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RX J1648.7+6109: Witnessing the Formation of a Massive Group/Poor Cluster and Its Brightest Galaxy
Mulchaey, John S.; Lubin, Lori M.; Jeltema, Tesla E.
Using deep Chandra and optical spectroscopic observations, we investigate an intriguing young massive group, RX J1648.7+6109, at z = 0.376, and we combine these observations with previous measurements to fit the scaling relations of intermediate-redshift groups and poor clusters. RX J1648 appears to be in an early stage of formation; while it foll…
XMM-Newton X-ray and optical monitor far UV observations of NGC 7070A and ESO 2400100 shell galaxies
Marino, A.; Trinchieri, G.; Rampazzo, R. +3 more
Context: Shell galaxies are considered to be the debris of recent accretion/merging episodes. Their high frequency in low density environments suggests that these episodes could drive the secular evolution of at least some fraction of the early-type galaxy population.
Aims: We present XMM-Newton X-ray observations of two shell galaxies, NGC 70…
The Cygnus region: A laboratory for nucleosynthesis
Martin, Pierrick; Knödlseder, Jürgen; Meynet, Georges
We have observed the Cygnus region in the gamma-ray decay lines of 26Al and 60Fe with the INTEGRAL/SPI spectrometer. A study of the morphology of the 1809 keV emission from 26Al suggests an emission region centered about the massive star cluster Cyg OB2, with a characteristic size between 6° and 9° or possibly high…
Predicted interplanetary shocks/particles at Mars compared with in-situ observations: An overview
McKenna-Lawlor, Susan M. P.
The biological and technological consequences of long-duration, solar-related, energetic particle radiation for manned/unmanned spacecraft warrant that consideration be given to providing reliable space weather predictions for future space missions to planet Mars. An account is, herein, provided of how the HAFv.2 numerical model was applied to pre…
Vertical Temperature Structures of the Solar Corona Derived with the Hinode X-Ray Telescope
Golub, Leon; Hara, Hirohisa; Shimojo, Masumi +12 more
We obtained temperature structures in faint coronal features above and near the solar limb with the X-Ray Telescope aboard the Hinode satellite by accurately correcting the scattered X-rays from surrounding bright regions with occulted images during the solar eclipses. Our analysis yields a polar coronal hole temperature of about 1.0MK and an emis…
A Search for Temperature and Density Variations in NGC 7027 with the Hubble Space Telescope
Bieging, John H.; Tielens, A. G. G. M.; Boley, Paul A. +1 more
We observed the young planetary nebula NGC 7027 with the HST Imaging Spectrograph (STIS) in long-slit mode at five slit positions along the major axis of the nebula, over the wavelength range from 3000 to ~10,000 Å. We used dereddened line ratios to determine line-of-sight average values for (1) He++ and He+ ionization fracti…
In situ spectroscopy of the solar corona
Li, B.; Fineschi, S.; Habbal, S. R. +1 more
Context: Future spacecraft missions, such as the proposed Solar Probe mission, will venture close to the Sun, allowing spectrometers measuring emission from heavy ions or neutrals in the solar wind to have radial lines of sight (LOS) pointing away from the Sun, or indeed in any direction other than sunwards.
Aims: We show that a radial LOS giv…
Multiwavelength Monitoring of the Dwarf Seyfert 1 Galaxy NGC 4395. IV. The Variable UV Absorption Lines
Laor, Ari; Baskin, Alexei
We report the detection of variable UV absorption lines in NGC 4395, based on UV observations with the HST STIS carried out in 2004 April and July as part of a reverberation-mapping campaign. Low-ionization lines of O I, N I, Si II, C II, and Fe II are present in the low-state spectra (2004 April) at a velocity vshift = - 250 km s-…
INTEGRAL observations of the SNR IC443 region
Bocchino, F.; Kretschmar, P.; Bykov, A. M. +3 more
IC433 is a supernova remnant (SNR) interacting with a molecular cloud. The field of IC443 also contains an unidentified gamma-ray source 3EG J0617 + 2238. Recent observations with XMM-Newton and Chandra have revealed a number of hard X-ray sources in the field of the extended SNR including a pulsar wind nebula and an enigmatic hard X-ray source in…
The radial gradient of galactic cosmic rays: Ulysses KET and ACE CRIS Measurements
Kunow, H.; Mewaldt, R. A.; Gieseler, J. +6 more
We study the spatial gradients of galactic cosmic rays in the inner heliosphere using data from the Kiel Electron Telescope (KET) aboard Ulysses and the Cosmic Ray Isotope Spectrometer (CRIS) aboard the Advanced Composition Explorer (ACE) for the time period from 1997 to 2007. This covers the solar minimum in the A>0-solar magnetic epoch, the s…