Zobrazeno 11 - 20
of 58
pro vyhledávání: '"Foltz, C. B."'
Publikováno v:
Astrophys.J.549:76-89,2001
We have obtained follow-up observations of the quasar pair LBQS 0107-025A,B and new observations of the nearby quasar LBQS 0107-0232 with the Hubble Space Telescope Faint Object Spectrograph. Extended wavelength coverage of LBQS 0107-025A and B using
Externí odkaz:
http://arxiv.org/abs/astro-ph/0010058
Autor:
White, R. L., Becker, R. H., Gregg, M. D., Laurent-Muehleisen, S. A., Brotherton, M. S., Impey, C. D., Petry, C. E., Foltz, C. B., Chaffee, F. H., Richards, G. T., Oegerle, W. R., Helfand, D. J., McMahon, R. G., Cabanela, J. E.
Publikováno v:
Astrophys.J.Suppl.126:133,2000
We have used the VLA FIRST survey and the APM catalog of the POSS-I plates as the basis for constructing a new radio-selected sample of optically bright quasars. This is the first radio-selected sample that is competitive in size with current optical
Externí odkaz:
http://arxiv.org/abs/astro-ph/9912215
Publikováno v:
Mon.Not.Roy.Astron.Soc.312:827-832,2000
The longstanding question of the extent to which the quasar population is affected by dust extinction, within host galaxies or galaxies along the line of sight, remains open. More generally, the spectral energy distributions of quasars vary significa
Externí odkaz:
http://arxiv.org/abs/astro-ph/9911064
Publikováno v:
Astrophys.J.527:757-777,1999
We present high-quality spectroscopic observations of the two most-metal deficient blue compact galaxies known, I Zw 18 and SBS 0335-052 to determine the helium abundance. The underlying stellar absorption strongly influences the observed intensities
Externí odkaz:
http://arxiv.org/abs/astro-ph/9907228
Hubble Space Telescope (HST) colour - magnitude diagrams in B, V and R along with long-slit Multiple Mirror Telescope (MMT) spectrophotometric data are used to investigate the evolutionary status of the nearby blue compact dwarf (BCD) galaxy I Zw 18.
Externí odkaz:
http://arxiv.org/abs/astro-ph/9907082
Publikováno v:
Astrophys.J.525:105-126,1999
We use Multiple Mirror Telescope (MMT) spectrophotometry and Hubble Space Telescope (HST) Faint Object Spectrograph (FOS) spectra and Wide Field and Planetary Camera 2 (WFPC2) V and I images to study the properties and evolutionary status of the near
Externí odkaz:
http://arxiv.org/abs/astro-ph/9905345
Publikováno v:
Astrophys.J.517:L73,1999
We have observed a sample of 22 luminous quasars, in the range 2.0
Externí odkaz:
http://arxiv.org/abs/astro-ph/9904054
Publikováno v:
Astrophys.J.519:177-184,1999
We present Multiple Mirror Telescope (MMT) and Keck II telescope spectrophotometry and 3.5m Calar Alto telescope R, I photometry of the western component of the extremely low-metallicity blue compact galaxy SBS 0335-052. The components, separated by
Externí odkaz:
http://arxiv.org/abs/astro-ph/9902368
Publikováno v:
Astrophys.J. 514 (1999) 40
We have obtained H-band spectra of 32 luminous quasars at 2.0
Externí odkaz:
http://arxiv.org/abs/astro-ph/9810287
Publikováno v:
Mon.Not.Roy.Astron.Soc.295:573-586,1998
We present both photometry and spectra of the individual images of the quadruple gravitational lens system Q2237+0305. Comparison of spectra obtained at two epochs, separated by $\sim~3\,$years, shows evidence for significant changes in the emission
Externí odkaz:
http://arxiv.org/abs/astro-ph/9711018