Figure 1: An artist's rendition of the central region of the quasar. A gaseous disk surrounds a central black hole. The outflow is gas streaming from the disk outward along the curved mesh, which indicates the distortion of space/time, and is distinguished from a jet that is blowing vertically. The arrows A, B, and C indicate the light paths observed, which probably pass near the surface of an outflow. (Credit: Shinshu University and the National Astronomical Observatory of Japan)
The research paper on which this release is based was published on-line in the January 15, 2013 edition of The Astronomical Journal: T. Misawa et al., "Spectroscopy along Multiple, Lensed Sight Lines through Outflowing Winds in the Quasar SDSS J1029+2623", vol. 145, issue 2, article id. 48 (2013). The authors of the paper are:
- T. Misawa, Shinshu University, Japan
- N. Inada, Nara National College of Technology, Japan
- K. Ohsuga, National Astronomical Observatory of Japan, Japan
- P. Gandhi, Institute of Space and Astronautical Science, Japan
- R. Takahashi, Tomakomai National College of Technology, Japan
- M. Oguri, Kavli Institute for the Physics and Mathematics of the Universe, Japan
This research was supported by the following:
- Special Postdoctoral Research Program of RIKEN, the Japan Society for the Promotion of Science (23740148, 23740161)
- Shinshu University Research Grant for Exploratory Research by Young Scientists
- The FIRST program "Subaru Measurements of Images and Redshifts (SuMIRe)"
- World Premier International Research Center Initiative (WPI Initiative), MEXT, Japan
- It corresponds to a redshift of z~2.197. A "z" or redshift value measures how much the expansion of space has stretched the light from an object. Generally, the greater the observed z value for a galaxy, the more distant it is in time and space from Earth.
- Because their appearance is star-like, they are called "quasi-stellar objects" and abbreviated as quasars.
- An international team led by Naohisa Inada and Masamune Oguri (both are members of the current research team) discovered the first quasar (SDSS J1004+4112) that is lensed by a cluster of galaxies (http://www.sdss.org/news/releases/20031217.lensing.html). Only three quasars that are lensed by a cluster of galaxies have been discovered so far (SDSS J1004+4112, SDSS J1029+2623, and SDSS J2222+2745). Among them, SDSS J1029+2623 has the largest separation angle.
- 1 arcsec (1") is a unit of angle, defined as 1/3600 of 1 degree. Human eyes cannot distinguish such a small angle.
- The observed flux ratio of the three lensed images is A:B:C ~ 0.95:1.00:0.24.
- This means that an absorber only partially covers the background light source toward the sight line. Because foreground interstellar or intergalactic media are larger than the light source of the quasar by more than several orders, only small gas clouds in the vicinity of the quasar can reproduce a partial coverage.
- Similar observation has been also performed for the other lensed quasar DSS J1004+4112 (Green, P. 2006, the Astrophysical Journal, vol. 644, pp.733-741).
- The image A leads the image B by 744 days (Fohlmeister, J. et al., 2013, The Astrophysical Journal, vol. 764, 186).