A5076360489- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Radio Astronomy Observations and Technology
- Neutrino Physics Research
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Astronomy and Astrophysical Research
- Radiation Detection and Scintillator Technologies
- Geophysics and Gravity Measurements
- Solar and Space Plasma Dynamics
- Particle physics theoretical and experimental studies
- Particle Accelerators and Free-Electron Lasers
- Distributed and Parallel Computing Systems
- Advanced Computational Techniques and Applications
- Radiation Therapy and Dosimetry
- Adaptive optics and wavefront sensing
- Atomic and Subatomic Physics Research
- Spacecraft Design and Technology
- Atmospheric Ozone and Climate
- Methane Hydrates and Related Phenomena
- Stellar, planetary, and galactic studies
- Galaxies: Formation, Evolution, Phenomena
The University of Tokyo
2009-2024
Universitat de Barcelona
2024
Institut d'Estudis Espacials de Catalunya
2024
TU Dortmund University
2023
University of Łódź
2023
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
2023
University of Turku
2023
Niels Brock
2023
University of Copenhagen
2023
Main Astronomical Observatory
2023
We have detected sub-TeV gamma-ray emission from the direction of Galactic center (GC) using CANGAROO-II Imaging Atmospheric Cerenkov Telescope. a statistically significant excess at energies greater than 250 GeV. The flux was 1 order magnitude lower that Crab Nebula TeV with soft spectrum proportional to E-4.6±0.5. signal centroid is consistent GC direction, and observed profile pointlike source. Our data suggest GeV source 3EG J1746-2851 identical this source, we study combined spectra...
We have detected gamma-ray emission at the 6sigma level energies greater than 500GeV from supernova remnant RX J0852.0-4622 (G266.2-1.2) using CANGAROO-II Imaging Atmospheric Cherenkov Telescope (IACT). The flux was 0.12 times of that Crab 1TeV. signal centroid is consistent with peak X-ray in north-west rim remnant.
Observations of the PSR B1259-63/SS2883 binary system using CANGAROO-II Cherenkov telescope are reported. This nearby consists a 48msec radio pulsar in highly eccentric orbit around Be star, and offers unique laboratory to investigate interactions between outflows star at various distances. It has been pointed out that relativistic wind dense mass outflow may result emission gamma rays up TeV energies. We have observed 2000 2001, 47 157 days after October periastron. Upper limits 0.13--0.54...
We made stereoscopic observations of the Vela pulsar region with two 10 m diameter CANGAROO-III imaging atmospheric Cerenkov telescopes in 2004 January and February a search for sub-TeV gamma rays from surrounding regions. describe observations, provide detailed account calibration methods, introduce improved bias-free analysis techniques employed data. No evidence gamma-ray emission is found either position or previously reported offset by 013, resulting upper limits are factor 5 less than...
Sub-TeV gamma-ray emission from the North-West rim of supernova remnant RX J0852.0$-$4622 was detected with CANGAROO-II telescope and recently confirmed by H.E.S.S. group. In addition, data revealed a very wide (up to two degrees in diameter), shell-like profile emission. We have carried out CANGAROO-III observations January February 2005 three telescopes show here results three-fold coincidence data. confirm about morphology energy spectrum, find spectrum NW-rim is consistent that whole remnant.
We have observed the giant radio galaxy Centaurus A and globular cluster $ω$ Centauri in TeV energy region using CANGAROO-III stereoscopic system. The system has been operation since 2004 withan array of four Imaging Atmospheric Cherenkov Telescopes (IACT) with $\sim$100-m spacings. observations were carried out March April 2004. In total, approximately 10 hours data obtained for each target.No statistically significant gamma-ray signal found above 420 GeV over a wide angular (a one-degree...
Because accretion and merger shocks in clusters of galaxies may accelerate particles to high energies, are candidate sites for the origin ultra-high-energy (UHE) cosmic rays. A prediction was presented gamma-ray emission from a cluster at detectable level with current generation imaging atmospheric Cherenkov telescopes. The produced via inverse Compton upscattering microwave background photons by electron–positron pairs generated collisions UHE rays cluster. We observed two galaxies, Abell...
TeV gamma-rays were recently detected from the nearby normal spiral galaxy NGC 253 (Itoh et al. 2002).Observations to detect Cherenkov light images initiated by direction of carried out in 2000 and 2001 over a total period ∼150 hours.The orientation gamma-ray-like events is not consistent with emission point source, region corresponds size greater than 10 kpc radius.Here, detailed descriptions analysis procedures techniques are given.
We report the TeV gamma-ray observations of nearby normal spiral galaxy NGC 253.At a distance ∼2.5 Mpc, 253 is one nearest starburst galaxies.This relative closeness, coupled with high star formation rate in galaxy, make it good candidate source.Observations were carried out 2000 and 2001 CANGAROO-II 10 m imaging atmospheric Cerenkov telescope.TeV emission detected at ∼11σ level flux (7.8 ± 2.5) × -12 cm -2 s -1 energies >0.5 TeV.The data indicate that region broader than point spread...
We have used the CANGAROO-III imaging atmospheric Cherenkov telescopes to observe high-frequency-peaked BL Lacertae (HBL) object PKS 2155-304 between 2006 July 28 (MJD 53944) and August 2, triggered by H.E.S.S. report that source was in a high state of TeV gamma-ray emission. A signal detected at 4.8 sigma level an effective live time 25.1 hours during outburst period. The flux Very High Energy gammarays from observations shows variability on scale less than few hours. averaged integral...
We have observed the supernova remnant MSH 15-52 (G320.4-1.2), which contains gamma-ray pulsar PSR B1509-58, using CANGAROO-III imaging atmospheric Cherenkov telescope array from April to June in 2006. detected gamma rays above 810 GeV at 7 sigma level during a total effective exposure of 48.4 hours. obtained differential flux 2.35 TeV (7.9+/-1.5_{stat}+/-1.7_{sys}) \times 10^{-13} cm^{-2}s^{-1}TeV^{-1} with photon index 2.21+/-0.39_{stat}+/-0.40_{sys}, is compatible that H.E.S.S....
Abstract Imaging atmospheric Cherenkov telescopes (IACTs) are ground-based indirect detectors for cosmic gamma rays with energies above tens of GeV. The major backgrounds gamma-ray observations in IACTs cosmic-ray charged particles. capability to reject these is the most important factor determining sensitivity IACT systems. Monte Carlo simulations used estimate residual background rates and systems during design construction phase. Uncertainties modeling high-energy hadronic interactions...
We have observed Markarian 421 in January and March 2001 with the CANGAROO-II imaging Cherenkov telescope during an extraordinarily high state at TeV energies. From 14 hours observations very large zenith angles, $\sim70^\circ$, a signal of 298 $\pm$ 52 gamma-ray--like events (5.7 $σ$) was detected $E>10$ TeV, where higher sensitivity is achieved than those usual near zenith, owing to greatly increased collecting area. Under assumption intrinsic power-law spectrum, we derived differential...
Aims.The CANGAROO-II telescope observed sub-TeV gamma-ray emission from the nearby starburst galaxy NGC 253. The region was extended with a radial size of 0.3–0.6 degree. On contrary, HESS could not confirm this and gave upper limits at level flux. In order to resolve discrepancy, we analyzed new observational results for 253 by CANGAROO-III also assessed CANGAROO-II.
The Large Size Telescopes, LSTs, located at the center of Cherenkov Telescope Array, CTA, will be sensitive for low energy gamma-rays. camera on LST focal plane is optimized to detect events based a high photon detection efficiency and speed electronics. Also trigger system designed showers as much possible. In addition, required work stably without maintenance in few tens years. this contribution we present design first status its development production.
We observed the unidentified TeV gamma-ray source HESS J1804-216 with CANGAROO-III atmospheric Cerenkov telescopes from May to July in 2006. detected very high energy gamma rays above 600 GeV at 10 sigma level an effective exposure of 76 hr. obtained a differential flux (5.0+/-1.5_{stat}+/-1.6_{sys})\times 10^{-12}(E/1 TeV)^{-\alpha} cm^{-2}s^{-1}TeV^{-1} photon index \alpha 2.69 +/- 0.30_{stat} 0.34_{sys}, which is consistent that H.E.S.S. observation 2004. also confirm extended morphology...
The Cherenkov Telescope Array (CTA) project aims to implement the world's largest next generation of Very High Energy gamma-ray Imaging Atmospheric Telescopes devoted observation from a few tens GeV more than 100 TeV.To view whole sky, two CTA sites are foreseen, one for each hemisphere.The sensitivity at lowest energy range will be dominated by four Large Size Telescopes, LSTs, located center array and designed achieve observations high red-shift objects with threshold 20 GeV.The LST is...
Cold, dense gas clouds have been proposed as a major component of Galactic dark matter; such can be revealed by the gamma-ray emission that arises from cosmic rays interacting with gas. If this matter is clustered, then highly luminous GeV sources result, preferentially at low-to-mid latitudes, where they lie within cosmic-ray disk. The predicted for clusters steady, continuum peak power emerging several hundred MeV. These would not obvious counterparts other wavelengths and are thus...