Zobrazeno 1 - 10
of 215
pro vyhledávání: '"Sargent, Wallace L. W."'
Using Voigt-profile-fitting procedures on Keck HIRES spectra of nine QSOs we identify 1099 CIV absorber components clumped in 201 systems outside the Lyman forest over 1.6 < z < 4.4. With associated SiIV, CII, SiII and NV where available we investiga
Externí odkaz:
http://arxiv.org/abs/1410.3784
Autor:
Rauch, Michael, Becker, George D., Haehnelt, Martin G., Gauthier, Jean-Rene, Sargent, Wallace L. W.
We report the observation of a further asymmetric, extended Lyman alpha emitting halo at z=2.63, from our ultra-deep, long-slit spectroscopic survey of faint high redshift emitters, undertaken with Magellan LDSS3 in the GOODS-S field. The Lya emissio
Externí odkaz:
http://arxiv.org/abs/1206.2680
We present measurements of carbon, oxygen, silicon, and iron in quasar absorption systems existing when the universe was roughly one billion years old. We measure column densities in nine low-ionization systems at 4.7 < z < 6.3 using Keck, Magellan,
Externí odkaz:
http://arxiv.org/abs/1111.4843
Autor:
Bolton, James S., Becker, George D., Raskutti, Sudhir, Wyithe, J. Stuart B., Haehnelt, Martin G., Sargent, Wallace L. W.
We present measurements of the intergalactic medium (IGM) temperature within ~5 proper Mpc of seven luminous quasars at z~6. The constraints are obtained from the Doppler widths of Lyman-alpha absorption lines in the quasar near-zones and build upon
Externí odkaz:
http://arxiv.org/abs/1110.0539
Autor:
Rauch, Michael, Becker, George D., Haehnelt, Martin G., Gauthier, Jean-Rene, Ravindranath, Swara, Sargent, Wallace L. W.
We present observations of a peculiar Lyman alpha-emitting galaxy at redshift 3.344, discovered in a deep, blind spectroscopic survey for faint Lyman alpha emitters with the Magellan II telescope in the Hubble Ultra Deep Field (HUDF). The galaxy exhi
Externí odkaz:
http://arxiv.org/abs/1105.4876
We present a survey for low-ionization metal absorption line systems towards 17 QSOs at redshifts z_em=5.8-6.4. Nine of our objects were observed at high resolution with either Keck/HIRES or Magellan/MIKE, and the remainder at moderate resolution wit
Externí odkaz:
http://arxiv.org/abs/1101.4399
We present new measurements of the temperature of the intergalactic medium (IGM) derived from the Lyman-alpha forest over 2.0 < z < 4.8. The small-scale structure in the forest of 61 high-resolution QSO spectra is quantified using a new statistic, th
Externí odkaz:
http://arxiv.org/abs/1008.2622
Autor:
Penprase, Bryan E., Prochaska, J. Xavier, Sargent, Wallace L. W., Martinez, Irene Toro, Beeler, Daniel J.
We present the first results from a survey of SDSS quasars selected for strong H I damped Lyman-{\alpha} (DLA) absorption with corresponding low equivalent width absorption from strong low-ion transitions (e.g. C II {\lambda}1334 and Si II {\lambda}1
Externí odkaz:
http://arxiv.org/abs/1006.4119
Autor:
Bolton, James S., Becker, George D., Wyithe, J. Stuart B., Haehnelt, Martin G., Sargent, Wallace L. W.
The thermal state of the intergalactic medium (IGM) provides an indirect probe of both the HI and HeII reionisation epochs. Current constraints on the IGM temperature from the Lya forest are restricted to the redshift range 2
Externí odkaz:
http://arxiv.org/abs/1001.3415
Publikováno v:
Astrophys.J.Suppl.183:1-16,2009
We present new central stellar velocity dispersion measurements for 428 galaxies in the Palomar spectroscopic survey of bright, northern galaxies. Of these, 142 have no previously published measurements, most being relatively late-type systems with l
Externí odkaz:
http://arxiv.org/abs/0906.4105