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The Relation between EIT Waves and Solar Flares
Chen, P. F.
In order to determine whether EIT waves are generated by coronal mass ejections (CMEs) or pressure pulses in solar flares, 14 non-CME-associated energetic flares, which should possess strong pressure pulses in their loops, are studied. They are selected near solar minimum, as this favors the detection of EIT waves. It is found that none of these f…
A Hubble Space Telescope Archival Survey of Feathers in Spiral Galaxies
Ostriker, Eve C.; La Vigne, Misty A.; Vogel, Stuart N.
We present a survey of spiral arm extinction substructures referred to as feathers in 223 spiral galaxies using Hubble Space Telescope WFPC2 images. The sample includes all galaxies in the RC3 catalog with cz<5000 km s-1, BT<15, i<60deg, and types Sa-Sd with well-exposed broadband WFPC2 images. The detecti…
Black Hole Mass of the Ultraluminous X-Ray Source M82 X-1
Dewangan, Gulab C.; Griffiths, Richard E.; Titarchuk, Lev
We report the first clear evidence for the simultaneous presence of a low-frequency break and a QPO in the fluctuation power spectrum of a well-known ultraluminous X-ray source (ULX) in M82 using long XMM-Newton observations. The break occurs at a frequency of 34.2+6-3 mHz. The QPO has a centroid at νQPO=114.3+/-1.…
Low-Mass X-Ray Binaries in Six Elliptical Galaxies: Connection to Globular Clusters
Lee, Myung Gyoon; Fabbiano, Giuseppina; Geisler, Doug +4 more
We present a systematic study of the low-mass X-ray binary (LMXB) populations of six elliptical galaxies, aimed at investigating the detected LMXB-globular cluster (GC) connection. We utilize Chandra archival data to identify X-ray point sources and HST archival data supplemented by ground observations to identify 6173 GCs. After screening and cro…
Enhanced Abundances in Three Large-Diameter Mixed-Morphology Supernova Remnants
Slane, P. O.; Lazendic, J. S.
We present an X-ray study of three mixed-morphology (MM) supernova remnants (SNRs)-HB 21, CTB 1, and HB 3-using archival ASCA and ROSAT data. These data are complemented by archival Chandra X-Ray Observatory data for CTB 1 and XMM-Newton X-Ray Observatory data for HB 3. The spectra from HB 21 and HB 3 are well described with a single-temperature t…
Current Sheet Evolution in the Aftermath of a CME Event
Raymond, J. C.; Bemporad, A.; Poletto, G. +4 more
We report on SOHO UVCS observations of the coronal restructuring following a coronal mass ejection (CME) on 2002 November 26, at the time of a SOHO-Ulysses quadrature campaign. Starting about 1.5 hr after a CME in the northwest quadrant, UVCS began taking spectra at 1.7 Rsolar, covering emission from both cool and hot plasma. Observatio…
The Excitation of Extended Red Emission: New Constraints on Its Carrier from Hubble Space Telescope Observations of NGC 7023
Gordon, Karl D.; Sell, Paul H.; Witt, Adolf N. +3 more
The carrier of the dust-associated photoluminescence process causing ERE in many dusty interstellar environments remains unidentified. Several competing models are more or less able to match the observed broad, unstructured ERE band. We now constrain the character of the ERE carrier further by determining the wavelengths of the radiation that init…
SN 1987A after 18 Years: Mid-Infrared Gemini and Spitzer Observations of the Remnant
Kirshner, Robert P.; Arendt, Richard G.; Danziger, John +6 more
Using the Gemini South 8 m telescope, we obtained high-resolution 11.7 and 18.3 µm mid-IR images of SN 1987A on day 6526 since the explosion. All the emission arises from the equatorial ring. Nearly contemporaneous spectra obtained at 5-38 µm with the Spitzer Space Telescope show that this is thermal emission from silicate dust that co…
Clustering of Star-forming Galaxies Near a Radio Galaxy at z=5.2
Ford, H. C.; Demarco, R.; Infante, L. +39 more
We present HST ACS observations of the most distant radio galaxy known, TN J0924-2201 at z=5.2. This radio galaxy has six spectroscopically confirmed Lyα-emitting companion galaxies and appears to lie within an overdense region. The radio galaxy is marginally resolved in i775 and z850, showing continuum emission aligned with …
INTEGRAL IBIS Extragalactic Survey: Active Galactic Nuclei Selected at 20-100 keV
Walter, R.; Bird, A. J.; Ubertini, P. +10 more
Analysis of International Gamma-Ray Astrophysics Laboratory (INTEGRAL) Core Programme and public open-time observations performed up to 2005 April provides a sample of 62 active galactic nuclei in the 20-100 keV band above a flux limit of ~1.5×10-11 ergs cm-2 s-1. Most (42) of the sources in the sample are Seyfert …