GCN Circulars
GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"- GRB 120821A: a long GRB detected by INTEGRAL
- GRB 120817B - PTF Observations
- GRB 120817A: RAPTOR Limits During Gamma-Ray Emitting Interval
- GRB 120811C: optical observations
- GRB 120817B: BAT location in ground analysis and refined analysis
- GRB 120819A: MASTER final limits
- GRB 120819A: Bassano Bresciano Observatory optical observations
- GRB 120819A: Swift-BAT refined analysis
- GRB 120819A: GROND afterglow confirmation
- GRB 120819A: Swift-XRT refined Analysis
- GRB 120819A: MITSuME Ishigakijima upper limits
- GRB 120819A: MITSuME Okayama Optical upper limits
- GRB 120819A: Enhanced Swift-XRT position
- GRB 120819A: afterglow candidate from NOT
- GRB 120819A: MASTER optical observations
- GRB 120819A: Swift detection of a burst
- GRB 120817B: Swift-XRT observations
- GRB 120811C: optical observations
- GRB 120816A: Swift/UVOT Detection of the Optical Afterglow
- GRB 120815A: MASTER-ICATE observations
- Konus-Wind observation of GRB 120816B
- IPN Triangulation of GRB 120816B (short/exceptionally intense)
- Konus-Wind observation of GRB 120817B
- GRB 120817A: Swift-XRT refined Analysis
- GRB 120817B: LCO Optical Observations
- GRB 120817B: Fermi GBM detection
- IPN Triangulation of GRB 120817B (short/very intense)
- GRB 120817A: Swift-BAT refined analysis
- GRB 120816A: optical upper limit
- GRB 120817A: Enhanced Swift-XRT position
- GRB 120815A: Swift/UVOT Detection of the Optical Afterglow
- GRB 120816A: Bassano Bresciano Observatory optical observations
- GRB 120817A: FTN and FTS observations
- GRB 120816A: Swift-XRT refined Analysis
- GRB 120817A: Swift-XRT observations
- GRB 120817A: Swift detection of a burst
- GRB 120816A: Enhanced Swift-XRT position
- GRB 120816A: Swift-BAT refined analysis
- GRB 120816A: BOOTES-2 observations
- GRB120816A: OPTIMA discovery of optical counterpart
- GRB 120816A: TAROT Calern observatory optical observations
- GRB 120816A: ROTSE-III Optical Limits
- GRB 120816A: Swift detection of a burst
- GRB 120815A: Swift-XRT refined Analysis
- GRB 120815A: Swift-BAT refined analysis
- GRB 120805A: Liverpool Telescope optical candidate detection
- GRB 120815A: Enhanced Swift-XRT position
- GRB 120815A: VLT/X-shooter redshift
- GRB 120815A: GROND afterglow candidate
- GRB 120815A: Swift-XRT observations
- GRB 120815A: TAROT La Silla observatory optical observations
- GRB 120815A: Swift detection of a burst
- GRB 120811B: Fermi GBM observation
- GRB 120804A: Possible temporal break in the X-ray light-curve
- GCN for GRB 120811C
- GRB 120811A: Swift/XRT-UVOT Obseravations
- GRB120804A: Chandra observations and afterglow detection
- GRB 120805A: optical afterglow confirmation from the NOT
- GRB 120805A: Enhanced Swift-XRT position
- GRB 120811C: EVLA Observations
- GRB 120811C: RTT150 optical observations
- GRB 120811C: MASTER-Tunka OT observations
- GRB 120811C: Swift-BAT refined analysis
- GRB 120811A: Swift-BAT refined analysis
- GRB 120811C: NOT redshift
- GRB 120811C: Bassano Bresciano Observatory optical observations
- GRB 120811C: Swift-XRT refined Analysis
- GRB 120811C: Swift/UVOT Detection
- GRB 120811C: Redshift from OSIRIS/GTC
- Improved IPN error box for short hard GRB 120811B
- GRB 120811C: RTT150 optical observations
- GRB 120811C: Enhanced Swift-XRT position
- GRB 120811C: TAROT Calern observatory optical observations
- GRB 120811C: MASTER-Amur observations of fading OT
- GRB 120811C: Swift detection of a burst with an optical counterpart
- Konus-Wind observation of GRB 120811B
- IPN Triangulation of short hard GRB 120811B
- Trigger 530588: Swift detection of XMM J174457-2850.3
- Swift Trigger 530581: GRB 120811A or a galactic transient
- GRB 120803A: optical upper limit
- GRB 120807A: Swift/UVOT Upper Limits
- GRB 120803A: Confirmation of the X-ray afterglow
- GRB 120804A: Konus-Wind and Swift/BAT joint spectral analysis
- GRB 120714B: GROND/FORS2 detection of a supernova
- Swift Trigger 530441 is a false trigger
- GRB 120804A: ATCA 34GHz upper limit
- GRB 120807A: Swift-XRT refined Analysis
- GRB 120802A: optical observations
- GRB 120807A: Fermi/LAT upper limit
- GRB 120807A: RAPTOR Limits During Gamma-Ray Emitting Interval
- GRB 120804A: Gemini-North detection of an optical afterglow and putative host galaxy
- GRB 120807A: TAROT La Silla observatory optical observations
- GRB 120807A: Swift-BAT refined analysis
- GRB 120807A: Enhanced Swift-XRT position
- GRB 120807A: Swift detection of a burst
- GRB 120804A: ATCA 34GHz upper limit
- Fermi/GBM detection of an SGR-like burst
- Swift-BAT trigger 530214 is noise
- GRB 120805A: Swift/UVOT Upper Limits
- Swift trigger 530214: uncertain if real or not