Search Publications
A Herschel Survey of Cold Dust in Disks around Brown Dwarfs and Low-mass Stars
Pascucci, Ilaria; Henning, Thomas; Ménard, François +6 more
We report the complete photometric results from our Herschel study which is the first comprehensive program to search for far-infrared emission from cold dust around young brown dwarfs (BDs). We surveyed 50 fields containing 51 known or suspected BDs and very low mass stars that have evidence of circumstellar disks based on Spitzer photometry and/…
Luminous and High Stellar Mass Candidate Galaxies at z ≈ 8 Discovered in the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey
Papovich, Casey; Finkelstein, Steven L.; Dickinson, Mark +26 more
One key goal of the Hubble Space Telescope Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey is to track galaxy evolution back to z ≈ 8. Its two-tiered "wide and deep" strategy bridges significant gaps in existing near-infrared surveys. Here we report on z ≈ 8 galaxy candidates selected as F105W-band dropouts in one of its deep fields…
The Unusual Temporal and Spectral Evolution of SN2011ht. II. Peculiar Type IIn or Impostor?
Humphreys, Roberta M.; Davidson, Kris; Pogge, R. W. +4 more
SN2011ht has been described both as a true supernova (SN) and as an impostor. In this paper, we conclude that it does not match some basic expectations for a core-collapse event. We discuss SN2011ht's spectral evolution from a hot dense wind to a cool dense wind, followed by the post-plateau appearance of a faster low density wind during a rapid d…
Luminous Satellites. II. Spatial Distribution, Luminosity Function, and Cosmic Evolution
Treu, T.; Auger, M. W.; Fassnacht, C. D. +3 more
We infer the normalization and the radial and angular distributions of the number density of satellites of massive galaxies (log10[M*h/M ⊙] > 10.5) between redshifts 0.1 and 0.8 as a function of host stellar mass, redshift, morphology, and satellite luminosity. Exploiting the depth and resolution of the COSMOS H…
The Relationship between the Sudden Change of the Lorentz Force and the Magnitude of Associated Flares
Liu, Chang; Wang, Haimin; Wang, Shuo
The rapid and irreversible change of photospheric magnetic fields associated with flares has been confirmed by many recent studies. These studies showed that the photospheric magnetic fields respond to coronal field restructuring and turn to a more horizontal state near the magnetic polarity inversion line (PIL) after eruptions. Recent theoretical…
Evidence for Type Ia Supernova Diversity from Ultraviolet Observations with the Hubble Space Telescope
Van Dyk, Schuyler D.; Filippenko, Alexei V.; Maoz, Dan +93 more
We present ultraviolet (UV) spectroscopy and photometry of four Type Ia supernovae (SNe 2004dt, 2004ef, 2005M, and 2005cf) obtained with the UV prism of the Advanced Camera for Surveys on the Hubble Space Telescope. This data set provides unique spectral time series down to 2000 Å. Significant diversity is seen in the near-maximum-light spectra (~…
Through the Looking Glass: Bright, Highly Magnified Galaxy Candidates at z ~ 7 behind A1703
Ford, H. C.; Zheng, W.; Zitrin, A. +7 more
We report the discovery of seven strongly lensed Lyman-break galaxy (LBG) candidates at z ~ 7 detected in Hubble Space Telescope Wide Field Camera 3 (WFC3) imaging of A1703. The brightest candidate, called A1703-zD1, has an observed (lensed) magnitude of 24.0 AB (26σ) in the WFC3/IR F160W band, making it 0.2 mag brighter than the z 850-…
Near-infrared Imaging of a z = 6.42 Quasar Host Galaxy with the Hubble Space Telescope Wide Field Camera 3
Ryan, R. E.; Koekemoer, A. M.; Fan, X. +12 more
We report on deep near-infrared F125W (J) and F160W (H) Hubble Space Telescope Wide Field Camera 3 images of the z = 6.42 quasar J1148+5251 to attempt to detect rest-frame near-ultraviolet emission from the host galaxy. These observations included contemporaneous observations of a nearby star of similar near-infrared colors to measure temporal var…
Double Bow Shocks around Young, Runaway Red Supergiants: Application to Betelgeuse
Langer, Norbert; Neilson, Hilding R.; Mackey, Jonathan +2 more
A significant fraction of massive stars are moving supersonically through the interstellar medium (ISM), either due to disruption of a binary system or ejection from their parent star cluster. The interaction of their wind with the ISM produces a bow shock. In late evolutionary stages these stars may undergo rapid transitions from red to blue and …
Guiding Nonlinear Force-free Modeling Using Coronal Observations: First Results Using a Quasi-Grad-Rubin Scheme
Schrijver, C. J.; Wheatland, M. S.; Malanushenko, A. +2 more
At present, many models of the coronal magnetic field rely on photospheric vector magnetograms, but these data have been shown to be problematic as the sole boundary information for nonlinear force-free field extrapolations. Magnetic fields in the corona manifest themselves in high-energy images (X-rays and EUV) in the shapes of coronal loops, pro…