CSS1603+19: a low-mass polar near the cataclysmic variable period minimum
arXiv:2211.14945 · doi:10.1093/mnras/stad1156
Abstract
CSS1603+19 is a cataclysmic variable (CV) with an orbital period of 81.96 min, near the minimal period of cataclysmic variables. It is unusual in having a strong mid-infrared excess inconsistent with thermal emission from a brown dwarf companion. Here we present time-resolved multi-wavelength observations of this system. WISE photometry indicates that the mid-infrared excess displays a one-magnitude eclipsing-like variability during the orbit. We obtained near-infrared and optical spectroscopy using Gemini, MDM and APO telescopes. Near-infrared spectra show possible cyclotron features indicating that the white dwarf has a magnetic field of about 5MG. Optical and near-infrared spectra display double-peaked emission lines, with both components showing strong radial velocity variations during the orbital period and with the broad component leading the narrow component stably by about 0.2 of the orbital phase. We construct a physical model informed by existing observations of the system and determine that one component likely originates from the accretion column onto the magnetized white dwarf in synchronous rotation with the orbital motion and the other from the Roche overflow point. This allows us to constrain the masses of the binary components to be for the white dwarf accretor and for the donor. We classify the system as an AM Herculis star, or a polar. It has likely completed its stint on the period gap, but has not yet gone through the period bounce.
References in corpus (26)
- The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit Performance
- The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
- The Gaia mission
- The Zwicky Transient Facility: Data Processing, Products, and Archive
- Preliminary Results from NEOWISE: An Enhancement to the Wide-field Infrared Survey Explorer for Solar System Science
- Catalogue of cataclysmic binaries, low-mass X-ray binaries and related objects (Seventh edition)
- The Evolution of Cataclysmic Variables as Revealed by their Donor Stars
- Spectroscopic Analysis of DA White Dwarfs: Stark Broadening of Hydrogen Lines Including Non-Ideal Effects
- The Donor Stars of Cataclysmic Variables
- The Zwicky Transient Facility: Observing System
- SDSS unveils a population of intrinsically faint cataclysmic variables at the minimum orbital period
- Brown Dwarfs and the Cataclysmic Variable Period Minimum
- Evolution of Cataclysmic Variables and Related Binaries Containing a White-Dwarf
- Excess mid-IR emission in Cataclysmic Variables
- Lifetime of short-period binaries measured from their Galactic kinematics
- Cyclotron modeling phase-resolved infrared spectroscopy of polars I: EF Eridani
- Spectroscopy and Photometry of Cataclysmic Variable Candidates from the Catalina Real Time Survey
- New Young Brown Dwarfs in the Orion Molecular Cloud 2/3 Region
- Detection of a Variable Infrared Excess Around SDSS 121209.31+013627.7
- Herschel Observations of Cataclysmic Variables
- Internal Structure and Apsidal Motions of Polytropic Stars in Close Binaries
- Variability, periodicity and contact binaries in WISE
- Exploratory Spectroscopy of Magnetic Cataclysmic Variables Candidates and Other Variable Objects II
- Cyclotron Modeling Phase-Resolved Infrared Spectroscopy of Polars III: AM Herculis and ST Leo Minoris
- CRTS J035010.7+323230, a new eclipsing polar in the cataclysmic variable period gap
- The Sonora Brown Dwarf Atmosphere and Evolution Models I. Model Description and Application to Cloudless Atmospheres in Rainout Chemical Equilibrium