MAGNETIC CATACLYSMIC VARIABLES (CVs)
What is a Magnetic CV? Magnetic cataclysmic variables (CVs) are binary star systems that contain a white dwarf with a magnetic field that is strong enough to control the accretion flow from a late type Roche-lobe secondary. Late type secondaries are cooler stars with spectral types such as K and M.
This site contains the catalogue of the known Magnetic CVs.
Each magnetic cataclysmic variable binary (mCV) is categorized as either a polar or an intermediate polar (IP). The polars are further divided the disjoint sub-classes of synchronous polars (P), asynchronous polars (AP), and the low luminosity/pre-polars (LP) also known as Low Accretion-Rate Polars (LARPs).
The intermediate polars are divided into the normal IPs (IP), the transitional IPs (TIP), and the low-luminosity IPs (LIP). Several polars and intermediate polars have been the site of a novae eruption, designated by N and/or dwarf novae eruptions, designated by DN in the catalog.
The disjoint sets, as defined for this catalog, are described as follows:
This is an observational database with links and detailed information of known Magnetic CVs.
P = Synchronous Polars
These polars have a white dwarf spin period that is equal to the binary orbital period. This is because the white dwarf's magnetic field is strong enough to synchronous the white dwarf's rotation to the binary orbit.
AP = Asynchronous Polars
These polars have a white dwarf spin period that are up to a few percent different (longer or shorter) than the binary orbital period. These are probable only temporary APs as they all are moving towards synchronization.
LP = Low Accretion Rate Polars/ Pre-Polars
These polars show evidence for strong magnetic fields but very low level accretion and some may be evolving to become polars for the first time. The latter are called pre-polars.
IP = Intermediate Polars
The white dwarf magnetic field is not strong enough to disrupt the accretion disk in nearly all of the intermediate polars. The white dwarf spin period often spins much faster than the binary orbital period. This is due to mass accretion from the disk along the magnetic field lines that results in the spin-up of the white dwarf.
LIP = Low Luminosity Intermediate Polars
These IPs accrete at a much lower rates than the normal IPs.
TIP = Transitional Intermediate Polars
These IPs are undergoing a transition from an IP to a polar. They have white dwarf rotation rates that are not too different than their orbital periods. They are the only IPs to have magnetic fields similar to polars, as measured by polarization and some TIPs, accrete by a stream rather than a disk or combination of a disk and stream.
224 results found.