GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"12090 results found.
- ROTSE-IIIa Observations of GRB 041006
- GRB 041006: Optical decay
- Konus-Wind observation of a series SGR 1806-20 bursts on 041005
- Bursts from SGR 1806-20: Preliminary INTEGRAL results
- Very strong outburst from SGR 1806-20 detected with INTEGRAL
- SGR 1806-20 still active
- Konus-Wind and Helicon-Coronas-F observations of GRB040924
- GRB040924,optical observation
- GRB040924, RTT150 optical observation
- GRB040924 : Optical candidate observations at Lulin observatory
- GRB 040924: RTT150 optical observations
- GRB040912(=H3557): Chandra Candidate X-ray Afterglow
- XRF040916: continuing decay of OT
- GRB040912(=H3557): Candidate Optical Afterglow
- GRB040916 optical limits 17 min after GRB
- XRF 040912, identification of CXO sources
- GRB040912(=H3557): Observations with the Chandra X-ray Observatory
- ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
- GRB 040912: Optical Observations
- An intense burst from SGR1806-20
- GRB040912 : Kiso Optical follow-up observation
- HETE 3557: Optical observations
- GRB040912 (= H3557): A Long GRB or XRF Localized by HETE
- GRB040903 - A XRF?
- GRB040827: analysis of the XMM-Newton observation
- Very bright burst detected from SGR 1806-20
- Possible GRB 040903 - further analysis
- GRB 040827 : peak flux
- Increase of SGR 1806-20 activity
- GRB 040812: Optical counterparts of CXO sources
- Bursting activity from SGR 1806-20 detected with IBAS
- Konus-Wind observation of GRB040810 (=H3489)
- GRB 040812: a long GRB detected by INTEGRAL
- GRB 040730: Optical observations
- GRB 040730: a long GRB detected with INTEGRAL
- Ongoing activity of SGR 1806-20
- XRF 040701 - optical observations of the decaying Chandra source
- XRF040701: Second-Epoch Chandra Observations
- Cancellation of IBAS/INTEGRAL GRB alerts
- XRF040701: VLA Observations
- XRF040701: First-Epoch Chandra Observations
- GRB040709 J,H-band observations
- GRB040706:observation at University of Miyazaki
- GRB 040624: optical observations
- GRB 040624: R-band observations
- GRB 040624 - A long GRB detected with INTEGRAL
- IPN Summary of SGR1806-20 Activity in 2004
- SGR 1806-20: no IR variability of the proposed counterparts
- MASTER:HETE Alert 3259 (SRG1806-20) optical observation
- SGR 1806-20, potential NIR counterpart
- MASTER: HETE Alert 3274 optical observation
- Activivty of SGR 1806-20
- IPN triangulation of an intense intermediate burst from SGR1806-20
- IBAS GRB Alerts n.1785 to 1791
- GRB 040511: ROTSE-III Rapid Optical Upper Limits
- GRB 040511: Second Epoch Optical Observations
- GRB 040511: Optical Observations
- GRB040511: Optical Observations
- GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
- IPN triangulation of GRB040425 (=H3183)
- GRB 040422: ROTSE-IIIb Prompt Optical Limits
- GRB 040422: a long GRB detected with INTEGRAL
- GRB 040403, deep optical observations
- HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
- GRB 040403: Optical observations
- GRB 040403: a long GRB detected with INTEGRAL
- Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
- GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
- IBAS GRB Alert 1694
- GRB040323: NIR Observations and Variable Object
- GRB 040323: a long GRB detected with INTEGRAL
- IBAS GRB alerts 1679, 1680, 1681
- GRB040223: Deep NIR NTT data re-analysis
- GRB 031203: spectoscopic evidence for a 1998bw-like SN
- MASTER: RXTE GRB040308 optical observation
- IBAS results on a burst from SGR1806-20
- INTEGRAL detection of activity from SGR1806-20
- IPN triangulation of GRB040228 (H3066, H3067)
- GRB 040223: further offline analysis
- GRB031220: 2nd Chandra observation and X-ray afterglow candidate
- GRB040106, likely optical afterglow
- GRB031220: observation at Univercity of Miyazaki
- GRB 040106 : peak flux
- IPN triangulation of an intermediate burst from SGR1806-20
- GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
- GRB031220(=H2976): Observation with the Chandra X-ray Observatory
- GRB031220: Palomar Observations
- GRB 031220: Subaru observation
- GRB 031220: Optical observation at Tokyo Tech
- GRB031220: ROTSE-IIIb Optical Limits
- GRB031220 : Optical Observation of Lulin Observatory
- GRB 2974 follow-up observations
- GRB 021203: A Normal GRB viewed far off axis?
- GRB 031203: Variable Radio Source
- GRB 031203: Optical/IR Astrometry
- GRB 031203: Deep NIR NTT & VLT observations
- GRB 031203: Radio detection
- IPN triangulation of GRB031127A and B (quasi-simultaneous; large error boxes)
- GRB 031203: further analysis of INTEGRAL data
- GRB 031203: A long GRB detected with INTEGRAL