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.
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"995 results found.
- GRB 190306A: Tiled Swift observations
- GRB 190306A: MAXI/GSC detection
- IPN Triangulation of GRB 190305A
- GRB 190305A: Swift-XRT observations
- GRB 190305A: Insight-HXMT/HE detection
- GRB 190305A: MAXI/GSC detection
- Trigger 890732: Swift detection of MAXI J1631-479
- Trigger 888312: Swift detection of 4U 1901+03
- GRB 190204A: CALET Gamma-Ray Burst Monitor detection
- Konus-Wind observation of GRB 190204A
- GRB 190204A: AstroSat CZTI detection
- GRB 190204A: MAXI/GSC detection
- GRB 190202A: Swift-XRT refined Analysis
- Fermi GBM trigger 570825115/190202772 is not a GRB
- Fermi GBM trigger 570716645/190201517 is not a GRB
- Fermi GBM trigger 570659556/190131856 is not a GRB
- GRB 190129A: CALET Gamma-Ray Burst Monitor detection
- GRB 190129A: Fermi GBM detection
- GRB 190129A: MAXI/GSC detection
- Trigger 886496: Another Swift trigger on MAXI J1348-630
- Trigger 886486: Swift detection of MAXI J1631-479
- Trigger 886266: Another Swift trigger on MAXI J1348-630
- INTEGRAL triggers from 8205 to 8211 are due to MAXI J1348-630, NOT to a GRB
- Swift Trigger 885960: A third Swift trigger on MAXI J1348-630
- Trigger 885845: A second Swift trigger on MAXI J1348-630
- Trigger 885807: Swift detection of MAXI J1348-630
- Trigger 885456: Swift detection of MAXI J1631-479
- Trigger 884906: Swift detection of MAXI J1631-479
- GRB 190114A: NOEMA detection of the mm afterglow
- Trigger 882561: Swift detection of MAXI J1631-479
- GRB 181222A: AstroSat CZTI detection
- Konus-Wind observation of GRB 181222A
- GRB 181222A: CALET Gamma-Ray Burst Monitor detection
- GRB 181222A: Fermi GBM observation
- GRB 181222A: MAXI/GSC detection
- Konus-Wind observation of GRB 181201A
- GRB 181030A: Swift/UVOT Detection
- GRB 181011A: MITSuME Akeno and Okayama optical upper limits
- GRB 181011A: Global MASTER Net optical inspection
- GRB 181011A: CALET Gamma-Ray Burst Monitor detection
- IPN Triangulation of GRB 181011A (long)
- GRB 181011A: MAXI/GSC detection
- Konus-Wind observation of GRB 180923A
- GRB 180923B - GBM Correction to GCN 23263
- GRB 180923A: CALET Gamma-Ray Burst Monitor detection
- GRB 180923A: MASTER inspection MAXI/GSC error box
- GRB 180923A: MAXI/GSC detection
- GRB 180905A: Swift-XRT refined Analysis
- GRB 180829A: Swift-XRT observations
- GRB 180829A: Tiled Swift observations
- GRB 180829A/MAXI J0406-019: MAXI/GSC detection
- GRB 180809A: further Swift/XRT observations
- GRB 180809A: Fermi GBM observation
- GRB 180809A: CALET Gamma-Ray Burst Monitor detection
- GRB180809B: MASTER Triple Independent Automatic OT Detection
- GRB 180809A: Swift-XRT afterglow detection
- GRB 180809A: Tiled Swift observations
- GRB 180809A: MAXI/GSC detection
- GRB 180701A/MAXI J2119-045: CALET Gamma-Ray Burst Monitor data search
- GRB 180720B: CALET Gamma-Ray Burst Monitor detection
- GRB 180722A: Swift-XRT observations
- GRB 180722A: MASTER second inspection
- GRB 180720B: MASTER Global Net OT observations
- GRB 180720B: ISON-Castelgrande optical observations
- GRB 180722A: Tiled Swift observations
- GRB 180722A: MASTER optical observation
- GRB 180722A: MAXI/GSC detection
- GRB 180720B: MAXI/GSC detection
- Konus-Wind observation of GRB 180701A
- GRB 180701A: MAXI/GSC detection
- Swift trigger 831888: misidentification of 4U 1416-62
- Fermi GBM triggers 544628550/180405571, 544542853/180404579, 544531428/180404447 are not GRBs
- Fermi GBM triggers 544440014/180403389 and 544451446/180403521 are not GRBs
- GRB 180402A, Swift-BAT refined analysis
- GRB 180402A: Swift detection of a possibly short burst
- Swift Trigger 819301: possible GRB 180329A
- Konus-Wind observation of GRB 180326A
- IBAS Alert n. 8033: Not a GRB
- IBAS Alert n. 8032: Not a GRB
- Swift Trigger on MAXI J1820+070
- Trigger 814090: Swift detection of MAXI J1820+070
- MAXI J1820+070: Swift/UVOT counterpart correction
- Swift detection of MAXI J1820+070
- MAXI J1813-095 source: AbAO optical observations
- Swift Trigger 811167: Detection of MAXI J1813-095
- Konus-Wind observation of GRB 180210A
- GRB 180116A: Fermi GBM Detection
- GRB 180116A: MAXI/GSC detection
- GRB 171112A: Fermi GBM Detection
- Konus-Wind observation of GRB 171112A
- GRB 171112A: MAXI/GSC detection
- Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
- Swift Trigger 775946 is a Galactic transient, not GRB 171003
- GRB 170911A: Fermi GBM observation
- GRB 170911A: MAXI/GSC detection
- IBAS Alert nr. 7913 is not a real GRB
- Swift Triggered on MAXI J1535-571
- Swift Trigger on continued activity of MAXI J1535-571
- Swift Triggers on MAXI J1535-571
- Swift Trigger 770431 (GRB 170902A) is a not a GRB