M. Ostrowski
A5025423639- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Radio Astronomy Observations and Technology
- Solar and Space Plasma Dynamics
- Particle Detector Development and Performance
- Neutrino Physics Research
- Pulsars and Gravitational Waves Research
- Particle Accelerators and Free-Electron Lasers
- Cosmology and Gravitation Theories
- Astronomical Observations and Instrumentation
- Ionosphere and magnetosphere dynamics
- Galaxies: Formation, Evolution, Phenomena
- Particle physics theoretical and experimental studies
- Astronomy and Astrophysical Research
- Radiation Detection and Scintillator Technologies
- Lightning and Electromagnetic Phenomena
- Earthquake Detection and Analysis
- Laser-Plasma Interactions and Diagnostics
- Parallel Computing and Optimization Techniques
- Stellar, planetary, and galactic studies
- Particle accelerators and beam dynamics
- CCD and CMOS Imaging Sensors
- Astro and Planetary Science
Jagiellonian University
2016-2025
University of Oxford
2019-2025
Nuffield Health
2025
Astronomical Observatory
1996-2024
Institut de Recherche sur les Lois Fondamentales de l'Univers
2021-2023
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2021-2023
ETH Zurich
2019-2023
University of Würzburg
2023
Max Planck Institute for Physics
2023
École Polytechnique
2023
We observed the W28 field (for ~40 h) at Very High Energy (VHE) gamma-ray energies (E>0.1 TeV) with H.E.S.S. Cherenkov telescopes. A reanalysis of EGRET E>100 MeV data was also undertaken. Results from NANTEN 4m telescope Galactic plane survey and other CO observations have been used to study molecular clouds. discovered VHE emission (HESSJ1801-233) coincident northeastern boundary W28, a complex sources (HESSJ1800-240A, B C) ~0.5 deg south in disc. The differential photon spectra are well...
Aims.To investigate the very high energy (VHE: >100 GeV) γ-ray emission from high-frequency peaked BL Lac 1ES 0229+200.
Energy spectra of particles accelerated by the first-order Fermi mechanism are investigated at ultrarelativistic shock waves, outside range Lorentz factors considered previously. For particle transport near a numerical method involving small amplitude pitch-angle scattering is applied for flows with $\gamma$ from 3 to 243. large shocks convergence derived energy spectral indices up value $\sigma_\infty \approx 2.2$ observed all turbulence amplitudes and magnetic field configurations....
Context.The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV–100 TeV) provides a direct view parent population ultra-relativistic particles found astrophysical sources. For this reason, VHE are useful for understanding underlying processes non-thermal
Gamma-ray bursts (GRBs), which have been observed up to redshifts z approx 9.5 can be good probes of the early universe and potential testing cosmological models. The analysis by Dainotti GRB Swift afterglow lightcurves with known definite X-ray plateau shows an anti-correlation between rest frame time when ends (the end time) calculated luminosity at that (or approximately duration luminosity). We present here update this correlation a larger data sample 101 GRBs lightcurves. Since some...
Detection of periodicity in the broad-band non-thermal emission blazars has so far been proven to be elusive. However, there are a number scenarios which could lead quasi-periodic variations blazar light curves. For example, orbital or thermal/viscous period accreting matter around central supermassive black holes could, principle, imprinted multi-wavelength small-scale jets, carrying as such crucial information about plasma conditions within jet launching regions. In this paper, we present...
The central region of the Milky Way is one foremost locations to look for dark matter (DM) signatures. We report first results on a search DM particle annihilation signals using new observations from an unprecedented gamma-ray survey Galactic Center (GC) region, ${\it i.e.}$, Inner Galaxy Survey, at very high energies ($\gtrsim$ 100 GeV) performed with H.E.S.S. array five ground-based Cherenkov telescopes. No significant excess found in 2014-2020 dataset and profile likelihood ratio analysis...
Stimulated by recent observations of a radio-to-X-ray synchrotron flare from HST-1, the innermost knot M 87 jet, as well detection very high energy gamma-ray emission 87, we investigated dynamics and multiwavelength HST-1 region. We study thermal pressure hot interstellar medium in argue for presence gaseous condensation its central parts. Interaction jet with such feature is likely to result formation converging reconfinement shock parts jet. show that realistic set outflow parameters,...
K42 is one of the few recent research projects that examining operating system design structure issues in context new whole-system design. open source and was designed from ground up to perform well be scalable, customizable, maintainable. The project begun 1996 by a team at IBM Research. Over last nine years there has been development effort on between six twenty researchers developers across IBM, collaborating universities, national laboratories. supports Linux API ABI, able run unmodified...
<i>Aims.<i/>Our aim is to study the production mechanism for very-high-energy (VHE; >100 GeV) <i>γ<i/>-rays in distant active galactic nuclei (AGN) and use observed VHE spectrum derive limits on Extragalactic Background Light (EBL). We also want determine physical quantities through modeling of object's broad-band spectral energy distribution (SED).<i>Methods.<i/>VHE observations (~25 h live time) BL Lac 1ES 0347-121 (redshift ) were conducted with High Energy Stereoscopic System (HESS)...
We present an analysis of 123 Gamma-ray bursts (GRBs) with known redshifts possessing afterglow plateau phase. reveal that $L_a-T^{*}_a$ correlation between the X-ray luminosity $L_a$ at end phase and duration, $T^*_a$, in GRB rest frame has a power law slope different, within more than 2 $\sigma$, from prompt $L_{f}-T^{*}_{f}$ isotropic pulse peak luminosity, $L_{f}$, $T^{*}_{f}$, time since ejection. Analogously, we show differences phases energy-duration distributions emitted energy being...
Abstract We present the Hylaty geophysical station, a high‐sensitivity and low‐noise facility for extremely low frequency (ELF, 0.03–300 Hz) electromagnetic field measurements, which enables variety of climatological research related to atmospheric, ionospheric, magnetospheric, space weather physics. The first systematic observations ELF fields at Jagiellonian University were undertaken in 1994. At beginning measurements carried out sporadically, during expeditions sparsely populated areas...
Abstract We present the results of our power spectral density analysis for BL Lac object OJ 287, utilizing Fermi -LAT survey at high-energy γ -rays, Swift -XRT in X-rays, several ground-based telescopes and Kepler satellite optical, radio GHz frequencies. The light curves are modeled terms continuous-time autoregressive moving average (CARMA) processes. Owing to inclusion data, we were able construct first time optical variability spectrum a blazar without any gaps across ∼6 dex temporal Our...
Young massive stellar clusters are extreme environments and potentially provide the means for efficient particle acceleration. Indeed, they increasingly considered as being responsible a significant fraction of cosmic rays (CRs) accelerated within Milky Way. Westerlund 1, most known young cluster in our Galaxy is prime candidate studying this hypothesis. While very-high-energy $\gamma$-ray source HESS J1646-458 has been detected vicinity 1 past, its association could not be firmly...
Recent radio and optical large-scale jet observations suggest a two-component morphology, consisting of fast central spine surrounded by boundary layer with velocity shear. We study radiation electrons accelerated at such layers as an option for standard approaches involving internal shocks in jets. The acceleration process the yields natural way electron distribution: power-law continuum bump energy where gains equal losses, followed cutoff. For distributions, we derive observed spectra...
Autonomic computing systems are designed to be self-diagnosing and self-healing, such that they detect performance correctness problems, identify their causes, apply the appropriate remedy. These abilities can improve performance, uptime, security, while simultaneously reducing effort skills required of system administrators. One way support these is by allowing monitoring code, diagnostic function implementations dynamically inserted removed in live systems. This "hot swapping" avoids...
To reveal and understand astrophysical processes responsible for the Gamma Ray Burst (GRB) phenomenon, it is crucial to discover relations between their observational properties. The presented study performed in GRB rest frames uses a sample of 62 long GRBs from our 77 Swift with known redshifts. Following earlier analysis afterglow {\it characteristic luminosity $L^*_a$ -- break time $T^*_a$} correlation \citep{Dainotti2010} we extend correlations prompt emission physical parameters. We...
Gamma-ray bursts (GRBs) observed up to redshifts z>8 are fascinating objects study due their still unexplained relativistic outburst mechanisms and possible use test cosmological models. Our analysis of 77 GRB afterglows with known revealed a physical subsample long GRBs the canonical plateau breaking power-law light curves significant luminosity L*X–break time T*a correlation in rest frame. This forms approximately upper envelope studied distribution. We have also found similar relation for...
Gamma Ray Bursts (GRBs) are the most energetic sources in universe and among farthest known astrophysical sources. These features make them appealing candidates as standard candles for cosmological applications so that studying physical mechanisms origin of emission correlations their observable properties is an interesting task. We consider here luminosity L*X - break time Ta* (hereafter LT) correlation investigate whether there systematics induced by selection effects or redshift dependent...
Blazars are the established sources of an intense and variable non-thermal radiation extending from radio wavelengths up to HE VHE gamma-rays. Understanding spectral evolution blazars in selected frequency ranges, as well multi-frequency correlations various types blazar sources, is a primary importance for constraining physics. Here we present results long-term optical monitoring sample 30 BL Lac type. We study color-magnitude correlation patterns emerging analyzed sample, compare...
The single-mirror small-size telescope (SST-1M) is one of the three proposed designs for telescopes (SSTs) Cherenkov Telescope Array (CTA) project. SST-1M will be equipped with a 4 m-diameter segmented reflector dish and an innovative fully digital camera based on silicon photo-multipliers. Since SST sub-array consist up to 70 telescopes, challenge not only build excellent performance, but also design them so that their components can commissioned, assembled tested by industry. In this paper...
We report Earth-scale distance magnetic correlations from lightning strokes in the frequency range 1-1000 Hz at several distances ranging 1100 to 9000 km. Noise sources which are correlated on can affect future searches for gravitational-wave signals with ground-based interferometric detectors. consider impact of field fluctuations due Schumann resonances ($<$50 Hz) as well higher frequencies ($>$100 Hz). demonstrate that individual a likely source observed observatories and discuss some...
In July 2021, PKS 1510-089 exhibited a significant flux drop in the high-energy gamma-ray (by factor 10) and optical 5) bands remained this low state throughout 2022. Similarly, polarization source vanished, resulting spectrum being fully explained through steady of accretion disk broad-line region. Unlike aforementioned bands, very-high-energy X-ray fluxes did not exhibit from year to year. This suggests that steady-state originate different emission region than vanished parts jet fluxes....
The process of cosmic ray first-order Fermi acceleration at relativistic shock waves is studied with the method Monte Carlo simulations. simulations are based on numerical integration particle equations motion in a turbulent magnetic field near shock. In comparison to earlier studies, few "realistic" features structure included. upstream consists mean component inclined some angle normal finite-amplitude sinusoidal perturbations imposed upon it. assumed be static local plasma rest frame....