2XMMi J225036.9+573154 - a new eclipsing AM Her binary discovered using XMM-Newton

Abstract

We report the discovery of an eclipsing polar, 2XMMi J225036.9+573154, using XMM-Newton. It was discovered by searching the light curves in the 2XMMi catalogue for objects showing X-ray variability. Its X-ray light curve shows a total eclipse of the white dwarf by the secondary star every 174 mins. An extended pre-eclipse absorption dip is observed in soft X-rays at phi=0.8-0.9, with evidence for a further dip in the soft X-ray light curve at phi~0.4. Further, X-rays are seen from all orbital phases (apart from the eclipse) which makes it unusual amongst eclipsing polars. We have identified the optical counterpart, which is faint (r=21), and shows a deep eclipse (>3.5 mag in white light). Its X-ray spectrum does not show a distinct soft X-ray component which is seen in many, but not all, polars. Its optical spectrum shows Halpha in emission for a fraction of the orbital period.

Accepted for publication in MNRAS

References in corpus (14)

• On the Absorption of X-rays in the Interstellar Medium
• The Swift Ultra-Violet/Optical Telescope
• The XMM-Newton Serendipitous Survey. V. The Second XMM-Newton Serendipitous Source Catalogue
• The Distance to the Perseus Spiral Arm in the Milky Way
• The XMM-Newton Serendipitous Survey I. The role of XMM-Newton Survey Science Centre
• Effects of Gravity on the Structure of Postshock Accretion Flows in Magnetic Cataclysmic Variables
• IPHAS and the symbiotic stars. I. Selection method and first discoveries
• The energy balance in polars revisited
• Unravelling the Puzzle of the Eclipsing Polar SDSSJ 015543.40+002807.2 with XMM and Optical Photometry/Spectropolarimetry
• The serendipituous discovery of a short-period eclipsing polar in 2XMMp
• X-Ray Emission and Optical Polarization of V1432 Aquilae: An Asynchronous Polar
• XMM-Newton observations of the eclipsing polar V2301 Oph
• XMM-Newton observation of the long-period polar V1309 Ori: The case for pure blobby accretion
• XMM-Newton and optical follow-up observations of three new polars from the Sloan Digital Sky Survey

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