GRB 060605: multi-wavelength analysis of the first GRB observed using integral field spectroscopy
Ferrero, P.; Klose, S.; Kann, D. A.; Savaglio, S.;Schulze, S.; Palazzi, E.; Maiorano, E.; Böhm, P.;Grupe, D.; Oates, S. R.; Sánchez, S. F.; Amati, L.;Greiner, J.; Hjorth, J.; Malesani, D.;Barthelmy, S. D.; Gorosabel, J.; Masetti, N.;Roth, M. M.. GRB 060605: multi-wavelength analysis of the first GRB observed using integral field spectroscopy. Astronomy and Astrophysics. 2009, Vol. Volume 497, Issue 3, 2009, pp.729-741, p. -2009.
The long and relatively faint gamma-ray burst GRB 060605 detected by
Swift/BAT lasted about 20 s. Its afterglow could be observed with
Swift/XRT for nearly 1 day, while Swift/UVOT could detect the afterglow
during the first 6 h after the event. Here, we report on integral field
spectroscopy of its afterglow performed with PMAS/PPak mounted at the
Calar Alto 3.5 m telescope. In addition, we report on a detailed
analysis of XRT and UVOT data and on the results of deep late-time VLT
observations that reveal the GRB host galaxy. We find that the burst
occurred at a redshift of z = 3.773, possibly associated with a faint,
R<SUB>C</SUB> = 26.4 ± 0.3 host. Based on the optical and X-ray
data, we deduce information on the SED of the afterglow, the position of
the cooling frequency in the SED, the nature of the circumburst
environment, its collimation factor, and its energetics. We find that
the GRB fireball was expanding into a constant-density medium and that
the explosion was collimated with a narrow half-opening angle of about
2.4 degrees. The initial Lorentz factor of the fireball was about 250;
however, its beaming-corrected energy release in the gamma-ray band was
comparably low. The optical, X-ray afterglow, on the other hand, was
rather luminous. Finally, we find that the data are consistent within
the error bars with an achromatic evolution of the afterglow during the
suspected jet break time at about 0.27 days after the burst.
Based on observations collected at the German-Spanish Calar Alto
Observatory in Spain (Programme F06-3.5-055) and at the European
Southern Observatory, La Silla and Paranal, Chile (ESO Programme
177.D-0591).
The long and relatively faint gamma-ray burst GRB 060605 detected by
Swift/BAT lasted about 20 s. Its afterglow could be observed with
Swift/XRT for nearly 1 day, while Swift/UVOT could detect the afterglow
during the first 6 h after the event. Here, we report on integral field
spectroscopy of its afterglow performed with PMAS/PPak mounted at the
Calar Alto 3.5 m telescope. In addition, we report on a detailed
analysis of XRT and UVOT data and on the results of deep late-time VLT
observations that reveal the GRB host galaxy. We find that the burst
occurred at a redshift of z = 3.773, possibly associated with a faint,
R<SUB>C</SUB> = 26.4 ± 0.3 host. Based on the optical and X-ray
data, we deduce information on the SED of the afterglow, the position of
the cooling frequency in the SED, the nature of the circumburst
environment, its collimation factor, and its energetics. We find that
the GRB fireball was expanding into a constant-density medium and that
the explosion was collimated with a narrow half-opening angle of about
2.4 degrees. The initial Lorentz factor of the fireball was about 250;
however, its beaming-corrected energy release in the gamma-ray band was
comparably low. The optical, X-ray afterglow, on the other hand, was
rather luminous. Finally, we find that the data are consistent within
the error bars with an achromatic evolution of the afterglow during the
suspected jet break time at about 0.27 days after the burst.
Based on observations collected at the German-Spanish Calar Alto
Observatory in Spain (Programme F06-3.5-055) and at the European
Southern Observatory, La Silla and Paranal, Chile (ESO Programme
177.D-0591).