J/MNRAS/466/163 Candidate Halpha sources in GBS (Wevers+, 2017)
Candidate Halpha emission and absorption line sources in the
Galactic Bulge Survey.
Wevers T., Jonker P.G., Nelemans G., Torres M.A.P., Groot P.J., Steeghs D.,
Maccarone T.J., Hynes R.I., Heinke C., Britt C.
<Mon. Not. R. Astron. Soc. 466, 163-173 (2017)>
=2017MNRAS.466..163W 2017MNRAS.466..163W (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Stars, emission ; Photometry, SDSS ; Photometry, H-alpha
Keywords: Galaxy: bulge - stars: emission line - cataclysmic variables -
binaries: symbiotic - white dwarfs - galaxies: active
Abstract:
We present a catalogue of candidate Halpha emission and absorption
line sources and blue objects in the Galactic Bulge Survey (GBS)
region. We use a point source catalogue of the GBS fields (two strips
of (lxb)=(6°x1°) centred at b=1.5° above and below the
Galactic centre), covering the magnitude range 16≥r'≥22.5. We
utilize (r'-i', r'-Halpha) colour-colour diagrams to select Halpha
emission and absorption line candidates, and also identify blue
objects (compared to field stars) using the r'-i' colour index.
We identify 1337 Halpha emission line candidates and 336 Halpha
absorption line candidates. These catalogues likely contain a plethora
of sources, ranging from active (binary) stars, early-type emission
line objects, cataclysmic variables (CVs) and low-mass X-ray binaries
(LMXBs) to background active galactic nuclei (AGN). The 389 blue
objects we identify are likely systems containing a compact object,
such as CVs, planetary nebulae and LMXBs. Hot subluminous dwarfs
(sdO/B stars) are also expected to be found as blue outliers.
Crossmatching our outliers with the GBS X-ray catalogue yields sixteen
sources, including seven (magnetic) CVs and one qLMXB candidate among
the emission line candidates, and one background AGN for the
absorption line candidates. One of the blue outliers is a high state
AM CVn system. Spectroscopic observations combined with the
multi-wavelength coverage of this area, including X-ray, ultraviolet
and (time-resolved) optical and infrared observations, can be used to
further constrain the nature of individual sources.
Description:
We use optical photometry in three filters (r', i' and Halpha to
create (r'-i', r'-Halpha) colour-colour diagrams of point sources in
the Galactic Bulge Survey Fields (Jonker et al., 2011, Cat.
J/ApJS/194/18; 2014, Cat. J/ApJS/210/18; Wevers et al. 2016, Cat.
J/MNRAS/458/4530).
We identify 1337 emission line candidates, 336 absorption line
candidates, and 389 blue outliers in the catalogue. These samples
likely contain a plethora of sources, ranging from chromospherically
active stars, subluminous hot dwarfs, white dwarfs, CVs, planetary
nebulae, LMXBs and variable stars to background AGN.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
absorber.dat 73 336 Absorption line sources
bluesrc.dat 73 389 Blue sources
emitters.dat 73 1337 Emission line sources
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See also:
J/ApJS/194/18 : Galactic Bulge Survey: X-ray observations (Jonker+, 2011)
J/ApJS/210/18 : X-ray survey of the Galactic Bulge (CXOGBS) (Jonker+, 2014)
J/MNRAS/458/4530 : Chandra Galactic Bulge Survey (Wevers+, 2016)
Byte-by-byte Description of file: absorber.dat bluesrc.dat emitters.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID Object number of the field on which the source
was detected (1)
6 I1 --- CCD [1/8] CCD number (i.e. detector) on which
the source was detected (2)
8- 17 F10.6 deg RAdeg Right ascension of the source (J2000)
19- 28 F10.6 deg DEdeg Declination of the source (J2000)
30- 34 F5.2 mag r'mag r'-band magnitude of the source in
Vega magnitudes
36- 39 F4.2 mag e_r'mag Measurement error of the r-band magnitude
41- 45 F5.2 mag i'mag i'-band magnitude of the source in
Vega magnitudes
47- 50 F4.2 mag e_i'mag Measurement error of the i-band magnitude
52- 56 F5.2 mag Hamag Halpha-band magnitude of the source in
Vega magnitudes
58- 61 F4.2 mag e_Hamag Measurement error of the Halpha-band magnitude
63- 67 F5.2 mag r'-i' r'-i' colour index of the source
(difference of r'mag and i'mag)
69- 73 F5.2 mag r'-Ha r'-Halpha colour index of the source
(difference of r'mag and Hamag)
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Note (1): can be used to trace back the image on which the source was found.
Example: value 53 refers to npobj053catmercat.fits in the
catalogue J/MNRAS/458/4530
Example: value 118 refers to npobj118catmercat.fits in the
catalogue J/MNRAS/458/4530
Note (2): can be used to trace back the image on which the source was found.
Values range from 1-8, since there are 8 detectors in the instrument used.
Example: value 3 refers to CCD 3 of the corresponding field of Column 1 in
the fits catalogue files of catalogue J/MNRAS/458/4530.
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Acknowledgements:
Thomas Wevers, t.wevers(at)astro.ru.nl
(End) Patricia Vannier [CDS] 05-Jan-2017