J/AJ/138/606 Hot subdwarf stars in rejected PG catalog (Wade+, 2009)
Hot subdwarf stars among the objects rejected from the PG catalog:
a first assessment using GALEX photometry.
Wade R.A., Stark M.A., Green R.F., Durrell P.R.
<Astron. J., 138, 606-614 (2009)>
=2009AJ....138..606W 2009AJ....138..606W
ADC_Keywords: Stars, subdwarf ; Photometry, ultraviolet
Keywords: binaries: close - stars: horizontal-branch - subdwarfs -
ultraviolet: stars
Abstract:
The hot subdwarf (sd) stars in the Palomar Green (PG) catalog of
ultraviolet excess (UVX) objects play a key role in investigations of
the frequency and types of binary companions and the distribution of
orbital periods. These are important for establishing whether and by
which channels the sd stars arise from interactions in close binary
systems. It has been suggested that the list of PG sd stars is biased
by the exclusion of many stars in binaries, whose spectra show the
CaII K line in absorption. A total of 1125 objects that were
photometrically selected as candidates were ultimately rejected from
the final PG catalog using this K-line criterion. We study 88 of these
"PG-Rejects" (PGRs), to assess whether there are significant numbers
of unrecognized sd stars in binaries among the PGR objects.
Description:
GALEX Release 2/3 was most recently interrogated in 2008 May, using
the cross-correlation search page of the Multimission Archive at Space
Telescope (MAST).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 43 88 PGR sources and 2MASS counterparts
table2.dat 75 88 GALEX and V-band photometry of PGR objects
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See also:
II/207 : Palomar-Green catalog UV-excess stellar objects (Green+ 1986)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [PGR]
5- 15 A11 --- PGR Palomar Green Rejects name (JHHMMm+DDMM)
17- 21 A5 --- --- [2MASS]
23- 39 A17 --- 2MASS 2MASS designation (JHHMMSSss+DDMMSSs)
41- 43 A3 --- n_PGR Additional note(s) for PGR (1)
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Note (1): Notes as follows:
1 = Positional offset between USNO-A2 and 2MASS exceeds 1.5"
(80th percentile of offset size)
2 = There is a second 2MASS object within 10" of the USNO position
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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- 3 A3 --- --- [PGR]
5- 15 A11 --- PGR Palomar Green Rejects name (JHHMMm+DDMM)
17- 21 F5.2 mag Fmag Galex FUV band AB magnitude
23- 26 F4.2 mag e_Fmag ? The 1σ error in Fmag (1)
28- 32 F5.2 mag Nmag Galex NUV band AB magnitude
34- 37 F4.2 mag e_Nmag The 1σ error in Nmag
39- 42 F4.1 mag Vmag V band magnitude
44 A1 --- r_Vmag [A-D] Reference for Vmag (2)
46 A1 --- l_F-N Limit flag on F-N
48- 52 F5.2 mag F-N Galex FUV-NUV color index (1)
54- 57 F4.2 mag N-V The NUV-V color index
59- 63 F5.3 mag E(B-V) The B-V color excess (3)
65- 69 F5.2 mag (N-V)0 Dereddened NUV-V color index (4)
71- 75 A5 --- Notes Additional note(s) (5)
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Note (1): If no error is reported, then Fmag is an upper limit and thus
the (F-N) color is also a limit.
Note (2): References as follows:
A = Estimated with USNO-A2 data as: V=RUSNO+0.32(BUSNO-RUSNO)+0.23
B = Estimatid with SDSS data as V=g-0.58(g-r)-0.01
C = photoelectric UBV photometry carried out by R.F.G. during the
original PG survey
D = photoelectric CCD photometry in V and I by the All Sky Automated
Survey (ASAS; Pojmanski 2002, Cat. II/264)
Note (3): From Schlegel et al. (1998ApJ...500..525S 1998ApJ...500..525S), as returned by the
MAST query.
Note (4): Using E(N-V)=4.8xE(B-V).
Note (5): Notes as follows:
LOCK = Lockman hole observation
GI = Guest Investigator observation
MIS = Medium Imaging Survey observation
NGA = Nearby Galaxy Atlas observation
comp? = above and to the right of the loci shown for single stars
at Teff∼7000K
hot = near the hot end of the stellar locus
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 02-Jan-2012