Absorption systems in the spectrum of GRB 021004 ⋆
نویسنده
چکیده
We report on a 3600 s spectrum of GRB 021004 obtained with the Nordic Optical Telecope on La Palma 10.71 hours after the burst. We identify absorption lines from five systems at redshifts 1.3806, 1.6039, 2.2983, 2.3230, and 2.3292. In addition we find an emission line which, if due to Lyα from the host galaxy, gives a redshift of 2.3351. The nearest absorber is blueshifted by 530 km s with respect to this line, consistent with shifts seen in Damped Lyα and Lyman-Break galaxies at similar redshifts. The emission line flux is 2.46 ± 0.50 × 10 erg s cm. Some of the absorption systems are “line-locked”, an effect often seen in QSO absorption systems believed to originate close to the QSO central engine.
منابع مشابه
GRB 021004: a Massive Progenitor Star Surrounded by Shells
We present spectra of the optical transient of GRB 021004 obtained with the HobbyEberly Telescope starting 15.48, 20.31 hours, and 4.84 days after the γ-ray burst and a spectrum obtained with the H. J. Smith 2.7 m Telescope starting 14.31 hours after the γ-ray burst. GRB 021004 is the first burst afterglow for which the spectrum is dominated by absorption lines from high ionization species with...
متن کاملThe afterglow of GRB 021004: surfing on density waves
We present a model for the early optical afterglow of GRB 021004. This burst had one of the earliest detected optical afterglows, allowing a dense optical sampling. The lightcurve was peculiar, since bright bumps were superimposed to the regular power-law decay observed in many other events. We show that, given their time scale and shape, the bumps are due to the interaction of the fireball wit...
متن کاملNew search strategy for high z intervening absorbers : GRB 021004 , a pilot study ⋆
We present near-infrared narrow-and broad-band imaging of the field of GRB 021004, performed with ISAAC on the UT1 of the ESO Very Large Telescope. The narrow-band filters were chosen to match prominent emission lines at the redshift of the absorption-line systems found against the early-time afterglow of GRB 021004: [O iii] at z=1.38 and Hα at z=1.60, respectively. For the z=1.38 system we fin...
متن کامل6 v 1 1 4 Ja n 20 03 Spectropolarimetry of GRB 021004 - Evidence for High Velocity Ly − α Absorptions
We present spectropolarimetry observations of GRB 021004 obtained at the ESO VLT. We detect a remarkable increase of the degree of polarization blueward of the host galaxy rest frame Ly − α to about 5-10% that corresponds to a decrease in the continuum flux below the extrapolation of a power law. An increase of the degree of polarization is also recorded in some narrow lines, but of lower stati...
متن کاملar X iv : a st ro - p h / 04 09 71 7 v 2 1 4 Fe b 20 05 A flash in the dark : UVES / VLT high resolution spectroscopy of GRB afterglows
We present the first high resolution (R=20000–45000, corresponding to 14 km/s at 4200Å to 6.6 km/s at 9000Å ) observations of the optical afterglow of Gamma Ray Bursts. GRB 020813 and GRB 021004 were observed by UVES@VLT 22.19 hours and 13.52 hours after the trigger, respectively. These spectra show that the inter–stellar matter of the GRB host galaxies is complex, with many components contribu...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2002