A5086643466- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Solar and Space Plasma Dynamics
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Ionosphere and magnetosphere dynamics
- Dark Matter and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Stellar, planetary, and galactic studies
- Neutrino Physics Research
- Cosmology and Gravitation Theories
- Radio Astronomy Observations and Technology
- Astronomy and Astrophysical Research
- Geophysics and Gravity Measurements
- Photonic and Optical Devices
- Geomagnetism and Paleomagnetism Studies
- Semiconductor Lasers and Optical Devices
- Particle Detector Development and Performance
- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Advanced Fiber Optic Sensors
- Earthquake Detection and Analysis
- Dust and Plasma Wave Phenomena
Ioffe Institute
2015-2024
International Space Science Institute
2014-2023
Physical and Technical Institute
2023
Peter the Great St. Petersburg Polytechnic University
2012-2021
Laboratoire Univers et Particules de Montpellier
2018
Centre National de la Recherche Scientifique
2011-2018
Université de Montpellier
2018
North Carolina State University
2017-2018
Physico-Technical Institute
1996-2018
Institut d'Astrophysique de Paris
2011-2017
The first $\ensuremath{\gamma}$-ray line originating from outside the Solar System that was ever detected is 511 keV emission positron annihilation in Galaxy. Despite 30 years of intense theoretical and observational investigation, main sources positrons have not been identified up to now. Observations 1990s with OSSE/CGRO (Oriented Scintillation Spectrometer Experiment on GRO satellite/Compton Gamma Ray Observatory) showed strongly concentrated toward Galactic bulge. In 2000s, spectrometer...
Collisionless shocks, that is shocks mediated by electromagnetic processes, are customary in space physics and astrophysics. They to be found a great variety of objects environments: magnetospheric heliospheric supernova remnants, pulsar winds their nebulæ, active galactic nuclei, gamma-ray bursts clusters galaxies shock waves. microphysics enters at different stages formation, dynamics particle energization and/or acceleration. It turns out the phenomenon multi-scale non-linear problem time...
XIPE, the X-ray Imaging Polarimetry Explorer, is a mission dedicated to Astronomy. At time of writing XIPE in competitive phase A as fourth medium size ESA (M4). It promises reopen polarimetry window high energy Astrophysics after more than 4 decades thanks detector that efficiently exploits photoelectric effect and optics with large effective area. uniqueness time-spectrally-spatially- resolved breakthrough astrophysics fundamental physics. Indeed payload consists three Gas Pixel Detectors...
Observations indicate that most massive stars in the Galaxy appear groups, called OB associations, where their strong wind activity generates large structures known as superbubbles, inside which subsequent supernovae (SNe) explode, with a tight space and time correlation. We investigate four main questions: 1) does clustering of SN explosions influence particle acceleration process usually associated SNe, induce collective effects would not manifest around isolated supernova remnants?; 2) it...
In evolved supernova remnants (SNRs) interacting with molecular clouds, a highly inhomogeneous structure consisting of forward shock moderate Mach number, cooling layer, dense radiative shell, and an interior region filled hot tenuous plasma is expected. We present model nonthermal electron injection, acceleration, propagation in that environment find these SNRs are efficient accelerators sources hard X-ray γ-ray emission. A velocity vs ≳ 100 km s-1 ionized precursor propagating into the...
We introduce a Monte Carlo model of nonlinear diffusive shock acceleration that allows for the generation large-amplitude magnetic turbulence, i.e., ΔB ≫ B0, where B0 is ambient field. The first to include strong wave generation, efficient particle relativistic energies in nonrelativistic shocks, and thermal injection an internally self-consistent manner. find upstream field can be amplified by large factors show this amplification depends strongly on Alfvén Mach number. also that, model,...
We report on six new Chandra observations of the Geminga pulsar wind nebula (PWN). The PWN consists three distinct elongated structures - two $\approx 0.2 d_{250}$ pc long lateral tails and a segmented axial tail 0.05 length, where $d_{250}=d/(250 {\rm pc})$. photon indices power law spectra tails, $\Gamma \approx 1$, are significantly harder than those ($\Gamma 1.5$) 1.6$). There is no significant diffuse X-ray emission between -- ratio surface brightness south this sky area at least 12....
Generation of non-thermal particles in an OB association is studied. A model cosmic-ray acceleration proposed where the interaction charged with ensemble shocks and large-scale plasma motions inside bubble included. The appears to be very efficient especially after explosions a few supernovae association. time order 105 yr. Some tens per cent kinetic energy can converted acceleration.
This review presents methods available for calculating transport coefficients impurity particles in plasmas with strong long-wave MHD-type velocity and magnetic-field fluctuations, random ensembles of shock fronts. The renormalization the mean-field equation turbulent dynamo theory is also considered. Particular attention devoted to method developed by authors which renormalized are calculated from a nonlinear transcendental (or set such equations) expressed form explicit functions pair...
We report here X-ray imaging spectroscopy observations of the northeastern shell supernova remnant RCW 86 with Chandra and XMM-Newton. Along this part dominant radiation mechanism changes from thermal to synchrotron emission. argue that both presence width emitting region suggest a locally higher shock velocity V_s = 2700 km/s magnetic field B 24+/-5 microGauss. Moreover, we also show simple power law cosmic ray electron spectrum an exponential cut-off cannot explain broad band Instead...
Non-thermal components are key ingredients for understanding clusters of galaxies. In the hierarchical model structure formation, shocks and large-scale turbulence unavoidable in cluster formation processes. Understanding amplification evolution magnetic field galaxy is necessary modelling both heat transport dissipative processes hot intra-cluster plasma. The acceleration, interactions non-thermal energetic particles essential observed emissions. Therefore, inclusion will be mandatory...
We present a spherically symmetric, core-collapse model of SNR RX J1713.7−3946 that includes hydrodynamic simulation the remnant evolution coupled to efficient production cosmic rays (CRs) by nonlinear diffusive shock acceleration. High-energy CRs escape from forward (FS) are propagated in surrounding dense material simulates either swept-up, pre-supernova shell or nearby molecular cloud. The continuum emission trapped and escaping CRs, along with thermal X-ray shocked heated interstellar...
Astrophysical shocks are often collisionless shocks. An open question about is whether electrons and ions each establish their own post-shock temperature, or they quickly equilibrate in the shock region. Here we provide simple relations for minimal amount of equilibration to expect. The basic assumption that enthalpy-flux conserved separately, but all particle species should undergo same density jump across shock. This results an analytic treatment electron-ion agrees with observations...