01.1486597631 -48 51 52.432730553           ~ 5 0
24 2MASS J16400125-4851454 Y*O 16 40 01.260 -48 51 45.46           ~ 3 0
25 2MASS J16400155-4851484 Y*O 16 40 01.55 -48 51 48.4           ~ 6 0
26 2MASS J16400163-4851532 Y*O 16 40 01.6440659154 -48 51 53.315192580           ~ 3 0
27 2MASS J16400381-4852547 Y*O 16 40 03.8177103295 -48 52 54.761829708           ~ 2 0
28 MSX5C G336.5233-01.4643 MIR 16 40 05.0 -48 49 53           ~ 1 0
29 2MASS J16400706-4850338 Y*O 16 40 07.0583402511 -48 50 33.740020128           ~ 1 0
30 2MASS J16401019-4851356 Y*O 16 40 10.20 -48 51 35.6           ~ 2 0
31 HD 150135 * 16 41 19.4437431640 -48 45 47.570366793 6.19 7.00 6.88 7.33   O6.5V((f))z 111 0
32 NGC 6193 OpC 16 41 20 -48 45.8           ~ 137 0
33 HD 150136 SB* 16 41 20.4156742370 -48 45 46.728092318 4.98 5.78 5.65 6.93   O3.5-4III(f*)+O6IV 176 0
34 HD 151082 * 16 47 28.1319203659 -48 19 10.077314496   8.82 7.20     M0III 10 0
35 NAME M 17 SW SFR 18 20 23.1 -16 11 43           ~ 258 0
36 QSO B1921-293 BLL 19 24 51.05595514 -29 14 30.1210524   18.71 18.21 15.07   ~ 738 0
37 ICRF J193925.0-634245 Sy2 19 39 25.02671 -63 42 45.6255   18.87 18.37 17.64   ~ 1038 1

To bookmark this query, right click on this link: simbad:objects in 2004A&A...428..723U and select 'bookmark this link' or equivalent in the popup menu


2021.09.27-05:17:31

© Université de Strasbourg/CNRS

    • Contact