White Dwarf Masses in Magnetic CVs : Multi - temperatureFits to

نویسندگان

  • Mark Cropper
  • Gavin Ramsay
  • Kinwah Wu
چکیده

One method of obtaining the mass of the white dwarf in magnetic CVs is through their hard X-ray spectra. However, previous mass estimates using this method give lower limits because the temperature of the plasma in the post-shock region (where the hard X-rays are emitted) is lower than the temperature of the shock itself. In AM Her systems, the additional cooling of the post-shock plasma by cyclotron emission will further lower the derived mass. Here we present estimates of the masses of the white dwarf in 13 mCVs derived using Ginga data and a model in which X-rays are emitted from a multi-temperature emission region with the appropriate temperature and density proole. We include in the model reeection from the surface of the white dwarf and a partially ionised absorber. We are able to achieve good ts to the data. We compare the derived masses with previous estimates and the masses for larger samples of isolated white dwarfs and those in CVs.

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تاریخ انتشار 1997