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IGR J16328-4726: A New Candidate Supergiant Fast X-ray Transient
Bird, A. J.; Fiocchi, M.; Ubertini, P. +4 more
The unidentified source IGR J16328-4726 was covered with INTEGRAL observations for a long period (~9.8 Ms) and was undetectable for most of the time while showing a very recurrent micro-activity with a duration from tens of minutes to several hours. We report the discovery of two strong outbursts started at 53420.65 MJD and 54859.99 MJD, respectiv…
A Suzaku X-ray Study of the Particle Acceleration Processes in the Relativistic Jet of Blazar Mrk 421
Baring, Matthew G.; Krawczynski, Henric; Garson, Alfred B., III
We report on the findings of a 364 ks observation of the BL LAC object Mrk 421 with the X-ray observatory Suzaku. The analysis in this paper uses fluxes and hardness ratios (HRs) in the broad energy range from 0.5 keV to 30 keV. During the course of the observation, the 0.5-30 keV flux decreased by a factor of ~2 and was accompanied by several lar…
XMM-Newton X-ray Observation of the High-magnetic-field Radio Pulsar PSR J1734-3333
Kramer, M.; Lyne, A. G.; Kaspi, V. M. +1 more
Using observations made with the XMM-Newton Observatory, we report the probable X-ray detection of the high-magnetic-field radio pulsar PSR J1734-3333. This pulsar has an inferred surface dipole magnetic field of B = 5.2 × 1013 G, just below that of one anomalous X-ray pulsar. We find that the pulsar has an absorbed 0.5-2.0 keV flux of …
Large-scale Soft X-ray Loops and Their Magnetic Chirality in Both Hemispheres
Zhang, Hongqi; Gao, Yu; Su, Jiangtao +3 more
The magnetic chirality in the solar atmosphere has been studied based on soft X-ray and magnetic field observations. It is found that some of the large-scale twisted soft X-ray loop systems occur for several months in the solar atmosphere, before the disappearance of the corresponding background large-scale magnetic field. This paper provides obse…
Gradual Inflation of Active-region Coronal Arcades Building up to Coronal Mass Ejections
Liu, Chang; Wang, Haimin; Liu, Rui +1 more
The pre-coronal mass ejection (pre-CME) structure is of great importance to understanding the origin of CMEs, which, however, has been largely unknown for CMEs originating from active regions. In this paper, we investigate this issue using the wavelet-enhanced EUV Imaging Telescope (EIT) observations combined with the Large Angle and Spectrometric…
Structure and Dynamics of Quiescent Filament Channels Observed by Hinode/XRT and STEREO/EUVI
Golub, Leon; van Ballegooijen, Adriaan; Su, Yingna
We present a study of the structure and dynamics of quiescent filament channels observed by Hinode/XRT and STEREO/EUVI at the solar minimum 23/24 from 2006 November to 2008 December. For 12 channels identified on the solar disk (Group I channels), we find that the morphology of the structure on the two sides of the channel is asymmetric in both X-…
Hinode Observation of Photospheric Magnetic Activities Triggering X-ray Microflares Around a Well-developed Sunspot
Kano, R.; Shimizu, T.; Tarbell, T. D.
Microflares, which are small energetic events in the solar corona, are an example of dynamical phenomena suitable for understanding energy release processes in the solar corona. We identified 55 microflares around a well-developed sunspot surrounded by a moat with high-cadence X-ray images from the Hinode X-ray Telescope, and searched for their ph…
Multiband Nonthermal Radiative Properties of HESS J1813-178
Fang, Jun; Zhang, Li
The source HESS J1813-178 was detected in a survey of the inner Galaxy in TeV γ-rays, and a composite supernova remnant (SNR) G12.8-0.0 was identified in the radio band to be associated with it. The pulsar wind nebula (PWN) embedded in the SNR is powered by an energetic pulsar PSR J1813-1749, which was recently discovered. Whether the TeV γ-rays o…
Measurements of Rapid Density Fluctuations in the Solar Wind
Bale, S. D.; Kellogg, P. J.; Malaspina, D. M. +1 more
The power spectrum of density fluctuations in the solar wind is inferred by tracking small timescale changes in the electron plasma frequency during periods of strong Langmuir wave activity. STEREO electric field waveform data are used to produce time profiles of plasma density from which the density power spectrum is derived. The power spectra ob…
The Accreting White Dwarf in SS Cygni Revealed
Blair, William P.; Sion, Edward M.; Godon, Patrick +1 more
We have carried out a combined Hubble Space Telescope (HST/GHRS) and Far Ultraviolet Spectroscopic Explorer (FUSE) analysis of the prototype dwarf nova SS Cygni during quiescence. The FUSE and HST spectra were obtained at comparable times after outburst and have matching flux levels where the two spectra overlap. In our synthetic spectral analysis…