Related papers: Stochastic acceleration in Extreme TeV BL Lacs thr…
An irreversible Markov-chain Monte Carlo (MCMC) algorithm with skew detailed balance conditions originally proposed by Turitsyn et al. is extended to general discrete systems on the basis of the Metropolis-Hastings scheme. To evaluate the…
The broadband spectrum from the 2013 December 20 $\gamma$-ray flare from 3C~279 is analyzed with our previously-developed one-zone blazar jet model. We are able to reproduce two SEDs, a quiescent and flaring state, the latter of which had…
Shocks are promising sites of particle acceleration in extragalactic jets. In electron-ion shocks, electrons can be heated up to large Lorentz factors, making them an attractive scenario to explain the high minimum electron Lorentz factors…
We present a general framework for accelerating a large class of widely used Markov chain Monte Carlo (MCMC) algorithms. Our approach exploits fast, iterative approximations to the target density to speculatively evaluate many potential…
The extreme TeV blazar 1ES 0229+200 is a high-frequency-peaked BL Lacertae object. It has not shown intraday variability in extensive optical and X-ray observations. Nor has it shown any significant variability on any measurable timescale…
The MAGIC telescopes observed S2 0109+22 in 2015 July during its flaring activity in high energy gamma rays observed by Fermi-LAT. We analyse the MAGIC data to characterise the very high energy (VHE) gamma-ray emission of S2 0109+22, which…
We present a study on using Markov Chain Monte Carlo (MCMC) techniques to explore the high-dimensional and multi-modal phase space of scattering events at high-energy particle colliders. To this end, we combine the BAT.jl package that…
Precise spectra of 3C 279 in the 0.5-70 keV range, obtained during two epochs of \emph{Swift} and \emph{NuSTAR} observations, are analyzed using a near-equipartition model. We apply a one-zone leptonic model with a three-parameter…
We develop a modular approach to Markov chain Monte Carlo (MCMC) sampling for unnormalized target densities. In this approach, Markov chains are constructed in parallel, each constrained to a subset of the target space. The Monte Carlo…
In this paper we present a fully selfconsistent SSC model with particle acceleration due to shock and stochastic acceleration (Fermi-I and Fermi-II-Processes respectively) to model the quiescent spectral energy distribution (SED) observed…
Evidence for very hard, intrinsic $\gamma$-ray source spectra, as inferred after correction for absorption in the extragalactic background light (EBL), has interesting implications for the acceleration and radiation mechanisms acting in…
M87 is the first extragalactic source detected at the TeV that is not a blazar. To account for the recent observations of M87 made by the High Energy Stereoscopic System (H.E.S.S.) telescope array, we developed a new multi-blob synchrotron…
Many of the extragalactic sources detected in $\gamma$ rays at TeV energies are BL Lac objects. In particular, they belong to the subclass of ``high frequency peaked BL Lacs" (HBLs), as their spectral energy distributions exhibit a first…
Restricted Boltzmann Machines are simple and powerful generative models that can encode any complex dataset. Despite all their advantages, in practice the trainings are often unstable and it is difficult to assess their quality because the…
Blazar spectral energy distributions (SEDs) are double peaked and follow a self-similar sequence in luminosity. The so-called "blue" blazars, whose first SED component peaks at X-ray energies, are TeV sources, although with a relatively…
We consider particle acceleration to high energy via diffusive shock acceleration in a simple, self-consistent shock in jet model for blazars. Electrons are assumed to be accelerated at a shock front in relativistic jets and radiate…
TeV emission from BL Lacertae (BL) objects is commonly modeled as Synchrotron-Self Compton (SSC) radiation from relativistically moving homogeneous plasma blobs. In the context of these models, the blob Lorentz factors needed to reproduce…
Very high energy (~ TeV) $\gamma$-rays from blazars are attenuated by photons from the extragalactic background light (EBL). Observations of blazars can therefore provide an ideal opportunity for determining the EBL intensity if their…
Fermi-LAT analyses show that the gamma-ray photon spectral indices Gamma_gamma of a large sample of blazars correlate with the vFv peak synchrotron frequency v_s according to the relation Gamma_gamma = d - k log v_s. The same function, with…
1ES1101-232 is a bright BL Lac of the High frequency peak class. We present here the results of two BeppoSAX observations in which the source has shown a variation of about 30% in flux with a corresponding spectral variability. We interpret…