Search Publications
The Structure of the Prototype Bipolar Protoplanetary Nebula CRL 2688 (Egg Nebula): Broadband, Polarimetric, and H2 Line Imaging with NICMOS on the Hubble Space Telescope
Schneider, Glenn; Hines, Dean C.; Rieke, Marcia J. +5 more
High-resolution near-infrared (1.65-2.1 µm) images and 2 µm polarimetric images of the inner 19.5" × 19.3" region of the bipolar protoplanetary nebula CRL 2688, taken with the newly installed Near-Infrared Camera and Multiobject Spectrometer (NICMOS) aboard the Hubble Space Telescope (HST), are reported. The NICMOS images reveal a weal…
Spheroid Luminosity and Mass Functions from Hubble Space Telescope Star Counts
Gould, Andrew; Bahcall, John N.; Flynn, Chris
We analyze 166 spheroid subdwarfs (6.5 < MV < 14.5) found in 53 fields observed with the Wide Field Planetary Camera on the Hubble Space Telescope. The fields cover 221 arcmin2 over a wide range of directions. The spheroid luminosity function (LF) is inconsistent at about the 3 σ level with the local spheroid LF of Dahn…
Coronal Composition above the Solar Equator and the North Pole as Determined from Spectra Acquired by the SUMER Instrument on SOHO
Schühle, U.; Feldman, U.; Laming, J. M. +1 more
Using spectra obtained by the SUMER instrument on the Solar and Heliospheric Observatory (SOHO) we have determined the composition of the bulk of the coronal plasma in the vicinity of the solar surface over a polar coronal hole and an equatorial region. Our measurements show that although low first ionization potential (FIP) elements are enriched …
Keck Spectroscopy and NICMOS Photometry of a Redshift Z = 5.60 Galaxy
Bunker, Andrew; Spinrad, Hyron; Stern, Daniel +4 more
We present Keck Low Resolution Imaging Spectrometer spectroscopy along with Near-Infrared Camera and Multiobject Spectrometer (NICMOS) F110W (~J) and F160W (~H) images of the galaxy HDF 4-473.0 in the Hubble Deep Field (HDF), with a detection of an emission line consistent with Lyα at a redshift of z=5.60. Attention to this object as a high-redshi…
Helioseismic Measurements of the Subsurface Meridional Flow
Braun, D. C.; Fan, Y.
We measure the mean frequencies of acoustic (p-mode) waves propagating toward and away from the poles of the Sun from observations made with the Solar Oscillations Investigation-Michelson Doppler Imager on board the Solar and Heliospheric Observatory and the ground-based Global Oscillations Network Group. We demonstrate that there is a significant…
Ion Temperatures in a Solar Polar Coronal Hole Observed by SUMER on SOHO
Wilhelm, K.; Tu, C. -Y.; Marsch, E. +1 more
The temperatures of some highly charged ions in the southern solar polar coronal hole are determined from the widths of the extreme ultraviolet (EUV) lines measured by the SUMER (Solar Ultraviolet Measurements of Emitted Radiation) instrument on SOHO (Solar and Heliospheric Observatory). Radiation from both light ions, such as Ne6+, Ne<…
Hubble Space Telescope Observations of Neutron-Capture Elements in Very Metal Poor Stars
Truran, James W.; Sneden, Christopher; Cowan, John J. +1 more
Using the Goddard High-Resolution Spectrograph (GHRS) of the Hubble Space Telescope (HST) we have detected the neutron-capture elements osmium, platinum, and lead in the very metal poor ([Fe/H] ~= -2.8) Galactic halo star HD 115444. This star joins the metal-poor giant HD 126238 ([Fe/H] ~= -1.7) as the second Galactic halo star for which ``third n…
Kinematics of the Nuclear Ionized Gas in the Radio Galaxy M84 (NGC 4374)
Kimble, R.; Kraemer, S.; Green, R. F. +17 more
We present optical long-slit spectroscopy of the nucleus of the nearby radio galaxy M84 (NGC 4374 = 3C 272.1) obtained with the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope. Our spectra reveal that the nuclear gas disk seen in the Wide Field Planetary Camera 2 imaging by Bower et al. is rotating rapidly. The velocity curv…
Early-Type Galaxies in the Hubble Deep Field: The Star Formation History
Franceschini, Alberto; Bressan, Alessandro; Fasano, Giovanni +4 more
We have investigated the properties of a complete K-band selected sample of 35 elliptical and S0 galaxies brighter than K = 20.15 mag in the Hubble deep field, as representative of the field galaxy population. This sample has been derived from deep K-band image by the KPNO-IRIM camera, by applying a rigorous morphological classification scheme bas…
The Resolved Stellar Population of the Poststarburst Galaxy NGC 1569
Leitherer, Claus; Clampin, Mark; Nota, Antonella +4 more
We present Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2) photometry of the resolved stellar population in the poststarburst galaxy NGC 1569. The color-magnitude diagram (CMD) derived in the F439W and F555W photometric bands contains ~2800 stars with a photometric error of <=0.2 mag down to mF439, mF555…