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The Jet and Circumnuclear Environment of 3C 293
O'Dea, Christopher P.; Axon, David J.; Sparks, William B. +5 more
We present new HST NIR polarimetry, broadband and narrowband imaging, and MERLIN 4.5 GHz multifrequency synthesis radio imaging of 3C 293, a unique radio galaxy whose host is an obvious merger remnant, in an exceptionally underdense region of space. We have discovered NIR, optical, and UV synchrotron emission from the jet. In the optical, the jet …
Oxygen Abundances in the Milky Way Using X-Ray Absorption Measurements toward Galaxy Clusters
Mushotzky, R. F.; Baumgartner, W. H.
We present measurements of the oxygen abundance of the Milky Way's ISM by observing the K-shell X-ray photoionization edge toward galaxy clusters. This effect is most easily observed toward objects with Galactic columns (nH) of a few times 1021 cm-2. We measure X-ray column densities toward 11 clusters and find tha…
Coronal Emission Measures and Abundances for Moderately Active K Dwarfs Observed by Chandra
Wood, Brian E.; Linsky, Jeffrey L.
We have used Chandra to resolve the nearby 70 Oph (K0 V+K5 V) and 36 Oph (K1 V+K1 V) binary systems for the first time in X-rays. The LETG/HRC-S spectra of all four of these stars are presented and compared with an archival LETG spectrum of another moderately active K dwarf, ɛ Eri. Coronal densities are estimated from O VII line ratios and emissio…
Chemical Enrichment of the Complex Hot ISM of the Antennae Galaxies. II. Physical Properties of the Hot Gas and Supernova Feedback
Zezas, A.; Raymond, J. C.; King, A. R. +5 more
We investigate the physical properties of the interstellar medium (ISM) in the merging pair of galaxies known as the Antennae (NGC 4038/4039), using the deep co-added ~411 ks Chandra ACIS-S data set. The method of analysis and some of the main results from the spectral analysis, such as metal abundances and their variations from ~0.2 to ~20-30 tim…
The Magnetic Field Strength in the Wall of the Local Bubble toward l, b ~ 300°, 0°
Andersson, B. -G.; Potter, S. B.
We present polarization measurements in the region around l, b = 300°, 0°, toward stars with well-determined distances, primarily in the range 40-200 pc. We argue that these observations trace polarization caused by dust in the wall of the Local Bubble (LB). Using a Chandrasekhar-Fermi analysis, we derive a plane-of-the-sky magnetic field strength…
Chandra and Hubble Space Telescope Study of the Globular Cluster NGC 288
Anderson, Scott F.; Kong, Albert K. H.; Verbunt, Frank +5 more
We report on the Chandra X-Ray Observatory observations of the globular cluster NGC 288. We detect four X-ray sources within the core radius and seven additional sources within the half-mass radius down to a limiting luminosity of LX=7×1030 ergs s-1 (assuming cluster membership) in the 0.3-7 keV band. We also obser…
Observations of Flux Rope Formation in the Outer Corona
Sheeley, N. R., Jr.; Wang, Y. -M.
In previous studies employing the Large Angle and Spectrometric Coronagraph (LASCO), we identified a class of white-light ejections that separate into incoming and outgoing components at distances of ~3-5 Rsolar from Sun center. These events, of which up to several per month are observed during high solar activity, are generally precede…
Evolution of the Reverse Shock Emission from SNR 1987A
Pun, C. S. J.; Smith, Nathan; Garnavich, Peter +13 more
We present new (2004 July) G750L and G140L Space Telescope Imaging Spectrograph (STIS) data of the Hα and Lyα emission from supernova remnant (SNR) 1987A. With the aid of earlier data, from 1997 October to 2002 October, we track the local evolution of Lyα emission and both the local and global evolution of Hα emission. The most recent observations…
Observation of Small-Scale Structure Using Sextupole Lensing
Irwin, John; Shmakova, Marina
Gravitational lensing by foreground halos with masses as small as 1010 Msolar can induce observable second-order shape distortions in background galaxy images in addition to the well-known elliptical shape distortion produced by first-order shear. Furthermore, the orientation of the second-order distortions is correlated with…
Variability Study of Seyfert 2 Galaxies with XMM-Newton
Awaki, Hisamitsu; Leighly, Karen M.; Murakami, Hirokatsu +1 more
We present the results of timing analysis of XMM-Newton observations of Seyfert 2 galaxies in order to search for differences in the mean properties of Seyfert 1 galaxies and Seyfert 2 galaxies. We selected 13 Seyfert 2 galaxies from the XMM-Newton archive that have hard X-ray components in their spectra and calculated the excess variance (σ2…