相关论文: Discovery of 40.5 ks Hard X-ray Pulse-Phase Modula…
We present RXTE observations of the soft gamma--ray repeater SGR 1900+14 taken September 4-18, 1996, nearly 2 years before the 1998 active period of the source. The pulsar period (P) of 5.1558199 +/- 0.0000029 s and period derivative (Pdot)…
The magnetic deformation of magnetars is affected by their internal magnetic fields, which are generally difficult to be measured directly through observations. In this work, the periodic pulse-phase modulations in the hard X-ray emissions…
We present timing and broad-band spectral studies of the high mass X-ray binary pulsar 4U 1909+07 using data from Suzaku observation during 2010 November 2-3. The pulse period of the pulsar is estimated to be 604.11+/-0.14 s. Pulsations are…
The soft-gamma repeater SGR 1900+14 became active again on June 1998 after a long period of quiescence; it remained at a low state of activity until August 1998, when it emitted a series of extraordinarily intense outbursts. We have…
AXPs and SGRs constitute a special population of young neutron stars, which are thought to be magnetars, i.e., neutron stars with super-strong magnetic fields (10^14 - 10^15 G). Assuming that AXPs and SGRs accrete matter from a fallback…
A few years after its discovery as a magnetar, SGR J1935+2154 started a new burst-active phase on 2020 April 27, accompanied by a large enhancement of its X-ray persistent emission. Radio single bursts were detected during this activation,…
We report on simultaneous NuSTAR and XMM-Newton observations of the magnetar 1E 1048.1$-$5937 obtained in July 2013, along with Rossi X-ray Timing Explorer (RXTE) data for the same source obtained from December 2002 through March 2012. The…
The present study aims to reinforce the evidence for the ~9 s pulsation in the gamma-ray binary LS 5039, derived with a Suzaku observation in 2007 and that with NuSTAR in 2016 (Yoneda et al 2000). Through a reanalysis of the NuSTAR data…
We present an analysis of the neutron star High Mass X-ray Binary (HMXB) 4U 1909+07 mainly based on Suzaku data. We extend the pulse period evolution, which behaves in a random-walk like manner, indicative of direct wind accretion. Studying…
We present detailed spectral and timing studies using a NuSTAR observation of GX 1+4 in October 2015 during an intermediate intensity state. The measured spin period of 176.778 s is found to be one of the highest values since its discovery.…
We report on the timing and spectral analysis of two Suzaku observations with different flux levels of the high-mass X-ray binary KS 1947+300 during its 2013 outburst. In agreement with simultaneous NuSTAR observations, the continuum is…
Anomalous X-ray pulsars (AXPs) are thought to be magnetars, which are neutron stars with ultra strong magnetic field of $10^{14}$-- $10^{15}$ G. Their energy spectra below $\sim$10 keV are modeled well by two components consisting of a…
A pointed observation on the galactic high-mass X-ray binary 4U 0114+65 was carried out with BeppoSAX in order to compare the X-ray spectral and timing characteristics observed by this satellite over the broadest range of energies ever…
The magnetar SGR J1745-2900 located in the vicinity of the supermassive black hole Sgr A$^{\star}$ was detected during its X-ray outburst with the Swifht/XRT telescope in April 2013. For several months after its detection the source was…
We present the results of a detailed study of the high mass X-ray binary 2S 0114+650 made with the pointed instruments onboard the Rossi X-ray Timing Explorer. The spectral and temporal behaviour of this source was examined over the pulse,…
We present results from spectral and temporal analyses of Suzaku and RXTE observations of the high mass X-ray binary LMC X-4. Using the full 13 years of available RXTE/ASM data, we apply the ANOVA and Lomb normalized Periodogram methods to…
The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing hard X-ray mission in orbit and operates in the 3-79 keV range. NuSTAR's sensitivity is roughly two orders of magnitude better than previous missions in this energy…
We represent noise strength analysis of Anomalous X-Ray Pulsars (AXPs) 4U 0142+61, 1RXS J170849.9-400910, 1E 1841-045, 1E 2259+586 and Soft Gamma Repeaters (SGRs) SGR J1833-0832, SWIFT J1822.3-1606 and SWIFT J1834.9-0846 together with the…
The accretion-powered pulsar Her X-1 was observed with Suzaku twice in its main-on state, on 2005 October 5-6 and 2006 March 29-30, for a net exposure of 30.5 ks and 34.4 ks, respectively. In the 2005 and 2006 observations, the source was…
Using 2.5 Ms of data obtained by the INTEGRAL satellite in 2003-2004, we discovered persistent hard X-ray emission from the soft gamma-ray repeater SGR 1900+14. Its 20-100 keV spectrum is well described by a steep power law with photon…