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.
Advanced Search Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"- 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
- Swift-BAT trigger 529813 is due to noise while entering the SAA
- GRB 120728A: Fermi GBM observation
- GRB 120805A: Swift-BAT refined analysis
- GRB 120802A: Swift/UVOT Upper Limits
- GRB 120805A: Swift-XRT refined Analysis
- GRB 120805A: 1.23m CAHA observations
- GRB120805A: Liverpool Telescope observations
- GRB 120805A: TAROT Calern observatory optical observations
- GRB 120805A: Swift detection of a burst
- GRB 120804A: EVLA Detection
- GRB 120804A: Gemini-North observations
- GRB 120804A: Swift-BAT Spectral lag analysis
- GRB 120804A: MITSuME Okayama Optical upper limits
- GRB 120803B: Swift-XRT refined Analysis
- GRB 120804A: Swift/UVOT Upper Limits
- GRB 120804A: Swift-BAT refined analysis
- GRB 120804A: Swift-XRT refined Analysis
- GRB 120804A: GROND upper limits
- GRB 120802A: EVLA Observations
- GRB 120804A: Enhanced Swift-XRT position
- Erratum of subject line of GCN13570 (GRB 120803A => GRB 120803B)
- GRB 120803B: MITSuME Okayama Optical upper limits
- GRB 120803A: MITSuME Okayama Optical upper limits
- GRB 120804A: Swift detection of a short burst
- GRB 120803B: Swift-BAT refined analysis
- GRB 120803B: Enhanced Swift-XRT position
- GRB 120803B: MITSuME Akeno Optical upper limits
- GRB 120803A: Swift-XRT Observations
- GRB 120803A: Swift-BAT refined analysis
- GRB 120803B: FTN possible afterglow candidate
- GRB 120803B: Swift detection of a burst
- GRB 120803A: Swift detection of a possible burst
- GRB 120802A: GRT Optical Observation
- GRB 120802A: Swift-XRT refined Analysis
- GRB 120802A Gemini-N redshift
- GRB 120802A: APEX/LABOCA submm observations
- GRB 120729A: Fermi GBM observation
- GRB 120802A: Swift-BAT refined analysis
- GRB 120802A: Enhanced Swift-XRT position
- GRB 120802A: MASTER optical observations
- GRB 120802A: optical uper limit in ISON-NM observatory
- GRB 120802A: Swift detection of a burst
- GRB 120729A: JCMT SCUBA-2 sub-mm observation
- GRB 120728B: Fermi GBM detection
- Konus-Wind observation of GRB 120728B
- GRB 120729A: break in the optical light curve
- GRB 120729A: Optical observations from OSN, BOOTES1/2 and IAC80
- IPN Triangulation of GRB 120728B (long/intense)
- GRB 120729A: RTT150 optical observations
- GRB 120729A: EVLA Observations
- Virtual Telescope observations of GRB 120729A
- GRB 120729A: Early RAPTOR Observations
- GRB 120729A: UKIRT Observation
- T100 observations of GRB 120729A
- GRB 120728A: GROND Afterglow discovery
- GRB 120729A: Swift-XRT refined Analysis
- Correction to Swift GCN Circular 13538
- GRB 120729A: Swift/UVOT Detection
- Swift Trigger 529076 is from Swift J1910.2-0546 and is not a GRB
- GRB 120729A: Xinglong TNT optical upper limit
- GRB 120729A, Swift-BAT refined analysis
- GRB 120728A, Swift-BAT refined analysis
- GRB 120729A: Enhanced Swift-XRT position
- GRB 120728A: Swift/UVOT Upper Limits
- GRB 120729A Gemini-N redshift
- GRB120729A - Faulkes Telescope North Optical Afterglow Candidate
- GRB 120729A: Swift detection of a burst with an optical afterglow