HI absorption in a gravitational lens at z ∼ 0.7645

被引:29
作者
Kanekar, N
Briggs, FH
机构
[1] Univ Groningen, Kapteyn Inst, NL-9700 AV Groningen, Netherlands
[2] Australian Natl Univ, Mt Stromlo & Siding Spring Observ, RSAA, Weston, ACT 2611, Australia
关键词
galaxies : individual : PMN J0134-0931; gravitational lensing; radio lines; ISM;
D O I
10.1051/0004-6361:20031676
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We have used the Westerbork Synthesis Radio Telescope to detect HI 21 cm absorption at z similar to 0.7645 in the gravitational lens system towards PMN J0134-0931. The 21 cm profile has two broad components, with peak optical depths of 0.047 +/- 0.007 and 0.039 +/- 0.007, at heliocentric redshifts 0.76470 +/- 0.00006 and 0.76348 +/- 0.00006, respectively. The redshift of the stronger component matches that of CaII H and K absorption detected earlier. The absorption has a total velocity width of similar to 500 km s(-1) (between nulls) and an equivalent width of 7.1 +/- 0.08 km s(-1). This would imply a total HI column density of 2.6 +/- 0.3 x 10(21) cm(-2), for a spin temperature of 200 K and a covering factor of unity. The high estimated HI column density is consistent with the presence of large amounts of dust at the lens redshift; the intervening dust could be responsible for the extremely red colour of the background quasar.
引用
收藏
页码:L29 / L32
页数:4
相关论文
共 18 条
[1]  
[Anonymous], GALACTIC ASTRONOMY
[2]  
BAARS JWM, 1977, ASTRON ASTROPHYS, V61, P99
[3]   PHYSICAL-PROPERTIES OF NEUTRAL GAS IN M31 AND THE GALAXY [J].
BRAUN, R ;
WALTERBOS, RAM .
ASTROPHYSICAL JOURNAL, 1992, 386 (01) :120-&
[4]   MAGNESIUM, IRON, AND CALCIUM IN THE Z=0.39498 21 CENTIMETER ABSORBER OF PKS 1229-021 [J].
BRIGGS, FH ;
TURNSHEK, DA ;
SCHAEFFER, J ;
WOLFE, AM .
ASTROPHYSICAL JOURNAL, 1985, 293 (02) :387-393
[5]   THE REDSHIFT OF THE LENSING GALAXY IN THE GRAVITATIONALLY LENSED SYSTEM B0218+35.7 [J].
BROWNE, IWA ;
PATNAIK, AR ;
WALSH, D ;
WILKINSON, PN .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1993, 263 (03) :L32-L36
[6]   NEUTRAL HYDROGEN-21 CENTIMETER ABSORPTION AT Z=0.6847 TOWARD THE SMALLEST EINSTEIN RING [J].
CARILLI, CL ;
RUPEN, MP ;
YANNY, B .
ASTROPHYSICAL JOURNAL, 1993, 412 (02) :L59-L62
[7]  
Chengalur JN, 1999, ASTRON ASTROPHYS, V343, pL79
[8]   The reddest quasars [J].
Gregg, MD ;
Lacy, M ;
White, RL ;
Glikman, E ;
Helfand, D ;
Becker, RH ;
Brotherton, MS .
ASTROPHYSICAL JOURNAL, 2002, 564 (01) :133-142
[9]   The redshift of a lensing galaxy in PMN J0134-0931 [J].
Hall, PB ;
Richards, GT ;
York, DG ;
Keeton, CR ;
Bowen, DV ;
Schneider, DP ;
Schlegel, DJ ;
Brinkmann, J .
ASTROPHYSICAL JOURNAL, 2002, 575 (02) :L51-L54
[10]   Detection of OH and wide HI absorption toward B0218+357 [J].
Kanekar, N ;
Chengalur, JN ;
de Bruyn, AG ;
Narasimha, D .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2003, 345 (01) :L7-L11