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 220910A: AGILE detection
- GRB 220909A: Fermi GBM Final Real-time Localization
- IceCube-220907A: Upper limits from a search for additional neutrino events in IceCube
- GRB 220907A: Swift-BAT refined analysis
- IceCube-220907A: One Candidate Counterpart from the Zwicky Transient Facility
- GRB 220831A: Gemini-South/GMOS detection of potential optical counterpart
- IPN triangulation of GRB 220903A (long)
- GRB 220907A: Fermi GBM observation
- GRB 220907A: Nanshan/NEXT optical upper limits
- GRB 220907A: Swift/UVOT Upper Limits
- GRB 220907A: Swift-XRT refined Analysis
- GRB 220831A: ATCA 5/9 GHz radio observations
- Fermi-LAT Gamma-ray Observations of IceCube-220907A
- GRB 220907A: Swift-XRT position
- GRB 220907A: Swift detection of a burst
- GRB 220907A: Fermi GBM Final Real-time Localization
- Swift GRB220907.59: Global MASTER-Net observations report
- IceCube-220907A - IceCube observation of a high-energy neutrino candidate track-like event
- IceCube Alert 220907.28: Global MASTER-Net observations report
- GRB 220831A: Swift-UVOT Upper Limits
- Fermi GRB 220905A: Global MASTER-Net observations report
- GRB 220905A: BALROG localization (Fermi Trigger 684070128 / GRB 220905478)
- GRB 220905A: Fermi GBM Final Real-time Localization
- Introducing Self-Service Configuration of GCN Notices over Email for Transient Alerts
- GRB 220831A: DECam detection of a possible optical counterpart
- Fermi GRB 220902A: Global MASTER-Net observations report
- GRB 220902A: Fermi GBM Final Real-time Localization
- GRB 220831A, VLT/HAWK-I near-infrared observations
- GRB 220831C: Fermi GBM Final Localization
- GRB 220831A: Fermi GBM observation
- GRB 220831A: Swift-XRT observations
- GRB 220831B: Fermi GBM Final Localization
- GRB 220831A: Swift ToO observations
- Fermi trigger No 683654200: Global MASTER-Net observations report
- GRB 220831A: Swift/BAT-GUANO localization of a short burst
- Fermi trigger No 683646997: Global MASTER-Net observations report
- IceCube-220822A: No significant detection in HAWC
- Fermi trigger No 683537972: Global MASTER-Net observations report
- Fermi GBM trigger 683571622/220830709 is not a GRB
- Fermi trigger No 683476673: Global MASTER-Net observations report
- Konus-Wind detection of GRB 220826A
- IceCube-Cascade 220826A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220822A: Classification of AT2022saw as a Type Ia supernova
- GRB 220827A: Fermi GBM Final Real-time Localization
- GRB 220826A: Swift-BAT refined analysis
- GRB 220826A: Fermi GBM observation
- Fermi trigger No 683202084: Global MASTER-Net observations report
- Fermi trigger No 683183601: Global MASTER-Net observations report
- Fermi trigger No 683152759: Global MASTER-Net observations report
- GRB 220826A: Swift-XRT refined Analysis
- GRB 220825A: Fermi GBM observation
- GRB 220826A: Lesedi optical afterglow detection
- GRB 220826A: Swift/UVOT Detection
- GRB 220826A: iTelescope optical afterglow observations
- Swift GRB 220826A: Global MASTER-Net observations report
- GRB 220826A: Enhanced Swift-XRT position
- GRB 220826A: Swift detection of a burst with an optical counterpart
- GRB 220825A: Swift/BAT-GUANO detection
- GRB 220825A: Fermi GBM Final Localization
- IceCube-220822A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-220822A: One Candidate Counterpart from the Zwicky Transient Facility
- GRB 220823A: Fermi GBM detection
- Fermi-LAT gamma-ray observations of IceCube-220822A and detection of a new gamma-ray source, Fermi J1810.1+2154
- Fermi trigger No 682918137: Global MASTER-Net observations report
- GRB 220823A: Swift/BAT-GUANO detection of a short burst
- IceCube-220822A - IceCube observation of a high-energy neutrino candidate track-like event
- IceCube Alert 220822.85: Global MASTER-Net observations report
- GRB 220821A: Fermi GBM Final Real-time Localization
- Konus-Wind detection of GRB 220813A
- GRB 220813A: VLT optical observations and possible host galaxy
- GRB 220813A: Swift/UVOT Detection
- GRB 220810A: Further Swift-XRT observations
- GRB 220813A: Swift-XRT refined Analysis
- Swift GRB 220813A: Global MASTER-Net observations report
- GRB 220813A: Enhanced Swift-XRT position
- GRB 220813A: Swift detection of a burst with an optical counterpart
- GRB 220810A: Swift-XRT observations
- GRB 220719B: Detection by VZLUSAT-2
- Fermi trigger No 681998863: Global MASTER-Net observations report
- GRB 220810A: Swift ToO observations
- GRB 220810A: MeerLICHT detection of two afterglow candidates
- Fermi GBM trigger 681998863/220812505 is not a GRB
- Fermi trigger No 681890304: Global MASTER-Net observations report
- Fermi GBM trigger 681890304/220811249 is not a GRB
- Fermi GRB 220810A: Global MASTER-Net observations report
- GRB 220810A: Fermi GBM Final Real-time Localization
- GRB 220627A: MeerKAT radio observations
- GRB 220806A: Swift-BAT refined analysis
- Fermi trigger No 681719116: Global MASTER-Net observations report
- Fermi GBM trigger 681719116/220809267 is not a GRB
- Fermi trigger No 681633544: Global MASTER-Net observations report
- IceCube Astrotrack Bronze 136918_45252263.amon is likely background
- Fermi GBM trigger 681633544/220808277 is not a GRB
- IceCube Alert 220808.33: Global MASTER-Net observations report
- Fermi GBM trigger 681547990 / 220807287 is not a GRB
- GRB 220806A: Swift detection of a burst
- Swift GRB220806.76: Global MASTER-Net observations report
- GRB 220804A: Fermi GBM Final Localization
- Fermi trigger No 681271717: Global MASTER-Net observations report
- GRB 220803A: AstroSat CZTI detection