J/AJ/146/114 Massive stars in M101. I. HST BVI photometry (Grammer+, 2013)
The massive star population in M101.
I. The identification and spatial distribution of the visually luminous stars.
Grammer S., Humphreys R.M.
<Astron. J., 146, 114 (2013)>
=2013AJ....146..114G 2013AJ....146..114G
ADC_Keywords: Galaxies, nearby ; Photometry, HST ; Stars, luminous
Keywords: catalogs - galaxies: individual: M101 - galaxies: stellar content
Abstract:
An increasing number of non-terminal giant eruptions are being
observed by modern supernova and transient surveys. But very little is
known about the origin of these giant eruptions and their progenitors,
many of which are presumably very massive, evolved stars. Motivated by
the small number of progenitors positively associated with these giant
eruptions, we have begun a survey of the evolved massive star
populations in nearby galaxies. The nearby, nearly face-on, giant
spiral M101 is an excellent laboratory for studying a large population
of very massive stars. In this paper, we present BVI photometry
obtained from archival HST/ACS Wide Field Camera images of M101. We
have produced a catalog of luminous stars with photometric errors <10%
for V<24.5 and 50% completeness down to V∼26.5 even in regions of high
stellar crowding. Using color and luminosity criteria, we have
identified candidate luminous OB-type stars and blue supergiants,
yellow supergiants, and red supergiants for future observation. We
examine their spatial distributions across the face of M101 and find
that the ratio of blue to red supergiants decreases by two orders of
magnitude over the radial extent of M101 corresponding to 0.5 dex in
metallicity. We discuss the resolved stellar content in the giant
star-forming complexes NGC 5458, 5453, 5461, 5451, 5462, and 5449 and
discuss their color-magnitude diagrams in conjunction with the spatial
distribution of the stars to determine their spatio-temporal formation
histories.
Description:
Sixteen fields in M101 were imaged with the HST Advanced Camera for
Surveys (ACS) Wide Field Camera with F435W, F555W, and F814W filters
on 2002 November 13-16 and 2003 January 14-23 (proposal IDs 9490 and
9492).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 91 539825 M101 catalog from HST observations
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See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
J/AJ/141/126 : HST photometry of NGC 5471 (Garcia-Benito+, 2011)
J/ApJ/733/124 : Cepheids in M101 observed with HST (Shappee+, 2011)
J/MNRAS/357/401 : An XMM-Newton view of M101 (Jenkins+, 2005)
J/ApJ/508/491 : M101 Cepheids (Stetson+, 1998)
J/ApJ/463/26 : VI photometry of 29 Cepheids in M101. (Kelson+ 1996)
J/ApJS/73/661 : H II regions in M 101 (Hodge+ 1990)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- Star Source identifier (JHHMMSS.ss+DDMMSS.ss)
<[GH2013b] JHHMMSS.ss+DDMMSS.ss> in Simbad
22- 28 A7 --- Field Advanced Camera for Surveys (ACS) field number
30- 31 I2 h RAh Hour of Right Ascension (J2000)
33- 34 I2 min RAm Minute of Right Ascension (J2000)
36- 40 F5.2 s RAs Second of Right Ascension (J2000)
42- 43 I2 deg DEd Degree of Declination (J2000)
45- 46 I2 arcmin DEm Arcminute of Declination (J2000)
48- 52 F5.2 arcsec DEs Arcsecond of Declination (J2000)
54- 59 F6.3 mag Vmag The V band magnitude (F555W)
61- 65 F5.3 mag e_Vmag The 1σ uncertainty in Vmag
67- 72 F6.3 mag B-V The (B-V) color index (F435W-F555W)
74- 78 F5.3 mag e_B-V The 1σ uncertainty in B-V
80- 85 F6.3 mag V-I The (V-I) color index (F555W-F814W)
87- 91 F5.3 mag e_V-I The 1σ uncertainty in V-I
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 17-Jul-2014