TY - JOUR
T1 - CXOGBS J174954.5-294335
T2 - A new deeply eclipsing intermediate polar
AU - Johnson, Christopher B.
AU - Torres, M. A.P.
AU - Hynes, R. I.
AU - Jonker, P. G.
AU - Heinke, C.
AU - Maccarone, T.
AU - Britt, C. T.
AU - Steeghs, D.
AU - Wevers, T.
AU - Wu, J.
N1 - Publisher Copyright:
© 2016 The Authors.
PY - 2017/4/1
Y1 - 2017/4/1
N2 - We present the results of a photometric and spectroscopic analysis of the Galactic Bulge Survey X-ray source CXOGBS J174954.5-294335 (hereafter, referred to as CX19). CX19 is a long period, eclipsing intermediate polar-type cataclysmic variable with broad, singlepeaked Balmer and Paschen emission lines along with He II λ4686 and Bowen blend emission features. With coverage of one full and two partial eclipses and archival photometry, we determine the ephemeris for CX19 to beHJD(eclipse)=2455691.8581(5)+0.358704(2)×N. We also recovered the white dwarf spin period of Pspin = 503.32(3) s that gives a Pspin/Porb = 0.016(6), comparable to several confirmed, long-period intermediate polars. CX19 also shows a clear X-ray eclipse in the 0.3-8.0 keV range observed with Chandra. Two optical outbursts were observed lasting between 6 and 8 h (lower limits) reaching ~1.3 mag in amplitude. The outbursts, both in duration and magnitude, the accretion disc-dominated spectra and hard X-ray emission are reminiscent of the intermediate polar V1223 Sgr sharing many of the same characteristics. If we assume amain-sequence companion, we estimate the donor to be an early G-type star and find a minimum distance of d ≈ 2.1 kpc and a 0.5-10.0 keV X-ray luminosity upper limit of 2.0 × 1033 erg s-1. Such an X-ray luminosity is consistent with a white dwarf accretor in a magnetic cataclysmic variable system. To date, CX19 is only the second deeply eclipsing intermediate polar with X-ray eclipses and the first that is optically accessible.
AB - We present the results of a photometric and spectroscopic analysis of the Galactic Bulge Survey X-ray source CXOGBS J174954.5-294335 (hereafter, referred to as CX19). CX19 is a long period, eclipsing intermediate polar-type cataclysmic variable with broad, singlepeaked Balmer and Paschen emission lines along with He II λ4686 and Bowen blend emission features. With coverage of one full and two partial eclipses and archival photometry, we determine the ephemeris for CX19 to beHJD(eclipse)=2455691.8581(5)+0.358704(2)×N. We also recovered the white dwarf spin period of Pspin = 503.32(3) s that gives a Pspin/Porb = 0.016(6), comparable to several confirmed, long-period intermediate polars. CX19 also shows a clear X-ray eclipse in the 0.3-8.0 keV range observed with Chandra. Two optical outbursts were observed lasting between 6 and 8 h (lower limits) reaching ~1.3 mag in amplitude. The outbursts, both in duration and magnitude, the accretion disc-dominated spectra and hard X-ray emission are reminiscent of the intermediate polar V1223 Sgr sharing many of the same characteristics. If we assume amain-sequence companion, we estimate the donor to be an early G-type star and find a minimum distance of d ≈ 2.1 kpc and a 0.5-10.0 keV X-ray luminosity upper limit of 2.0 × 1033 erg s-1. Such an X-ray luminosity is consistent with a white dwarf accretor in a magnetic cataclysmic variable system. To date, CX19 is only the second deeply eclipsing intermediate polar with X-ray eclipses and the first that is optically accessible.
KW - Binaries: eclipsing
KW - Cataclysmic variables
KW - Galaxy: bulge
KW - Novae
KW - Stars: magnetic field
KW - White dwarfs
KW - X-rays: binaries
UR - http://www.scopus.com/inward/record.url?scp=85018314203&partnerID=8YFLogxK
U2 - 10.1093/mnras/stw3063
DO - 10.1093/mnras/stw3063
M3 - Article
AN - SCOPUS:85018314203
SN - 0035-8711
VL - 466
SP - 129
EP - 137
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 1
ER -