Search Publications
The Discovery of Oxygen Kα X-Ray Emission from the Rings of Saturn
Bhardwaj, Anil; Gladstone, G. Randall; Cravens, Thomas E. +3 more
Using the Advanced CCD Imaging Spectrometer (ACIS), the Chandra X-Ray Observatory observed the Saturnian system for one rotation of the planet (~37 ks) on 2004 January 20 and again on January 26-27. In this Letter we report the detection of X-ray emission from the rings of Saturn. The X-ray spectrum from the rings is dominated by emission in a nar…
The Nature of Blue Cores in Spheroids: A Possible Connection with Active Galactic Nuclei and Star Formation
Illingworth, Garth D.; Frye, Brenda; Infante, Leopoldo +9 more
We investigate the physical nature of blue cores in early-type galaxies through the first multiwavelength analysis of a serendipitously discovered field blue-nucleated spheroid in the background of the deep Hubble Space Telescope ACS/WFC griz multicolor observations of the cluster A1689. The resolved g-r, r-i, and i-z color maps reveal a prominent…
Discovery of Strong Lensing by an Elliptical Galaxy at z = 0.0345
Tonry, John; Blakeslee, John P.; Lucey, John R. +1 more
We have discovered strong gravitational lensing by the galaxy ESO 325-G004, in images obtained with the Advanced Camera for Surveys on the Hubble Space Telescope. The lens galaxy is a boxy group-dominant elliptical at z=0.0345, making this the closest known galaxy-scale lensing system. The lensed object is very blue (B-IC~1.1), and form…
All Coronal Loops Are the Same: Evidence to the Contrary
Schmelz, J. T.; Beene, J. E.; Nasraoui, K. +3 more
The 1998 April 20 spectral line data from the Coronal Diagnostic Spectrometer on the Solar and Heliospheric Observatory show a coronal loop on the solar limb. Our original analysis of these data showed that the plasma was multithermal, both along the length of the loop and along the line of sight. However, more recent results by other authors indi…
A Fresh View of Henize 2-10 with VLT NAOS-CONICA
Cabanac, Rémi A.; Vanzi, Leonardo; Sauvage, Marc
We present high-resolution observations of Henize 2-10 in Ks (2.2 µm), L' (3.8 µm), and M' (4.8 µm) bands. These allow us, for the first time, to track accurately the structures at the heart of the galaxy from the optical to the radio. All radio knots previously observed can now be associated with L'- and Ks…
The Halo, Hot Spots, and Jet/Cloud Interaction of PKS 2153-69
Young, A. J.; Heinz, S.; Wilson, A. S. +1 more
We report Chandra X-Ray Observatory and 1.4 GHz Australian Long Baseline Array (LBA) observations of the radio galaxy PKS 2153-69 and its environment. The Chandra image reveals a roughly spherical halo of hot gas extending out to 30 kpc around PKS 2153-69. Two depressions in the surface brightness of the X-ray halo correspond to the large-scale ra…
Far Ultraviolet Spectroscopic Explorer Observations of the Symbiotic Star AG Draconis
Young, P. R.; Dupree, A. K.; Espey, B. R. +2 more
Spectra of the bright symbiotic star AG Draconis (BD +67°922) in the wavelength range 905-1187 Å obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) are presented. The spectra show a number of narrow, nebular emission lines, together with a uniform continuum from the hot component of the system, and numerous interstellar absorption lin…
An X-Ray View of Weak-Line Radio Galaxies/LINERs
Gliozzi, Mario; Sambruna, Rita M.; Rinn, Alexander S.
We present X-ray observations of nine weak-line radio galaxies (WLRGs), optically classified as confirmed or possible LINERs. The data were taken from the Chandra, XMM-Newton, and BeppoSAX archives. The Chandra images typically show complex X-ray morphologies, with hard (2-10 keV) point sources embedded in diffuse soft (0.3-2.0 keV) emission in al…
Kinetic Helicity Density in Solar Subsurface Layers and Flare Activity of Active Regions
Howe, R.; Komm, R.; Hill, F. +2 more
We search for a relation between subsurface flows below active regions and flare events occurring in those regions. For this purpose, we use a ring-diagram analysis to determine the subsurface flows from high-resolution Global Oscillation Network Group (GONG) and Michelson Doppler Imager (MDI) data and derive the kinetic helicity as a measure of t…
Late-Time X-Ray, UV, and Optical Monitoring of Supernova 1979C
Van Dyk, Schuyler D.; Petre, Robert; Rudie, Gwen C. +8 more
We present results from observations of supernova (SN) 1979C with the Newton X-Ray Multi-Mirror (XMM-Newton) mission in X-rays and in UV, archival X-ray, and Hubble Space Telescope (HST) data, and follow-up ground-based optical imaging. The XMM-Newton MOS spectrum shows the best-fit two-temperature thermal plasma emission characteristics of both t…