BATSE Rapid Response Network

The need for rapid and accurate gamma-ray burst locations has long been recognized as the fundamental key to solving the gamma-ray burst (GRB) counterpart problem. However, its realization has been technically difficult to achieve. For the past four years the BACODINE system has been attempting to solve this problem by providing roughly-determined (accurate to ~4 deg, at best) BATSE burst locations in near real-time (typically a few seconds) to a network of dedicated optical/radio counterpart searchers. The BACODINE system sacrifices location accuracy in favor of speed in its use of small amounts of data, automated background estimation and simplified location algorithm. Unfortunately, BACODINE locations are too imprecise to allow for the sensitive observations now known to be required to detect faint GRB afterglows.

To facilitate more sensitive counterpart searches on somewhat longer timescales we have developed the BATSE Rapid Burst Response (RBR) system, that takes the opposite approach from BACODINE: better location accuracy at the cost of longer delay. This is accomplished using more data, human background estimation and a more detailed location algorithm (LOCBURST). The improved BATSE RBR locations have a typical accuracy of ~2 deg (68% containment radius), with a post-burst delay of ~10-30 minutes. The RBR system operates in parallel with normal BACODINE processing and the locations from both systems are distributed via the same, well-established, GCN/BACODINE network.

SYSTEM OPERATION

The following diagram illustrates the operation of the BATSE RBR system from the detection of a burst by BATSE on-board software to the computation and dissemation of the burst location through the Gamma-Ray Coordinates Network (GCN). While data downloading and location dissemenation are automated, human operators are a valuable part of the procedure for estimation of source/ background time-intervals and efficient rejection of non-GRB triggers.

Schematic of RBR

LOCATION ERRORS

While the BATSE RBR system uses the same LOCBURST algorithm employed for all "best-and-final" BATSE burst locations, it cannot make use of the full BATSE dataset (most burst data are stored in memory and are thus not available in the real-time telemetry at the time of a burst). We have therefore independently assessed the location errors from the BATSE RBR system. As a comparison sample, we use 70 of the most recent bursts located to single annuli by BATSE/Ulysses IPN timing analysis. The shortest angular separation rho between BATSE locations and IPN annuli yields a statistical estimate of the total BATSE location error (a combination of measured statistical error and an unknown systematic contribution).

GBM-IPN location separation

The following figure shows the cumulative distribution of BATSE-RBR/IPN separations. The procedure has been repeated for the BACODINE locations and the official BATSE locations from the 4B catalog. It is evident that the BATSE RBR locations are consistent with the 4B locations, whereas they are significantly more accurate (factor of ~3, on average) than BACODINE.

Cumulative location error distribution

Through Monte Carlo simulations, we have found that a constant systematic error of ~2 deg is required in addition to the measured statistical errors to explain the BATSE RBR/IPN distribution. The following table shows the fraction of BATSE RBR bursts expected as a function of total location error (assuming 2 deg systematic error).

Table showing 
error distribution

A more detailed analysis of the BATSE-RBR location errors is explained in a paper presented at the 4th Huntsville GRB symposium. Follow THIS LINK to read a web-version of the paper, or go back to the RBR home page and select "publications" to download a printable version.

This link to GCN lists all recent BATSE triggers (updated in real-time). Triggers indicated by type=LOCBURST have been localized by the BATSE RBR system. Burst location coordinates and (in many cases) BATSE lightcurves can be downloaded from this site.

Notable bursts detected with the BATSE RBR system.

Burst lightcurves and location "finding" maps for notable bursts are provided below in viewable GIF and printable PS formats.

Some of these events were scanned by the Proportional Counter Array (PCA; 2-10 keV) instrument on the Rossi X-ray Timing Explorer (RXTE) in an attempt to detect fading x-ray afterglow emission. Links to current GCN notices for these bursts are provided.

The remaining events are notable for other reasons, as indicated.

Burst Trigger Sky-Map LightcurveComments
GRB_000307 8022 GIF PS GIF PS Detected by Konus, Ulysses, and NEAR
GRB_000210 n/a GIF PS GIF PS Untriggered burst detected by SAX-WFC, Konus, Ulysses, and Chandra.
GRB_000115 7954 GIF PS GIF PS Fading x-ray source detectected by RXTE-PCA!! (See GCN Notice). Detected by Konus and NEAR.
GRB_991216 7906 GIF PS GIF PS Very large BATSE burst. Fading x-ray source detectected by RXTE-PCA!! (See GCN Notice). Optical transient discovered!! Detected by Ulysses and NEAR.
GRB_991127 7884 GIF PS GIF PS Detected by Ulysses.
GRB_991115 7858 GIF PS GIF PS Detected by Ulysses.
GRB_991014 7803 GIF PS GIF PS Detected by SAX & Ulysses.
GRB_990915 7766 GIF PS GIF PS Detected by COMPTEL & Ulysses.
GRB_990806 7701 GIF PS GIF PS Detected by SAX-WFC, NFI; scanned by XTE-PCA.
GRB_990728 7678 GIF PS GIF PS Detected by COMPTEL.
GRB_990625 7619 GIF PS GIF PS Detected by SAX-WFC.
GRB_990615 7607 GIF PS GIF PS Location scanned by RXTE-PCA; Detected by Ulysses.
GRB_990518 7575 GIF PS GIF PS Detected by Ulysses.
GRB_990510 7560 GIF PS GIF PS Detected by SAX-WFC.
GRB_990506 7549 GIF PS GIF PS Fading x-ray source detectected by RXTE-PCA!! (See GCN Notice).Detected by Ulysses.
GRB_990505 7548 GIF PS GIF PS Detected by Ulysses.
GRB_990425 7530 GIF PS GIF PS Detected by Ulysses.
GRB_990424b 7529 GIF PS GIF PS Detected by Ulysses.
GRB_990424a 7527 GIF PS GIF PS Detected by Ulysses.
GRB_990403 7503 GIF PS GIF PS Detected by Ulysses.
GRB_990323 7491 GIF PS GIF PS Detected by Ulysses, NEAR.
GRB_990316 7475 GIF PS GIF PS Imaged in optical, detected by Ulysses.
GRB_990311 7464 GIF PS GIF PS Detected by Ulysses.
GRB_990308 7457 GIF PS GIF PS Detected by RXTE-ASM, Ulysses.
GRB_990304 7446 GIF PS GIF PS Detected by Ulysses.
GRB_990123 7343 GIF PS GIF PS Detected by SAX, COMPTEL.
GRB_990111 7319 GIF PS GIF PS Detected by Ulysses.
GRB_981223 7277 GIF PS GIF PS Location scanned by RXTE-PCA (See GCN Notice).Detected by Ulysses.
GRB_981205 7250 GIF PS GIF PS Detected by Ulysses.
GRB_981130 7240 GIF PS GIF PS Detected by Ulysses.
GRB_980923 7113 GIF PS GIF PS Very bright; location scanned by RXTE-PCA (See GCN Notice).
GRB_980810 6985 GIF PS GIF PS Detected by Ulysses.
GRB_980706 6904 GIF PS GIF PS Location scanned by RXTE-PCA; detected by COMPTEL and Ulysses. (See GCN Notice)
GRB_980703 6891 GIF PS GIF PS Detected by RXTE-ASM, BeppoSAX-NFI, and Ulysses. Optical transient detected.
GRB_980611 6816 GIF PS GIF PS Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_980519 6764 GIF PS GIF PS Localized by SAX-WFC, SAX-NFI; optical transient detected; detected by Ulysses
GRB_980425 6707 GIF PS GIF PS Localized by SAX-WFC, SAX-NFI; possible optical transient
GRB_980401 6672 GIF PS GIF PS Detected by Ulysses
GRB_980329 6665 GIF PS GIF PS Localized by COMPTEL, SAX-WFC, SAX-NFI, Ulysses (see IAUC).
GRB_980326 6660 GIF PS GIF PS Localized by SAX-WFC; detected by Ulysses; optical transient detected (see IAUC).
GRB_980306 6630 GIF PS GIF PS Detected by Ulysses
GRB_980208 6593 GIF PS GIF PS Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_980203 6587 GIF PS GIF PS Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_980125 6581 GIF PS GIF PS Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_980124 6576 GIF PS GIF PS Detected by CGRO-COMPTEL and Ulysses
GRB_980109 6564 GIF PS GIF PS Detected by SAX-WFC
GRB_971227 6546 GIF PS GIF PS Detected by SAX-WFC, SAX-NFI (see IAUC).
GRB_971214 6533 GIF PS GIF PS Detected by RXTE-ASM, SAX-WFC, SAX-NFI, and Ulysses (see IAUC).
GRB_971212 6531 GIF PS GIF PS The 2000th GRB detected by BATSE!
GRB_971210 6528 GIF PS GIF PS Detected by Ulysses.
GRB_971209 6527 GIF PS GIF PS Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_971208 6526 GIF PS GIF PS The longest, smoothest single GRB episode ever observed by BATSE (see IAUC); also detected by Ulysses.
GRB_971113 6476 GIF PS GIF PS Location scanned by RXTE-PCA (See GCN Notice)
GRB_970925 6397 GIF PS GIF PS Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_970807 6329 GIF PS n/a n/a Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_970704 6293 GIF PS n/a n/a Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_970616 6274 GIF PS n/a n/a Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
GRB_970603 6251 GIF PS n/a n/a Location scanned by RXTE-PCA (See GCN Notice); detected by Ulysses
Gamma-Ray Burst Astronomy and Instrumentation
Compton Gamma Ray Observatory
BATSE (Burst and Transient Source Experiment)
BATSE Home Page at MSFC
GCN/BACODINE
COMPTEL (Compton Telescope)
COMPTEL Gamma-Ray Burst Page
EGRET (Energetic Gamma-Ray Experiment Telescope)
OSSE (Oriented Scintillation Spectrometer Experiment)

HETE - High-Energy Transient Experiment
HETE at MIT
HETE at LANL
BeppoSAX Science Data Center
Rossi XTE Guest Observer Facility
TGRS
ASCA
CATSAT
MILAGRO
INTEGRAL
SiliconGLAST
Detector development at NRL

Related Places
NASA
Marshall Space Flight Center
Space Sciences Laboratory
Gamma-Ray Astronomy
Goddard Space Flight Center
Laboratory for High-Energy Astrophysics
The University of Alabama in Huntsville
Center for Space Plasma, Aeronomic and Astrophysics Research
Physics Department

Information Resources
High-Energy Astrophysics Science Archive Research Center
Astrophysics Data System Abstracts Service
LANL Astrophysics Preprint Server
Astrophysical Journal Electronic Edition
Nature
Astronomy Picture of the Day

Scientific Organizations
AAS - American Astronomical Society
High-Energy Astrophysics Division
SPIE - The International Society for Optical Engineering
APS - The American Physical Society
SigmaXi - The Scientific Research Society

Journal Publications (including IAU Circulars)

The following is a list of journal publications related to the BATSE Rapid Burst Response Effort. Postscript versions of some papers may be downloaded by selecting the word "postscript". Select the paper title to read the full abstract and author list.

  1. RXTE Observations of GRB Afterglows, Marshall, F. E., et al., 1998. Nucl. Phys. B 69, 640-645
  2. GRB 980326 & GRB 980329, Briggs et al., 1997. IAU Circ. 6856
  3. GRB 971227, Woods et al., 1997. IAU Circ. 6798
  4. GRB 971214, Kippen et al., 1997. IAU Circ. 6789
  5. GRB 971208, Connaughton et al., 1997. IAU Circ. 6785
  6. GRB 970616, Connaughton et al., 1997. IAU Circ. 6683
  7. GRB 970616, Marshall et al., 1997. IAU Circ. 6683

Conference Presentations (including proceedings articles)
The following is a list of conference presentations related to the BATSE Rapid Burst Response effort. Postscript versions of some articles may be downloaded by selecting the word "postscript". Select the article title to read the full abstract and author list.

  1. Conference on Cosmic Explosions (College Park, MD, October, 1999)
    1. Detection of Decaying X-Ray Afterglow of GRB 990506 with RXTE/PCA, Takeshima, T., et al., 1999.

  2. 4th Huntsville Gamma Ray Burst Symposium (Huntsville, AL, September, 1997)
    1. The BATSE Rapid Burst Response System, Kippen et al., 1997. [HTML version] or [PS version]
    2. RXTE Quick Response Observations of Afterglows from GRBs, Takeshima et al., 1997.

  3. 190th Meeting of the AAS (Winston-Salem, NC, June, 1997)
    1. Rapid Follow-Up Gamma-Ray Burst Locations from BATSE, Kippen et al. 1995. Bull. Am. Astr. Soc. 29(2), 849.

Modification Date: 28-Aug-18
Author: Dr. R. Marc Kippen
Responsible Manager: Dr. Thomas A. Parnell
Web Curator: Dr. Jerome J. Brainerd