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.
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"20502 results found.
- EP260623a: SVOM/VT optical observations
- EP260623a: TRT optical observations
- EP260623a: REM optical/NIR afterglow detection
- EP 260623a: COLIBRÍ optical observations
- EP260623a: Las Cumbres discovery of the optical counterpart
- EP260623a: Einstein Probe detection of an X-ray transient
- GRB 260614B: EP-FXT follow-up observation
- GRB 260618C: SVOM/ECLAIRs detection of a possible burst through on-ground search
- EP260618a: Liverpool Telescope optical observations
- GRB 260618B: LCO optical observations
- EP260618a: JinShan optical observations
- GRB 260616B/EP260616a: SVOM/GRM detection of a burst
- IceCube-Cascade 260618A: Upper limits from a search for additional neutrino events in IceCube
- GRB 260619A: TRT optical counterpart confirmation
- GRB 260610B: Further GRANDMA Optical Observations and re-brightening detection
- GRB 260610B: VLT/FORS2 spectroscopic observation suggests the non-thermal nature of the optical rebrightening
- Fermi-LAT Gamma-ray Observations of IceCube-260610A
- GRB 260619A: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
- Konus-Wind detection of GRB 260617A
- GRB 260616A: AstroSat CZTI detection
- GRB 260616A: SVOM/GRM observation
- EP260618a: OHP/T193 optical observations
- GRB 260610B/AT2026owq: 1.3m DFOT optical rebrightening detection
- GRB 260619A: Kilonova-Catcher optical upper limit
- EP260618a: LCO optical counterpart confirmation
- EP260618a: COLIBRÍ optical counterpart candidate
- IceCube-260610A: Upper limits from a search for additional neutrino events in IceCube
- EP260618a: EP-WXT detection of an X-ray transient
- GRB 260610B: AbAO optical observations
- GRB 260616C: GECAM-B observation of a burst
- Konus-Wind detection of GRB 260616A
- EP260616a/GRB260616B: COLIBRÍ optical upper limit
- GRB 260610B / AT2026owq: SAO RAS optical observations of possible re-brightening
- GRB 260610B / AT 2026owq: COLIBRÍ further observations and confirmation of the rebrigthening
- EP260616a: EP-WXT detection of a fast X-ray transient
- GRB 260614B: SVOM/ECLAIRs refined analysis
- GRB 260610B: Terskol optical observations
- GRB 260610B: SVOM/GRM observation
- GRB 260614B: SVOM/VT optical candidate from VHF data
- GRB 260614B: SVOM detection of a burst
- GRB 260611B: SVOM/GRM detection
- GRB 260603C: AstroSat CZTI detection
- GRB 260610B: further Liverpool Telescope optical observations
- GRB 260610B / AT2026owq: GRANDMA optical observations
- GRB 260610B / AT2026owq: further SAO RAS optical observations
- EP260605a: COLIBRÍ optical upper limits
- GRB 260610b: Liverpool Telescope optical observations
- EP260610b: Liverpool Telescope optical upper limits
- The EP-WXT trigger 01709269176: SVOM/C-GFT confirmation of a stellar flare
- GRB 260610B / AT2026owq: SAO RAS optical observations
- GRB 260610B: optical counterpart shows spectroscopic redshift of z=0.473
- EP260610b: refined analysis of the EP-WXT and follow-up EP-FXT observations
- GRB 260610B / AT 2026owq: COLIBRÍ optical observations
- GRB 260610B / AT2026owq: Early ATLAS observations
- GRB 260610B: TRT optical observation
- EP260610a: refined analysis of the EP-WXT and follow-up EP-FXT observations
- EP260610b: COLIBRÍ optical observations
- GRB 260610B: DDOTI optical observations
- EP260610b: MAO/AZT-22 optical observations
- EP260610b: NOT optical observation
- EP260610b: SVOM/VT optical confirmation with blue color
- GRB 260515A: SOAR optical observations
- EP260610a: SVOM/VT optical upper limits
- EP260610b: Einstein Probe detection of an X-ray transient
- EP260610a: COLIBRÍ optical upper limits
- EP260610a: Einstein Probe detection of a fast X-ray transient
- Konus-Wind detection of GRB 260604C
- GRB 260604C: AstroSat CZTI detection
- GRB 260604C: SVOM/ECLAIRs refined analysis
- GRB 260608A: SVOM/ECLAIRs refined analysis
- Konus-Wind detection of GRB 260607B
- GRB 260604C: further SAO RAS optical observations
- GRB 260607A / GOTO26fqf / AT2026ong: COLIBRÍ optical observations
- GRB 260604C: SVOM/COLIBRÍ (FM-GFT) colour evolution and confirmation of the late rebrightening
- GRB 260604C: SVOM/C-GFT upper limit
- GRB 260607B: AstroSat CZTI detection
- EP260605a: EP-FXT follow-up observation
- GRB 260607A: TRT optical observations
- GRB 260604A: SVOM/GRM detection
- GRB 260604C: Mondy optical observations: evidence of a possible brightening
- GRB 260604C: Simeiz Zeiss-1000 optical observations of the afterglow
- GRB 260604C: OPD1.6m - GRANDMA observations - detection
- GRB 260604C: 6 GHz VLA observations
- GRB 260604C: SAO RAS optical observations
- GRB 260604B: SVOM/GRM detection
- GRB260603A: SVOM/ECLAIRs refined analysis
- EP260605a: Einstein Probe detection of a fast X-ray transient
- EP260603a: COLIBRÍ optical upper limit
- GRB 260604C: LCO optical upper limit
- EP260602d: EP-FXT follow-up observation
- EP260602c: EP-FXT follow-up observation
- GRB 260601B / EP260601a: AstroSat CZTI detection
- GRB 260527A/EP260527a: 6 GHz VLA observations
- GRB 260604C: Kilonova-Catcher optical afterglow detection
- GRB 260604C: SVOM/COLIBRÍ (FM-GFT) optical observations
- GRB 260604C: Jinshan optical observations
- EP260602d: J-band upper limit with WINTER
- EP260602b: J-band upper limit with WINTER
- GRB 260604C: LAST detection of optical counterpart candidate
- GRB 260604C: SVOM detection of a long burst