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 200803A: AstroSat CZTI detection
- GRB 200803A: Fermi GBM detection
- GRB 200803A: Swift-XRT afterglow detection
- Fermi GRB 200803B: Global MASTER-Net observations report
- GRB 200803A: Fermi-LAT detection
- GRB 200803A: MASTER optical counterpart discovery
- GRB 200803B: Fermi GBM Final Real-time Localization
- GRB 200803A: Tiled Swift observations
- LAT GRB200803.15: Global MASTER-Net observations report
- Fermi GRB 200803A: Global MASTER-Net observations report
- GRB 200801B: AstroSat CZTI detection
- GRB 200803A: Fermi GBM Final Real-time Localization
- Fermi GRB 200801B: Global MASTER-Net observations report
- Fermi GRB 200802A: Global MASTER-Net observations report
- AX J1846.4-0258: Swift-BAT refined analysis
- Konus-Wind detection of GRB 200729A
- GRB 200802A: BALROG localization (Fermi Trigger 618061611 / GRB 200802491)
- GRB 200802A: Fermi GBM Final Real-time Localization
- GRB 200801C: BOOTES-1 and BOOTES-2 optical limits
- Fermi GRB 200801A: Global MASTER-Net observations report
- Swift Detection of an SGR-like flare from AX J1846.4-0258
- Swift GRB200801.84: Global MASTER-Net observations report
- GRB 200801B: BALROG localization (Fermi Trigger 617988951 / GRB 200801650)
- GRB 200801B: Fermi GBM Final Real-time Localization
- GRB 200801A: Fermi GBM Final Real-time Localization
- GRB 200729A: RT-22 observations at 36.8 GHz
- GRB 200729A: VLA Observations
- GRB 200729A: Nanshan/NEXT optical upper limit
- GRB 200729A: Swift-BAT refined analysis
- GRB 200729A: further analysis of the NOT data
- GRB 200729A: Swift/UVOT Upper Limits
- GRB 200729A: Swift-XRT refined Analysis
- GRB 200729A: HST imaging
- Fermi-GBM Sub-Threshold candidate for GRB 200729A
- GRB 200729A: IceCube neutrino search
- GRB 200729A: Pan-STARRS pre-explosion source detection
- GRB 200729A: Spitzer archival source detection
- GRB 200729A: TNG NIR upper limits
- GRB 200729A: NOT optical upper limits
- GRB 200729A: Enhanced Swift-XRT position
- GRB200729A: BOOTES-1 optical upper limit
- Swift GRB 200729A: Global MASTER-Net observations report
- GRB 200729A: Swift detection of a burst
- IceCube Alert 200728.35: Global MASTER-Net observations report
- IceCube GCN Notice 134327_10548129 retraction
- Baksan Neutrino Observatory Alert 200726.66: Global MASTER-Net observations report
- GRB 200723A: ATLAS observations of GOTO candidate AT2020qer
- GRB 200723A: Swift ToO observations
- GRB 200723A: GOTO candidate afterglow and host galaxy
- GRB 200724A: Fermi GBM Final Real-time Localization
- Fermi GRB 200723A: Global MASTER-Net observations report
- GRB 200723A: BALROG localization (Fermi Trigger 617214929 / GRB 200723691)
- GRB 200723A: Fermi GBM Final Real-time Localization
- GRB 200716C: Kitab optical observations
- GRB 200722A: BALROG localization (Fermi Trigger 617076900 / GRB 200722094)
- GRB 200716C: CAHA optical observation // Anomalous light curve behavior?
- GRB 200716C: CrAO, Terskol, Assy-Turgen optical observations
- GRB 200714E: Swift-XRT afterglow detection
- GRB 200716C: FRAM-ORM afterglow detection
- Konus-Wind observation of GRB 200716C: correction to GCN 28147
- Konus-Wind observation of GRB 200716C
- GRB 200716C: VIRT optical detection.
- GRB 200716C: Insight-HXMT/HE detection
- AMON IC_HAWC 170720: Correction to ANTARES GCN 28142
- Fermi GRB 200718A: Global MASTER-Net observations report
- AMON IC_HAWC 170720: No Neutrino Counterpart detected with ANTARES
- Fermi GBM trigger 616776657/200718619 is not a GRB
- GRB 200718A: Fermi GBM Final Real-time Localization
- GRB 200716C: CALET Gamma-Ray Burst Monitor detection
- GRB 200716C: Optical observations from HCT
- GRB 200716B: Insight-HXMT/HE detection
- GRB 200716C: Swift-BAT refined analysis
- GRB 200716C: Fermi GBM detection
- Fermi GRB 200716A: Global MASTER-Net observations report
- GRB 200716C: AGILE/MCAL detection
- GRB 200716C: possible host galaxy from the SDSS
- GRB 200716C: Swift-XRT refined analysis correction
- GRB 200716C: Fermi-LAT detection
- GRB 200716C: Swift-XRT refined Analysis
- GRB 200716C: Enhanced Swift-XRT position
- GRB 200522A: HST NIR counterpart confirmation
- GRB200716C: BOOTES-1 optical afterglow detection
- Swift GRB200716C: Global MASTER-Net OT detection
- GRB 200716C: Swift detection of a burst with an optical counterpart
- GRB 200716C: Fermi GBM Final Real-time Localization
- Swift GRB200716.96: Global MASTER-Net observations report
- IPN triangulation of GRB 200716A
- GRB 200716A: Fermi GBM detection
- Fermi GRB 200716B: Global MASTER-Net observations report
- GRB 200716B: AstroSat CZTI detection
- GRB 200716A: AstroSat CZTI detection
- GRB 200716A: AGILE detection
- GRB 200715A: Swift-XRT afterglow detection
- GRB 200716B: BALROG localization (Fermi Trigger 616577673 / GRB 200716316)
- GRB 200716B: Fermi GBM Final Real-time Localization
- GRB 200716A: BALROG localization (Fermi Trigger 616555602 / GRB 200716060)
- GRB 200715A: Swift ToO observations
- GRB 200715A : A long GRB detected by INTEGRAL
- GRB 200716A: Fermi GBM Final Real-time Localization
- GRB 200714E: Fermi GBM observation