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').
Advanced Search
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"15264 results found.
- GRB040916: Archival optical observations
- GRB040912(=H3557): Observations with the Chandra X-ray Observatory
- GRB040916: Optical observations
- ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
- GRB040912 (= H3557): Chandra Observations Scheduled
- GRB 040912, BVRI observations
- Optical observations of field of GRB040912
- GRB040903 - A XRF?
- ROTSE-III Rapid Response to possible GRB 040903 (INTEGRAL #1972)
- Possible GRB 040903 detected with INTEGRAL
- XMM-Newton Images of GRB 040827
- GRB 040827: K imaging - no evidence of variability
- GRB 040827: Detection of NIR afterglow
- GRB 040827: RTT150 optical observations
- GRB040827 optical observations
- GRB 040827 - Refined position
- GRB040825B (=H3510): An XRF Localized in Real Time by HETE
- GRB040825B: Correction to GCN 2657
- GRB 040812: Second epoch CXO Observations
- GRB040823,optical observation
- XRF040812: GMRT observations
- CXO observation of GRB 040812
- GRB 040810: Optical observations of a limited region
- GRB040624: optical monitoring at TNG
- XRF040701: First-Epoch Chandra Observations
- GRB040706:observation at University of Miyazaki
- XRF040701 (=U11548): a bright XRF detected by HETE
- GRB 040624: optical observations at TNG and VLT
- MASTER: GRB 040624 optical observation after 0,48d
- GRB 040624, optical observations
- GRB 030329: Rebrightening of hyperluminal ejecta.
- SGR 1806-20: no IR variability of the proposed counterparts
- MASTER:HETE Alert 3259 (SRG1806-20) optical observation
- SGR 1806-20, potential NIR counterpart
- GRB 040606: Optical observations
- GRB 040511: NIR observations with REM
- GRB040511: Optical Observations
- GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
- GRB 040423 (=H3175): A Long GRB Localized by HETE
- GRB 040422: ROTSE-IIIb Prompt Optical Limits
- GRB 040422,optical observation
- GRB 040403: Optical observations
- GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
- GRB 031203: spectoscopic evidence for a 1998bw-like SN
- IBAS results on a burst from SGR1806-20
- IPN triangulation of GRB040228 (H3066, H3067)
- GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM
- XMM-Newton Images of GRB 040223
- GRB 040223: REM IJK Observations
- GRB031220: 2nd Chandra observation and X-ray afterglow candidate
- GRB040106: refined X-ray transient position
- GRB040106, Radio Observations
- GRB 040106 : a long GRB detected with INTEGRAL
- GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
- GRB031220(=H2976): Observation with the Chandra X-ray Observatory
- GRB 031203 I-band monitoring
- IPN triangulation of GRB031214 (short/hard; very intense; small error box)
- GRB 2974 follow-up observations
- GRB031203, improved XMM position
- GRB 021203: A Normal GRB viewed far off axis?
- GRB 031203: Variable Radio Source
- GRB 031203: Optical/IR Astrometry
- XMM-Newton Observation of GRB031203
- XMM-Newton Observation of GRB031203
- GRB 031203: Further reports on December 4 observations
- GRB 031203: IR NTTobservations do not confirm REM detection
- GRB 031203: Apparent Spectral Break
- GRB031203: Planned XMM-Newton observation II
- GRB 031203: A long GRB detected with INTEGRAL
- IPN triangulation of GRB031107 (two large error boxes)
- IPN triangulation of GRB031111 (=H2924): small error box
- XRF031109 (=H2919): A very long XRF localized by HETE
- SN 2003jd (SN/GRB?), Radio Observations
- SN 2003jd (SN/GRB?) - possible association with GRB 030929
- GRB 031026 (=H2882): Evidence for High Redshift from Prompt
- Peculiar Type Ic SN 2003jd (SN/GRB?), optical spectrum
- GRB031026 (=H2882): A Long, Hard Spectrum Burst Localized by HETE
- IPN triangulation of GRB031024 (annulus)
- IBAS alert 1180 refers to a burst from SGR 1806-20
- Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
- SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
- A burst from SGR 1806-20 detected with IBAS
- XRF 030824: Early follow-up observation at Kiso observatory
- XRF030824 (=H2821): An X-Ray Flash Localized by the HETE WXM
- XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
- GRB030913: Subaru Optical Observations
- GRB 030913: ROTSE-3c Optical Observations
- GRB030913: OT's limit by MASTER
- GRB030913, candidate afterglow observations
- GRB030913: AAVSO optical observations
- GRB030913 (=H2849): Confirmation of the Flight Localization
- Magellan Observations of GRB030725 (=H2779)
- GRB030913 (=H2849): A GRB Possibly Localized by HETE
- XRF030824: Optical observations
- GRB 030824: Candidate Follow-Up
- XRF030824: Second-epoch Palomar observations
- XRF030824: optical observations
- GRB030823: optical observations
- GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
- 030813 SGR event (Konus-Wind observation)