TY - JOUR
T1 - Two more candidate AM canum venaticorum (AM CVn) BINARIES from the sloan digital sky survey
AU - Anderson, Scott F.
AU - Becker, Andrew C.
AU - Haggard, Daryl
AU - Prieto, Jose Luis
AU - Knapp, Gillian R.
AU - Sako, Masao
AU - Halford, Kelly E.
AU - Jha, Saurabh
AU - Martin, Blake
AU - Holtzman, Jon
AU - Frieman, Joshua A.
AU - Garnavich, Peter M.
AU - Hayward, Suzanne
AU - Ivezić, Željko
AU - Mukadam, Anjum S.
AU - Sesar, Branimir
AU - Szkody, Paula
AU - Malanushenko, Viktor
AU - Richmond, Michael W.
AU - Schneider, Donald P.
AU - York, Donald G.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2008/6/1
Y1 - 2008/6/1
N2 - AM CVn systems are a select group of ultracompact binaries with the shortest orbital periods of any known binary subclass; mass transfer is likely from a low-mass (partially-)degenerate secondary onto a white dwarf primary, driven by gravitational radiation. In the past few years, the Sloan Digital Sky Survey (SDSS) has provided five new AM CVns. Here we report on two further candidates selected from more recent SDSS data. SDSS J1208+3550 is similar to the earlier SDSS discoveries, recognized as an AM CVn via its distinctive spectrum which is dominated by helium emission. From the expanded SDSS Data Release 6 (DR6) spectroscopic area, we provide an updated surface density estimate for such AM CVns of order 10-3.1-10-2.5 deg -2 for 15 < g < 20.5. In addition, we present another new candidate AM CVn, SDSS J2047+0008, which was discovered in the course of follow-up of SDSS-II supernova candidates. It shows nova-like outbursts in multi-epoch imaging data; in contrast to the other SDSS AM CVn discoveries, its (outburst) spectrum is dominated by helium absorption lines, reminiscent of KL Dra, and 2003aw. The variability selection of SDSS J2047+0008 from the 300 deg2 of SDSS Stripe 82 presages further AM CVn discoveries in future deep, multicolor, and time-domain surveys such as the Large Synoptic Survey Telescope (LSST). The new additions bring the total SDSS yield to seven AM CVns thus far, a substantial contribution to this rare subclass, versus the dozen previously known.
AB - AM CVn systems are a select group of ultracompact binaries with the shortest orbital periods of any known binary subclass; mass transfer is likely from a low-mass (partially-)degenerate secondary onto a white dwarf primary, driven by gravitational radiation. In the past few years, the Sloan Digital Sky Survey (SDSS) has provided five new AM CVns. Here we report on two further candidates selected from more recent SDSS data. SDSS J1208+3550 is similar to the earlier SDSS discoveries, recognized as an AM CVn via its distinctive spectrum which is dominated by helium emission. From the expanded SDSS Data Release 6 (DR6) spectroscopic area, we provide an updated surface density estimate for such AM CVns of order 10-3.1-10-2.5 deg -2 for 15 < g < 20.5. In addition, we present another new candidate AM CVn, SDSS J2047+0008, which was discovered in the course of follow-up of SDSS-II supernova candidates. It shows nova-like outbursts in multi-epoch imaging data; in contrast to the other SDSS AM CVn discoveries, its (outburst) spectrum is dominated by helium absorption lines, reminiscent of KL Dra, and 2003aw. The variability selection of SDSS J2047+0008 from the 300 deg2 of SDSS Stripe 82 presages further AM CVn discoveries in future deep, multicolor, and time-domain surveys such as the Large Synoptic Survey Telescope (LSST). The new additions bring the total SDSS yield to seven AM CVns thus far, a substantial contribution to this rare subclass, versus the dozen previously known.
KW - Binaries: close
KW - Novae, cataclysmic variables
KW - Stars: individual (SDSS J120841.96+355025.2, SDSS J204739.40+000840.3)
KW - White dwarfs
UR - http://www.scopus.com/inward/record.url?scp=50849109224&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=50849109224&partnerID=8YFLogxK
U2 - 10.1088/0004-6256/135/6/2108
DO - 10.1088/0004-6256/135/6/2108
M3 - Article
AN - SCOPUS:50849109224
SN - 0004-6256
VL - 135
SP - 2108
EP - 2113
JO - Astronomical Journal
JF - Astronomical Journal
IS - 6
ER -