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The Chandra, Hubble Space Telescope, and VLA View of the Circumnuclear Extended Emission in the Narrow Emission Line Galaxy NGC 2110
Gallagher, Sarah C.; Lee, Julia C.; Kraft, Ralph P. +4 more
We present results from new Chandra, archival Hubble Space Telescope (HST), and VLA imaging observations of the circumnuclear extended emission in the nearby Type 2 Seyfert galaxy NGC 2110. We find resolved soft-band X-ray emission ~4" (~160 pc) north of the nucleus, which is spatially coincident with [O III] emission, but lies just beyond the nor…
Multiwavelength Observations of EXO 0748-676. II. Emission-Line Behavior
O'Brien, K.; King, A. R.; Nelemans, G. +6 more
We present optical and ultraviolet spectra, light curves, and Doppler tomograms of the low-mass X-ray binary EXO 0748-676. Using an extensive set of 15 emission-line tomograms, we show that, along with the usual emission from the stream and ``hot spot,'' there is extended nonaxisymmetric emission from the disk rim. Some of the emission and Hα and …
Lensing Magnification of Supernovae in the GOODS Fields
Goobar, A.; Mörtsell, E.; Lee, K. +3 more
Gravitational lensing of high-redshift supernovae is potentially an important source of uncertainty when cosmological parameters are being derived from the measured brightness of Type Ia supernovae, especially in deep surveys with scarce statistics. Photometric and spectroscopic measurements of foreground galaxies along the lines of sight of 33 su…
Pseudobulges in the Disk Galaxies NGC 7690 and NGC 4593
Kormendy, John; Knapen, Johan H.; Cornell, Mark E. +2 more
We present Ks-band surface photometry of NGC 7690 (Hubble type Sab) and NGC 4593 (SBb). We find that, in both galaxies, a major part of the ``bulge'' is as flat as the disk and has approximately the same color as the inner disk. In other words, the ``bulges'' of these galaxies have disklike properties. We conclude that these are example…
Footpoint Motion of the Continuum Emission in the 2002 September 30 White-Light Flare
Ding, M. D.; Chen, Q. R.
We present observations of the 2002 September 30 white-light flare, in which the optical continuum emission near the Hα line is enhanced by ~10%. The continuum emission exhibits a close temporal and spatial coincidence with the hard X-ray (HXR) footpoint observed by RHESSI. We find a systematic motion of the flare footpoint seen in the continuum e…
INTEGRAL and RXTE Observations of Centaurus A
Rothschild, Richard E.; Staubert, Rüdiger; Wilms, Jörn +6 more
INTEGRAL and RXTE performed three simultaneous observations of the nearby radio galaxy Centaurus A in 2003 March, 2004 January, and 2004 February with the goals of investigating the geometry and emission processes via the spectral/temporal variability of the X-ray/low-energy gamma-ray flux, and intercalibration of the INTEGRAL instruments with res…
Capella Corona Revisited: A Combined View from XMM-Newton RGS and Chandra HETGS and LETGS
Sako, M.; Kahn, S. M.; Gupta, R. +2 more
We present a combined analysis of the X-ray emission of the Capella corona obtained with XMM-Newton RGS and Chandra HETGS and LETGS. An improved atomic line database and a new differential emission measure (DEM) deconvolution method are developed for this purpose. Our new atomic database is based on the Astrophysical Plasma Emission Database and i…
Long-lived Solar Neutron Emission in Comparison with Electron-produced Radiation in the 2005 September 7 Solar Flare
Tanaka, Y. T.; Yoshikawa, I.; Mukai, T. +23 more
Strong signals of neutral emissions were detected in association with a solar flare that occurred on 2005 September 7. They were produced by both relativistic ions and electrons. In particular, relativistic neutrons were observed with the solar neutron telescopes (SNTs) located at Mount Chacaltaya in Bolivia and Mount Sierra Negra in Mexico and wi…
The Evolution of Rest-Frame K-Band Properties of Early-Type Galaxies from z = 1 to the Present1,
Rix, H. -W.; van der Wel, A.; Illingworth, G. D. +3 more
We measure the evolution of the rest-frame K-band fundamental plane from z=1 to the present by using IRAC imaging of a sample of early-type galaxies in the Chandra Deep Field-South at z~1 with accurately measured dynamical masses. We find that M/LK evolves as Δln(M/LK)=(-1.18+/-0.10)z, which is slower than in the B band [Δln(…
Hidden Trigger for the Giant Starburst Arc in M83?
Mediavilla, Evencio; Díaz, Rubén J.; Dottori, Horacio +3 more
The huge star formation events that occur at some galactic centers do not provide enough clues as to their origin, since the morphological signatures of the triggering mechanism are smeared out in the timescale of a few orbital revolutions of the galaxy core. Our high spatial resolution three-dimensional near-infrared spectroscopy for the first ti…