The optical/near-infrared counterpart of the integral obscured source IGR J16318-4848:: An sgB[e] in a high-mass X-ray binary?

被引:103
作者
Filliatre, P
Chaty, S
机构
[1] Ctr Etud Saclay, CEA, DSM,DAPNIA,SAp, Serv Astrophys, F-91191 Gif Sur Yvette, France
[2] Federat Astroparticule & Cosmol, Paris, France
[3] Univ Paris 07, F-75005 Paris, France
关键词
circumstellar matter; stars; emission-line; Be; X-rays : binaries;
D O I
10.1086/424869
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The X-ray source IGR J16318-4848 was the first source discovered by INTEGRAL on 2003 January 29. The high-energy spectrum exhibits such a high column density that the source is undetectable in X-rays below 2 keV. On 2003 February 23-25, we triggered our Target of Opportunity (ToO) program using the EMMI and SOFI instruments on the New Technology Telescope of the European Southern Observatory (La Silla) to obtain optical and near-infrared (NIR) observations. We confirm the already proposed NIR counterpart and for the first time extended detection into optical. We report here photometric measurements in the R, I, and J bands, upper flux limits in the Bb and V bands, and lower flux limits in the H and K-s bands. We also obtain NIR spectroscopy between 0.95 and 2.52 mum, revealing a large number of emission lines, including forbidden iron lines and P Cygni profiles, and showing a strong similarity with CI Cam, another strongly absorbed source. Together with the spectral energy distribution (SED), these data point to a high-luminosity, high-temperature source, with an intrinsic optical/NIR absorption greater than the interstellar absorption but 2 orders of magnitude below the X-ray absorption. We propose the following picture to match the data: the source is a high-mass X-ray binary (HMXB) at a distance between 0.9 and 6.2 kpc, and the optical/NIR counterpart corresponds to the mass donor, which is an early-type star, maybe an sgB[e] star, surrounded by a dense and absorbing circumstellar material. This would make the second HMXB with an sgB[e] star as the mass donor after CI Cam. Such sources may represent a different evolutionary state of X-ray binaries previously undetected with the lower energy space telescopes; if so, a new class of strongly absorbed X-ray binaries is being unveiled by INTEGRAL.
引用
收藏
页码:469 / 484
页数:16
相关论文
共 45 条
[31]  
PREDEHL P, 1995, ASTRON ASTROPHYS, V293, P889
[32]   RXTE observations of the strongly absorbed sources IGR J16318-4848 and IGR J16358-4726 [J].
Revnivtsev, MG .
ASTRONOMY LETTERS-A JOURNAL OF ASTRONOMY AND SPACE ASTROPHYSICS, 2003, 29 (10) :644-648
[33]   IGR J16318-4848: An X-ray source in a dense envelope? [J].
Revnivtsev, MG ;
Sazonov, SY ;
Gilfanov, MR ;
Sunyaev, RA .
ASTRONOMY LETTERS-A JOURNAL OF ASTRONOMY AND SPACE ASTROPHYSICS, 2003, 29 (09) :587-593
[34]  
RIBO M, 2004, ATEL, V235, P1
[35]   High-dispersion spectroscopy of the X-ray transient RXTE J0421+560 (=CI Camelopardalis) during outburst [J].
Robinson, EL ;
Ivans, II ;
Welsh, WF .
ASTROPHYSICAL JOURNAL, 2002, 565 (02) :1169-1182
[36]   An XMM-Newton observation of IGR J16320-4751 = AX J1631.9-4752 [J].
Rodriguez, J ;
Tomsick, JA ;
Foschini, L ;
Walter, R ;
Goldwurm, A ;
Corbel, S ;
Kaaret, P .
ASTRONOMY & ASTROPHYSICS, 2003, 407 (02) :L41-L45
[37]  
RUELASMAYORGA RA, 1991, REV MEX ASTRON ASTR, V22, P27
[38]   Star-forming complexes and the spiral structure of our Galaxy [J].
Russeil, D .
ASTRONOMY & ASTROPHYSICS, 2003, 397 (01) :133-146
[39]  
SCHARTEL N, 2003, 8072 IAU, P3
[40]   Infrared [Fe II] emission in the circumstellar nebulae of luminous blue variables [J].
Smith, N .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2002, 336 (02) :L22-L26