Publications (30)
Detection of high-energy gamma rays from winter thunderclouds
H. Tsuchiya, T. Enoto, S. Yamada +8
A report is made on a comprehensive observation of a burst-like -ray emission from thunderclouds on the Sea of Japan, during strong thunderstorms on 2007 January 6. The detecte…
The design and performance of the XL-Calibur anticoincidence shield
N. K. Iyer, M. Kiss, M. Pearce +31
The XL-Calibur balloon-borne hard X-ray polarimetry mission comprises a Compton-scattering polarimeter placed at the focal point of an X-ray mirror. The polarimeter is housed withi…
X-ray Diagnostics of Thermal Conditions of the Hot Plasmas in the Centaurus Cluster
I. Takahashi, M. Kawaharada, K. Makishima +9
X-ray data of the Centaurus cluster, obtained with {\it XMM-Newton} for 45 ksec, were analyzed. Deprojected EPIC spectra from concentric thin shell regions were reproduced equally…
X-ray polarimetry of X-ray pulsar X Persei: another orthogonal rotator?
A. A. Mushtukov, S. S. Tsygankov, J. Poutanen +103
X Persei is a persistent low-luminosity X-ray pulsar of period of 835 s in a Be binary system. The field strength at the neutron star surface is not known precisely, but indi…
The geometry of the hot corona in MCG-05-23-16 constrained by X-ray polarimetry
D. Tagliacozzo, A. Marinucci, F. Ursini +105
We report on the second observation of the radio-quiet active galactic nucleus (AGN) MCG-05-23-16 performed with the Imaging X-ray Polarimetry Explorer (IXPE). The observation star…
The X-ray polarisation of the Seyfert 1 galaxy IC 4329A
A. Ingram, M. Ewing, A. Marinucci +105
We present an X-ray spectro-polarimetric analysis of the bright Seyfert galaxy IC 4329A. The Imaging X-ray Polarimetry Explorer (IXPE) observed the source for ~500 ks, supported by…
Hard X-ray Detector (HXD) on Board Suzaku
T. Takahashi, K. Abe, M. Endo +66
The Hard X-ray Detector (HXD) on board Suzaku covers a wide energy range from 10 keV to 600 keV by combination of silicon PIN diodes and GSO scintillators. The HXD is designed to a…
IXPE observation confirms a high spin in the accreting black hole 4U 1957+115
L. Marra, M. Brigitte, N. Rodriguez Cavero +113
We present the results of the first X-ray polarimetric observation of the low-mass X-ray binary 4U 1957+115, performed with the Imaging X-ray Polarimetry Explorer in May 2023. The…
X-ray polarimetry and spectroscopy of the neutron star low-mass X-ray binary GX 9+9: an in-depth study with IXPE and NuSTAR
F. Ursini, R. Farinelli, A. Gnarini +101
We report on a comprehensive analysis of simultaneous X-ray polarimetric and spectral data of the bright atoll source GX 9+9 with the Imaging X-ray Polarimetry Explorer (IXPE) and…
Rapid Variability of Blazar 3C 279 during Flaring States in 2013-2014 with Joint Fermi-LAT, NuSTAR, Swift, and Ground-Based Multi-wavelength Observations
M. Hayashida, K. Nalewajko, G. M. Madejski +49
We report the results of a multi-band observing campaign on the famous blazar 3C 279 conducted during a phase of increased activity from 2013 December to 2014 April, including firs…
X-ray polarization measurement of the gold standard of radio-quiet active galactic nuclei : NGC 1068
F. Marin, A. Marinucci, M. Laurenti +102
We used the Imaging X-ray Polarimetry Explorer (IXPE) satellite to measure, for the first time, the 2-8 keV polarization of NGC 1068. We pointed IXPE for a net exposure time of 1.1…
Polarization constraints on the X-ray corona in Seyfert Galaxies: MCG-05-23-16
A. Marinucci, F. Muleri, M. DovÄiak +97
We report on the first observation of a radio-quiet Active Galactic Nucleus (AGN) using polarized X-rays: the Seyfert 1.9 galaxy MCG-05-23-16. This source was pointed with the Imag…
Performance of the PRAXyS X-ray Polarimeter
W. B. Iwakiri, J. K. Black, R. Cole +11
The performance of the Time Projection Chamber (TPC) polarimeter for the Polarimeter for Relativistic Astrophysical X-ray Sources (PRAXyS) Small Explorer was evaluated using polari…
Uncovering the geometry of the hot X-ray corona in the Seyfert galaxy NGC4151 with IXPE
V. E. Gianolli, D. E. Kim, S. Bianchi +106
We present an X-ray spectro-polarimetric analysis of the bright Seyfert galaxy NGC4151. The source has been observed with the Imaging X-ray Polarimetry Explorer (IXPE) for 700 ks,…
XL-Calibur -- a second-generation balloon-borne hard X-ray polarimetry mission
Q. Abarr, H. Awaki, M. G. Baring +38
XL-Calibur is a hard X-ray (15-80 keV) polarimetry mission operating from a stabilised balloon-borne platform in the stratosphere. It builds on heritage from the X-Calibur mission,…
Cyclotron resonance energies at a low X-ray luminosity: A0535+262 observed with Suzaku
Y. Terada, T. Mihara, M. Nakajima +28
The binary X-ray pulsar A0535+262 was observed with the Suzaku X-ray observatory, on 2005 September 14 for a net exposure of 22 ksec. The source was in a declining phase of a minor…
Mapping the circumnuclear regions of the Circinus galaxy with the Imaging X-ray Polarimetry Explorer
F. Ursini, A. Marinucci, G. Matt +94
We report on the Imaging X-ray Polarimetry Explorer (IXPE) observation of the closest and X-ray brightest Compton-thick active galactic nucleus (AGN), the Circinus galaxy. We find…
Design, Construction, and Test of the Gas Pixel Detectors for the IXPE Mission
L. Baldini, M. Barbanera, R. Bellazzini +91
Due to be launched in late 2021, the Imaging X-Ray Polarimetry Explorer (IXPE) is a NASA Small Explorer mission designed to perform polarization measurements in the 2-8 keV band, c…
Gas selection for Xe-based LCP-GEM detectors onboard the CubeSat X-ray observatory NinjaSat
T. Takeda, T. Tamagawa, T. Enoto +18
We present a gas selection for Xe-based gas electron multiplier (GEM) detectors, Gas Multiplier Counters (GMCs) onboard the CubeSat X-ray observatory NinjaSat. To achieve an energy…
First NuSTAR observations of the BL Lac - type blazar PKS~2155-304: constraints on the jet content and distribution of radiating particles
G. M. Madejski, K. Nalewajko, K. K. Madsen +35
We report the first hard X-ray observations with NuSTAR of the BL Lac type blazar PKS 2155-304, augmented with soft X-ray data from XMM-Newton and gamma-ray data from the Fermi Lar…
The NuSTAR Extragalactic Surveys: The Number Counts of Active Galactic Nuclei and the Resolved Fraction of the Cosmic X-ray Background
F. A. Harrison, J. Aird, F. Civano +41
We present the 3-8 keV and 8-24 keV number counts of active galactic nuclei (AGN) identified in the NuSTAR extragalactic surveys. NuSTAR has now resolved 33-39% of the X-ray backgr…
In-Orbit Performance of the Hard X-ray Detector on board Suzaku
M. Kokubun, K. Makishima, T. Takahashi +52
The in-orbit performance and calibration of the Hard X-ray Detector (HXD) on board the X-ray astronomy satellite Suzaku are described. Its basic performances, including a wide ener…
Hardening and termination of long-duration gamma rays detected prior to lightning
H. Tsuchiya, T. Enoto, K. Iwata +10
We report the first observation of 330 MeV prolonged gamma-ray emission that was abruptly terminated by lightning. The gamma-ray detection was made during winter thunderstorms o…
Observations of a GX 301-2 Apastron Flare with the X-Calibur Hard X-Ray Polarimeter Supported by NICER, the Swift XRT and BAT, and Fermi GBM
Q. Abarr, M. Baring, B. Beheshtipour +28
The accretion-powered X-ray pulsar GX 301-2 was observed with the balloon-borne X-Calibur hard X-ray polarimeter during late December 2018, with contiguous observations by the NICE…
Asymmetries in core-collapse supernovae from maps of radioactive Ti in CassiopeiaA
B. W. Grefenstette, F. A. Harrison, S. E. Boggs +28
Asymmetry is required by most numerical simulations of stellar core-collapse explosions, but the form it takes differs significantly among models. The spatial distribution of radio…
Multiwavelength Study of Quiescent States of Mrk 421 with Unprecedented Hard X-Ray Coverage Provided by NuSTAR in 2013
M. BalokoviÄ, D. Paneque, G. Madejski +305
We present coordinated multiwavelength observations of the bright, nearby BL Lac object Mrk 421 taken in 2013 January-March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, V…
Long-duration gamma-ray emissions from 2007 and 2008 winter thunderstorms
H. Tsuchiya, T. Enoto, S. Yamada +8
The Gamma-Ray Observation of Winter THunderclouds (GROWTH) experiment, consisting of two radiation-detection subsystems, has been operating since 2006 on the premises of Kashiwazak…
Accretion geometry of the neutron star low mass X-ray binary Cyg X-2 from X-ray polarization measurements
R. Farinelli, S. Fabiani, J. Poutanen +92
We report spectro-polarimetric results of an observational campaign of the bright neutron star low-mass X-ray binary Cyg X-2 simultaneously observed by IXPE, NICER and INTEGRAL. Co…
IXPE Observations of the Blazar Mrk 501 in 2022: A Multiwavelength View
L. Lisalda, E. Gau, H. Krawczynski +157
The blazar Markarian 501 (Mrk 501) was observed on three occasions over a 4-month period between 2022 March and 2022 July with the Imaging X-ray Polarimetry Explorer (IXPE). In thi…
Property of LCP-GEM in Pure Dimethyl Ether at Low Pressure
Y. Takeuchi, T. Tamagawa, T. Kitaguchi +9
We present a systematic investigation of the gain properties of a gas electron multiplier (GEM) foil in pure dimethyl ether (DME) at low pressures. The GEM is made from copper- cla…