A NEW HOT DA WHITE-DWARF IN A REGION OF EXCEPTIONALLY LOW H-1 DENSITY

被引：15

作者：

BARSTOW, MA

WESEMAEL, F

HOLBERG, JB

BUCKLEY, DAH

STOBIE, RS

MITTAZ, JPD

FONTAINE, G

ROSEN, SR

DEMERS, S

LAMONTAGNE, R

IRWIN, MJ

BERGERON, P

KEPLER, SO

VENNES, S

机构：

[1] UNIV MONTREAL, DEPT PHYS, MONTREAL H3C 3J7, QUEBEC, CANADA

[2] UNIV ARIZONA, LUNAR & PLANETARY LAB, TUCSON, AZ 85721 USA

[3] UNIV CAPE TOWN, DEPT ASTRON, RONDEBOSCH 7700, SOUTH AFRICA

[4] S AFRICAN ASTRON OBSERV, CAPE TOWN 7935, SOUTH AFRICA

[5] UCL, MULLARD SPACE SCI LAB, DORKING RH5 6NT, SURREY, ENGLAND

[6] ROYAL GREENWICH OBSERV, CAMBRIDGE CB2 0EZ, ENGLAND

[7] UNIV FED RIO GRANDE SUL, INST FIS, BR-91500 PORTO ALEGRE, RS, BRAZIL

[8] UNIV CALIF BERKELEY, CTR EUV ASTROPHYS, BERKELEY, CA 94720 USA

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 1994年 / 267卷 / 03期

关键词：

STARS; ATMOSPHERES; INDIVIDUAL; RE-0457; 281; WHITE DWARFS; ISM; ABUNDANCES; ULTRAVIOLET;

D O I：

10.1093/mnras/267.3.647

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report the discovery of the hot DA white dwarf RE 0457 - 281 which has the lowest line-of-sight neutral hydrogen column density yet measured. The star was found independently by the ROSAT EUV, Montreal-Cambridge-Tololo and Edinburgh-Cape surveys. With an effective temperature of 60 700 K and very soft EUV spectrum, this white dwarf resembles the well-studied hot DA white dwarf G 191 - B2B. A follow-up observation made using the Voyager 2 UV spectrometer reveals a strong continuum shortward of the 912-A Lyman limit from which we deduce that the neutral hydrogen column density is 1.3 x 10(17) atom cm-2

引用

页码：647 / 652

页数：6

共 30 条

[1] ROSAT STUDIES OF THE COMPOSITION AND STRUCTURE OF DA WHITE-DWARF ATMOSPHERES [J].