J/ApJ/670/428 Bubbles in the galactic disk. II. (Churchwell+, 2007)
The bubbling galactic disk. II. The inner 20°.
Churchwell E., Watson D.F., Povich M.S., Taylor M.G., Babler B.L.,
Meade M.R., Benjamin R.A., Indebetouw R., Whitney B.A.
<Astrophys. J., 670, 428-441 (2007)>
=2007ApJ...670..428C 2007ApJ...670..428C
ADC_Keywords: Galactic plane; H II regions; Morphology
Keywords: H II regions - ISM: bubbles - stars: formation
Abstract:
We report 269 mid-infrared bubbles within 10° of the Galactic
center from visual inspection of the Spitzer GLIMPSE II Legacy Science
program images. The surface density of bubbles is ∼5deg-2 or about 3
times that detected in longitudes |l|=10°-65°, because the
inner 10° of longitude were more thoroughly searched for small
bubbles. There is a gradient in the number of bubbles with longitude
with an increase of about a factor of 2 from 2° to 10°; this
is probably the result of several factors, including decreasing
diffuse background brightness, confusion, and opacity with longitude.
Bubble eccentricities are typically between 0.6 and 0.8, and >50% show
evidence for blowouts, which we suggest result from local density
fluctuations of the ISM and/or anisotropic stellar winds and radiation
fields.
Description:
In addition to the GI and GII data, Susan Stolovy has given us
permission to include her Spitzer/IRAC survey of an area of
0.75°x0.75° centered on the Galactic center (PID 3677 GO
program). The properties of the image mosaics from which bubbles were
identified have been described in Paper I, Churchwell et al., 2006,
Cat. J/ApJ/649/759.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 73 151 Northern Bubble parameters
table2.dat 68 118 Southern Bubble parameters
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See also:
J/ApJ/649/759 : The bubbling galactic disk. I (Churchwell+, 2006)
Byte-by-byte Description of file: table?.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- [CWP2007] Catalog name, CN NNN or CS NNN (1)
8- 14 F7.3 deg GLON Galactic longitude of center position
16- 21 F6.3 deg GLAT Galactic latitude center position
23- 26 F4.2 arcmin Rin Semimajor axis of the inner ellipse
28- 31 F4.2 arcmin rin Semiminor axis of the inner ellipse
33- 37 F5.2 arcmin Rout Semimajor axis of the outer ellipse
39- 42 F4.2 arcmin rout Semiminor axis of the outer ellipse
44- 47 F4.2 --- Ecc Eccentricity of the ellipses (2)
49- 52 F4.2 arcmin Average radius of the bubble
54- 57 F4.2 arcmin Average thickness of the shell
59- 73 A15 --- MFlags Morphology flags (3)
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Note (1): Catalog number preceded by CN if longitude is between 10° and
0°, and CS if longitude is between 360° and 350°.
Note (2): The centers and eccentricities of the inner and outer ellipses
are constrained to be the same.
Note (3): Morphology flags as follows:
C = complete or closed ring
B = broken or incomplete ring
CC = probable enclosed central star cluster, meaning that the stellar
density inside the ring appears to be greater than the average
stellar density outside the ring
BC = complex of two or more bubbles, that may or may not be
physically associated
MB = Bubbles that have at least one secondary bubble projected
within or on its periphery
MBm = Bubbles subsidiary to MB bubbles are labeled m(catalog number)
according to the MB bubble they are associated with
Y = Bubbles that have possible YSO(s) projected within or on its
periphery but have not formed a secondary bubble
CS = the central star(s) responsible for driving the
bubble is/are probably apparent
Fl = a flocculent or clumpy bubble structure
PN = Two bubbles that are probable planetary nebulae
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History:
From electronic version of the journal
References:
Churchwell et al., Paper I 2006ApJ...649..759C 2006ApJ...649..759C Cat. J/ApJ/649/759
(End) Patricia Vannier [CDS] 30-Jan-2010