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Nikita Rawat
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Magnetic Cataclysmic Variables (MCVs) are a class of semi-detached binary star systems that consist of a white dwarf (WD) and a companion star, typically a Roche-lobe filling late-type main sequence star. The strong magnetic field associated with the WD distinguishes MCVs from other cataclysmic variables. It plays a crucial role in governing the accretion process in these binaries and also decides two distinct classes of MCVs: polars and intermediate polars (IPs). In polars, the magnetic field of the WD is strong enough (typically, in a range of 10-100 MG) to lock the whole system into synchronous (or almost synchronous) rotation. While in the case of IPs, the magnetic field of the WD is weaker (typically, 1-10 MG), and the majority of IPs have spin period of the WD, roughly one-tenth of the orbital period of the binary system. MCVs exhibit a wide range of timing (periodic and quasi-periodic) and spectral properties, more commonly in optical and X-ray wavelengths, that aid in characterizing and understanding the accretion physics of these systems. In fact, numerous CVs have been accidentally found in a number of X-ray and optical studies. Although there are more than a thousand known CVs, only 130 polars and 71 IPs have been confirmed as of now. We can learn a lot about the physics of accretion and the relationship between the accretion flow and magnetic field from the X-ray and optical studies of MCVs. Among the MCVs, the appropriate classification of new sources is also essential to understand these systems thoroughly in terms of their accretion geometry. The evolution of MCVs, particularly the relationship between IPs and polars, is a significant aspect of CV research that can be addressed through enhanced member statistics. Further, the variable nature of accretion flow is one of the basic characteristics of an IP and has been observed in only a few IPs. In light of this, we have studied a sample of 9 objects in various evolutionary phases with spin-to-orbital period ratios ranging from 0.1 to 1.0 to understand and examine the different features they display

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Nikita Rawat is a Senior Research Fellow in the astronomy division at ARIES. This is her pre-thesis submission talk. 

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ARIES seminar/colloquium committee
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