2015A&A...581A...5S


C.D.S. - SIMBAD4 rel 1.7 - 2020.07.14CEST18:37:25

2015A&A...581A...5S - Astronomy and Astrophysics, volume 581A, 5-5 (2015/9-1)

Star formation in the filament of S254-S258 OB complex: a cluster in the process of being created.

SAMAL M.R., OJHA D.K., JOSE J., ZAVAGNO A., TAKAHASHI S., NEICHEL B., KIM J.S., CHAUHAN N., PANDEY A.K., ZINCHENKO I., TAMURA M. and GHOSH S.K.

Abstract (from CDS):

Infrared dark clouds are ideal laboratories for studying the initial processes of high-mass star and star-cluster formation. We investigated the star formation activity of an unexplored filamentary dark cloud (size ∼5.7pcx1.9pc), which itself is part of a large filament (∼20pc) located in the S254-S258 OB complex at a distance of 2.5kpc. Using Multi-band Imaging Photometer (MIPS) Spitzer 24 µm data, we uncovered 49 sources with signal-to-noise ratios greater than 5. We identified 45 sources as candidate young stellar objects (YSOs) of Class I, flat-spectrum, and Class II natures. Additional 17 candidate YSOs (9 Class I and 8 Class II) are also identified using JHK and Wide-field Infrared Survey Explorer (WISE) photometry. We find that the protostar-to-Class II sources ratio (∼2) and the protostar fraction (∼70%) of the region are high. Comparison of the protostar fraction to other young clusters suggests that the star formation in the dark cloud possibly started only 1Myr ago. Combining the near-infrared photometry of the YSO candidates with the theoretical evolutionary models, we infer that most of the candidate YSOs formed in the dark cloud are low-mass (<2M). We examine the spatial distribution of the YSOs and find that majority of them are linearly aligned along the highest column density line (N(H2)∼1x1022cm–2) of the dark cloud along its long axis at the mean nearest-neighbour separation of ∼0.2 pc. Using the observed properties of the YSOs, physical conditions of the cloud and a simple cylindrical model, we explore the possible star formation process of this filamentary dark cloud and suggest that gravitational fragmentation within the filament should have played a dominant role in the formation of the YSOs. From the total mass of the YSOs, the gaseous mass associated with the dark cloud, and the surrounding environment, we infer that the region is presently forming stars at an efficiency of ∼3% and a rate ∼30M/Myr, and it may emerge in a richer cluster.

Abstract Copyright:

Journal keyword(s): stars: formation - infrared: stars - stars: pre-main sequence - techniques: photometric - HII regions - ISM: clouds

Nomenclature: Table 1: [SOJ2015] NN (Nos 1-49). Text: [SOJ2015] IRDC G192.76+00.10 N=1.

Status at CDS:   Tables of objects will be appraised for possible ingestion in SIMBAD.

Simbad objects: 20

goto Full paper

goto View the reference in ADS

Number of rows : 20

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 NGC 1333 OpC 03 29 11 +31 18.6           ~ 1219 1
2 IC 348 OpC 03 44 34 +32 09.8           ~ 1227 1
3 NAME Taurus Complex SFR 04 41.0 +25 52           ~ 3479 0
4 TKK 870 Y*O 05 35 28.19 -05 03 41.2           ~ 34 0
5 NAME Ori A MoC 05 38 -07.1           ~ 2675 0
6 LBN 192.48-00.21 HII 06 11 59 +18 03.3           ~ 85 0
7 SH 2-256 HII 06 12 36 +17 56.9           ~ 52 1
8 SH 2-257 HII 06 12 44 +17 59.3           ~ 121 1
9 NAME S254-258 complex SFR 06 12 48.0 +17 59 00           ~ 21 0
10 IC 2162 HII 06 13 04.1 +17 58 44           ~ 338 2
11 [CAH2008] G192.75-0.08 Cl* 06 13 05.0 +17 50 30           ~ 2 0
12 SH 2-258 HII 06 13 28 +17 55.5           ~ 67 0
13 [SOJ2015] IRDC G192.76+00.10 DNe 06 13.8 +17 55           ~ 3 0
14 SH 2-255 B HII 06 14 24.1 +17 45 13           ~ 9 0
15 NAME Cha II MoC 12 54 -77.2           ~ 296 0
16 ELAIS N1 reg 16 10 01 +54 30.6           ~ 309 0
17 [CCE98b] 011.11-0.12 Cld 18 10.5 -19 23           ~ 85 1
18 NAME Dragon Nebula DNe 18 42 50.6 -04 03 30           ~ 112 0
19 [PWC2006] NH3 G28.34+0.06 P1 cor 18 42 50.9 -04 03 14           ~ 37 0
20 NAME Gould Belt PoG ~ ~           ~ 711 1

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2015A&A...581A...5S and select 'bookmark this link' or equivalent in the popup menu


2020.07.14-18:37:25

© Université de Strasbourg/CNRS

    • Contact