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"5559 results found.
- GRB 190331A: Insight-HXMT/HE detection
- GRB 190330A: Insight-HXMT/HE detection
- IceCube-190331A - IceCube observation of a high-energy neutrino candidate event
- GRB 190326B: Insight-HXMT/HE detection
- GRB 190326A: Insight-HXMT/HE detection
- GRB 190324A: Swift/UVOT Observations
- GRB 190324B: Insight-HXMT/HE detection
- GRB 190324A: Insight-HXMT/HE detection
- GRB 190323A: Insight-HXMT/HE detection
- GRB190324A: MASTER OT observations
- GRB 190321A: Insight-HXMT/HE detection
- GRB 190324A: Swift/UVOT afterglow candidate
- SWIFT GRB190324.95 Global MASTER-Net observations report
- SWIFT GRB190323.85 Global MASTER-Net observations report
- GRB190320A: MASTER GRB counterpart decay
- GRB190320A: MASTER OT detection
- SWIFT GRB190320.05 Global MASTER-Net observations report
- Fermi trigger 574140965 / GRB190313.15: MASTER Global Robotic Net optical observation
- GRB 190311A: Mondy optical observations
- GRB190305A: MASTER Global Robotic Net optical observation
- GRB190311A: OAO observations
- [Hxmt-ba]GRB 190310A: Insight-HXMT/HE detection
- GRB 190311A: TSHAO optical observations
- GRB190311A: MASTER Global Robotic Net OT optical observation
- GRB 190311A: NEXT-0.6m optical afterglow detection
- GRB 190306B: Insight-HXMT/HE detection
- GRB 190305A: Insight-HXMT/HE detection
- GRB 190305A: MAXI/GSC detection
- Swift Trigger 891843 is not a GRB
- GRB 190305A: AGILE/MCAL detection of a burst
- IceCube-190221A: Fermi-LAT Gamma-ray observations
- GRB 190220A: Swift detection of a burst with an optical counterpart
- Trigger 889483: Swift detection of Swift J1858.6-0814
- GRB 190206A: AstroSat CZTI detection
- Trigger 888312: Swift detection of 4U 1901+03
- Konus-Wind observation of GRB 190206A
- IPN Triangulation of GRB 190206A (short/extremely bright)
- GRB 190203A: Mondy optical observations
- GRB 190202A: Xinglong-2.16m optical observations
- GRB 190204A: MAXI/GSC detection
- Swift Trigger 887541: MASTER optical observation
- GRB 190203A: MASTER OT detection
- GRB 190203A: Koshka Zeiss-1000 optical upper limit
- Improved IPN error box for GRB 190129B
- INTEGRAL observation of IceCube-190124A
- Trigger 885807: Swift detection of MAXI J1348-630
- Search for counterparts to IceCube-190124A with IceCube
- Fermi-LAT Gamma-ray Observations of IceCube-190124A
- IceCube-190124A - IceCube observation of a high-energy neutrino candidate event
- Trigger 885456: Swift detection of MAXI J1631-479
- GRB 190114C: VLA Detection
- GRB 190114C: Swift/UVOT Detection
- GRB 190114C: Fermi-LAT detection
- GRB 190114C: Swift detection of a very bright burst with a bright optical counterpart
- GRB 190114A: GROND detection of the afterglow
- GRB 190114A: VLT/X-shooter redshift
- GRB 190114A: Swift detection of a burst
- GRB 190109B: Mondy optical upper limit
- GRB 190103B: CALET Gamma-Ray Burst Monitor detection
- GRB 190106A: GWAC-F60B optical detection
- Search for Counterparts to IceCube-190104A with IceCube
- Konus-Wind observation of GRB 190103B
- Fermi LAT Gamma-ray Observations of IceCube-190104A
- GRB 190103B: Swift detection of a burst
- GRB 190103A: AGILE/MCAL detection of a burst
- GRB 181231A: Fermi GBM detection
- GRB 181231A: Fermi-LAT detection
- FRB 181228: Global MASTER Net optical inspection
- Swift Trigger 880127 is not a GRB
- GRB 181228A: REM NIR detection
- GRB 181225A: KAIT Follow-Up Observations with Upper Limit
- GRB 181228A: KAIT Optical Upper Limit
- GRB 181222A: MAXI/GSC detection
- GRB 181212A: Fermi GBM Detection
- GRB 181201A: continued optical observations in Mondy
- MASTER: OTs detection during Fermi alert trigger 565936249 early observations
- GRB181201A: GOTO optical observations
- GRB 181201A: continued optical observations in SAAO and Chilesope
- GRB 181201A: Further COATLI Optical Monitoring
- GRB 181202A: Swift detection of a burst with an optical counterpart
- GRB 181201A MASTER-Net OT detection
- GRB 181123B: Swift detection of a short burst
- Fermi GRB 181105.31: Global MASTER Net optical observations
- GRB 181103A: AbAO optical upper limit
- GRB 181103A: Nanshan-1m optical upper limit
- GRB 181030A: MASTER Net OT detection
- GRB 181027A: Swift detection of a burst
- Fermi-LAT Gamma-ray Observations of IceCube-181023A
- GRB 181022A: Swift-XRT refined Analysis
- Baksan Neutrino BNO 181021: Global MASTER-net Optical Follow-up Observations
- GRB 181020A: Global MASTER Net OT observations
- GRB 181016A: Swift detection of a burst
- GRB 181013A: Global MASTER Net optical observations
- 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
- GRB 181008B: Global MASTER Net optical inspection
- GRB 181010A: ePESSTO NTT optical observations
- GRB 181010A: Swift/UVOT Detection