Magnetic cataclysmic variables (CVs) versus non-magnetic CVs

A longstanding problem in the interpretation of the X-ray and extreme ultraviolet emission from strongly magnetic cataclysmic variables can be addressed definitively with high resolution EUV spectroscopy. A detailed photospheric spectrum of the accretion-heated polar cap of the white dwarf is sensitive in principle to the temperature structure of the atmosphere. This may allow us to determine where and how the bulk of the accretion energy is thermalized. The EUVE data on AM Herculis and EF Eridani are presented and discussed in this context.

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Accretion Flows in Magnetic Cataclysmic Variables

International Astronomical Union Colloquium ◽

10.1017/s0252921100152224 ◽

2004 ◽

Vol 194 ◽

pp. 138-139

Author(s):

A. J. Norton ◽

R. V. Somerscales ◽

T. L. Parker ◽

G. A. Wynn ◽

R. G. West

Keyword(s):

Cataclysmic Variables ◽

Outer Edge ◽

Roche Lobe ◽

Accretion Flows ◽

Magnetic Cataclysmic Variables

AbstractWe present the results of simulations that explore the variety of accretion flows possible in magnetic cataclysmic variables (mCVs). Our simulations evolve to equilibrium periods spanning 0.01 < Рspin/Рorb < 0.6 and the resulting flows vary from disc-fed systems at Рspin/Рorb ~ 0.01 - 0.1, to stream fed systems at Рspin/Рorb ~ 0.1 - 0.5 and systems fed from a ring at the outer edge of the white dwarf's Roche lobe at Рspin/Рorb ~ 0.6.

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The Characteristics of Magnetic CVs in the Period Gap

International Astronomical Union Colloquium ◽

10.1017/s0252921100001792 ◽

2004 ◽

Vol 190 ◽

pp. 15-21 ◽

Cited By ~ 1

Author(s):

Gaghik Tovmassian ◽

Sergey Zharikov ◽

Ronald Mennickent ◽

Jochen Greiner

Keyword(s):

Mass Transfer ◽

Orbital Period ◽

Accretion Rate ◽

Cataclysmic Variables ◽

Magnetic Systems ◽

Transfer Rates ◽

Significant Difference ◽

Magnetic Cataclysmic Variables

AbstractWe have observed several magnetic cataclysmic variables located in the range between 2 and 3 hours, known as the period gap. This work was prompted by the recent discovery of RXJ1554.2+2721. It has 2.54 hours orbital period and shows almost pure cyclotron continuum in a low luminosity state, similar to HS1023+3900, HS0922+1333 and RBS206. These are low accretion rate polars (LARPs) known to have mass transfer rates of order of a few 10-13M⊙/year. The aim of the study was to find out, if magnetic systems filling the period gap are in any way different from their counterparts outside that range of periods. The only significant difference we encounter is a much higher number of asynchronous magnetic systems towards longer periods than below the gap.

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On the Classification of Magnetic Cataclysmic Variables

International Astronomical Union Colloquium ◽

10.1017/s025292110015239x ◽

2004 ◽

Vol 194 ◽

pp. 180-181

Author(s):

Paul A. Mason

Keyword(s):

Classification Scheme ◽

Cataclysmic Variables ◽

Intermediate Polars ◽

Orbital Periods ◽

Magnetic Cataclysmic Variables

AbstractThe classification scheme for Magnetic Cataclysmic Variables (MCVs) is addressed. When only ten or twenty MCVs had been discovered their classification was simple and based on direct observational properties. Now that the number of MCVs exceeds one hundred, the method of classification needs updating. One important consideration is the possibility that binaries might physically change their classification. For example will intermediate polars become polars as they evolve to shorter orbital periods? Or does a polar become an intermediate polar when synchronism is broken due to a nova?

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