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Laboratory astrophysics and atomic physics using the NASA/GSFC microcalorimeter spectrometers at the LLNL electron beam ion trap and radiation properties facility
Boyce, K. R.; Kilbourne, C. A.; Porter, F. S. +10 more
The 32 pixel laboratory microcalorimeter spectrometer built by the NASA/Goddard Space Flight Center (GSFC) is now an integral part of the spectroscopy suite used routinely by the electron beam ion trap and radiative properties group at the Lawrence Livermore National Laboratory. The second generation laboratory instrument, dubbed the XRS/EBIT, is …
XMM-Newton Detection of the Rare Fanaroff-Riley Type II Broad Absorption Line Quasar FIRST J101614.3+520916
White, Richard L.; Gregg, Michael D.; Lacy, Mark +5 more
We have detected FIRST J101614.3+520916 with the XMM-Newton X-ray observatory. FIRST J101614.3+520916, one of the most extreme radio-loud, broad absorption line (BAL) quasars so far discovered, is also a Fanaroff-Riley type II radio source. We find that, compared to its estimated intrinsic X-ray flux, the observed X-rays are likely suppressed and …
The MEGA Project for Medium Energy Gamma-ray Astronomy
Hartmann, D. H.; Ajello, M.; Di Cocco, G. +22 more
The Medium Energy Gamma-ray Astronomy (MEGA) telescope concept will soon be proposed as a MIDEX mission. This mission would enable a sensitive all-sky survey of the medium-energy gamma-ray sky (0.4 50 MeV) and bridge the huge sensitivity gap between the COMPTEL and OSSE experiments on the Compton Gamma Ray Observatory and the visionary Advanced Co…
Absolute Magnitudes of Be Stars Based on Hipparcos Parallaxes
Zhang, P.; Chen, P. S.; Liu, C. Q.
The absolute visual magnitudes of 457 Be stars are determined from Hipparcos parallaxes, subsequently the mean absolute visual magnitudes of Be stars for luminosity classes III, IV and V are obtained. The new Mv calibration is compared with existing calibrations. It is found that Be stars are generally brighter than B stars of the corresponding sp…
A systematic search of highly variable X-ray sources with the XMM-Newton serendipitous survey
Yuan, Weimin; Komossa, Stefanie; Osborne, Julian P. +1 more
We describe an ongoing programme to search for X-ray sources with long-term, large amplitude X-ray variability. The method is to compare the X-ray sources from the XMM-Newton Serendipitous Survey with those from the previous ROSAT pointed observations and the ROSAT All-sky Survey. The work is largely motivated by the recent discovery of a new type…
Two candidate homologous CMEs on 2002 May 22
Cheng, J. X.; Chen, P. F.; Fang, C.
Two coronal mass ejections (CMEs) occurred on 2002 May 22, originating from the same active region, AR 9948. Multi-wavelength data are collected in order to clarify the relationship between the CMEs, the associated flares and filament eruptions, and some other magnetic activities, which is of great importance to understand the mechanism of each ph…
Comment on ``Interplanetary shocks unconnected with earthbound coronal mass ejections'' by T. A. Howard and S. J. Tappin
Gopalswamy, Nat; Akiyama, Sachiko; Yashiro, Seiji +1 more
Abstract Available from http://www.agu.org
XMM-Newton Observations of X-Ray Emission from Jupiter
Branduardi-Raymont, G.; Soria, R.; Ramsay, G. +6 more
XMM-Newton observations of Jupiter show prominent soft X-ray emission from the auroral spots and, albeit at a lower intensity, from the equatorial regions. While the spectra of the auroral X-rays can be modeled with a superposition of unresolved emission lines, including most prominently those of highly ionized oxygen, Jupiter's equatorial ‘disk’ …
Stellar population of the central regions of NGC 5128
Tikhonov, N. A.; Galazutdinova, O. A.; Hagen-Thorn, V. A. +1 more
We present the results of stellar photometry in eight fields of NGC 5128 (Cen A), a candidate polar-ring galaxy, obtained by reducing images from the Hubble Space Telescope archive. In all cases, the color-magnitude diagrams reached the red-giant region, and the distance to the galaxy was determined from the position of the tip of the red-giant br…
Strong magnetic asymmetries in weakly interacting spirals
Ehle, M.; Beck, R.; Chyży, K. T.
We investigate the influence of cluster environment on the structure and evolution of magnetic fields and the interstellar medium in the Virgo cluster spiral NGC 4254. Our sensitive interferometric (VLA) and single dish (Effelsberg) radio polarimetric observations reveal several magnetic spiral arms displaced from optical ones. However, the southe…