Search Publications
Dynamically Excited Outer Solar System Objects in the Hubble Space Telescope Archive
Fuentes, Cesar I.; Holman, Matthew J.; Trilling, David E.
We present the faintest mid-ecliptic latitude survey in the second part of Hubble Space Telescope archival search for outer solar system bodies. We report the discovery of 28 new trans-Neptunian objects and one small centaur (R ~ 2 km) in the band 5°-20° off the ecliptic. The inclination distribution of these excited objects is consistent with the…
The Nature of Star Formation at 24 µm in the Group Environment at 0.3 <~ z <~ 0.55
Parker, L. C.; Wilman, D. J.; Mulchaey, J. S. +7 more
Galaxy star formation rates (SFRs) are sensitive to the local environment; for example, the high-density regions at the cores of dense clusters are known to suppress star formation. It has been suggested that galaxy transformation occurs largely in groups, which are the intermediate step in density between field and cluster environments. In this p…
The Hot Components of AM CVn Helium Cataclysmics
Sion, Edward M.; Godon, Patrick; Linnell, Albert P. +1 more
We present the results of a multi-component synthetic spectral analysis of the archival far-ultraviolet spectra of the hot components of several AM CVn double degenerate interacting binaries with known distances from trigonometric parallaxes. Our analysis was carried out using the code BINSYN, which takes into account the donor companion star, the…
Properties and Expected Number Counts of Active Galactic Nuclei and Their Hosts in the Far-infrared
Ballantyne, D. R.; Draper, A. R.
Telescopes like Herschel and the Atacama Large Millimeter/submillimeter Array (ALMA) are creating new opportunities to study sources in the far-infrared (FIR), a wavelength region dominated by cold dust emission. Probing cold dust in active galaxies allows for study of the star formation history of active galactic nucleus (AGN) hosts. The FIR is a…
Line Shape Effects on Intensity Measurements of Solar Features: Brightness Correction to SOHO MDI Continuum Images
Ermolli, I.; Del Moro, D.; Tritschler, A. +4 more
Continuum intensity observations obtained with the Michelson Doppler Imager (MDI) on board the SOHO mission provide long time series of filtergrams that are ideal for studying the evolution of large-scale phenomena in the solar atmosphere and their dependence on solar activity. These filtergrams, however, are not taken in a pure continuum spectral…
Time Evolution of the Reverse Shock in SN 1006
Long, Knox S.; Fesen, Robert A.; Winkler, P. Frank +1 more
The Schweizer-Middleditch star, located behind the SN 1006 remnant and near its center in projection, provides the opportunity to study cold, expanding ejecta within the SN 1006 shell through UV absorption. Especially notable is an extremely sharp red edge to the Si II 1260 Å feature, which stems from the fastest moving ejecta on the far side of t…
Sub-THz and Hα Activity during the Preflare and Main Phases of a GOES Class M2 Event
White, Stephen M.; Kaufmann, Pierre; Marcon, Rogério +8 more
Radio and optical observations of the evolution of flare-associated phenomena have shown an initial and rapid burst at 0.4 THz only followed subsequently by a localized chromospheric heating producing an Hα brightening with later heating of the whole active region. A major instability occurred several minutes later producing one impulsive burst at…
Deriving the Physical Parameters of a Solar Ejection with an Isotropic Magnetohydrodynamic Evolutionary Model
Vourlidas, Angelos; Stenborg, Guillermo; Berdichevsky, Daniel B.
The time-space evolution of a ~50° wide coronal mass ejection (CME) on 2007 May 21 is followed remotely with the Solar Terrestrial Relations Observatory heliospheric imager HI-1, and measured in situ near Venus by the MESSENGER and Venus-Express spacecraft. The paper compares the observations of the CME structure with a simple, analytical magnetoh…
An Analytical Model for the Coronal Component of Major Solar Energetic Particle Events
Valtonen, Eino; Cho, Kyung-Suk; Kocharov, Leon
We formulate an analytical model of the coronal-phase acceleration observed in the beginning of major solar energetic particle (SEP) events, before the main-phase acceleration associated with coronal mass ejections (CMEs) in solar wind. The model is driven and constrained by the broadband observations of SEPs and CMEs, in particular SEP data from …
Evidence for Solar Frequency Dependence on Sunspot Type
Basu, Sarbani; Baldner, Charles S.; Bogart, Richard S.
High-degree solar mode frequencies as measured by ring diagrams are known to change in the presence of the strong magnetic fields found in active regions. We examine these changes in frequency for a large sample of active regions analyzed with data from the Michelson Doppler Imager on board the Solar and Heliospheric Observatory spacecraft, spanni…