Search Publications
Investigating the Nuclear Obscuration in Two Types of Seyfert 2 Galaxies
Shu, X. W.; Wang, J. X.; Jiang, P. +2 more
We build a large sample of Seyfert 2 galaxies (Sy2s) with both optical spectropolarimetric and X-ray data available, in which 29 of the Sy2s have a detection of polarized broad emission lines (PBLs) and 25 do not. We find that for luminous Sy2s with L[OIII>1041 ergs s-1, sources with PBLs have smaller X-ray abso…
Probing the Formation of Low-Mass X-Ray Binaries in Globular Clusters and the Field
Kundu, Arunav; Zepf, Stephen E.; Maccarone, Thomas J.
We present an analysis of LMXBs and GCs in five early-type galaxies using Chandra X-ray and HST optical data. Of the 186 LMXBs within the optical fields of view, 71 are in GCs, confirming that LMXBs are formed particularly efficiently in clusters due to dynamical interactions. However, there is no statistically significant correlation between the …
Spitzer Space Telescope Observations of Kepler's Supernova Remnant: A Detailed Look at the Circumstellar Dust Component
Blair, William P.; Reynolds, Stephen P.; Ghavamian, Parviz +4 more
We present 3.6-160 µm infrared images of Kepler's supernova remnant (SN 1604) obtained with the IRAC and MIPS instruments on the Spitzer Space Telescope. We also present MIPS SED low-resolution spectra in the 55-95 µm region. The observed emission in the MIPS 24 µm band shows the entire shell. Emission in the MIPS 70 µm and…
Dependence of Galaxy Structure on Rest-Frame Wavelength and Galaxy Type
Conselice, Christopher J.; Windhorst, Rogier A.; Jansen, Rolf A. +1 more
We present a quantitative analysis of the morphologies for 199 nearby galaxies as parameterized with measurements of the concentration, asymmetry, and clumpiness (CAS) parameters at wavelengths from 0.15 to 0.85 µm. We find that these CAS parameters depend on both galaxy type and the wavelength of observation. As such, we use them to obtain …
Magnetic Field Strength in the Solar Corona from Type II Band Splitting
Cho, K. -S.; Moon, Y. -J.; Gary, D. E. +2 more
The phenomenon of band splitting in type II bursts can be a unique diagnostic for the magnetic field in the corona, which is, however, inevitably sensitive to the ambient density. We apply this diagnostic to the CME-flare event on 2004 August 18, for which we are able to locate the propagation of the type II burst and determine the ambient coronal…
Relativistic Iron K Emission and Absorption in the Seyfert 1.9 Galaxy MCG -5-23-16
Ptak, A.; Nandra, K.; Turner, T. J. +9 more
We present the results of the simultaneous deep XMM-Newton and Chandra observations of the bright Seyfert 1.9 galaxy MCG -5-23-16, which is thought to have one of the best known examples of a relativistically broadened iron Kα line. The time-averaged spectral analysis shows that the iron K-shell complex is best modeled with an unresolved narrow em…
Determination of the Coronal Magnetic Field from Hot-Loop Oscillations Observed by SUMER and SXT
Qiu, Jiong; Innes, Davina E.; Wang, Tongjiang
We apply a new method to determine the magnetic field in coronal loops, using observations of coronal loop oscillations. We analyze seven Doppler-shift oscillation events detected by SUMER in the hot flare line Fe XIX to obtain the oscillation periods of these events. The geometry, temperature, and electron density of the oscillating loops are mea…
The DEEP2 Galaxy Redshift Survey: AEGIS Observations of a Dual AGN at z = 0.7
Barmby, P.; Ivison, R. J.; Weiner, Benjamin J. +15 more
We present evidence of a dual active galactic nucleus (AGN) within an early-type galaxy at z=0.709 in the extended Groth strip. The galaxy lies on the red sequence, with absolute magnitude MB=-21.0 (AB, with h=0.7) and rest-frame color U-B=1.38. Its optical spectrum shows strong, double-peaked [O III] emission lines and weak Hβ emission…
Precise Timing of the X-ray Pulsar 1E 1207.4-5209: A Steady Neutron Star Weakly Magnetized at Birth
Gotthelf, E. V.; Halpern, J. P.
We analyze all X-ray timing data on 1E 1207.4-5209 in supernova remnant PKS 1209-51/52 gathered from 1993-2005 and find a highly stable rotation with P=424.130749(4) ms and P˙=(6.6+/-9.0)×10-17 (1 σ errors). This refutes previous claims of large timing irregularities in these data. In the dipole spin-down formalism, the 2 σ upper limit …
Coronal and Interplanetary Propagation of CME/Shocks from Radio, In Situ and White-Light Observations
Kaiser, M. L.; Bougeret, J. -L.; Reiner, M. J.
The kinematics of CMEs are well characterized to 32 Rsolar by height-time measurements from existing space-based and ground-based coronagraphs. Although there has been long-standing, but indirect, evidence that CMEs can exhibit significant deceleration as they propagate from Sun to Earth, the interplanetary kinematics of CMEs are not pr…