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Chandra and ROSAT Observations of A194: Detection of an X-Ray Cavity and Mapping the Dynamics of the Cluster
Baum, Stefi A.; O'Dea, Christopher P.; Churazov, Eugene +6 more
Based on Chandra and ROSAT observations, we investigated the nearby poor cluster A194, which hosts two luminous radio galaxies, NGC 547 (3C 40B) and NGC 541 (3C 40A). We demonstrated the presence of a large X-ray cavity (r ~ 34 kpc) formed by the giant southern radio lobe arising from 3C 40B in NGC 547. The estimated age of the cavity is t = 7.9 ×…
Unveiling Extragalactic Star Formation Using Radio Recombination Lines: An Expanded Very Large Array Pilot Study with NGC 253
Johnson, Kelsey E.; Chomiuk, Laura; Pisano, D. J. +3 more
Radio recombination lines (RRLs) are powerful, extinction-free diagnostics of the ionized gas in young, star-forming regions. Unfortunately, these lines are difficult to detect in external galaxies. We present the results of Expanded Very Large Array (EVLA) observations of the RRL and radio continuum emission at 33 GHz from NGC 253, a nearby nucle…
The Remarkable γ-Ray Activity in the Gravitationally Lensed Blazar PKS 1830-211
Costa, E.; Barbiellini, G.; Longo, F. +34 more
We report the extraordinary γ-ray activity (E > 100 MeV) of the gravitationally lensed blazar PKS 1830-211 (z = 2.507) detected by AGILE between 2010 October and November. On October 14, the source experienced a factor of ~12 flux increase with respect to its average value and remained brightest at this flux level (~500 × 10-8 photon…
A Jet Model for the Broadband Spectrum Of the Seyfert 1 Galaxy NGC 4051
Miller, Jon M.; Markoff, Sera; Maitra, Dipankar +1 more
Recent radio very long baseline interferometry observations of the ~ parsec-scale nuclear region of the narrow line Seyfert 1 galaxy NGC 4051 hint toward the presence of outflowing plasma. From available literature we have collected high-quality, high-resolution broadband spectral energy distribution (SED) data of the nuclear region of NGC 4051 sp…
A High Spatial Resolution Study of the λ = 3 mm Continuum of Orion-KL
Friedel, D. N.; Widicus Weaver, S. L.
Recent interferometric observations have called into question the traditional view of the Orion-KL region, which displays one of the most well-defined cases of chemical differentiation in a star-forming region. Previous lower-resolution images of Orion-KL show emission signatures for oxygen-bearing organic molecules toward the Orion Compact Ridge …
X-Ray Warm Absorption and Emission in the Polar-scattered Seyfert 1 Galaxy Mrk 704
Dewangan, Gulab C.; Laha, Sibasish; Kembhavi, Ajit K.
We present a detailed study of the ionized environment of the Seyfert 1 galaxy Mrk 704 using medium- and high-resolution X-ray spectra obtained with a long XMM-Newton observation. The 0.3-10 keV continuum, well described by a power law (Γ ≈ 1.86) and two blackbodies (kT ≈ 0.085 and 0.22 keV), is found to be affected by a neutral partial covering a…
The 2006 Outburst of the Magnetar CXOU J164710.2 - 455216
Kaspi, Victoria M.; Woods, Peter M.; Gavriil, Fotis P. +1 more
We report on data obtained with the Chandra, XMM-Newton, Suzaku, and Swift X-ray observatories, following the 2006 outburst of the Anomalous X-ray Pulsar CXOU J164710.2-455216. Using a more complete and higher signal-to-noise data set, we find no evidence for the very large glitch and rapid exponential decay as was reported previously for this sou…
The UV-continuum Properties of Lyα-selected Galaxies at z = 6.5
Cowie, Lennox L.; Hu, Esther M.; Songaila, Antoinette
We report the first space-based very deep near-infrared continuum observations of a uniform sample of z = 6.5 galaxies with log(L(Lyα)) = 42.5-43 erg s-1 selected from narrowband line searches and with spectroscopically confirmed Lyα emission. The 1.4 µm Hubble Space Telescope WFC3 observations are deep enough (AB(1σ) = 28.75) to …
Spectroscopic Analysis of Interaction between an Extreme-ultraviolet Imaging Telescope Wave and a Coronal Upflow Region
Ding, M. D.; Chen, P. F.; Harra, L. K. +1 more
We report a spectroscopic analysis of an EUV Imaging Telescope (EIT) wave event that occurred in active region 11081 on 2010 June 12 and was associated with an M2.0 class flare. The wave propagated nearly circularly. The southeastern part of the wave front passed over an upflow region near a magnetic bipole. Using EUV Imaging Spectrometer raster o…
Strong Variable Ultraviolet Emission from Y Gem: Accretion Activity in an Asymptotic Giant Branch Star with a Binary Companion?
Gil de Paz, Armando; Neill, James D.; Sahai, Raghvendra +1 more
Binarity is believed to dramatically affect the history and geometry of mass loss in asymptotic giant branch (AGB) and post-AGB stars, but observational evidence of binarity is sorely lacking. As part of a project to look for hot binary companions to cool AGB stars using the Galaxy Evolution Explorer archive, we have discovered a late-M star, Y Ge…