Access

Article

Nature 398, 389-394 (1 April 1999) | doi:10.1038/18821; Received 12 February 1999; Accepted 1 March 1999

Open Innovation Challenges

naturejobs

More science jobs
Post a job for free

The afterglow, redshift and extreme energetics of the big gamma-ray burst of 23 January 1999

S. R. Kulkarni1, S. G. Djorgovski1, S. C. Odewahn1, J. S. Bloom1, R. R. Gal1, C. D. Koresko1, F. A. Harrison1, L. M. Lubin1, L. Armus2, R. Sari3, G. D. Illingworth4, D. D. Kelson5, D. K. Magee4, P. G. van Dokkum6, D. A. Frail7, J. S. Mulchaey8, M. A. Malkan9, I. S. McClean9, H. I. Teplitz10, D. Koerner11, D. Kirkpatrick2, N. Kobayashi12, I.-A. Yadigaroglu13, J. Halpern13, T. Piran13, R. W. Goodrich14, F. H. Chaffee14, M. Feroci15 & E. Costa15

  1. Palomar Observatory 105-24, Caltech, Pasadena, California 91125, USA;
  2. Infrared Processing & Analysis Center, Caltech, Pasadena, California 91125, USA;
  3. Theoretical Astrophysics 130-33, Caltech , Pasadena, California 91125, USA;
  4. Lick Observatory, University of California, Santa Cruz, California 95064, USA;
  5. Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Rd, NW, Washington DC 20015, USA;
  6. Kapteyn Astronomical Institute, PO Box 800, NL-9700 AV, Groningen, The Netherlands ;
  7. National Radio Astronomy Observatory, PO Box O, Socorro, New Mexico 87801, USA;
  8. Observatories of the Carnegie Institution, 813 Santa Barbara Street, Pasadena, California 91101, USA;
  9. Department of Physics & Astronomy, University of California, Los Angeles, California 90095-1562 , USA;
  10. Goddard Space Flight Center, Code 681 , Greenbelt, Maryland 20771, USA;
  11. University of Pennsylvania, 4N14 DRL, 209 S. 33rd Street, Philadelphia, Pennsylvania 19104-6396, USA;
  12. Subaru Telescope, National Astronomical Observatory of Japan, 650 N. A'ohoku Place, Hilo, Hawaii 96720, USA;
  13. Department of Astronomy, Columbia University, 538 W. 120th Street, New York, New York 10027, USA;
  14. W. M. Keck Observatory, 65-1120 Mamalahoa Highway, Kamuela, Hawaii 96743, USA;
  15. Istituto di Astrofisica Spaziale, CNR, via Fosso del Cavaliere, Roma I-00133, Italy.

Correspondence to: S. R. Kulkarni1 Correspondence and requests for materials should be addressed to S.R.K. (e-mail: Email: srk@astro.caltech.edu).

Top

Long-lived emission, known as afterglow, has now been detected from about a dozen gamma-ray bursts. Distance determinations place the bursts at cosmological distances, with redshifts, z, ranging from approx1 to 3. The energy required to produce these bright gamma-ray flashes is enormous: up to approx10 53 erg, or 10 per cent of the rest-mass energy of a neutron star, if the emission is isotropic. Here we present optical and near-infrared observations of the afterglow of GRB990123, and we determine a redshift of z greater than or equal to 1.6. This is to date the brightest gamma-ray burst with a well-localized position and if the gamma-rays were emitted isotropically, the energy release exceeds the rest-mass energy of a neutron star, so challenging current theoretical models of the sources. We argue, however, that our data may provide evidence of beamed (rather than isotropic) radiation, thereby reducing the total energy released to a level where stellar-death models are still tenable.

  1. Palomar Observatory 105-24, Caltech, Pasadena, California 91125, USA;
  2. Infrared Processing & Analysis Center, Caltech, Pasadena, California 91125, USA;
  3. Theoretical Astrophysics 130-33, Caltech , Pasadena, California 91125, USA;
  4. Lick Observatory, University of California, Santa Cruz, California 95064, USA;
  5. Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Rd, NW, Washington DC 20015, USA;
  6. Kapteyn Astronomical Institute, PO Box 800, NL-9700 AV, Groningen, The Netherlands ;
  7. National Radio Astronomy Observatory, PO Box O, Socorro, New Mexico 87801, USA;
  8. Observatories of the Carnegie Institution, 813 Santa Barbara Street, Pasadena, California 91101, USA;
  9. Department of Physics & Astronomy, University of California, Los Angeles, California 90095-1562 , USA;
  10. Goddard Space Flight Center, Code 681 , Greenbelt, Maryland 20771, USA;
  11. University of Pennsylvania, 4N14 DRL, 209 S. 33rd Street, Philadelphia, Pennsylvania 19104-6396, USA;
  12. Subaru Telescope, National Astronomical Observatory of Japan, 650 N. A'ohoku Place, Hilo, Hawaii 96720, USA;
  13. Department of Astronomy, Columbia University, 538 W. 120th Street, New York, New York 10027, USA;
  14. W. M. Keck Observatory, 65-1120 Mamalahoa Highway, Kamuela, Hawaii 96743, USA;
  15. Istituto di Astrofisica Spaziale, CNR, via Fosso del Cavaliere, Roma I-00133, Italy.

Correspondence to: S. R. Kulkarni1 Correspondence and requests for materials should be addressed to S.R.K. (e-mail: Email: srk@astro.caltech.edu).