Search Publications
High-Resolution Spectroscopy of FU Orionis Stars
Herbig, G. H.; Duemmler, R.; Petrov, P. P.
High-resolution spectroscopy was obtained of the FU orionis stars FU Ori and V1057 Cyg between 1995 and 2002 with the SOFIN spectrograph at the Nordic Optical Telescope and with HIRES at Keck I. During these years FU Ori remained about 1 mag (in B) below its 1938-39 maximum brightness, but V1057 Cyg (B~10.5 at peak in 1970-1971) faded from about 1…
Discovery of Early Optical Emission from GRB 021211
Peterson, B. A.; Price, P. A.; Harrison, F. A. +11 more
We report our discovery and early-time optical, near-infrared, and radio wavelength follow-up observations of the afterglow of the gamma-ray burst GRB 021211. Our optical observations, beginning 21 minutes after the burst trigger, demonstrate that the early afterglow of this burst is roughly 3 mag fainter than the afterglow of GRB 990123 at simila…
Low-Redshift Damped Lyα Galaxies toward the Quasars B2 0827+243, PKS 0952+179, PKS 1127-145, and PKS 1629+120
Turnshek, David A.; Rao, Sandhya M.; Bergeron, Jacqueline +3 more
We present optical and near-infrared ground-based imaging results on four low-redshift damped Lyα (DLA) galaxies. The corresponding DLA systems were discovered in our Hubble Space Telescope spectroscopic surveys for DLA lines in known strong Mg II absorption-line systems toward the quasars B2 0827+243 (zDLA=0.525), PKS 0952+179 (zD…
The Rotation of the Deep Solar Layers
Henney, C. J.; García, R. A.; Corbard, T. +3 more
From the analysis of low-order GOLF+MDI sectoral modes (l<=3, 6<=n<=15, |m|=l) and LOWL data (l>3), we derive the radial rotation profile by assuming no latitudinal dependence in the solar core. These low-order acoustic modes contain the most statistically significant information about the rotation of the deepest solar layers and shoul…
The Assembly of Massive Galaxies from Near-Infrared Observations of the Hubble Deep Field-South
Fontana, A.; Vanzella, E.; Cristiani, S. +7 more
We use a deep KAB<=25 galaxy sample in the Hubble Deep Field-South to trace the evolution of the cosmological stellar mass density from z~=0.5 to z~=3. We find clear evidence for a decrease of the average stellar mass density at high redshift, 2<=z<=3.5, that is 15+25-5% of the local value, 2 times higher …
Hubble Space Telescope Images of Submillimeter Sources: Large Irregular Galaxies at High Redshift
Chapman, S. C.; Conselice, C.; Yan, H. +2 more
We present new Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) high-resolution optical imaging of a sample of 13 submillimeter luminous galaxies for which the optical emission has been pinpointed either through radio 1.4 GHz or millimeter interferometry. We find a predominance of irregular and complex morphologies in the sample,…
A New Method for Estimating Widths, Velocities, and Source Location of Halo Coronal Mass Ejections
Gopalswamy, N.; Yashiro, S.; Michałek, G.
It is well known that coronagraphic observations of halo coronal mass ejections (CMEs) are subject to projection effects. Viewing in the plane of the sky does not allow us to determine the crucial parameters that define the geoeffectiveness of CMEs, such as the space speed, width, or source location. Assuming that halo CMEs have constant velocitie…
Kinematics of 10 Early-Type Galaxies from Hubble Space Telescope and Ground-based Spectroscopy
Filippenko, Alexei V.; Ho, Luis C.; Gebhardt, Karl +11 more
We present stellar kinematics for a sample of 10 early-type galaxies observed using the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope and the Modular Spectrograph on the MDM Observatory 2.4 m telescope. These observations are a part of an ongoing program to understand the coevolution of supermassive black holes and …
Evidence for a Major Merger Origin of High-Redshift Submillimeter Galaxies
Conselice, Christopher J.; Windhorst, Rogier A.; Chapman, Scott C.
Submillimeter-detected galaxies located at redshifts z>1 host a major fraction of the bolometric luminosity at high redshifts due to thermal emission from heated dust grains, yet the nature of these objects remains a mystery. The major problem in understanding their origin is whether the dust-heating mechanism is predominantly caused by star fo…
The DEEP Groth Strip Survey. IX. Evolution of the Fundamental Plane of Field Galaxies
Illingworth, Garth D.; Weiner, Benjamin; Gebhardt, Karl +8 more
Fundamental plane studies provide an excellent means of understanding the evolutionary history of early-type galaxies. Using the Low Resolution Imaging Spectrograph on the Keck Telescope, we obtained internal stellar kinematic information for 36 field galaxies in the Groth Strip, 21 early-type and 15 disk galaxies. Their redshifts range from 0.3 t…