J. Katsuta
A5032633625- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Particle Detector Development and Performance
- Astrophysical Phenomena and Observations
- Nuclear Physics and Applications
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Advanced Semiconductor Detectors and Materials
- Advanced X-ray and CT Imaging
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Radio Astronomy Observations and Technology
- Medical Imaging Techniques and Applications
- Calibration and Measurement Techniques
- Stellar, planetary, and galactic studies
- Advanced X-ray Imaging Techniques
- Pulsars and Gravitational Waves Research
- Radiation Therapy and Dosimetry
- Astrophysics and Star Formation Studies
- Optical Systems and Laser Technology
- Infrared Target Detection Methodologies
- Galaxies: Formation, Evolution, Phenomena
- Particle Accelerators and Free-Electron Lasers
- Radiomics and Machine Learning in Medical Imaging
- Neutrino Physics Research
Hiroshima University
2014-2020
Urology Team
2018
SLAC National Accelerator Laboratory
2012-2016
Institut de Recherche sur les Lois Fondamentales de l'Univers
2016
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2016
CEA Paris-Saclay
2016
Laboratoire de Physique des deux infinis Bordeaux
2016
Max Planck Institute for Nuclear Physics
2016
Tokyo Metropolitan University
2016
Goddard Space Flight Center
2016
We present the third Fermi Large Area Telescope (LAT) source catalog (3FGL) of sources in 100 MeV–300 GeV range. Based on first 4 yr science data from Gamma-ray Space mission, it is deepest yet this energy Relative to Second LAT catalog, 3FGL incorporates twice as much data, well a number analysis improvements, including improved calibrations at event reconstruction level, an updated model for Galactic diffuse γ-ray emission, refined procedure detection, and methods associating with...
Cosmic rays are particles (mostly protons) accelerated to relativistic speeds. Despite wide agreement that supernova remnants (SNRs) the sources of galactic cosmic rays, unequivocal evidence for acceleration protons in these objects is still lacking. When encounter interstellar material, they produce neutral pions, which turn decay into gamma rays. This offers a compelling way detect sites protons. The identification pion-decay has been difficult because high-energy electrons also via...
Abstract The in-orbit performance and calibration of the Hard X-ray Detector (HXD) on board astronomy satellite Suzaku are described. Its basic performances, including a wide energy bandpass 10–600 keV, resolutions $\sim 4 \,\mathrm{keV}$ (FWHM) at 40 keV 11\%$ 511 high background rejection efficiency, have been confirmed by extensive calibrations. long-term gains PIN-Si diodes stable within 1% for half year, those scintillators decreased 5–20%. residual non-X-ray HXD is lowest among past...
Recent observations of supernova remnants (SNRs) hint that they accelerate cosmic rays to energies close ~10(15) electron volts. However, the nature particles produce emission remains ambiguous. We report SNR W44 with Fermi Large Area Telescope at between 2 x 10(8) volts and 3 x10(11) The detection a source morphology corresponding shell implies is produced by accelerated there. gamma-ray spectrum well modeled from protons nuclei. Its steepening above approximately 10(9) provides probe which...
The discovery of bright gamma-ray emission coincident with supernova remnant (SNR) W51C is reported using the Large Area Telescope (LAT) on board Fermi Gamma-ray Space Telescope. a middle-aged (~10^4 yr) intense radio synchrotron in its shell and known to be interacting molecular cloud. spatially extended, broadly consistent X-ray extent SNR W51C. energy spectrum 0.2-50 GeV band exhibits steepening toward high energies. luminosity greater than 1x10^{36} erg/s given distance constraint D>5.5...
ABSTRACT To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed first systematic survey energies from 1 to 100 GeV using data Fermi Large Area Telescope (LAT). Based on spatial overlap sources detected with SNRs known radio surveys, classify 30 as likely SNRs. We also report 14 marginal associations and 245 flux upper limits. A mock catalog in which positions are scrambled Galactic longitude allows us an limit 22% number candidates falsely...
Abstract High-resolution X-ray spectroscopy with Hitomi was expected to resolve the origin of faint unidentified emission line reported in several low-resolution studies various massive systems, such as galaxies and clusters, including Perseus cluster. We have analyzed first-light observation The for based on XMM-Newton signal from large cluster sample under dark matter decay scenario is too be detectable data. However, previously 3.5 keV flux anomalously high compared sample-based...
We present an analysis of the gamma-ray data obtained with Large Area Telescope (LAT) on board Fermi Gamma-ray Space in direction SNR W49B (G43.3−0.2). A bright unresolved source detected at a significance 38σ is found to coincide W49B. The energy spectrum 0.2–200 GeV range gradually steepens toward high energies. luminosity estimated be 1.5 × 1036 (D/8 kpc)2 erg s−1 this range. There no indication that emission comes from pulsar. Assuming supernova remnant (SNR) shell site production,...
The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions developed by Institute Space and Astronautical Science (ISAS), with planned launch 2015. equipped suite sensitive instruments highest energy resolution ever achieved at E > 3 keV wide range spanning four decades from soft X-rays to gamma-rays. simultaneous broad band pass, coupled high spectral Delta < 7 eV micro-calorimeter, will enable variety important science themes be pursued. expected...
The Hitomi (ASTRO-H) mission is the sixth Japanese X-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. aimed to provide highest energy resolution ever achieved at E > 2 keV, using microcalorimeter instrument, cover wide range spanning four decades in from soft X-rays gamma-rays. After successful launch on 2016 February 17, spacecraft lost its function March 26, but commissioning phase for about month provided valuable...
We report the detection of GeV γ-ray emission from molecular cloud complex that surrounds supernova remnant (SNR) W44 using Large Area Telescope on board Fermi. While previously reported SNR is likely to arise dense radio-emitting filaments within remnant, appears come surrounding can be ascribed cosmic rays (CRs) have escaped W44. The non-detection synchrotron radio associated with suggests decay π0 mesons produced in hadronic collisions as mechanism. total kinetic energy channeled into...
The hard x-ray imaging spectroscopy system of "Hitomi" observatory is composed two sets imagers (HXI) coupled with telescopes (HXT). With a 12-m focal length, the provides fine (1 ′ . 7 half-power diameter) covering about 5 to 80 keV. HXI sensor consists camera, which four layers Si and one layer CdTe semiconductor imagers, an active shield nine Bi4Ge3O12 scintillators provide low background. HXIs started observation on March 8 14, 2016 were operational until 26 March. Using Crab...
We present an analysis of gamma-ray data obtained with the Large Area Telescope on board Fermi Gamma-ray Space in region around supernova remnant (SNR) S147 (G180.0−1.7). A spatially extended source detected energy range 0.2–10 GeV is found to coincide SNR S147. confirm its spatial extension at >5σ confidence level. The flux (3.8 ± 0.6) × 10−8 photons cm−2 s−1, corresponding a luminosity 1.3 1034 (d/1.3 kpc)2 erg s−1 this range. emission exhibits possible correlation prominent Hα filaments...
The 6th Japanese X-ray satellite, ASTRO-H, is scheduled for launch in 2015. hard focusing imaging system will observe astronomical objects with the sensitivity detecting point sources a brightness of 1/100,000 times fainter than Crab nebula at > 10 keV. Hard Imager (HXI) focal plane detector 12 m below telescope (HXT) covering energy range from 5 to 80 HXI composed stacked Si/CdTe semiconductor module and surrounding BGO scintillators. latter work as active shields efficient reduction...
Abstract We report a study of extended γ -ray emission with the Large Area Telescope (LAT) on board Fermi Gamma-ray Space , which is likely to be second case detection from star-forming region (SFR) in our Galaxy. The LAT source located G25 region, 1.°7 × 2.°1 around ( l b ) = (25.°0, 0.°0). found composed two sources and one pointlike source. have similar sizes about 1.°4 0.°6. An ∼0.°4 diameter subregion has photon index Γ 1.53 ± 0.15, spatially coincident HESS J1837−069, pulsar wind...
Centaurus B is a nearby radio galaxy positioned in the Southern hemisphere close to Galactic plane. Here we present detailed analysis of about 43 months accumulated Fermi-LAT data gamma-ray counterpart source initially reported 2nd catalog, and newly acquired Suzaku X-ray data. We confirm its detection at GeV photon energies, analyze extension variability LAT dataset, which it appears as steady emitter. The core detected bright continuum radiation. do not detect however any diffuse emission...
Hitomi X-ray observatory launched in 17 February 2016 had a hard imaging spectroscopy system made of two imagers (HXIs) coupled with telescopes (HXTs). With 12 m focal length, they provide fine (2' half-power diameter; HPD) at 5 to 80 keV. The HXI main are 4 layers Si and CdTe semiconductor double-sided strip detectors, stacked enhance detection efficiency as well enable photon interaction-depth sensing. Active shield 9 BGO scintillators surrounds the imager low background. Following...
The Soft Gamma-ray Detector (SGD) is one of science instruments onboard ASTRO-H (Hitomi) and features a wide energy band 60{600 keV with low backgrounds. SGD an instrument novel concept "Narrow field-of-view" Compton camera where kinematics utilized to reject backgrounds which are inconsistent the field-of-view defined by active shield. After several years developments, flight hardware was fabricated subjected subsystem tests satellite system tests. successful launch on February 17, 2016...