Search Publications
The Puzzling Mutual Orbit of the Binary Trojan Asteroid (624) Hektor
Wong, M. H.; Berthier, J.; Kalas, P. +9 more
Asteroids with satellites are natural laboratories to constrain the formation and evolution of our solar system. The binary Trojan asteroid (624) Hektor is the only known Trojan asteroid to possess a small satellite. Based on W. M. Keck adaptive optics observations, we found a unique and stable orbital solution, which is uncommon in comparison to …
Explosive Events on a Subarcsecond Scale in IRIS Observations: A Case Study
Doyle, J. G.; Fu, Hui; Madjarska, Maria S. +3 more
We present a study of a typical explosive event (EE) at subarcsecond scale witnessed by strong non-Gaussian profiles with blue- and redshifted emission of up to 150 km s-1 seen in the transition region Si IV 1402.8 Å, and the chromospheric Mg II k 2796.4 Å and C II 1334.5 Å observed by the Interface Region Imaging Spectrograph (IRIS) at…
The Density and Mass of Unshocked Ejecta in Cassiopeia A through Low Frequency Radio Absorption
Rudnick, Lawrence; Perley, R. A.; DeLaney, Tracey +1 more
Characterizing the ejecta in young supernova remnants is a requisite step toward a better understanding of stellar evolution. In Cassiopeia A the density and total mass remaining in the unshocked ejecta are important parameters for modeling its explosion and subsequent evolution. Low frequency (<100 MHz) radio observations of sufficient angular…
Spectral Energy Distribution Fitting of HETDEX Pilot Survey Lyα Emitters in COSMOS and GOODS-N
Finkelstein, Steven L.; Schneider, Donald P.; Bridge, Joanna +15 more
We use broadband photometry extending from the rest-frame UV to the near-IR to fit the individual spectral energy distributions of 63 bright (L(Lyα) > 1043 erg s-1) Lyα emitting galaxies (LAEs) in the redshift range 1.9 < z < 3.6. We find that these LAEs are quite heterogeneous, with stellar masses that span over thr…
Radio Imaging of a Type IVM Radio Burst on the 14th of August 2010
Krucker, S.; Bain, H. M.; Saint-Hilaire, P. +1 more
Propagating coronal mass ejections (CMEs) are often accompanied by burst signatures in radio spectrogram data. We present Nançay Radioheliograph observations of a moving source of broadband radio emission, commonly referred to as a type IV radio burst (type IVM), which occurred in association with a CME on the 14th of August 2010. The event was we…
The Mass of the Central Black Hole in the Nearby Seyfert Galaxy NGC 5273
Bentz, Misty C.; Jones, Jeremy; Parks, J. Robert +9 more
We present the results of a reverberation-mapping program targeting NGC 5273, a nearby early-type galaxy with a broad-lined active galactic nucleus (AGN). Over the course of the monitoring program, NGC 5273 showed strong variability that allowed us to measure time delays in the responses of the broad optical recombination lines to changes in the c…
Lens Models of Herschel-selected Galaxies from High-resolution Near-IR Observations
Ivison, R. J.; Clements, D. L.; Scott, D. +39 more
We present Keck-Adaptive Optics and Hubble Space Telescope high resolution near-infrared (IR) imaging for 500 µm bright candidate lensing systems identified by the Herschel Multi-tiered Extragalactic Survey and Herschel Astrophysical Terahertz Large Area Survey. Out of 87 candidates with near-IR imaging, 15 (~17%) display clear near-IR lensi…
Bolometric and UV Light Curves of Core-collapse Supernovae
Brown, Peter J.; Pritchard, T. A.; Roming, P. W. A. +2 more
The Swift UV-Optical Telescope (UVOT) has been observing core-collapse supernovae (CCSNe) of all subtypes in the UV and optical since 2005. Here we present 50 CCSNe observed with the Swift UVOT, analyzing their UV properties and behavior. Where we have multiple UV detections in all three UV filters (λ c = 1928-2600 Å), we generate earl…
Type IIb Supernova SN 2011dh: Spectra and Photometry from the Ultraviolet to the Near-infrared
Foley, Ryan J.; Bieryla, Allyson; Berlind, Perry +26 more
We report spectroscopic and photometric observations of the Type IIb SN 2011dh obtained between 4 and 34 days after the estimated date of explosion (May 31.5 UT). The data cover a wide wavelength range from 2000 Å in the ultraviolet (UV) to 2.4 µm in the near-infrared (NIR). Optical spectra provide line profiles and velocity measurements of …
Stellar Metallicity of the Extended Disk and Distance of the Spiral Galaxy NGC 3621
Hosek, Matthew W., Jr.; Bresolin, Fabio; Kudritzki, Rolf-Peter +2 more
Low resolution (~4.5 Å) ESO VLT/FORS spectra of blue supergiant stars are analyzed to determine stellar metallicities (based on elements such as iron, titanium, and magnesium) in the extended disk of the spiral galaxy, NGC 3621. Mildly subsolar metallicity (-0.30 dex) is found for the outer objects beyond 7 kpc, independent of galactocentric radiu…