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Full-Text Articles in Physical Sciences and Mathematics
The Vlt Lbg Redshift Survey I: Clustering And Dynamics Of ≈ 1000 Galaxies At Z ≈ 3⋆, R. M. Bielby, T. Shanks, P. M. Weilbacher, L. Infante, N. H.M. Crighton, C. Bornancini, N. Bouché, P. Héraudeau, D. G. Lambas, James D. Lowenthal, D. Minniti, N. Padilla, P. Petitjean, T. Theuns
The Vlt Lbg Redshift Survey I: Clustering And Dynamics Of ≈ 1000 Galaxies At Z ≈ 3⋆, R. M. Bielby, T. Shanks, P. M. Weilbacher, L. Infante, N. H.M. Crighton, C. Bornancini, N. Bouché, P. Héraudeau, D. G. Lambas, James D. Lowenthal, D. Minniti, N. Padilla, P. Petitjean, T. Theuns
Astronomy: Faculty Publications
We present the initial imaging and spectroscopic data acquired as part of the Very Large Telescope (VLT) VIMOS Lyman-break galaxy Survey. UBR (or UBVI) imaging covers five ≈36 × 36 arcmin fields centred on bright z > 3 quasi-stellar objects (QSOs), allowing ≈210002 < z < 3.5 galaxy candidates to be selected using the Lyman-break technique. We performed spectroscopic follow-up using VLT VIMOS, measuring redshifts for 1020 z > 2 Lyman-break galaxies and 10 z > 2 QSOs from a total of 19 VIMOS pointings. From the galaxy spectra, we observe a 625 ± 510kms velocity offset between the interstellar absorption and Lyman α emission-line redshifts, consistent with previous results. Using the photometric and spectroscopic catalogues, we have analysed the galaxy clustering at z≈ 3. The angular correlation …
The Vlt Lbg Redshift Survey- Ii. Interactions Between Galaxies And The Igm At Z ~ 3, N. H.M. Crighton, R. Bielby, T. Shanks, L. Infante, C. G. Bornancini, N. Bouché, D. G. Lambas, James D. Lowenthal, D. Minniti, S. L. Morris, N. Padilla, C. Péroux, P. Petitjean, T. Theuns, P. Tummuangpak, P. M. Weilbacher, L. Wisotzki, G. Worseck
The Vlt Lbg Redshift Survey- Ii. Interactions Between Galaxies And The Igm At Z ~ 3, N. H.M. Crighton, R. Bielby, T. Shanks, L. Infante, C. G. Bornancini, N. Bouché, D. G. Lambas, James D. Lowenthal, D. Minniti, S. L. Morris, N. Padilla, C. Péroux, P. Petitjean, T. Theuns, P. Tummuangpak, P. M. Weilbacher, L. Wisotzki, G. Worseck
Astronomy: Faculty Publications
We have measured redshifts for 243 z≈ 3 quasars in nine Very Large Telescope (VLT) Visible Imaging and Multi-Object Spectrograph (VIMOS) Lyman-break galaxy (LBG) redshift survey areas, each of which is centred on a known bright quasar. Using the spectra of these quasars, we measure the cross-correlation between neutral hydrogen gas causing the Lyα forest and 1020 LBGs at z≈ 3. We find an increase in neutral hydrogen absorption within ≈5h Mpc of a galaxy in agreement with the results of Adelberger et al. The Lyα-LBG cross-correlation can be described by a power law on scales larger than 3h Mpc. …
The Lyman Continuum In Starburst Galaxies Observed With The Hopkins Ultraviolet Telescope, Claus Leitherer, Henry C. Ferguson, Timothy M. Heckman, James D. Lowenthal
The Lyman Continuum In Starburst Galaxies Observed With The Hopkins Ultraviolet Telescope, Claus Leitherer, Henry C. Ferguson, Timothy M. Heckman, James D. Lowenthal
Astronomy: Faculty Publications
The starburst galaxies IRAS 08339+6517, Mrk 1267, Mrk 66, and Mrk 496 (=NGC 6090) were observed with the Hopkins Ultraviolet Telescope (HUT) during the Astro-2 mission. All four galaxies have radial velocities larger than 5000 km s-1, permitting the measurement of their intrinsic Lyman continuum fluxes redward of the H I absorption edge in our Galaxy. The sample was selected on the basis of having the most favorable conditions for the escape of Lyman continuum photons. Two a upper limits of Fk < 7 X 10-16 ergs s-1 cm-2 A-1 were obtained for the flux around 900 A within the rest frame of each galaxy.A set of theoretical spectral energy distributions has been calculated. We show that there exists a tight correlation between the continuum luminosity at 900 A and the total number of photons emitted in the Lyman continuum, which is valid for high- and low-metallicity galaxies and essentially all relevant initial mass functions and star formation histories. Comparison with the observed values suggests that, on average, less than 3% of the intrinsic Lyman continuum photons escape from the program galaxies. Models for the ionization of the intergalactic medium at high 2 by young starbursts require a significant fraction of the ionizing radiation to escape from the galaxy. If the four galaxies observed by us have properties similar to young galaxies at redshift 2 2 3, such galaxies are not likely to provide Lyman continuum photons for the ionization of the early universe.