Multiple-component analysis of the time-resolved spectra of GRB 041006

A clue to the nature of the underlying soft component of GRBs

Yuji Shirasaki, Atsumasa Yoshida, Nobuyuki Kawai, Toru Tamagawa, Takanori Sakamoto, Motoko Suzuki, Yujin Nakagawa, Akina Kobayashi, Satoshi Sugita, Ichiro Takahashi, Makoto Arimoto, Takashi Shimokawabe, Nicolas Vasquez Pazmino, Takuto Ishimura, Rie Sato, Masaru Matsuoka, Edward E. Fenimore, Mark Galassi, Donald Q. Lamb, Carlo Graziani & 13 others Timothy Q. Donaghy, Jean Luc Atteia, Alexandre Pelangeon, Roland Vanderspek, Geoffrey B. Crew, John P. Doty, Joel Villasenor, Gregory Paigozhin, Nat Butler, George R. Ricker, Kevin Hurley, Stanford E. Woosley, Graziella Pizzichini

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

GRB 041006 was detected by HETE-2 on 2004 October 06. The light curves in four different energy bands display different features. At higher energy bands several peaks are seen in the light curve, while at lower energy bands a single broader bump dominates. It is expected that these different features are the result of a mixture of several components, each of which has different energetics and variability. We analyzed the time-resolved spectra, which were resolved into several components. These components can be classified into two distinct classes. One is a component that has an exponential decay of E p with a characteristic timescale shorter than ∼ 30s; its spectrum is well represented by a broken power-law function, which is frequently observed in many prompt GRB emissions, so it should have an internal-shock origin. Another is a component whose Ep is almost unchanged with a characteristic timescale longer than ∼ 60s, and shows a very soft emission and slower variability. The spectrum is characterized by either a broken power law or a black-body spectrum. By assuming that the soft component is a thermal emission, the radiation radius is initially 4.4 x 106km, which is a typical radius of a blue supergiant, and its expansion velocity is 2.4 x 10 5km s-1 in the source frame.

Original languageEnglish
Pages (from-to)919-931
Number of pages13
JournalPublications of the Astronomical Society of Japan
Volume60
Issue number4
Publication statusPublished - 2008
Externally publishedYes

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energy bands
power law
timescale
energy
light curve
radii
energetics
thermal emission
analysis
shock
expansion
decay
radiation

Keywords

  • Gamma-rays: Bursts
  • X-rays: individual (GRB 041006)
  • X-rays: nursts

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Shirasaki, Y., Yoshida, A., Kawai, N., Tamagawa, T., Sakamoto, T., Suzuki, M., ... Pizzichini, G. (2008). Multiple-component analysis of the time-resolved spectra of GRB 041006: A clue to the nature of the underlying soft component of GRBs. Publications of the Astronomical Society of Japan, 60(4), 919-931.

Multiple-component analysis of the time-resolved spectra of GRB 041006 : A clue to the nature of the underlying soft component of GRBs. / Shirasaki, Yuji; Yoshida, Atsumasa; Kawai, Nobuyuki; Tamagawa, Toru; Sakamoto, Takanori; Suzuki, Motoko; Nakagawa, Yujin; Kobayashi, Akina; Sugita, Satoshi; Takahashi, Ichiro; Arimoto, Makoto; Shimokawabe, Takashi; Pazmino, Nicolas Vasquez; Ishimura, Takuto; Sato, Rie; Matsuoka, Masaru; Fenimore, Edward E.; Galassi, Mark; Lamb, Donald Q.; Graziani, Carlo; Donaghy, Timothy Q.; Atteia, Jean Luc; Pelangeon, Alexandre; Vanderspek, Roland; Crew, Geoffrey B.; Doty, John P.; Villasenor, Joel; Paigozhin, Gregory; Butler, Nat; Ricker, George R.; Hurley, Kevin; Woosley, Stanford E.; Pizzichini, Graziella.

In: Publications of the Astronomical Society of Japan, Vol. 60, No. 4, 2008, p. 919-931.

Research output: Contribution to journalArticle

Shirasaki, Y, Yoshida, A, Kawai, N, Tamagawa, T, Sakamoto, T, Suzuki, M, Nakagawa, Y, Kobayashi, A, Sugita, S, Takahashi, I, Arimoto, M, Shimokawabe, T, Pazmino, NV, Ishimura, T, Sato, R, Matsuoka, M, Fenimore, EE, Galassi, M, Lamb, DQ, Graziani, C, Donaghy, TQ, Atteia, JL, Pelangeon, A, Vanderspek, R, Crew, GB, Doty, JP, Villasenor, J, Paigozhin, G, Butler, N, Ricker, GR, Hurley, K, Woosley, SE & Pizzichini, G 2008, 'Multiple-component analysis of the time-resolved spectra of GRB 041006: A clue to the nature of the underlying soft component of GRBs', Publications of the Astronomical Society of Japan, vol. 60, no. 4, pp. 919-931.
Shirasaki, Yuji ; Yoshida, Atsumasa ; Kawai, Nobuyuki ; Tamagawa, Toru ; Sakamoto, Takanori ; Suzuki, Motoko ; Nakagawa, Yujin ; Kobayashi, Akina ; Sugita, Satoshi ; Takahashi, Ichiro ; Arimoto, Makoto ; Shimokawabe, Takashi ; Pazmino, Nicolas Vasquez ; Ishimura, Takuto ; Sato, Rie ; Matsuoka, Masaru ; Fenimore, Edward E. ; Galassi, Mark ; Lamb, Donald Q. ; Graziani, Carlo ; Donaghy, Timothy Q. ; Atteia, Jean Luc ; Pelangeon, Alexandre ; Vanderspek, Roland ; Crew, Geoffrey B. ; Doty, John P. ; Villasenor, Joel ; Paigozhin, Gregory ; Butler, Nat ; Ricker, George R. ; Hurley, Kevin ; Woosley, Stanford E. ; Pizzichini, Graziella. / Multiple-component analysis of the time-resolved spectra of GRB 041006 : A clue to the nature of the underlying soft component of GRBs. In: Publications of the Astronomical Society of Japan. 2008 ; Vol. 60, No. 4. pp. 919-931.
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AU - Shirasaki, Yuji

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AU - Kawai, Nobuyuki

AU - Tamagawa, Toru

AU - Sakamoto, Takanori

AU - Suzuki, Motoko

AU - Nakagawa, Yujin

AU - Kobayashi, Akina

AU - Sugita, Satoshi

AU - Takahashi, Ichiro

AU - Arimoto, Makoto

AU - Shimokawabe, Takashi

AU - Pazmino, Nicolas Vasquez

AU - Ishimura, Takuto

AU - Sato, Rie

AU - Matsuoka, Masaru

AU - Fenimore, Edward E.

AU - Galassi, Mark

AU - Lamb, Donald Q.

AU - Graziani, Carlo

AU - Donaghy, Timothy Q.

AU - Atteia, Jean Luc

AU - Pelangeon, Alexandre

AU - Vanderspek, Roland

AU - Crew, Geoffrey B.

AU - Doty, John P.

AU - Villasenor, Joel

AU - Paigozhin, Gregory

AU - Butler, Nat

AU - Ricker, George R.

AU - Hurley, Kevin

AU - Woosley, Stanford E.

AU - Pizzichini, Graziella

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KW - Gamma-rays: Bursts

KW - X-rays: individual (GRB 041006)

KW - X-rays: nursts

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