Search Publications
Kinematic Signatures of Bulges Correlate with Bulge Morphologies and Sérsic Index
Bender, Ralf; Drory, Niv; Fisher, David B. +3 more
We use the Marcario Low Resolution Spectrograph at the Hobby-Eberly Telescope to study the kinematics of pseudobulges and classical bulges in the nearby universe. We present major axis rotational velocities, velocity dispersions, and h 3 and h 4 moments derived from high-resolution (σinst ≈ 39 km s-1) sp…
IDCS J1433.2+3306: An Infrared-selected Galaxy Cluster at z = 1.89
Dey, Arjun; Gonzalez, Anthony H.; Stanford, S. A. +6 more
We report the discovery of an IR-selected galaxy cluster in the IRAC Distant Cluster Survey (IDCS). New data from the Hubble Space Telescope spectroscopically confirm IDCS J1433.2+3306 at z = 1.89 with robust spectroscopic redshifts for seven members, two of which are based on the 4000 Å break. Detected emission lines such as [O II] and Hβ indicat…
Evidence of Wave Damping at Low Heights in a Polar Coronal Hole
Hahn, M.; Savin, D. W.; Landi, E.
We have measured the widths of spectral lines from a polar coronal hole using the Extreme Ultraviolet Imaging Spectrometer on board Hinode. Polar coronal holes are regions of open magnetic field and the source of the fast solar wind. We find that the line widths decrease at relatively low heights. Previous observations have attributed such decreas…
A Young Massive Stellar Population around the Intermediate-mass Black Hole ESO 243-49 HLX-1
Maccarone, T. J.; Knigge, C.; Farrell, S. A. +9 more
We present Hubble Space Telescope and simultaneous Swift X-ray Telescope observations of the strongest candidate intermediate-mass black hole (IMBH) ESO 243-49 HLX-1. Fitting the spectral energy distribution from X-ray to near-infrared wavelengths showed that the broadband spectrum is not consistent with simple and irradiated disk models, but is w…
3D-HST Grism Spectroscopy of a Gravitationally Lensed, Low-metallicity Starburst Galaxy at z = 1.847
Schmidt, Kasper B.; van Dokkum, Pieter G.; Franx, Marijn +17 more
We present Hubble Space Telescope (HST) imaging and spectroscopy of the gravitational lens SL2SJ02176-0513, a cusp arc at z = 1.847. The UV continuum of the lensed galaxy is very blue, which is seemingly at odds with its redder optical colors. The 3D-HST WFC3/G141 near-infrared spectrum of the lens reveals the source of this discrepancy to be extr…
Polar Field Reversal Observations with Hinode
Ishikawa, R.; Tsuneta, S.; Orozco Suárez, D. +3 more
We have been monitoring yearly variation in the Sun's polar magnetic fields with the Solar Optical Telescope aboard Hinode to record their evolution and expected reversal near the solar maximum. All magnetic patches in the magnetic flux maps are automatically identified to obtain the number density and magnetic flux density as a function of the to…
Large-scale Motions in the Perseus Galaxy Cluster
Simionescu, A.; Fabian, A. C.; Allen, S. W. +6 more
By combining large-scale mosaics of ROSAT PSPC, XMM-Newton, and Suzaku X-ray observations, we present evidence for large-scale motions in the intracluster medium of the nearby, X-ray bright Perseus Cluster. These motions are suggested by several alternating and interleaved X-ray bright, low-temperature, low-entropy arcs located along the east-west…
Instantaneous Starburst of the Massive Clusters Westerlund 1 and NGC 3603 YC
Henning, Thomas; Da Rio, Nicola; Gennaro, Mario +9 more
We present a new method to determine the age spread of resolved stellar populations in a starburst cluster. The method relies on a two-step process. In the first step, kinematic members of the cluster are identified based on multi-epoch astrometric monitoring. In the second step, a Bayesian analysis is carried out, comparing the observed photometr…
Herschel/HIFI Discovery of HCl+ in the Interstellar Medium
Falgarone, E.; Godard, B.; Teyssier, D. +12 more
The radical ion HCl+, a key intermediate in the chlorine chemistry of the interstellar gas, has been identified for the first time in the interstellar medium with the Herschel Space Observatory's Heterodyne Instrument for the Far-Infrared. The ground-state rotational transition of H35Cl+, 2Π3/2
Binaries among Debris Disk Stars
Zuckerman, B.; Rodriguez, David R.
We have gathered a sample of 112 main-sequence stars with known debris disks. We collected published information and performed adaptive optics observations at Lick Observatory to determine if these debris disks are associated with binary or multiple stars. We discovered a previously unknown M-star companion to HD 1051 at a projected separation of …