Abstract
We analyze Swift gamma-ray bursts (GRBs) and X-ray afterglows for three GRBs with spectroscopic redshift determinations - GRB 050401, XRF 050416a, and GRB 050525a. We find that the relation between spectral peak energy and isotropic energy of prompt emissions (the Amati relation) is consistent with that for the bursts observed in pre-Swift era. However, we find that the X-ray afterglow lightcurves, which extend up to 10-70 days, show no sign of the jet break that is expected in the standard framework of collimated outflows. We do so by showing that none of the X-ray afterglow lightcurves in our sample satisfies the relation between the spectral and temporal indices that is predicted for the phase after jet break. The jet break time can be predicted by inverting the tight empirical relation between the peak energy of the spectrum and the collimation-corrected energy of the prompt emission (the Ghirlanda relation). We find that there are no temporal breaks within the predicted time intervals in X-ray band. This requires either that the Ghirlanda relation has a larger scatter than previously thought, that the temporal break in X-rays is masked by some additional source of X-ray emission, or that it does not happen because of some unknown reason.
| Original language | English |
|---|---|
| Title of host publication | 11th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation and Relativistic Field Theories - Proc. of the MG11 Meeting on General Relativity |
| Pages | 2033-2035 |
| Number of pages | 3 |
| Publication status | Published - 2008 |
| Event | 11th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation and Relativistic Field Theories, MG 2006 - Berlin Duration: 2006 Jul 23 → 2006 Jul 29 |
Other
| Other | 11th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation and Relativistic Field Theories, MG 2006 |
|---|---|
| City | Berlin |
| Period | 06/7/23 → 06/7/29 |
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ASJC Scopus subject areas
- Nuclear and High Energy Physics
Cite this
Investigation of jet break features in Swift gamma-ray bursts. / Sato, G.; Yamazaki, R.; Ioka, K.; Sakamoto, T.; Takahashi, T.; Nakazawa, K.; Nakamura, T.; Toma, K.; Hullinger, D.; Tashiro, M.; Parsons, A. M.; Krimm, H. A.; Barthelmy, S. D.; Gehrels, N.; Burrows, D. N.; O'Brien, P. T.; Osborne, J. P.; Chincarini, G.; Lamb, D. Q.
11th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation and Relativistic Field Theories - Proc. of the MG11 Meeting on General Relativity. 2008. p. 2033-2035.Research output: Chapter in Book/Report/Conference proceeding › Conference contribution
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TY - GEN
T1 - Investigation of jet break features in Swift gamma-ray bursts
AU - Sato, G.
AU - Yamazaki, R.
AU - Ioka, K.
AU - Sakamoto, T.
AU - Takahashi, T.
AU - Nakazawa, K.
AU - Nakamura, T.
AU - Toma, K.
AU - Hullinger, D.
AU - Tashiro, M.
AU - Parsons, A. M.
AU - Krimm, H. A.
AU - Barthelmy, S. D.
AU - Gehrels, N.
AU - Burrows, D. N.
AU - O'Brien, P. T.
AU - Osborne, J. P.
AU - Chincarini, G.
AU - Lamb, D. Q.
PY - 2008
Y1 - 2008
N2 - We analyze Swift gamma-ray bursts (GRBs) and X-ray afterglows for three GRBs with spectroscopic redshift determinations - GRB 050401, XRF 050416a, and GRB 050525a. We find that the relation between spectral peak energy and isotropic energy of prompt emissions (the Amati relation) is consistent with that for the bursts observed in pre-Swift era. However, we find that the X-ray afterglow lightcurves, which extend up to 10-70 days, show no sign of the jet break that is expected in the standard framework of collimated outflows. We do so by showing that none of the X-ray afterglow lightcurves in our sample satisfies the relation between the spectral and temporal indices that is predicted for the phase after jet break. The jet break time can be predicted by inverting the tight empirical relation between the peak energy of the spectrum and the collimation-corrected energy of the prompt emission (the Ghirlanda relation). We find that there are no temporal breaks within the predicted time intervals in X-ray band. This requires either that the Ghirlanda relation has a larger scatter than previously thought, that the temporal break in X-rays is masked by some additional source of X-ray emission, or that it does not happen because of some unknown reason.
AB - We analyze Swift gamma-ray bursts (GRBs) and X-ray afterglows for three GRBs with spectroscopic redshift determinations - GRB 050401, XRF 050416a, and GRB 050525a. We find that the relation between spectral peak energy and isotropic energy of prompt emissions (the Amati relation) is consistent with that for the bursts observed in pre-Swift era. However, we find that the X-ray afterglow lightcurves, which extend up to 10-70 days, show no sign of the jet break that is expected in the standard framework of collimated outflows. We do so by showing that none of the X-ray afterglow lightcurves in our sample satisfies the relation between the spectral and temporal indices that is predicted for the phase after jet break. The jet break time can be predicted by inverting the tight empirical relation between the peak energy of the spectrum and the collimation-corrected energy of the prompt emission (the Ghirlanda relation). We find that there are no temporal breaks within the predicted time intervals in X-ray band. This requires either that the Ghirlanda relation has a larger scatter than previously thought, that the temporal break in X-rays is masked by some additional source of X-ray emission, or that it does not happen because of some unknown reason.
UR - http://www.scopus.com/inward/record.url?scp=84892974067&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84892974067&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:84892974067
SN - 9812834265
SN - 9789812834263
SP - 2033
EP - 2035
BT - 11th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation and Relativistic Field Theories - Proc. of the MG11 Meeting on General Relativity
ER -