Search Publications
Deconvolution of Images from BLAST 2005: Insight into the K3-50 and IC 5146 Star-forming Regions
France, Kevin; Devlin, Mark J.; Halpern, Mark +26 more
We present an implementation of the iterative flux-conserving Lucy-Richardson (L-R) deconvolution method of image restoration for maps produced by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST). Compared to the direct Fourier transform method of deconvolution, the L-R operation restores images with better-controlled background no…
Oxidizing Proto-atmosphere on Titan: Constraint from N2 Formation by Impact Shock
Mousis, Olivier; Sekine, Yasuhito; Matsui, Takafumi +1 more
Titan is the only satellite that possesses a thick atmosphere, composed mainly of N2 and CH4. However, its origin and evolution remain largely unknown. Knowledge of the acquirement of a N2 atmosphere on Titan would provide insights into nitrogen evolution in planetary atmospheres as well as the formation of satelli…
A Search for Young Stars in the S0 Galaxies of a Super-group at z = 0.37
Tran, Kim-Vy H.; Moustakas, John; Gonzalez, Anthony H. +3 more
We analyze Galaxy Evolution Explorer UV data for a system of four gravitationally bound groups at z = 0.37, SG1120, which is destined to merge into a Coma-mass cluster by z = 0, to study how galaxy properties may change during cluster assembly. Of the 38 visually classified S0 galaxies, with masses ranging from log (M *)[M sun
Redshifts, Widths, and Radiances of Spectral Lines Emitted by the Solar Transition Region
Doschek, G. A.; Dammasch, I. E.; Feldman, U.
A long-standing problem in understanding the physics of the transition region has been the ubiquitous redshifts of transition region ultraviolet spectral lines relative to chromospheric emission lines, a result known since the Skylab era. Extended spectral scans performed for various regions of the solar disk by the Solar Ultraviolet Measurements …
The mm-colors of a Young Binary Disk System in the Orion Nebula Cluster
Testi, L.; Williams, J. P.; Ricci, L. +2 more
We present new Expanded Very Large Array (EVLA) continuum observations at 7 mm of the 253-1536 binary disk system in the Orion Nebula Cluster. The measured fluxes were combined with data in the submillimeter to derive the millimeter spectral index of each individual disk component. We show how these observations can be used to test the models of d…
The Infrared Jet in 3C 31
Jones, Christine; Kraft, Ralph P.; Forman, William R. +5 more
We report the detection of infrared emission from the jet of the nearby Fanaroff-Riley type I radio galaxy 3C 31. The jet was detected with the IRAC instrument on Spitzer at 4.5 µm, 5.8 µm, and 8.0 µm out to 30'' (13 kpc) from the nucleus. We measure radio, infrared, optical, and X-ray fluxes in three regions along the jet determ…
Coronal Jets, Magnetic Topologies, and the Production of Interplanetary Electron Streams
van Driel-Gesztelyi, L.; Owen, C. J.; Li, C. +2 more
We investigate the acceleration source of the impulsive solar energetic particle (SEP) events on 2007 January 24. Combining the in situ electron measurements and remote-sensing solar observations, as well as the calculated magnetic fields obtained from a potential-field source-surface model, we demonstrate that the jets associated with the hard X-…
Fast Timing Analysis of Cygnus X-1 Using the SPectrometer on the International Gamma-Ray Astrophysics Laboratory
Jourdain, Elisabeth; Roques, Jean-Pierre; Cabanac, Clément
We report for the first time the high-frequency analysis of Cyg X-1 up to hard X-ray using the spectrometer on International Gamma-Ray Astrophysics Laboratory (INTEGRAL). After analyzing the possible contribution from the background, and using the INTEGRAL archive from 2005 March to 2008 May, power density spectra were obtained up to 130 keV. Firs…
The Suzaku View of the Disk-Jet Connection in the Low-excitation Radio Galaxy NGC 6251
Hardcastle, M. J.; Croston, J. H.; Gandhi, P. +4 more
We present results from an 87 ks Suzaku observation of the canonical low-excitation radio galaxy (LERG) NGC 6251. We have previously suggested that LERGs violate conventional active galactic nucleus unification schemes: they may lack an obscuring torus and are likely to accrete in a radiatively inefficient manner, with almost all of the energy rel…
On Asymmetry of Magnetic Helicity in Emerging Active Regions: High-resolution Observations
Alexander, David; Démoulin, Pascal; Zhu, Chunming +1 more
We employ the DAVE (differential affine velocity estimator) tracking technique on a time series of Michelson Doppler Imager (MDI)/1 minute high spatial resolution line-of-sight magnetograms to measure the photospheric flow velocity for three newly emerging bipolar active regions (ARs). We separately calculate the magnetic helicity injection rate o…