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 220930A: Swift-XRT refined Analysis
- GRB 220930A: LCOGT Optical Upper Limits
- GRB 220930A: Swift/UVOT Upper Limits
- GRB 220930A: Enhanced Swift-XRT position
- Swift GRB 220930A: Global MASTER-Net observations report
- GRB 220930A: BOOTES-5/JGT early optical upper limit
- GRB 220930A: Prompt enhanced Swift-XRT position
- GRB 220930A: COATLI Upper Limits
- GRB 220930A: Swift detection of a burst
- Fermi-LAT gamma-ray observations of IceCube-220928A
- IceCube-220928A: Upper limits from a search for additional neutrino events in IceCube
- Konus-Wind detection of GRB 220927A
- IceCube-220928A - IceCube observation of a high-energy neutrino candidate track-like event
- Fermi GRB 220927A: Global MASTER-Net observations report
- IPN triangulation of GRB 220927A (long)
- GRB 220921A: LCOGT Optical Observations
- GRB 220611A: Host galaxy redshift from VLT/X-shooter
- GRB 220927A: Fermi GBM Final Localization
- GRB 220924A: Fermi GBM detection
- Integral GRB220926.44: Global MASTER-Net observations report
- Ultra-long GRB 220525B: Konus-Wind and Fermi-GBM detection
- Swift Trigger 1125354 (GRB 220926A) is not a GRB
- Swift GRB220926.34: Global MASTER-Net observations report
- Swift GRB 220926A: Global MASTER-Net observations report
- Analysis of long GRB 220926B detected by INTEGRAL
- GRB 220926B
- GRB 220926A: Swift detection of a burst
- Fermi GRB 220925A: Global MASTER-Net observations report
- GRB 220924A: Swift/BAT-GUANO detection outside the coded FOV
- GRB 220921A: further MeerLICHT observations
- GRB 220925A: Fermi GBM Final Real-time Localization
- Fermi trigger No 685748699: Global MASTER-Net observations report
- GRB 220924A: Fermi GBM Final Real-time Localization
- Swift GRB220923.47: Global MASTER-Net observations report
- GRB 220921A: ALMA detection
- GRB 220921A: DDOTI Detection of the Afterglow
- Konus-Wind detection of GRB 220921A
- GRB 220921A: Fermi GBM detection
- IceCube-220907A: Classification of AT2022oyn as a Type Ia supernova
- GRB 220921A: MeerLICHT afterglow observations
- GRB 220921A: Swift-XRT Observations
- GRB 220921A: MASTER OT inside Fermi-LAT error-box
- LAT GRB220921.46: Global MASTER-Net observations report
- GRB 220921A: Fermi-LAT detection
- GRB 220921A: Tiled Swift observations
- Fermi trigger No 685452089: Global MASTER-Net observations report
- Fermi-LAT gamma-ray observations of IceCube-220918A and detection of a new gamma-ray source, Fermi J0502.5+0037
- IceCube-220918A: Upper limits from a search for additional neutrino events in IceCube
- IceCube Alert 220918.53: Global MASTER-Net observations report
- IceCube-220918A - IceCube observation of a high-energy neutrino candidate track-like event
- Fermi trigger No 684894705: Global MASTER-Net observations report
- IceCube-220907A: No significant detection in HAWC
- Improved IPN error box for GRB 220910A
- Fermi trigger No 684927323: Global MASTER-Net observations report
- Fermi trigger No 684911625: Global MASTER-Net observations report
- GRB 220909A: Fermi GBM observation
- Konus-Wind detection of GRB 220910A
- GRB 220910B: Fermi GBM Final Localization
- Fermi trigger No 684716840: Global MASTER-Net observations report
- Fermi GRB 220912A: Global MASTER-Net observations report
- GRB 220910A: Fermi GBM observation
- IPN triangulation of GRB 220910A (bright/long)
- GRB 220912A: AstroSat CZTI detection
- GRB 220831A: DECam optical counterpart follow-up
- GRB 220909A: Swift-XRT observations
- GRB 220912A: Fermi GBM Final Real-time Localization
- IPN triangulation of GRB 220905A
- GRB 220909A: Swift ToO observations
- GRB 220909A: Swift/BAT-GUANO candidate arcminute localization
- GRB 220831A: Gemini-South Infrared Observations
- GRB 220910A: AstroSat CZTI detection
- 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