Ruslan Konno
A5071513464- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Dark Matter and Cosmic Phenomena
- Pulsars and Gravitational Waves Research
- Radio Astronomy Observations and Technology
- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Astronomical Observations and Instrumentation
- Cosmology and Gravitation Theories
- Stellar, planetary, and galactic studies
- Infrared Target Detection Methodologies
- Laser-Plasma Interactions and Diagnostics
- Galaxies: Formation, Evolution, Phenomena
- Seismology and Earthquake Studies
- Astronomy and Astrophysical Research
- Solar and Space Plasma Dynamics
- Astro and Planetary Science
- Geophysics and Gravity Measurements
- Advanced Measurement and Detection Methods
- Calibration and Measurement Techniques
- Nuclear Physics and Applications
- Earthquake Detection and Analysis
- Particle Detector Development and Performance
- Planetary Science and Exploration
Weizmann Institute of Science
2024
Institut de Recherche sur les Lois Fondamentales de l'Univers
2021-2023
ETH Zurich
2023
Max Planck Institute for Physics
2023
École Polytechnique
2023
Deutsches Elektronen-Synchrotron DESY
2021-2023
CEA Paris-Saclay
2021-2023
Université Paris-Saclay
2021-2023
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2021-2023
University of Würzburg
2023
Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, associated with stellar core collapse events. We report the detection very-high-energy (VHE) GRB 190829A, between 4 and 56 hours after trigger, using High Energy Stereoscopic System (H.E.S.S.). The low luminosity redshift 190829A reduce both internal external absorption, allowing determination its intrinsic energy spectrum. Between energies 0.18 3.3 tera-electron...
Recurrent Novae are repeating thermonuclear explosions in the outer layers of white dwarfs, due to accretion fresh material from a binary companion. The shock generated by ejected slamming into companion star's wind, accelerates particles very-high-energies. We report very-high-energy (VHE, $\gtrsim100$\,GeV) gamma rays recurrent nova RS\,Ophiuchi up month after its 2021 outburst, using High Energy Stereoscopic System. VHE emission has similar temporal profile lower-energy GeV emission,...
Abstract The Large Array Survey Telescope (LAST) is a wide-field visible-light telescope array designed to explore the variable and transient sky with high cadence. LAST will be composed of 48, 28 cm f/2.2 telescopes (32 already installed) equipped full-frame backside-illuminated cooled CMOS detectors. Each provides field view (FoV) 7.4 deg 2 1.″25 pix −1 , while system FoV 355 in 2.9 Gpix. total collecting area LAST, 48 telescopes, equivalent 1.9 m telescope. cost-effectiveness (i.e.,...
GRB221009A is the brightest gamma-ray burst ever detected. To probe very-high-energy (VHE, $>$\!100 GeV) emission, High Energy Stereoscopic System (H.E.S.S.) began observations 53 hours after triggering event, when brightness of moonlight no longer precluded observations. We derive differential and integral upper limits using H.E.S.S. data from third, fourth, ninth nights initial GRB detection, applying atmospheric corrections. The combined yield an energy flux limit $\Phi_\mathrm{UL}^{95\%}...
Cosmological and astrophysical observations suggest that 85% of the total matter Universe is made Dark Matter (DM). However, its nature remains one most challenging fundamental open questions particle physics. Assuming DM, this exotic form cannot consist Standard Model (SM) particles. Many models have been developed to attempt unraveling DM such as Weakly Interacting Massive Particles (WIMPs), favored candidates. WIMP annihilations decay could produce SM particles which in turn hadronize...
The flat spectrum radio quasar (FSRQ) PKS 1510−089 is known for its complex multiwavelength behaviour and it one of only a few FSRQs detected in very-high-energy (VHE, E > 100 GeV) γ rays. VHE -ray observations with H.E.S.S. MAGIC late May early June 2016 resulted the detection an unprecedented flare, which revealed, first time, intranight variability this source. While common timescale 1.5 h has been found, there significant deviation near end ∼20 min marking cessation event. peak flux...
The High Altitude Water Cherenkov (HAWC) observatory and the Energy Stereoscopic System (H.E.S.S.) are two leading instruments in ground-based very-high-energy gamma-ray domain. HAWC employs water detection (WCD) technique, while H.E.S.S. is an array of Imaging Atmospheric Telescopes (IACTs). facilities therefore differ multiple aspects, including their observation strategy, size field view angular resolution, to different analysis approaches. Until now, it has been unclear if results...
We report on the detection of very-high-energy (VHE; $E > 100$ GeV) $\gamma$-ray emission from BL Lac objects KUV 00311-1938 and PKS 1440-389 with High Energy Stereoscopic System (H.E.S.S.). H.E.S.S. observations were accompanied or preceded by multi-wavelength Fermi/LAT, XRT UVOT board Swift satellite, ATOM. Based an extrapolation Fermi/LAT spectrum towards VHE regime, we deduce a 95% confidence level upper limit unknown redshift z < 0.98, 0.53. When combined previous spectroscopy results...
The binary system $\eta$ Carinae is a unique laboratory in which to study particle acceleration high energies under wide range of conditions, including extremely densities around periastron. To date, no consensus has emerged as the origin GeV $\gamma$-ray emission this important system. With re-analysis full Fermi-LAT dataset for we show that spectrum consistent with pion decay origin. A single population leptonic model connecting X-ray can be ruled out. Here, revisit physical Ohm et al....
Abstract We report on the observations of four well-localized binary black hole (BBH) mergers by High Energy Stereoscopic System (H.E.S.S.) during second and third observing runs Advanced LIGO Virgo, O2 O3. H.E.S.S. can observe 20 deg 2 sky at a time follows up gravitational-wave (GW) events “tiling” localization regions to maximize covered probability. During O3, observed large portions regions, between 35% 75%, for BBH (GW170814, GW190512_180714, GW190728_064510, S200224ca). For these GW...
Primordial Black Holes are expected to be formed in the early Universe by gravitational collapse of overdense regions, among other mechanisms. They also loose their mass over time Hawking radiation process. As rates this increase with temperature, PBH evaporation should result a violent explosion. The current upper limits on explosion order $10^4-10^5 pc^{-3}yr^{-1}$. In contribution we'll present results search for TeV $\gamma$-ray burst within timescale few seconds, using nearly 5000 hours...
Highly extended gamma-ray emission around the Geminga pulsar was discovered by Milagro and verified HAWC. Despite many observations with Imaging Atmospheric Cherenkov Telescopes (IACTs), detection of on angular scales exceeding IACT field-of-view has proven challenging. Recent developments in analysis techniques have enabled significant archival data H.E.S.S.. In 2019, further region were obtained an adapted observation strategy. Following announcement TeV data, this contribution we present...
Detection of moving sources over complicated background is important for several reasons. First measuring the astrophysical motion source. Second that such resulting from atmospheric scintillation, color refraction, or reasons a major source false alarms image subtraction methods. We extend Zackay, Ofek, and Gal-Yam formalism to deal with sources. The new method, named translient (translational transient) detector, applies hypothesis testing between stationary moving. It can be used detect...
Abstract Detection of moving sources over a complicated background is important for several reasons. First measuring the astrophysical motion source. Second that such resulting from atmospheric scintillation, color refraction, or reasons major source false alarms image-subtraction methods. We extend Zackay, Ofek, and Gal-Yam formalism to deal with sources. The new method, named translient (translational transient) detector, applies hypothesis testing between stationary moving. It can be used...
Transforming the instrumental photometry of ground-based telescopes into a calibrated physical flux in well-defined passband is major challenge astronomy. Along with intrinsic difference between sharing same filter, effective transmission continuously modified by effects variable atmosphere Earth. We have developed new approach to absolute photometric calibration that simultaneously treats and atmospheric on an image-by-image basis fitting system transmission. This aims at breaking 1%...
The Fermi Bubbles were discovered about a decade ago in the Fermi-LAT data as double-lobe structure extending up to 55° Galactic latitudes above and below Center. At moment their origin is still unknown. H.E.S.S. collaboration currently performing first ever survey TeV gamma rays of Milky Way inner region: Inner Galaxy Survey. This intended achieve best sensitivity faint diffuse emissions region several degrees around Centre. It provides an unprecedented dark matter signals, new emissions,...
Abstract Cosmological N -body simulations show that Milky Way–sized galaxies harbor a population of unmerged dark matter (DM) subhalos. These subhalos could shine in gamma-rays and eventually be detected gamma-ray surveys as unidentified sources. We performed thorough selection among Fermi-Large Area Telescope Objects (UFOs) to identify them possible tera-electron-volt-scale DM subhalo candidates. search for very-high-energy (E ≳ 100 GeV) emissions using H.E.S.S. observations toward four...
The identification of active PeVatrons, hadronic particle accelerators reaching the knee cosmic-ray spectrum (at energy few PeV), is crucial to understand origin cosmic rays in Galaxy. In this context, we report on new H.E.S.S. observations PeVatron candidate HESS J1702-420, which bring evidence for presence γ-rays up 100 TeV. This first time history that photons with such high are observed. Remarkably, deep allowed discovery a γ-ray source component, called J1702-420A, was previously hidden...
Kepler’s supernova remnant (SNR) which is produced by the most recent naked-eye in our Galaxy one of best studied SNRs, but its gamma-ray detection has eluded us so far. Observations with modern imaging atmospheric Cherenkov telescopes (IACT) have enlarged knowledge about nearby SNRs ages younger than 500 years establishing Cassiopeia A and Tycho’s as very high energy (VHE) sources setting a lower limit on distance to SNR. This SNR significantly more distant other two expected be faintest...
Detecting and studying galactic gamma-ray sources emitting very-high energy photons sheds light on the acceleration propagation of cosmic rays presumably created in these sources. Currently, there are few with energies exceeding 100 TeV. In this work we revisit unidentified source MGRO J1908+06, initially detected by Milagro, using an updated H.E.S.S. dataset analysis pipeline. The vicinity contains a supernova remnant pulsars as well molecular clouds. This makes identification primary...
The presence of dark matter (DM) is suggested by a wealth astrophysical and cosmological measurements. However, its underlying nature yet unknown. Among the most promising candidates are weakly interacting massive particles (WIMPs): with mass coupling strength at electroweak scale thermally produced in early universe have present relic density consistent that observed today. WIMP self-annihilation would produce Standard Model including gamma-rays, which been long-time recognized as prime...
GRB221009A is the brightest gamma-ray burst ever detected. To probe very-high-energy (VHE, $>$\!100 GeV) emission, High Energy Stereoscopic System (H.E.S.S.) began observations 53 hours after triggering event, when brightness of moonlight no longer precluded observations. We derive differential and integral upper limits using H.E.S.S. data from third, fourth, ninth nights initial GRB detection, applying atmospheric corrections. The combined yield an energy flux limit $Φ_\mathrm{UL}^{95\%}...
Tidal Disruption Events (TDEs) are a relatively young class of transient phenomena, which occur whenever star approaches supermassive black hole (SMBH) close enough to be ripped apart by its tidal forces. Part the stellar debris forms an accretion disk, in turn may result flare electromagnetic radiation, is typically detected optical/UV and X-ray energy bands. Some TDEs have also been radio non-thermal X-rays, suggests active particle acceleration relativistic energies likely shocks or jets....
Gravitational wave (GW) events, particularly those connected to the merger of compact objects such as neutron stars, are believed be primary source short gamma-ray bursts. To explore very high energy (VHE) component emission from these H.E.S.S. collaboration has dedicated a substantial effort and observing time follow up on events. During second third GW runs, was first ground-based instrument observe GW170817 binary star merger. In addition, followed four black hole mergers. The data...
Gravitational wave (GW) events, particularly those connected to the merger of compact objects such as neutron stars, are believed be primary source short gamma-ray bursts. To explore very high energy (VHE) component emission from these H.E.S.S. collaboration has dedicated a substantial effort and observing time follow up on events. During second third GW runs, was first ground-based instrument observe GW170817 binary star merger. In addition, followed four black hole mergers. The data...