Bastien Aracil, David V. Bowen, Edward B. Jenkins
The spectrum of the low-redshift QSO PG0953+415 (zQSO = 0.234) shows two strong, intervening O VI absorption systems. To study the nature of these absorbers, we have used the Gemini Multiobject...
In response to the comments by Murphy et al. (arxiv:0708.3677) (2007)
Srianand, Raghunathan, Chand, Hum, Petitjean, Patrick, Aracil, Bastien
In their comment, Murphy et al. (arxiv:0708.3677) criticize the fitting procedure we used in two previous papers [Srianand et al. 2004(Paper I) and Chand et al. 2004 (Paper II)] and conclude that the...
Tripp, Todd M., Aracil, Bastien, Bowen, David V., Jenkins, Edward B.
The spectrum of the low-redshift QSO PG0953+415 shows two strong, intervening O VI absorption systems. To study the nature of these absorbers, we have used the Gemini Multiobject Spectrograph to...
Chand, Hum, Srianand, Raghunathan, Petitjean, Patrick, Aracil, Bastien, Quast, Ralf, Reimers, Dieter
We present a detailed analysis of a very high resolution (R\approx 112,000) spectrum of the quasar HE 0515-4414 obtained using the High Accuracy Radial velocity Planet Searcher (HARPS) mounted on the...
High Metallicity, Photoionised Gas in Intergalactic Large-Scale Filaments (2005)
Aracil, Bastien, Tripp, Todd M., Bowen, David V., Proschaska, Jason X., Chen, Hsiao-Wen, Frye, Brenda L.
We present high-resolution UV spectra of absorption-line systems toward the low-z QSO HS0624+6907 (z=0.3700). Coupled with spectroscopic galaxy redshifts, we find that many of these absorbers are...
The warm-hot intergalactic medium at z~2.2: Metal enrichment and ionization source (2005)
Bergeron, Jacqueline, Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic...
Metals in the Intergalactic Medium (2005)
Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe, Bergeron, Jacqueline
We use high spectral resolution (R=45000) and high signal-to-noise ratio (S/N \\~ 35-70 per pixel) spectra of 19 high-redshift (2.1
Chand, Hum, Petitjean, Patrick, Srianand, Raghunathan, Aracil, Bastien
We report a new constraint on the variation of the fine-structure constant based on the analysis of 15 Si IV doublets selected from a ESO-UVES sample. We find \Delta\alpha/\alpha = (+0.15+/-0.43) x...
Tripp, Todd M., Jenkins, Edward B., Bowen, David V., Prochaska, Jason X., Aracil, Bastien, Ganguly, Rajib
We present a new UV echelle spectrum of PG1216+069, obtained with HST+STIS, which reveals damped Lya (DLA) absorption as well as O I, C II, Si II, and Fe II absorption lines at z(abs) = 0.00632 near...
Srianand, Raghunathan, Chand, Hum, Petitjean, Patrick, Aracil, Bastien
Most of the successful physical theories rely on the constancy of few fundamental quantities (such as the speed of light, $c$, the fine-structure constant, \alpha, the proton to electron mass ratio,...
Metals in the Intergalactic Medium (2004)
Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe, Bergeron, Jacqueline
We use high spectral resolution (R=45000) and high signal-to-noise ratio (S/N \\~ 35-70 per pixel) spectra of 19 high-redshift (2.1
Metals in the Intergalactic Medium (2004)
Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe, Bergeron, Jacqueline
We use high spectral resolution (R=45000) and high signal-to-noise ratio (S/N \\~ 35-70 per pixel) spectra of 19 high-redshift (2.1
CIV Absorbers in z>4 Quasars: Tracing Early Galactic Halos Evolution (2003)
Peroux, Celine, Petitjean, Patrick, Aracil, Bastien, Irwin, Mike, McMahon, Richard
We use 29 z>4 quasar spectra to build a homogeneous sample of high-redshift CIV absorbers. We use these data to calculate the number density, n(z), of W_rest(CIV)>0.30 A CIV doublets. We find that...
Ellison, Sara L., Ibata, Rodrigo, Pettini, Max, Lewis, Geraint F., Aracil, Bastien, Petitjean, Patrick, ...
We have obtained spatially resolved spectra of the z=3.911 triply imaged QSO APM08279+5255 using the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST). We study...
The Clustering of Intergalactic Metals (2003)
Pichon, Christophe, Scannapieco, Evan, Aracil, Bastien, Petitjean, Patrick, Aubert, Dominique, Bergeron, Jacqueline, ...
We measure the spatial clustering of metals in the intergalactic medium from z = 1.7 to 3.0, as traced by 643 CIV and 104 SiIV N >= 10^12 cm^-2 absorption systems in 19 high signal-to-noise (40-80)...
The Structure of High Redshift Galactic Halos (2003)
Ellison, Sara L., Ibata, Rodrigo, Pettini, Max, Lewis, Geraint F., Aracil, Bastien, Petitjean, Patrick, ...
Observations of multiple or lensed QSOs at high redshift can be used to probe transverse structure in intervening absorption systems. Here we present results obtained from STIS spectroscopy of the...
Metals in the Intergalactic Medium (2003)
Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe, Bergeron, Jacqueline
We use high spectral resolution (R=45000) and high signal-to-noise ratio (S/N \~ 35-70 per pixel) spectra of 19 high-redshift (2.1
The warm-hot intergalactic medium at z~2.2: Metal enrichment and ionization source (2002)
Bergeron, Jacqueline, Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic...
A new measurement of zinc metallicity in a DLA at z=3.35 (2002)
Peroux, Celine, Petitjean, Patrick, Aracil, Bastien, Srianand, R.
We present chemical abundance measurements in the z_abs=3.35045 Damped Lyman-alpha (DLA) system observed in the UVES spectrum of the BAL quasar BR 1117-1329. We measure a neutral hydrogen column...
Lewis, Geraint F., Ibata, Rodrigo A., Ellison, Sara L., Aracil, Bastien, Petitjean, Patrick, Pettini, Max, ...
While gravitationally lensed quasars are expected to display an odd number of images, invariably systems are observed with an even number of quasars. For this, lensing galaxies must have very small...
The warm-hot intergalactic medium at z~2.2: Metal enrichment and ionization source (2002)
Bergeron, Jacqueline, Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic...
The warm-hot intergalactic medium at z~2.2: Metal enrichment and ionization source (2002)
Bergeron, Jacqueline, Aracil, Bastien, Petitjean, Patrick, Pichon, Christophe
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic...
3D Spatial Distribution of the Intergalactic Medium (2001)
Petitjean, Patrick, Rollinde, Emmanuel, Aracil, Bastien, Pichon, Christophe, Colombi, Stéphane
Very recently a new inversion method has been developped to analyze the intergalactic medium seen in absorption in quasar spectra (the so-called Lyman-alpha forest). This method is applied to recover...
Petitjean, Patrick, Aracil, Bastien, Srianand, R., Ibata, Rodrigo
A study of the absorption systems toward the gravitationally lensed quasar APM 08279+5255 is presented. Most of the MgII systems in the redshift range 1.2-2.07, although saturated, show large...