Search Publications
The Properties and Prevalence of Galactic Outflows at z ~ 1 in the Extended Groth Strip
Martin, Crystal L.; Shapley, Alice E.; Coil, Alison L. +5 more
We investigate galactic-scale outflowing winds in 72 star-forming galaxies at z ~ 1 in the Extended Groth Strip. Galaxies were selected from the DEEP2 survey and follow-up LRIS spectroscopy was obtained covering Si II, C IV, Fe II, Mg II, and Mg I lines in the rest-frame ultraviolet. Using Galaxy Evolution Explorer (GALEX), Hubble Space Telescope …
CANDELS Observations of the Structural Properties of Cluster Galaxies at z = 1.62
Wuyts, S.; Ferguson, H. C.; Finkelstein, S. L. +25 more
We discuss the structural and morphological properties of galaxies in a z = 1.62 proto-cluster using near-IR imaging data from Hubble Space Telescope Wide Field Camera 3 data of the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS). The cluster galaxies exhibit a clear color-morphology relation: galaxies with colors of quiescent s…
Discovery of radio haloes and double relics in distant MACS galaxy clusters: clues to the efficiency of particle acceleration
Vazza, F.; Edge, A. C.; Bonafede, A. +6 more
We have performed 323 MHz observations with the Giant Metrewave Radio Telescope of the most promising candidates selected from the MACS catalogue. The aim of the work is to extend our knowledge of the radio halo and relic populations to z > 0.3, the epoch in which massive clusters are formed. In MACSJ1149.5+2223 and MACSJ1752.1+4440, we discove…
Not Dead Yet: Cool Circumgalactic Gas in the Halos of Early-type Galaxies
Tripp, Todd M.; Prochaska, J. Xavier; Sembach, Kenneth R. +10 more
We report new observations of circumgalactic gas in the halos of early-type galaxies (ETGs) obtained by the COS-Halos Survey with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. We find that detections of H I surrounding ETGs are typically as common and strong as around star-forming galaxies, implying that the total mass of ci…
Verifying Asteroseismically Determined Parameters of Kepler Stars Using Hipparcos Parallaxes: Self-consistent Stellar Properties and Distances
Christensen-Dalsgaard, J.; Weiss, A.; García, R. A. +24 more
Accurately determining the properties of stars is of prime importance for characterizing stellar populations in our Galaxy. The field of asteroseismology has been thought to be particularly successful in such an endeavor for stars in different evolutionary stages. However, to fully exploit its potential, robust methods for estimating stellar param…
A combined optical and X-ray study of unobscured type 1 active galactic nuclei - III. Broad-band SED properties
Done, Chris; Ward, Martin; Jin, Chichuan
In this third paper in a series of three, we present a detailed study of the broad-band spectral energy distribution (SED) of active galactic nuclei (AGNs) based on a nearby unobscured type 1 AGN sample. We perform a systematic cross-correlation study of several key parameters, i.e. Γ2-10 keV, L2-10 keV, Lbol/L
On the probability of occurrence of extreme space weather events
Riley, Pete
By virtue of their rarity, extreme space weather events, such as the Carrington event of 1859, are difficult to study, their rates of occurrence are difficult to estimate, and prediction of a specific future event is virtually impossible. Additionally, events may be extreme relative to one parameter but normal relative to others. In this study, we…
Temperature-pressure profile of the hot Jupiter HD 189733b from HST sodium observations: detection of upper atmospheric heating
Pont, F.; Lecavelier des Etangs, A.; Vidal-Madjar, A. +4 more
We present transmission spectra of the hot Jupiter HD 189733b taken with the Space Telescope Imaging Spectrograph (STIS) aboard Hubble Space Telescope (HST). The spectra cover the wavelength range 5808-6380 Å with a resolving power of R= 5000. We detect absorption from the Na I doublet within the exoplanet's atmosphere at the 9σ confidence level w…
The Initial Mass Function of the Orion Nebula Cluster across the H-burning Limit
Henning, T.; Robberto, M.; Da Rio, N. +2 more
We present a new census of the Orion Nebula Cluster over a large field of view (gsim 30' × 30'), significantly increasing the known population of stellar and substellar cluster members with precisely determined properties. We develop and exploit a technique to determine stellar effective temperatures from optical colors, nearly doubling the previo…
Chandra/HETGS Observations of the Brightest Flare Seen from Sgr A*
Miller, J. M.; Nowak, M. A.; Grosso, N. +10 more
Starting in 2012, we began an unprecedented observational program focused on the supermassive black hole in the center of our Galaxy, Sgr A*, utilizing the High Energy Transmission Grating Spectrometer (HETGS) instrument on the Chandra X-Ray Observatory. These observations will allow us to measure the quiescent X-ray spectra of Sgr A* for the firs…