Publications (22)
New multiwavelength observations of the Of?p star CPD -28 2561
S. Hubrig, M. Schöller, A. Kholtygin +7
A rather strong mean longitudinal magnetic field of the order of a few hundred Gauss was detected a few years ago in the Of?p star CPD -28 2561 using FORS2 low-resolution spectropo…
High-resolution X-ray spectroscopy with XRISM/Resolve reveals super-Solar abundance ratios in Virgo/M87
J. Martin, A. Simionescu, F. Mernier +26
The chemical composition of the intracluster medium (ICM) provides key insights into the enrichment history of galaxy clusters. However, high-resolution abundance measurements with…
Dynamics of AGN feedback in the X-ray bright East and Southwest arms of M87, mapped by XRISM
A. Simionescu, C. Kilbourne, H. R. Russell +24
As the central galaxy in the nearest cluster, M87 provides the best spatial resolution for disentangling the complex interactions between AGN jets and the surrounding environment.…
Swift X-ray and UV monitoring of the Classical Nova V458 Vul (Nova Vul 2007)
J. -U. Ness, J. J. Drake, A. P. Beardmore +18
We describe the highly variable X-ray and UV emission of V458 Vul (Nova Vul 2007), observed by Swift between 1 and 422 days after outburst. Initially bright only in the UV, V458 Vu…
X-ray Eclipse Diagnosis of the Evolving Mass Loss in the Recurrent Nova U Scorpii 2010
D. Takei, J. J. Drake, M. Tsujimoto +4
We report the Suzaku detection of the earliest X-ray eclipse seen in the recurrent nova U Scorpii 2010. A target-of-opportunity observation 15 days after the outburst found a 27+/-…
Spin and Relativistic Phenomena Around Black Holes
L. Brenneman, J. M. Miller, K. Nandra +13
Since the seminal work of Penrose (1969) and Blandford & Znajek (1977), it has been realized that black hole spin may be an important energy source in astrophysics. The radio-loud/…
Detection of a Rare Supersoft Outburst Event during a Suzaku Observation of 1E0102.2-7219
D. Takei, M. Tsujimoto, S. Kitamoto +4
We report the detection of a transient X-ray source toward the Small Magellanic Cloud (SMC) using the X-ray Imaging Spectrometer (XIS) onboard the Suzaku telescope. The source was…
Stellar-Mass Black Holes and Their Progenitors
J. M. Miller, P. Uttley, K. Nandra +14
If a black hole has a low spin value, it must double its mass to reach a high spin parameter. Although this is easily accomplished through mergers or accretion in the case of super…
X-ray Study of Rekindled Accretion in the Classical Nova V2491 Cygni
D. Takei, J. -U. Ness, M. Tsujimoto +5
We conducted an X-ray spectroscopic study of the classical nova V2491 Cygni using our target-of-opportunity observation data with the Suzaku and XMM-Newton satellites as well as ar…
A XRISM/Resolve view of the dynamics in the hot gaseous atmosphere of M87
XRISM Collaboration, M. Audard, H. Awaki +138
The XRISM/Resolve microcalorimeter directly measured the gas velocities in the core of the Virgo Cluster, the closest example of AGN feedback in a cluster. This proximity allows us…
Suzaku Observation of AXP 1E 1841-045 in SNR Kes 73
M. Morii, S. Kitamoto, N. Shibazaki +7
Anomalous X-ray pulsars (AXPs) are thought to be magnetars, which are neutron stars with ultra strong magnetic field of -- G. Their energy spectra below 10…
Suzaku Detection of Super-hard X-ray Emission from the Classical Nova V2491 Cygni
D. Takei, M. Tsujimoto, S. Kitamoto +4
We report the detection of super-hard (>10 keV) X-ray emission extending up to 70 keV from the classical nova V2491 Cygni using the Suzaku observatory. We conducted two ~20 ks targ…
Broad band X-ray spectroscopy of A0535+262 with SUZAKU
S. Naik, T. Dotani, Y. Terada +9
The transient X-ray binary pulsar A0535+262 was observed with Suzaku on 2005 September 14 when the source was in the declining phase of the August-September minor outburst. The ~10…
X-ray Development of the Classical Nova V2672 Ophiuchi with Suzaku
D. Takei, M. Tsujimoto, J. J. Drake +1
We report the Suzaku detection of a rapid flare-like X-ray flux amplification early in the development of the classical nova V2672 Ophiuchi. Two target-of-opportunity ~25 ks X-ray…
ASTRO-H White Paper - Accreting Pulsars, Magnetars, and Related Sources
S. Kitamoto, T. Enoto, S. Safi-Harb +18
As the endpoints of massive star evolution, neutron stars are enigmatic celestial objects characterized by extremely dense and exotic nuclear matter, magnetospheres with positrons…
Fundamental Accretion and Ejection Astrophysics
J. M. Miller, M. Nowak, K. Nandra +11
Disk accretion may be the fundamental astrophysical process. Stars and planets form through the accretion of gas in a disk. Black holes and galaxies co-evolve through efficient dis…
Complex outburst behaviour from the black-hole candidate 4U 1630-47
E. Kuulkers, A. N. Parmar, S. Kitamoto +2
We present data from different epochs in 1978, 1987-1991 and 1996 from the black-hole candidate 4U1630-47. For the first time we present almost complete coverage of the outbursts w…
Wide band X-ray Imager (WXI) and Soft Gamma-ray Detector (SGD) for the NeXT Mission
T. Takahashi, A. Awaki, T. Dotani +25
The NeXT mission has been proposed to study high-energy non-thermal phenomena in the universe. The high-energy response of the super mirror will enable us to perform the first sens…
Long-term X-ray variability and state transition of GX 339-4
A. K. H. Kong, P. A. Charles, E. Kuulkers +1
With extensive monitoring data spanning over 30 years from Vela 5B, Ariel 5, Ginga, Compton Gamma Ray Observatory, Rossi X-ray Timing Explorer and BeppoSAX, we find evidence for lo…
Changes in the long term intensity variations in Cyg X-2 and LMC X-3
B. Paul, S. Kitamoto, F. Makino
We report the detection of changes in the long-term intensity variations in two X-ray binaries, Cyg X-2 and LMC X-3. In this work, we have used the long-term light curves obtained…
Energy Spectra and Normalized Power Spectral Densities of X-Ray Nova GS 2000+25
K. Terada, S. Kitamoto, H. Negoro +1
The X-ray energy spectra and Normalized Power Spectral Densities (NPSDs) of an X-ray nova, GS 2000+25, were investigated. The X-ray energy spectra of the source consist of two comp…
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…