HAPPY BIRTHDAY SWIFT: ULTRA-LONG GRB 141121A AND ITS BROADBAND AFTERGLOW

Journal Article · Tue Oct 20 00:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/812/2/122· OSTI ID:22518786

Cucchiara, A. ^[1]; Veres, P. ^[2]; Corsi, A. ^[3]; Cenko, S. B.; Marshall, F. E.; Kutyrev, A. S. ^[4]; Perley, D. A.; Horesh, A. ^[5]; Lien, A. ^[6]; Pagani, C. ^[7]; Toy, V. L.; Capone, J. I. ^[8]; Frail, D. A. ^[9]; Modjaz, M. ^[10]; Butler, N. R.; Littlejohns, O. M. ^[11]; Watson, A. M.; Lee, W. H.; Richer, M. G. ^[12]; others, and

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1. Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
2. The George Washington University, Department of Physics, 725 21st, NW Washington, DC 20052 (United States)
3. Physics Department, Texas Tech University, Box 41051, Lubbock, TX 79409 (United States)
4. Astrophysics Science Division, NASA Goddard Space Flight Center, MC 661, Greenbelt, MD 20771 (United States)
5. Department of Astronomy, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
6. Center for Research and Exploration in Space Science and Technology (CRESST) and NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
7. Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)
8. Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)
9. National Radio Astronomy Observatory P.O. Box 0. Socorro, NM (United States)
10. Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)
11. School of Earth and Space Exploration, Arizona State University, AZ 85287 (United States)
12. Instituto de Astronomía, Universidad Nacional Autónoma de México, Apartado Postal 70-264, 04510 México, D. F., México (Mexico)

We present our extensive observational campaign on the Swift-discovered GRB 141121A, almost 10 years after its launch. Our observations cover radio through X-rays and extend for more than 30 days after discovery. The prompt phase of GRB 141121A lasted 1410 s and, at the derived redshift of z = 1.469, the isotropic energy is E{sub γ,iso} = 8.0 × 10{sup 52} erg. Due to the long prompt duration, GRB 141121A falls into the recently discovered class of ultra-long GRBs (UL-GRBs). Peculiar features of this burst are (1) a flat early-time optical light curve and (2) a radio-to-X-ray rebrightening around three days after the burst. The latter is followed by a steep optical-to-X-ray decay and a much shallower radio fading. We analyze GRB 141121A in the context of the standard forward–reverse shock (FS, RS) scenario and we disentangle the FS and RS contributions. Finally, we comment on the puzzling early-time (t ≲ 3 days) behavior of GRB 141121A, and suggest that its interpretation may require a two-component jet model. Overall, our analysis confirms that the class of UL-GRBs represents our best opportunity to firmly establish the prominent emission mechanisms in action during powerful gamma-ray burst explosions, and future missions (like SVOM, XTiDE, or ISS-Lobster) will provide many more of such objects.

• OSTI ID: 22518786
• Journal Information: Astrophysical Journal, Vol. 812, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
AFTERGLOW
COSMIC GAMMA BURSTS
COSMIC RADIO SOURCES
DIAGRAMS
RED SHIFT
VISIBLE RADIATION