Charles A. Meegan

University of Alabama in Huntsville

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W. S. Pačiesas

Universities Space Research Association

107

M. S. Briggs

University of Alabama in Huntsville

C. Kouveliotou

George Washington University

G. J. Fishman

Marshall Space Flight Center

Geoffrey N. Pendleton

DeciBel Research (United States)

R. D. Preece

University of Alabama in Huntsville

V. Connaughton

Universities Space Research Association

C. Wilson‐Hodge

Marshall Space Flight Center

A. von Kienlin

Max Planck Institute for Extraterrestrial Physics

J. Greiner

Max Planck Institute for Extraterrestrial Physics

Cooperative Institutions

Marshall Space Flight Center

Goddard Space Flight Center

Universities Space Research Association

University of Alabama in Huntsville

Max Planck Institute for Extraterrestrial Physics

Los Alamos National Laboratory

National Space Science and Technology Center

University of Maryland, Baltimore County

Max Planck Society

Deleted Institution

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Fermi/GAMMA-RAY BURST MONITOR OBSERVATIONS OF SGR J0501+4516 BURSTS

The Astrophysical Journal (2011)

Lin Lın C. Kouveliotou Matthew G. Baring A. J. van der Horst S. Guiriec

We present our temporal and spectral analyses of 29 bursts from SGR J0501+4516, detected with the gamma-ray burst monitor on board the Fermi Gamma-ray Space Telescope during 13 days of the source's activation in 2008 (August 22– September 3). We find that the T90 durations of the bursts can be fit with a log-normal distribution with a mean value of ∼123 ms. We also estimate for the first time event durations of soft gamma repeater (SGR) bursts in photon space (i.e., using their deconvolved spectra) and find that these are very similar to the T90 values estimated in count space (following a log-normal distribution with a mean value of ∼124 ms). We fit the time-integrated spectra for each burst and the time-resolved spectra of the five brightest bursts with several models. We find that a single power law with an exponential cutoff model fits all 29 bursts well, while 18 of the events can also be fit with two blackbody functions. We expand on the physical interpretation of these two models and we compare their parameters and discuss their evolution. We show that the time-integrated and time-resolved spectra reveal that Epeak decreases with energy flux (and fluence) to a minimum of ∼30 keV at F = 8.7 × 10−6 erg cm−2 s−1, increasing steadily afterward. Two more sources exhibit a similar trend: SGRs J1550–5418 and 1806–20. The isotropic luminosity, Liso, corresponding to these flux values is roughly similar for all sources (0.4–1.5 × 1040 erg s−1).

Black-body radiation

Cut-off

Magnetar

Spitzer Space Telescope

10.1088/0004-637x/739/2/87

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Citations (43)

Thefermigbm Gamma-Ray Burst Catalog: The First Two Years

W. S. Pačiesas Charles A. Meegan A. von Kienlin P. N. Bhat E. Bissaldi

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Cross calibration of burst spectra with BATSE, EGRET, and COMPTEL for GRB910503

AIP conference proceedings (1994)

Bradley E. Schaefer B. Teegarden T. Cline B. L. Dingus G. J. Fishman

Nine photon spectra for GRB910503 from BATSE, EGRET, and COMPTEL are extracted and compared. We find that all spectra agree well with each other. In addition, we present a composite spectrum from 20 keV to 200 MeV.

Optical spectra

10.1063/1.45879

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Citations (3)

FIRST-YEAR RESULTS OF BROADBAND SPECTROSCOPY OF THE BRIGHTESTFERMI-GBM GAMMA-RAY BURSTS

The Astrophysical Journal (2011)

E. Bissaldi A. von Kienlin C. Kouveliotou M. S. Briggs V. Connaughton

We present our results of the temporal and spectral analysis of a sample of 52 bright and hard gamma-ray bursts (GRBs) observed with the Fermi Gamma-ray Burst Monitor (GBM) during its first year of operation (2008 July–2009 July).Our sample was selected from a total of 253 GBM GRBs based on the event peak count rate measured between 0.2 and 40 MeV. The final sample comprised of 34 long and 18 short GRBs. These numbers show that the GBM sample contains a much larger fraction of short GRBs than the CGRO/BATSE data set, which we explain as the result of our (different) selection criteria, which favor collection of short, bright GRBs over BATSE. A first by-product of our selection methodology is the determination of a detection threshold from the GBM data alone, above which GRBs most likely will be detected in the MeV/GeV range with the Large Area Telescope on board Fermi. This predictor will be very useful for future multi-wavelength GRB follow-ups with ground- and space-based observatories. Further, we have estimated the burst durations up to 10 MeV and for the first time expanded the duration–energy relationship in the GRB light curves to high energies. We confirm that GRB durations decline with energy as a power law with index approximately −0.4, as was found earlier with the BATSE data and we also notice evidence of a possible cutoff or break at higher energies. Finally, we performed time-integrated spectral analysis of all 52 bursts and compared their spectral parameters with those obtained with the larger data sample of the BATSE data. We find that the two parameter data sets are similar and confirm that short GRBs are in general harder than longer ones.

Sample (material)

10.1088/0004-637x/733/2/97

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Citations (26)

A Balloon-Borne Gamma-Ray Polarimeter for Gamma-Ray Bursts

AIP conference proceedings (2009)

M. L. McConnell Christopher M. Bancroft Peter F. Bloser Taylor Connor Jason Legere

We have developed a design for a hard X‐ray polarimeter operating in the energy range from 50 to 500 keV. This modular design, known as GRAPE (Gamma‐Ray Polarimeter Experiment), was successfully demonstrated with partially polarized gamma‐ray sources in the lab and fully polarized photon beams at Argonne National Laboratory. In June of 2007, a GRAPE engineering model flew on a high altitude balloon flight which demonstrated the design and collected background data. A much larger payload is currently under development that will provide a significant level of sensitivity for gamma‐ray bursts on a long‐duration balloon flight. The first balloon flight of the full GRAPE instrument is currently scheduled to take place in the Fall of 2011 from Ft. Sumner, NM.

Polarimeter

Payload (computing)

Gamma-Ray Astronomy

10.1063/1.3155968

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Citations (3)

GAMMA-RAY BURST: Sixth Huntsville Symposium

AIPC (2009)

Charles A. Meegan C. Kouveliotou N. Gehrels

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Citations (44)

Searches for neutrinos from GRBs with IceCube

AIP conference proceedings (2009)

I. Taboada Charles A. Meegan C. Kouveliotou N. Gehrels

Forty years ago it was recognized that the detection of high energy (≳TeV) neutrinos from astronomical sources would require the construction of a device with 1 gigaton (or 1 cubic kilometer of ice) of target material. This idea is now becoming a reality at the South Pole with the construction of IceCube. Detection of extraterrestrial high energy neutrinos will open new avenues in astrophysics and neutrino physics. A positive observation of neutrinos in coincidence with a GRB would identify these objects as one the source of the highest energy cosmic rays and would provide invaluable information about the processes responsible for GRBs.In this paper I summarize the results from searches for neutrinos from GRBs with IceCube and its predecessor, AMANDA. I review the status of the construction and operation of IceCube. Finally, I outline future directions for IceCube, in particular in searches of neutrinos from GRBs reported by Fermi.

Neutrino astronomy

Extraterrestrial Life

Cosmic neutrino background

High energy

10.1063/1.3155942

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Citations (0)

Experimental Astronomy (1997)

R. Hudec P. Spurný J. Florián J. Boček M. Tichý

Variable star

10.1023/a:1007933102971

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Average Cosmological Invariant Parameters of Cosmic Gamma‐Ray Bursts

The Astrophysical Journal (1999)

И. Г. Митрофанов D. Anfimov M. L. Litvak M. S. Briggs W. S. Pačiesas

Average cosmological invariant parameters (ACIPs) are calculated for six groups of BATSE cosmic gamma-ray bursts selected by their peak fluxes on the 1.024 s timescale. The ACIPs represent the average temporal and spectral properties of these events equally in the observer frame of reference and in the comoving frames of outbursting emitters. The parameters are determined separately for rise fronts and for back slopes of bursts, defined as the time profiles before and after the main peaks, respectively. The ACIPs for the rise fronts are found to be different for different intensity groups, while the ACIPs for the back slopes show no significant dependence on intensity. We conclude that emitters of bursts manifest standard average properties only during the back slopes of bursts.

Observer (physics)

Intensity

10.1086/307709

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Citations (2)

Balloon-borne measurements of the SN 1987A hard X-ray continuum

The Astrophysical Journal (1995)

Geoffrey N. Pendleton W. S. Pačiesas G. J. Fishman Charles A. Meegan Robert Wilson

view Abstract Citations (6) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Balloon-borne Measurements of the SN 1987A Hard X-Ray Continuum Pendleton, Geoffrey N. ; Paciesas, William S. ; Fishman, Gerald J. ; Meegan, Charles A. ; Wilson, Robert B. Abstract SN 1987A hard X-ray continuum spectra obtained on 1987 October 29, 1988 April 9-10, and 1988 November 11 from balloon-flight measurements are presented. The spectra, spanning the energy range from 25 keV to 300 keV, have been analyzed using a detector response matrix inversion technique that converts the spectra from counts s^-1^ cm^2^ keV to photons s^-1^ cm^2^ keV allowing direct comparison with theoretical models. The results indicate that the bulk of the ^56^Co is mixed moderately through the inner regions of the supernova envelope but they do not preclude the mixing of a small amount of the ^56^Co farther out into the envelope necessary to account for the observed ^56^Co line fluxes. The effect of the ratio ^57^Co to ^56^Co on the 1988 November 11 continuum spectrum is discussed. Publication: The Astrophysical Journal Pub Date: February 1995 DOI: 10.1086/175233 Bibcode: 1995ApJ...439..963P Keywords: Balloon-Borne Instruments; Continuous Spectra; Gamma Rays; Supernova 1987a; X Ray Spectra; Carbon Monoxide; Photomultiplier Tubes; Scintillation Counters; Spectrum Analysis; Astrophysics; BALLOONS; GAMMA RAYS: OBSERVATIONS; STARS: SUPERNOVAE: INDIVIDUAL ALPHANUMERIC: SN 1987A; X-RAYS: STARS full text sources ADS | data products SIMBAD (6) NED (2)

10.1086/175233

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Citations (7)