THE RADIO TIME-DELAY IN THE DOUBLE QUASAR 0957+561

被引:77
作者
LEHAR, J [1 ]
HEWITT, JN [1 ]
ROBERTS, DH [1 ]
BURKE, BF [1 ]
机构
[1] BRANDEIS UNIV,DEPT PHYS,WALTHAM,MA 02254
关键词
GRAVITATIONAL LENSING; QUASARS; INDIVIDUAL; (0957+561);
D O I
10.1086/170887
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Gravitational lens models for the double quasar 0957 + 561 predict that there should be a time delay of roughly 1 year between the arrival of wave fronts from the two images. In order to measure this delay, we have been monitoring the flux densities at lambda = 6 cm of 0957 + 561A and 0957 + 561B since 1979. We present the flux curves of the two images constructed from the VLA data, which are accurate to 2% of the image flux densities. The VLA data are best fitted by a time delay of 1.40 +/- 0.1 yr (513 +/- 40 days, A leading), with a magnification ratio (B/A) of 0.697 +/- 0.003. The error estimates were obtained through Monte Carlo methods, and include 68% of the simulated solutions.
引用
收藏
页码:453 / 466
页数:14
相关论文
共 42 条
[1]   RELATIVISTIC JETS AS COMPACT RADIO-SOURCES [J].
BLANDFORD, RD ;
KONIGL, A .
ASTROPHYSICAL JOURNAL, 1979, 232 (01) :34-48
[2]  
BONOMETTI RJ, 1985, THESIS MIT
[3]  
BORGEEST U, 1984, ASTRON ASTROPHYS, V141, P318
[4]   FLUX VARIATIONS OF QSO-0957+561A,B AND IMAGE SPLITTING BY STARS NEAR THE LIGHT PATH [J].
CHANG, K ;
REFSDAL, S .
NATURE, 1979, 282 (5739) :561-564
[5]   THE DISCRETE CORRELATION-FUNCTION - A NEW METHOD FOR ANALYZING UNEVENLY SAMPLED VARIABILITY DATA [J].
EDELSON, RA ;
KROLIK, JH .
ASTROPHYSICAL JOURNAL, 1988, 333 (02) :646-659
[6]  
FALCO E, 1989, GRAVITATIONAL LENSES, P96
[7]   NEW MODEL FOR THE 0957+561 GRAVITATIONAL LENS SYSTEM - BOUNDS ON MASSES OF A POSSIBLE BLACK-HOLE AND DARK MATTER AND PROSPECTS FOR ESTIMATION OF H0 [J].
FALCO, EE ;
GORENSTEIN, MV ;
SHAPIRO, II .
ASTROPHYSICAL JOURNAL, 1991, 372 (02) :364-379
[8]  
FLORENTINNIELSEN R, 1984, ASTRON ASTROPHYS, V138, pL19
[9]   THE MILLI-ARCSECOND IMAGES OF Q0957+561 [J].
GORENSTEIN, MV ;
SHAPIRO, II ;
ROGERS, AEE ;
COHEN, NL ;
COREY, BE ;
PORCAS, RW ;
FALCO, EE ;
BONOMETTI, RJ ;
PRESTON, RA ;
RIUS, A ;
WHITNEY, AR .
ASTROPHYSICAL JOURNAL, 1984, 287 (02) :538-548
[10]   VLBI OBSERVATIONS OF THE GRAVITATIONAL LENS SYSTEM 0957+561 - STRUCTURE AND RELATIVE MAGNIFICATION OF THE A-IMAGES AND B-IMAGES [J].
GORENSTEIN, MV ;
COHEN, NL ;
SHAPIRO, II ;
ROGERS, AEE ;
BONOMETTI, RJ ;
FALCO, EE ;
BARTEL, N ;
MARCAIDE, JM .
ASTROPHYSICAL JOURNAL, 1988, 334 (01) :42-58