Search Publications
Caltech Faint Galaxy Redshift Survey. XIII. Spectral Energy Distributions for Galaxies in the Region of the Hubble Deep Field North
Cohen, Judith G.
We introduce a new empirical function for modeling the spectral energy distributions (SEDs) of galaxies. We apply it to a sample of 590 galaxies in the region of the Hubble Deep Field (HDF) with z<1.5 using multicolor photometry with wide wavelength coverage combined with spectroscopic redshifts from our 93% complete R-selected redshift survey …
2 Micron Narrowband Adaptive Optics Imaging in the Arches Cluster
Schaerer, D.; Schmutz, W.; Heydari-Malayeri, M. +3 more
Canada-France-Hawaii-Telescope adaptive optics bonnette images through narrowband filters in the K band are presented for the Arches cluster. Continuum fluxes, line fluxes, and equivalent widths are derived from high angular resolution images, some nearly diffraction limited, for the well-known massive stars in the Arches cluster. Images were obta…
A Near-Infrared Stellar Census of Blue Compact Dwarf Galaxies: The Wolf-Rayet Galaxy I Zw 36
Greggio, Laura; Hopp, Ulrich; Schulte-Ladbeck, Regina E. +2 more
We report the results of near-IR imaging in J and H, of I Zw 36 (~Zsolar/14) with the Hubble Space Telescope. Whereas imaging with the pre-COSTAR Faint Object Camera (FOC) previously resolved hot and massive stars in the near-UV, the NICMOS data furnish a census of the cool, intermediate- and low-mass stars. There clearly was star forma…
The Interaction between the Interstellar Medium and Star Formation in the Dwarf Starburst Galaxy NGC 4214
Scoville, Nick; Walter, Fabian; Taylor, Christopher L. +2 more
We present the first interferometric study of the molecular gas in the metal-poor dwarf starburst galaxy NGC 4214. Our map of the 12CO (1-0) emission, obtained at the Owens Valley Radio Observatory's millimeter array, reveals an unexpected structural wealth. We detected three regions of molecular emission in the northwest, southeast, an…
Interstellar Bubbles in Two Young H II Regions
Danforth, Charles W.; Nazé, Yaël; Chu, You-Hua +3 more
Massive stars are expected to produce wind-blown bubbles in the interstellar medium; however, ring nebulae, suggesting the existence of bubbles, are rarely seen around main-sequence O stars. To search for wind-blown bubbles around main-sequence O stars, we have obtained high-resolution Hubble Space Telescope WFPC2 images and high-dispersion echell…
Are There Blue, Massive E/S0 Galaxies at z<1? Kinematics of Blue Spheroidal Galaxy Candidates
Gebhardt, Karl; Faber, S. M.; Willmer, Christopher N. A. +5 more
Several recent studies find that 10%-50% of morphologically selected field early-type galaxies at redshifts z<~1 have blue colors indicative of recent star formation. Such ``blue spheroids'' might be massive early-type galaxies with active star formation, perhaps induced by recent merger events. Alternatively, they could be starbursting, low-ma…
Seeing Galaxies through Thick and Thin. III. Hubble Space Telescope Imaging of the Dust in Backlit Spiral Galaxies
White, Raymond E., III; Keel, William C.
We present analysis of Wide Field Planetary Camera 2 imaging of two spiral galaxies partially backlit by elliptical or S0 systems in the pairs AM 1316-241 and AM 0500-620, as well as the (probably spiral) foreground system in NGC 1275. Images in B and I are used to determine the reddening curve of dust in these systems. The foreground spiral compo…
Statistical Properties of Ultraluminous IRAS Galaxies from an HST Imaging Survey
Mao, S.; Cui, J.; Xia, X. -Y. +2 more
We perform photometric measurements on a large HST snapshot imaging survey sample of 97 ultraluminous infrared galaxies (ULIRGs). We select putative nuclei from bright clumps in all the sample targets, mainly based on a quantitative criterion of I-band luminosity as well as the global and local morphological information. All the sources are then c…
The Tolman Surface Brightness Test for the Reality of the Expansion. IV. A Measurement of the Tolman Signal and the Luminosity Evolution of Early-Type Galaxies
Sandage, Allan; Lubin, Lori M.
We review a sample of the early literature in which the reality of the expansion is discussed. Hubble's reluctance, even as late as 1953, to accept the expansion as real is explained as due to his use of equations for distances and absolute magnitudes of redshifted galaxies that do not conform to the modern Mattig equations of the standard model. …
3C 236: Radio Source, Interrupted?
Koekemoer, Anton M.; Baum, Stefi A.; O'Dea, Christopher P. +5 more
We present new Hubble Space Telescope Space Telescope Imaging Spectrograph MAMA near-UV images and archival Wide Field Planetary Camera 2 (WFPC2) V- and R-band images that reveal the presence of four star-forming regions in an arc along the edge of the dust lane in the giant (4 Mpc) radio galaxy 3C 236. Two of the star-forming regions are relative…