NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Low-resolution VLT Spectroscopy of GRBs 991216, 011211, 021211 and 030328We present low-resolution VLT spectroscopy of the aftergiow position of the gamma ray bursts 991216, 011211, 021211 and 030328. The spectmm of GRB 991216 shows two probable absorption systems at z = 0.80 and z = 1.02, where the highest redshift most likely reflects the distance to the host galaxy. A third, more uncertain, system may be detected at z = 0.77. HST imaging of the field obtained 4 months later, show two amorphous regions of emission, one at the projected OT position, the presumed host galaxy at z = 1.02, and the other 0"6 away. All significant lines in the spectrum of GRB 011211 are identified with lines originating in a single absorption system at z = 2.142 plus or minus 0.002, the redshift of the GRB 011211 host galaxy. We also detect Lya in the host, for which we fit a neutral hydrogen column density of log N(HI)=20.4 plus or minus 0.2, which indicates that it is a damped Lya system. For GRB021211, we detect a single emission line in a spectrum tens of days after the burst, which we identify as [OII] at z = 1.006. The galaxy l"5 away from the afterglow location has z = 0.800, and is therefore unrelated to the GRB. Finally, for GRB030328 at least two absorption systems are required to explain all significant lines: one at z = 1.522, the likely redshift of the GRB, and the other at z = 1.295. For the latter system we only detect two lines, and we consider the reality of this system to be uncertain.
Document ID
20050092392
Acquisition Source
Marshall Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
Vreeswijk, P. M.
(European Southern Observatory Santiago, Chile)
Smette, A.
(Liege Univ. Belgium)
Fruchter, A. S.
(Space Telescope Science Inst. Baltimore, MD, United States)
Palazzi, E.
(Consiglio Nazionale delle Ricerche Bologna, Italy)
Rol, E.
(European Southern Observatory Santiago, Chile)
Wijers, R. A. M. J.
(State Univ. of New York Stony Brook, NY, United States)
Kouveliotou, C.
(NASA Marshall Space Flight Center Huntsville, AL, United States)
Kaper, L.
(European Southern Observatory Santiago, Chile)
Pian, E.
(Consiglio Nazionale delle Ricerche Bologna, Italy)
Masetti, N.
(Consiglio Nazionale delle Ricerche Bologna, Italy)
Date Acquired
August 22, 2013
Publication Date
January 1, 2005
Subject Category
Astronomy
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available