J/ApJ/833/85 Multi-wavelength analysis of the MIR bubble N37 (Baug+, 2016)
Star formation around mid-infrared bubble N37: evidence of cloud-cloud
collision.
Baug T., Dewangan L.K., Ojha D.K., Ninan J.P.
<Astrophys. J., 833, 85-85 (2016)>
=2016ApJ...833...85B 2016ApJ...833...85B (SIMBAD/NED BibCode)
ADC_Keywords: Photometry, infrared ; Spectral types ; Extinction ; YSOs ;
Stars, OB ; Stars, ages ; Stars, masses ; Interstellar medium
Keywords: dust, extinction; H II regions; ISM: clouds;
ISM: individual objects: N37; stars: formation
Abstract:
We have performed a multi-wavelength analysis of a mid-infrared (MIR)
bubble N37 and its surrounding environment. The selected 15'x15' area
around the bubble contains two molecular clouds (N37 cloud;
Vlsr∼37-43km/s, and C25.29+0.31; Vlsr∼43-48km/s) along the line of
sight. A total of seven OB stars are identified toward the bubble N37
using photometric criteria, and two of them are spectroscopically
confirmed as O9V and B0V stars. The spectro-photometric distances of
these two sources confirm their physical association with the bubble.
The O9V star appears to be the primary ionizing source of the region,
which is also in agreement with the desired Lyman continuum flux
analysis estimated from the 20cm data. The presence of the expanding
HII region is revealed in the N37 cloud, which could be responsible
for the MIR bubble. Using the 13CO line data and photometric data,
several cold molecular condensations as well as clusters of young
stellar objects (YSOs) are identified in the N37 cloud, revealing
ongoing star formation (SF) activities. However, the analysis of ages
of YSOs and the dynamical age of the HII region do not support the
origin of SF due to the influence of OB stars. The position-velocity
analysis of 13CO data reveals that two molecular clouds are
interconnected by a bridge-like structure, favoring the onset of a
cloud-cloud collision process. The SF activities (i.e., the formation
of YSO clusters and OB stars) in the N37 cloud are possibly influenced
by the cloud-cloud collision.
Description:
We selected a large-scale region of 15'x15' (centered at
l=25.315°, b=0.278°) around the bubble N37, which also
contains an IRDC and a pillar-like structure.
We obtained the optical spectra of two point-like sources (V∼14mag)
using Grism 7 and Grism 8 of the Hanle Faint Object Spectrograph and
Camera (HFOSC; with a slit width of 167µm, the average spectral
resolution is ∼1000) attached to the 2m Himalayan Chandra Telescope
(HCT).
We obtained the multi-wavelength (NIR to radio) data from various
Galactic plane surveys. See section 2 for the details.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 98 7 Details of the photometrically identified OB stars
toward the N37 region
table2.dat 75 81 Physical parameters of selected YSOs derived from
the SED modeling
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See also:
II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)
II/316 : UKIDSS-DR6 Galactic Plane Survey (Lucas+ 2012)
II/293 : GLIMPSE Source Catalog (I + II + 3D) (IPAC 2008)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
III/195 : Atlas of Optical Spectral Classification OB Stars (Walborn+ 1990)
VII/50 : CO Radial Velocities Toward Galactic H II Regions (Blitz+ 1982)
J/MNRAS/447/2307 : Galactic HII region IRAS 16148-5011 content (Mallick+, 2015)
J/AJ/149/64 : MIPSGAL 24µm point source catalog (Gutermuth+, 2015)
J/A+A/569/A125 : Spiral structure of the Milky Way (Hou+, 2014)
J/ApJS/209/2 : The BGPS. X. Dense molecular gas (Shirley+, 2013)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/MNRAS/424/2442 : Catalog of bubbles from Milky Way Project (Simpson+, 2012)
J/A+A/544/A146 : ATLASGAL cold high-mass clumps with NH3 (Wienen+, 2012)
J/A+A/534/A114 : UBV photometry in RCW173 (Marco+, 2011)
J/A+A/505/405 : A catalogue of Spitzer dark clouds (Peretto+, 2009)
J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/ApJS/181/255 : CO in Galactic HII regions (Anderson+, 2009)
J/ApJ/670/428 : Bubbles in the galactic disk. II. (Churchwell+, 2007)
J/ApJ/654/316 : X-ray sources in IC 1396N (Getman+, 2007)
J/ApJ/649/759 : Bubbles in the galactic disk (Churchwell+, 2006)
J/A+A/457/637 : UBVJHK synthetic photom. of Galactic O stars (Martins+, 2006)
J/AJ/131/2525 : MAGPIS 20cm survey (Helfand+, 2006)
J/AJ/131/1574 : Infrared photometry of IC348 members (Lada+, 2006)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Seq OB star sequence number
3- 4 I2 h RAh [18] Hour of Right Ascension (J2000)
6- 7 I2 min RAm [36] Minute of Right Ascension (J2000)
9- 12 F4.1 s RAs Second of Right Ascension (J2000)
14 A1 --- DE- [-] Sign of the Declination (J2000)
15- 16 I2 deg DEd [6] Degree of Declination (J2000)
18- 19 I2 arcmin DEm [33/47] Arcminute of Declination (J2000)
21- 22 I2 arcsec DEs Arcsecond of Declination (J2000)
24- 28 F5.2 mag Jmag [10.1/15.3] UKIDSS/GPS v6 J magnitude
30- 34 F5.2 mag Hmag [9.6/13.5] UKIDSS/GPS v6 H magnitude
36- 40 F5.2 mag Kmag [9.3/12.6] UKIDSS/GPS v6 K magnitude
42- 46 F5.2 mag [3.6] [10.1/15.6] GLIMPSE Spitzer/IRAC 3.6 magnitude
48- 52 F5.2 mag [4.5] [9.6/13.6] GLIMPSE Spitzer/IRAC 4.5 magnitude
54- 58 F5.2 mag [5.8] [9.3/12.7] GLIMPSE Spitzer/IRAC 5.8 magnitude
60- 64 F5.2 mag [8.0] [8.1/12]? GLIMPSE Spitzer/IRAC 8.0 magnitude
66- 70 F5.2 mag Av [6.1/19.8] Extinction, V band,
Indebetouw et al. (2005ApJ...619..931I 2005ApJ...619..931I) law
72- 76 F5.2 mag JMag [-4.1/-1.7] Absolute J magnitude (1)
78- 82 F5.2 mag HMag [-3.9/-1.7] Absolute H magnitude (1)
84- 88 F5.2 mag KMag [-3.9/-1.6] Absolute K magnitude (1)
90- 96 A7 --- SpT MK spectral type
98 I1 --- f_SpT [1/2]? Flag on spectral type (2)
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Note (1): Absolute magnitudes calculated assuming a distance of 3.0kpc and
compared with those listed in Martins & Plez (2006, J/A+A/457/637, for
O stars), and Pecaut & Mamajek (2013, J/ApJS/208/9, for B stars).
Note (2): Flag on OB spectral type as follows:
1 = Spectroscopically identified O9V
2 = Spectroscopically identified B0V
See the "Description" section above.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh [18] Hour of Right Ascension (J2000)
4- 5 I2 min RAm [35/37] Minute of Right Ascension (J2000)
7- 10 F4.1 s RAs Second of Right Ascension (J2000)
12- 12 A1 --- DE- [-] Sign of the Declination (J2000)
13- 14 I2 deg DEd [6] Degree of Declination (J2000)
16- 17 I2 arcmin DEm [33/47] Arcminute of Declination (J2000)
19- 20 I2 arcsec DEs Arcsecond of Declination (J2000)
22 A1 --- Loc Flag on location (1)
24- 27 F4.2 [yr] logAge [3.5/7] Derived YSO age
29- 32 F4.2 [yr] e_logAge [0.01/1.3] Uncertainty in logAge
34- 38 F5.2 Msun Mass [0.9/14.6] Derived YSO mass
40- 43 F4.2 Msun e_Mass [0.08/2.5] Uncertainty in Mass
45- 48 F4.2 [Lsun] logLum [1.3/2] Derived log total luminosity
50- 53 F4.2 [Lsun] e_logLum [0.01/0.4] Uncertainty in logLum
55- 59 F5.2 mag Av [0.1/50] Derived Extinction, V band
61- 65 F5.2 mag e_Av [0.01/17] Uncertainty in Av
67- 75 A9 --- Class Objection evolutionary class
("Class I": 15 sources, "Class II": 54 sources
or "Flat Spec": 12 sources)
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Note (1): Flags (sent by the author) as follows:
C = YSOs located toward C1.
B = YSOs located toward the N37 bubble.
P = YSOs located toward the pillar.
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History:
From electronic version of the journal
Acknowledgments:
Tapas Baug [Tata Institute of Fundamental Research, India]
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 30-Mar-2017