Related papers: Recent results on intermediate polars
Models of X-ray production in black-hole sources are reviewed and compared with recent observations. Possible diagnostics of the hot-disk and disk-corona models are discussed in the light of spectral and temporal data. A new model of a…
Three classical modes of accretion are briefly discussed: wind-fed, spherical, and disk. The three modes are illustrated with the mass transfer onto black holes in high-mass X-ray binaries. Then a new regime of mini-disk accretion is…
We present the results of qualitative consideration of possible changes occurring during the transition from the hot accretion disc to the cool one. We argue the possible existence of one more type of spiral density waves in the inner part…
Accreting X-ray pulsars are among the best observed objects of X-ray astronomy with a rich data set of observational phenomena in the spectral and timing domain. While the general picture for these sources is well established, the detailed…
We are reviewing the power of Doppler tomography for detailed investigations of polars (magnetic cataclysmic binaries without accretion disk). Using high-resolution spectroscopy in combination with tomography as analytic tool, the structure…
The paper investigates the influence of accretion heating and turbulent heat conduction on the equilibrium of protoplanetary disks, extending the 2D axis-symmetric passive disk model of Flock (Flock et al. 2016, ApJ 827, 144). The model…
A new numerical algorithm for calculating isothermal wind accretion flows has been developed and is applied here to the analysis of the hydrodynamics of two-dimensional plane symmetric accretion flows in wind-fed sources. Polar coordinates…
I review recent advances in our understanding of accretion disks in transient systems - the dwarf novae and the soft X-ray transients. The primary theme will be the ongoing development of theory in response to the observations. The…
We have developed a 3D computer model of polars which includes the accretion stream, the accretion column, the secondary star, and the white dwarf. Each component is represented by a fine grid of surface elements. With brightness values…
The accretion of material from disks onto weakly magnetized objects invariably involves its traversal through a material surface, known as the boundary layer (BL). Our prior studies have revealed two distinct global wave modes for…
A personal selection of noteworthy X-ray results on CVs are presented, with emphasis on XMM-Newton and Chandra observations. Progressing roughly from broad-band view to narrow-band, high spectral resolution studies, I summarize: the energy…
A solid theoretical understanding of how inflowing, accreting plasma around black holes and other compact objects gives rise to outflowing winds and jets is still lacking, despite decades of observations. The fact that similar processes and…
We present optical photometry of six intermediate polars that exhibit transitions to a low-flux state. For four of these systems, DW Cnc, V515 And, V1223 Sgr and RX J2133.7+5107, we are able to perform timing analysis in and out of the low…
In the EXOSAT and ROSAT eras a significant number of polars were found to show a soft/hard X-ray ratio much greater than that expected from the standard accretion shock model. This was known as the `soft X-ray excess'. We have made an…
The long white-dwarf spin periods in the magnetic cataclysmic variables EX Hya and V1025 Cen imply that if the systems possess accretion discs then they cannot be in equilibrium. It has been suggested that instead they are discless…
This paper reviews current theoretical work on the various stages of accretion in protostars, and the relationship of these ideal stages to the spectral classes of observed protostellar systems. I discuss scaling relationships that have…
We show results of global 3D MHD simulations of accretion onto stars with superposition of the dipole and octupole fields, where we vary the ratio between components. Simulations show that if octupolar field strongly dominates at the…
I review our current theoretical understanding of the different possible rotating modes of accretion onto a black hole. I discuss both thick adiabatic flows and radiatively efficient thin disc solutions. I present a new self-consistent…
Aims: We aim to study the temporal and spectral behaviour of the eclipsing polar CSS081231:071126+440405 from the infrared to the X-ray regime. Methods: We obtained phase-resolved XMM-Newton X-ray observations on two occasions in 2012 and…
Using X-ray observations from the NuSTAR and Swift satellites, we present temporal and spectral properties of an intermediate polar (IP) IGR J16547-1916. A persistent X-ray period at ~ 546 s confirming the optical spin period obtained from…