TY - JOUR
T1 - Detection of a thermal spectral component in the prompt emission of GRB 100724B
AU - Guiriec, Sylvain
AU - Connaughton, Valerie
AU - Briggs, Michael S.
AU - Burgess, Michael
AU - Ryde, Felix
AU - Daigne, Frédéric
AU - Mészáros, Peter
AU - Goldstein, Adam
AU - McEnery, Julie
AU - Omodei, Nicola
AU - Bhat, P. N.
AU - Bissaldi, Elisabetta
AU - Camero-Arranz, Ascensión
AU - Chaplin, Vandiver
AU - Diehl, Roland
AU - Fishman, Gerald
AU - Foley, Suzanne
AU - Gibby, Melissa
AU - Giles, Misty M.
AU - Greiner, Jochen
AU - Gruber, David
AU - Von Kienlin, Andreas
AU - Kippen, Marc
AU - Kouveliotou, Chryssa
AU - McBreen, Sheila
AU - Meegan, Charles A.
AU - Paciesas, William
AU - Preece, Robert
AU - Rau, Arne
AU - Tierney, Dave
AU - Van Der Horst, Alexander J.
AU - Wilson-Hodge, Colleen
PY - 2011/2/1
Y1 - 2011/2/1
N2 - Observations of GRB 100724B with the Fermi Gamma-Ray Burst Monitor find that the spectrum is dominated by the typical Band functional form, which is usually taken to represent a non-thermal emission component, but also includes a statistically highly significant thermal spectral contribution. The simultaneous observation of the thermal and non-thermal components allows us to confidently identify the two emission components. The fact that these seem to vary independently favors the idea that the thermal component is of photospheric origin while the dominant non-thermal emission occurs at larger radii. Our results imply either a very high efficiency for the non-thermal process or a very small size of the region at the base of the flow, both quite challenging for the standard fireball model. These problems are resolved if the jet is initially highly magnetized and has a substantial Poynting flux.
AB - Observations of GRB 100724B with the Fermi Gamma-Ray Burst Monitor find that the spectrum is dominated by the typical Band functional form, which is usually taken to represent a non-thermal emission component, but also includes a statistically highly significant thermal spectral contribution. The simultaneous observation of the thermal and non-thermal components allows us to confidently identify the two emission components. The fact that these seem to vary independently favors the idea that the thermal component is of photospheric origin while the dominant non-thermal emission occurs at larger radii. Our results imply either a very high efficiency for the non-thermal process or a very small size of the region at the base of the flow, both quite challenging for the standard fireball model. These problems are resolved if the jet is initially highly magnetized and has a substantial Poynting flux.
KW - Acceleration of particles
KW - Gamma rays: stars
KW - Gamma-ray burst: individual (GRB 1000724B)
KW - Radiation mechanisms: non-thermal
KW - Radiation mechanisms: thermal
UR - https://www.scopus.com/pages/publications/79960270885
U2 - 10.1088/2041-8205/727/2/L33
DO - 10.1088/2041-8205/727/2/L33
M3 - Article
AN - SCOPUS:79960270885
SN - 2041-8205
VL - 727
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 2 PART II
ER -