Related papers: Spectral Analysis of $\chi$ Class Data of GRS 1915…
A modified non-linear time series analysis technique, which computes the correlation dimension $D_2$, is used to analyze the X-ray light curves of the black hole system GRS 1915+105 in all twelve temporal classes. For four of these temporal…
Recent learning-based methods for event-based optical flow estimation utilize cost volumes for pixel matching but suffer from redundant computations and limited scalability to higher resolutions for flow refinement. In this work, we take…
In this chapter, we present a brief and non-exhaustive review of the developments of theoretical models for accretion flows around neutron stars. A somewhat chronological summary of crucial observations and modelling of timing and spectral…
Monitoring with the Ryle Telescope at 15 GHz of the Galactic X-ray transient source GRS 1915+105 has revealed a remarkable range of rapid and extended flares which appear to be related to the X-ray emission as recorded by the RXTE all-sky…
Two fundamental problems in unsupervised learning are efficient inference for latent-variable models and robust density estimation based on large amounts of unlabeled data. Algorithms for the two tasks, such as normalizing flows and…
We present results of X-ray spectral and time-domain variability analyses of 4 faint, "quiescent" blazars from the Swift-BAT 105-month catalog. We use observations from a recent, 5-month long NICER campaign, as well as archival BAT data.…
I study the formation of Comptonization spectra in spherically symmetric, fast moving media in a flat spacetime. I analyze the mathematical character of the moments of the transfer equation in the system-frame and describe a numerical…
We present the first detailed phase-resolved spectral analysis of a joint Chandra High Energy Transmission Grating Spectrometer and Rossi X-ray Timing Explorer observation of the rho variability class in the microquasar GRS 1915+105. The…
We introduce the scalar function $C(v)=\pi(1-v^2/c^2)$ as a conformal factor associated, within the model, with longitudinal Lorentz contraction. Extending $C(v)$ to a one-parameter family $C(v,\tau)$, we construct a variational scalar…
The typical blazar S5 0716$+$714 is very interesting due to its rapid and large amplitude variability and high duty cycle of micro-variability in optical band. We analyze the observations in I, R and V bands obtained with the $1.0m$…
We present the characteristics of the sources found on the averaged scans of the "Cold" experiment 1980--1999 surveys in the right-ascension interval $2^h$< RA <$7^h$. Thereby, a refinement of the parameters of the RC catalog sources (RATAN…
We study several Galactic black hole candidates using long-time RXTE/ASM X-ray data to search for telltale signatures of differences in viscous timescales in the two components used in the Two-Component Advective Flow (TCAF) paradigm. In…
We study self-similarity problem for two classes of flows: (1) special flows over circle rotations and under roof functions with symmetric logarithmic singularities (2) special flows over interval exchange transformations and under roof…
We report the results of 3 observations of GRS 1915+105 during which the source is found to show the X-ray dips/spike sequences (cycles). These observations were performed simultaneously with \integral, RXTE, the Ryle and Nancay radio…
We present the results of a detailed analysis of RXTE observations of class $\omega$ which show an unusual state transition between high-soft and low-soft states in the microquasar GRS 1915+105. Out of about 600 pointed RXTE observations,…
We have analysed 16 observations of class beta of GRS 1915+105 performed with the Rossi X-ray Timing Explorer. We show the time-resolved evolution (every 16 seconds) of the X-ray spectral parameters during these observations. The three…
We present broad band power spectra of variations of SS433 in radio, optical and X-ray spectral bands. We show that at frequencies lower than 1e-5 Hz the source demonstrates the same variability pattern in all these bands. The broad band…
Diffusion models and their variations, such as rectified flows, generate diverse and high-quality images, but they are still hindered by slow iterative sampling caused by the highly curved generative paths they learn. An important cause of…
Turbulence, namely, irregular fluctuations in space and time characterize fluid flows in general and atmospheric flows in particular.The irregular,i.e., nonlinear space-time fluctuations on all scales contribute to the unpredictable nature…
The flux reconstruction (FR) approach offers a flexible framework for describing a range of high-order numerical schemes; including nodal discontinuous Galerkin and spectral difference schemes. This is accomplished through the use of…