Search Publications
Diffusion of Solar Magnetic Elements up to Supergranular Spatial and Temporal Scales
Gošić, M.; Orozco Suárez, D.; Bellot Rubio, L. +3 more
The study of spatial and temporal scales on which small magnetic structures (magnetic elements) are organized in the quiet Sun may be approached by determining how they are transported on the solar photosphere by convective motions. The process involved is diffusion. Taking advantage of Hinode high spatial resolution magnetograms of a quiet-Sun re…
NuSTAR Observations of Magnetar 1E 1841-045
An, Hongjun; Hailey, Charles J.; Kaspi, Victoria M. +18 more
We report new spectral and temporal observations of the magnetar 1E 1841-045 in the Kes 73 supernova remnant obtained with the Nuclear Spectroscopic Telescope Array. Combined with new Swift and archival XMM-Newton and Chandra observations, the phase-averaged spectrum is well characterized by a blackbody plus double power law, in agreement with pre…
Deep Chandra Observations of A2199: The Interplay between Merger-induced Gas Motions and Nuclear Outbursts in a Cool Core Cluster
Fabian, Andrew C.; Sanders, Jeremy S.; Churazov, Eugene +9 more
We present new Chandra observations of A2199 that show evidence of gas sloshing due to a minor merger, as well as impacts of the radio source, 3C 338, hosted by the central galaxy, NGC 6166, on the intracluster gas. The new data are consistent with previous evidence of a Mach ~= 1.46 shock 100'' from the cluster center, although there is still no …
On the Radii of Brown Dwarfs Measured with AKARI Near-infrared Spectroscopy
Murakami, H.; Yamamura, I.; Sorahana, S.
We derive the radii of 16 brown dwarfs observed by AKARI using their parallaxes and the ratios of observed to model fluxes. We find that the brown dwarf radius ranges between 0.64-1.13 RJ with an average radius of 0.83 RJ . We find a trend in the relation between radii and T eff; the radius is at a minimum at T
The Ultraluminous GRB 110918A
Zhang, X.; Sbarufatti, B.; Hurley, K. +29 more
GRB 110918A is the brightest long gamma-ray burst (GRB) detected by Konus-WIND during its almost 19 yr of continuous observations and the most luminous GRB ever observed since the beginning of the cosmological era in 1997. We report on the final Interplanetary Network localization of this event and its detailed multiwavelength study with a number …
Overlying Extreme-ultraviolet Arcades Preventing Eruption of a Filament Observed by AIA/SDO
Zhang, Jun; Chen, Huadong; Ma, Suli
Using the multi-wavelength data from the Atmospheric Imaging Assembly/Solar Dynamic Observatory (AIA/SDO) and the Sun Earth Connection Coronal and Heliospheric Investigation/Solar Terrestrial Relations Observatory (SECCHI/STEREO), we report a failed filament eruption in NOAA AR 11339 on 2011 November 3. The eruption was associated with an X1.9 fla…
Metallicity Effect on Low-mass X-Ray Binary Formation in Globular Clusters
Ivanova, N.; Fabbiano, G.; Sivakoff, G. R. +4 more
We present comprehensive observational results of the metallicity effect on the fraction of globular clusters (GCs) that contain low-mass X-ray binaries (LMXB), by utilizing all available data obtained with Chandra for LMXBs and Hubble Space Telescope Advanced Camera for Surveys (ACS) for GCs. Our primary sample consists of old elliptical galaxies…
Ionized Outflows from Compact Steep Spectrum Sources
Shih, Hsin-Yi; Stockton, Alan; Kewley, Lisa
Massive outflows are known to exist, in the form of extended emission-line regions (EELRs), around about one-third of powerful FR II radio sources. We investigate the origin of these EELRs by studying the emission-line regions around compact-steep-spectrum (CSS) radio galaxies that are younger (103-105 yr old) versions of the…
Extinction and Dust Geometry in M83 H II Regions: An Hubble Space Telescope/WFC3 Study
Blair, William P.; Calzetti, Daniela; Chandar, Rupali +7 more
We present Hubble Space Telescope/WFC3 narrow-band imaging of the starburst galaxy M83 targeting the hydrogen recombination lines (Hβ, Hα, and Paβ), which we use to investigate the dust extinction in the H II regions. We derive extinction maps with 6 pc spatial resolution from two combinations of hydrogen lines (Hα/Hβ and Hα/Paβ), and show that th…
Shape Evolution of Massive Early-type Galaxies: Confirmation of Increased Disk Prevalence at z > 1
van der Wel, Arjen; Zibetti, Stefano; Rix, Hans-Walter +4 more
We use high-resolution K-band VLT/HAWK-I imaging over 0.25 deg2 to study the structural evolution of massive early-type galaxies since z ~ 2. Mass-selected samples, complete down to log(M/M ⊙) ~ 10.7 such that "typical" (L*) galaxies are included at all redshifts, are drawn from pre-existing photometric redshift surveys. We t…