Direct detection of SDSS J0926+3624 orbital expansion with ARCONS

作者：Szypryt P^*; Duggan G E; Mazin B A; Meeker S R; Strader M J; van Eyken J C; Marsden D; O'Brien K; Walter A B; Ulbricht G; Prince T A; Stoughton C; Bumble B

来源：Monthly Notices of the Royal Astronomical Society, 2014, 439(3): 2765-2770.

DOI：10.1093/mnras/stu137

• binaries: close
• binaries: eclipsing
• stars: individual: SDSS J0926+3624
• cataclysmic variables
• white dwarfs

AM Canum Venaticorum (AM CVn) stars belong to a class of ultracompact, short-period binaries with spectra dominated largely by helium. SDSS J0926+3624 is of particular interest as it is the first observed eclipsing AM CVn system. We observed SDSS J0926+3624 with the Array Camera for Optical to Near-IR Spectrophotometry (ARCONS) at the Palomar 200 ' telescope. ARCONS uses a relatively new type of energy-resolved photon counters called Microwave Kinetic Inductance Detectors. ARCONS, sensitive to radiation from 350 to 1100 nm, has a time resolution of several microseconds and can measure the energy of a photon to similar to 10 per cent. We present the light curves for these observations and examine changes in orbital period from prior observations. Using a quadratic ephemeris model, we measure a period rate of change P = (3.07 +/- 0.56) x 10(-13). In addition, we use the high timing resolution of ARCONS to examine the system's high-frequency variations and search for possible quasi-periodic oscillations (QPOs). Finally, we use the instrument's spectral resolution to examine the light curves in various wavelength bands. We do not find any high-frequency QPOs or significant spectral variability throughout an eclipse.

• 出版日期2014-4