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.
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"16162 results found.
- GRB 121226A: 5.8 GHz VLA observations
- GRB 121229A: Swift/UVOT Upper Limits
- Skynet/PROMPT observations of GRB121229a
- GRB 121226A: 10.4m GTC optical observations
- GRB 121226A: Swift/UVOT Upper Limits
- GRB 121226A: NOT optical upper limit
- GRB 121226A: Optical Observations
- GRB 121226A: MITSuME Okayama Optical upper limits
- GRB 121226A: Zadko observatory - Gingin optical observations
- GRB 121226A: BOOTES-4/MET optical observations
- GRB 121217A: ATCA 44GHz upper limit
- GRB 121217A: Swift/UVOT Detection
- GRB 121209A: LOAO Observation
- GRB 121209A: Swift/UVOT Upper Limits
- GRB 121212A: PdBI mm observations
- GRB121212A: NOT optical imaging
- GRB 121211A: Continued RATIR Optical and NIR Observations, Fading
- GRB 121212A: Maidanak optical observations
- GRB 121211A: RATIR Optical and NIR Observations
- GRB 121212A: RAPTOR Limits During Gamma-Ray Emitting Interval
- GRB 121211A: RAPTOR Limits During Gamma-Ray Emitting Interval
- GRB 121212A: optical observations in ISON-NM observatory
- GRB 121211A: MITSuME Okayama Optical Observation
- GRB 121211A: Keck/LRIS redshift
- GRB 121211A - Faulkes Telescope North afterglow confirmation
- GRB 121211A: Swift detection of a burst with an optical counterpart
- GRB 121209A: Keck observations
- GRB 121209A: CARMA 3mm Observations
- GRB 121209A: EVLA Observations
- GRB121209A: RATIR Optical and NIR Upper Limits
- GRB 121209A: GROND optical afterglow candidate
- GRB 121209A: Gemini-South imaging
- GRB 121128A: Optical Observations
- GRB 121202A: Swift/UVOT Upper Limits
- GRB 121202A: TAROT Calern observatory optical observations
- GRB 121201A: GROND afterglow observations and photometric redshift
- GRB 121201A: BOOTES-4 optical observations
- GRB 121201A: a GRB with an optical counterpart
- GRB 121128A: optical observation in Mondy observatory
- GRB 121128A: MITSuME Akeno Optical upper limits
- GRB 121125A: optical upper limit
- GRB 121128A: optical observation in Mondy observatory
- GRB 121128A: WSRT radio observation
- GRB 121128A: RAPTOR Detection During Gamma-Ray Emitting Interval
- GRB 121128A, Swift-BAT refined analysis
- GRB 121128A: FTN optical afterglow confirmation
- GRB 121128A: Swift detection of a burst with an optical counterpart
- GRB 121123A: Swift/UVOT Observations
- GRB 121125A: LOAO Observation
- GRB 121125A: MASTER-NET optical observations
- GRB 121125A: Swift detection of a burst with optical counterpart
- GRB 121123A: GROND observations
- GRB 121123A: optical observations
- GRB 121123A: BOOTES-4 and IAC80 optical observations
- GRB 121123A: NOT optical observations
- GRB 121123A: MASTER-NET optical limit
- GRB 121123A: GMG optical observation
- GRB 121123A: Swift detection of a burst with optical counterpart
- GRB 121108A: optical upper limit
- GRB 121117A: Optical observations
- GRB 121117A: optical upper limit
- GRB 121117A: Swift/UVOT Observations
- GRB 121117A: MASTER prompt optical limit
- GRB 121117A: ROTSE-III Optical Limits
- GRB 121117A: BOOTES-3 early optical upper limit
- GRB 121108A: Swift/UVOT Upper Limits
- GRB 121108A: Xinglong TNT upper limit
- GRB 121108A : Lulin/TRIPOL2 Optical Limits
- GRB 121108A: Optical observations
- GRB 121108A: MITSuME Ishigakijima upper limits
- GRB 121108A: Weihai observatory optical observations
- GRB 121108A: MASTER early prompt optical limit
- GRB 121108A: TAROT Calern observatory optical observations
- GRB 121102A: Swift/UVOT Upper Limits
- GRB 121031A: Swift/UVOT Upper Limits
- GRB 121027A: X-shooter redshift confirmation
- GRB 121024A: SMARTS optical/IR afterglow observations
- GRB 121027A: GROND Confirmation of Rebrightening
- GRB 121028A: RAPTOR Limits During Gamma-Ray Emitting Interval
- GRB 121027A: MASTER early prompt optical limit
- GRB 121028A: MITSuME Okayama Optical upper limits
- GRB 121011A: optical observations
- GRB 121024A: optical observations
- GRB 121024A: EVLA Detection
- GRB 121024A: Swift/UVOT Observations
- GRB 121024A: CARMA 3mm Detection
- GRB 121024A: GMG optical observation
- GRB 121024A: MITSuME Ishigakijima upper limits
- GRB 121024A: MITSuME Okayama Optical upper limits
- GRB 121024A: PAIRITEL NIR Detection
- GRB 121024A: GROND Detection of the Optical/NIR Afterglow
- Skynet PROMPT/Dolomiti observations of GRB121024A
- GRB 121024A: BOOTES-1B optical detection
- GRB 121024A: TAROT Calern observatory optical detection of a bright counterpart
- GRB 121024A: Swift detection of a burst with an optical counterpart
- GRB 121011A: early optical light curve
- GRB 121017A: Swift/UVOT Upper Limits
- GRB 121017A: GROND Observations
- GRB 121017A: 1.23m CAHA R-band observations
- GRB 121017A optical observations