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"14834 results found.
- GRB 231222B: Swift-XRT afterglow detection
- GRB 231222B: Fermi GBM Detection
- GRB 231222B: Fermi-LAT detection
- IceCube-231211A: GRANDMA observations of PKS2047+098
- GRID detection of GRB 231215A
- GRB 231222A: Fermi GBM Final Real-time Localization
- GRB 231220A: Fermi GBM Final Real-time Localization
- GRB 231219A: Fermi GBM Final Real-time Localization
- GRID detection of GRB 231205B
- GRID detection of GRB 231205A
- GRB 231216A: 10.4 m GTC optical upper limit
- GRB 231215A: AMI-LA radio detection
- GRB 231216A: AST3-3 YaoAn Optical Upper Limit
- GRB 231216A: BOOTES-2/TELMA optical upper limit
- GRB 231215A: GRBAlpha detection
- GRB 231216A: Swift detection of a burst
- Konus-Wind detection of GRB 231215A
- GRB 231215A: optical afterglow detection from the INAF Asiago Observatory
- GRB 231205B: VZLUSAT-2 detection
- GRB 231204A: VZLUSAT-2 detection
- GRB 231215A: CALET Gamma-Ray Burst Monitor detection
- GRB 231215A : OHP/T193 optical afterglow detection
- GRB 231215A: Swift/UVOT Detection
- GRB 231215A: BOOTES-4/MET optical detection
- GRB 231215A: AGILE detection
- Konus-Wind detection of GRB 231210B
- GRB 231215A: AstroSat CZTI detection
- GRB 231215A : MITSuME Akeno optical afterglow candidate detection
- GRB 231215A: Mondy optical bright afterglow detection
- GRB 231214A: AstroSat CZTI detection
- GRB 231215C: MASTER OT detection
- GRB 231215B: Fermi GBM Final Real-time Localization
- GRB 231215A: Swift detection of a burst
- GRB 231214A: Fermi-LAT detection
- GRB 231214B: Swift/BAT-GUANO detection of a burst
- GRB231214A: BOOTES-6/DPRT optical upper limit
- GRB 231214A: Swift detection of a burst
- GRB 231214A: Fermi GBM Final Real-time Localization
- Fermi-LAT detection of increased gamma-ray activity of blazar PKS 2047+098, located inside the IceCube-231211A error region
- IceCube-231211A - IceCube observation of a high-energy neutrino candidate track-like event
- GRB 231212A: GECAM-C detection of a likely short burst
- GRB 231210B: MeerLICHT afterglow observations
- GRB 231210B: VLT/X-shooter redshift
- GRB 231210B: detection of the optical counterpart with the LCOGT 40cm telescope at Sutherland Observatory
- GRB 231210B: Swift detection of a burst with optical counterpart
- Swift GRB231210.90: Global MASTER-Net OT detection
- IPN triangulation of GRB 231129C
- GRB 231210A: Fermi GBM Final Real-time Localization
- GRB 231208A: GRBAlpha detection
- GRB 231208A: Glowbug gamma-ray detection
- GRB 231208A: AstroSat CZTI detection of a faint burst
- IPN triangulation of GRB 231205A
- GRB 231205B: 1.3m DFOT Optical upper limit
- GRB 231205B: AGILE detection
- GRB 231206B: Fermi GBM Final Real-time Localization
- GRB 231205B: Ondrejov D50 optical upper limit
- GRB 231129C: ASIM MXGS observation and localization
- GRB 231206A: GECAM-B detection of a short burst (correction)
- GRB 231206A: GECAM-B detection of a short burst
- GRB 231205B: GECAM-B detection of a long burst
- GRB 231204A: Glowbug gamma-ray detection
- GRB 231204A: CALET Gamma-Ray Burst Monitor detection
- Fermi-LAT daily aperture light curve of T CrB now available
- GRB 231205B: Swift detection of a burst
- GRB 231204A: AstroSat CZTI detection
- GRB 231205A: GECAM-B detection of a short burst
- GRB 231205A: Fermi GBM Final Real-time Localization
- GRB 231204A: Fermi GBM Final Real-time Localization
- GRB 231203A: Swift/BAT-GUANO detection of a burst outside the coded FOV
- Konus-Wind detection of GRB 231129C
- IceCube-231202A - IceCube observation of a high-energy neutrino candidate track-like event
- The Fermi GBM team reports the detection of a likely SHORT GRB
- GRB 231203A: Fermi GBM Final Real-time Localization
- GRB 231129C: Swift-XRT afterglow detection
- GRB 231129C: PROMPT optical upper limits for the MAXI/GSC X-ray counterpart and the MASTER afterglow candidate
- GRB 231129A: VZLUSAT-2 detection
- GRB 231128A: VZLUSAT-2 detection
- GRB 231129C: AGILE detection
- GRB 231129C: MASTER OT detection
- GRB 231129A: BOOTES-5/JGT optical upper limit
- GRB 231129C: Fermi-LAT detection
- GRB 231129C: GRBAlpha detection
- GRB 231129C: Glowbug gamma-ray detection
- GRB 231129C: GECAM-B detection of a bright burst
- GRB 231129C: AstroSat CZTI detection
- GRB 231129C: CALET Gamma-Ray Burst Monitor detection
- GRB 231127A: GRBAlpha detection
- GRB 231129C: MAXI/GSC detection
- GRB 231129C: Fermi GBM detection of a very bright burst
- GRB 231129C: Fermi GBM Final Real-time Localization
- GRB 231129B: MAXI/GSC detection
- GRB 231129A: GECAM-C detection of a long burst
- GRB 231129A: INTEGRAL detection of a long GRB
- GRB 231129A: Swift detection of a burst
- GRB 231128A: Fermi GBM Final Real-time Localization
- GRB 231117A: MeerKAT 1.3GHz detection
- GRB 231127A: CALET Gamma-Ray Burst Monitor detection
- GRB 231125A: GRBAlpha detection
- GRB 231125A: CALET Gamma-Ray Burst Monitor detection
- GRB 231127A: AstroSat CZTI detection