Search Publications
Observations and Magnetic Field Modeling of a Solar Polar Crown Prominence
van Ballegooijen, Adriaan; Su, Yingna
We present observations and magnetic field modeling of the large polar crown prominence that erupted on 2010 December 6. Combination of Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA) and STEREO_Behind/EUVI allows us to see the fine structures of this prominence both at the limb and on the disk. We focus on the structures and d…
A Statistical Study of Solar Electron Events over One Solar Cycle
Krucker, Säm; Lin, R. P.; Mason, Glenn M. +1 more
We survey the statistical properties of 1191 solar electron events observed by the WIND 3DP instrument from <1 keV to gsim300 keV for a solar cycle (1995 through 2005). After taking into account times of high background, the corrected occurrence frequency of solar electron events versus peak flux exhibits a power-law distribution over three ord…
Reconstructing the Near-infrared Background Fluctuations from Known Galaxy Populations Using Multiband Measurements of Luminosity Functions
Ricotti, Massimo; Kashlinsky, Alexander; Helgason, Kari
We model fluctuations in the cosmic infrared background (CIB) arising from known galaxy populations using 233 measured UV, optical, and near-IR luminosity functions (LFs) from a variety of surveys spanning a wide range of redshifts. We compare best-fit Schechter parameters across the literature and find clear indication of evolution with redshift.…
Radio and X-Ray Observations of SN 2006jd: Another Strongly Interacting Type IIn Supernova
Chandra, Poonam; Fransson, Claes; Chevalier, Roger A. +5 more
We report four years of radio and X-ray monitoring of the Type IIn supernova SN 2006jd at radio wavelengths with the Very Large Array, Giant Metrewave Radio Telescope, and Expanded Very Large Array; at X-ray wavelengths with Chandra, XMM-Newton, and Swift-XRT. We assume that the radio and X-ray emitting particles are produced by shock interaction …
Outer-disk Populations in NGC 7793: Evidence for Stellar Radial Migration
Holwerda, Benne W.; Radburn-Smith, David J.; de Jong, Roelof S. +8 more
We analyzed the radial surface brightness profile of the spiral galaxy NGC 7793 using HST/ACS images from the GHOSTS survey and a new HST/WFC3 image across the disk break. We used the photometry of resolved stars to select distinct populations covering a wide range of stellar ages. We found breaks in the radial profiles of all stellar populations …
An Observed Link between Active Galactic Nuclei and Violent Disk Instabilities in High-redshift Galaxies
Dickinson, Mark; Daddi, Emanuele; Juneau, Stéphanie +7 more
We provide evidence for a correlation between the presence of giant clumps and the occurrence of active galactic nuclei (AGNs) in disk galaxies. Giant clumps of 108-109 M ⊙ arise from violent gravitational instability in gas-rich galaxies, and it has been proposed that this instability could feed supermassive black…
Spitzer Evidence for a Late-heavy Bombardment and the Formation of Ureilites in η Corvi at ~1 Gyr
Manoj, P.; Sitko, M. L.; Watson, D. M. +7 more
We have analyzed Spitzer and NASA/IRTF 2-35 µm spectra of the warm, ~350 K circumstellar dust around the nearby MS star η Corvi (F2V, 1.4 ± 0.3 Gyr). The spectra show clear evidence for warm, water- and carbon-rich dust at ~3 AU from the central star, in the system's terrestrial habitability zone. Spectral features due to ultra-primitive com…
Multiwavelength Variations of 3C 454.3 during the 2010 November to 2011 January Outburst
Gurwell, Mark A.; Grupe, Dirk; Agudo, Iván +6 more
We present multiwavelength data of the blazar 3C 454.3 obtained during an extremely bright outburst from 2010 November through 2011 January. These include flux density measurements with the Herschel Space Observatory at five submillimeter-wave and far-infrared bands, the Fermi Large Area Telescope at γ-ray energies, Swift at X-ray, ultraviolet (UV…
Classification of X-Ray Sources in the XMM-Newton Serendipitous Source Catalog
Lin, Dacheng; Webb, Natalie A.; Barret, Didier
We carry out classification of 4330 X-ray sources in the 2XMMi-DR3 catalog. They are selected under the requirement of being a point source with multiple XMM-Newton observations and at least one detection with the signal-to-noise ratio larger than 20. For about one-third of them we are able to obtain reliable source types from the literature. They…
Red and Dead: The Progenitor of SN 2012aw in M95
Sollerman, J.; Inserra, C.; Smartt, S. J. +17 more
Core-collapse supernovae (SNe) are the spectacular finale to massive stellar evolution. In this Letter, we identify a progenitor for the nearby core-collapse SN 2012aw in both ground-based near-infrared and space-based optical pre-explosion imaging. The SN itself appears to be a normal Type II Plateau event, reaching a bolometric luminosity of 10<…