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.
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"20967 results found.
- GRB 161105A: Swift/UVOT Upper Limits
- GRB 161108A: TAROT Calern observatory optical observations
- GRB 161105A: TAROT La Silla observatory optical observations
- GRB 161108A: NOT redshift
- GRB 161108A: NOT candidate afterglow
- Fermi LAT Gamma-ray Observations of IceCube-161103
- GRB 161022A: 15 GHz upper limits from AMI
- GRB 161017A: 15 GHz upper limits from AMI
- GRB 161104A: Gemini South optical observations
- GRB 161105A: MASTER-IAC early optical observations
- GRB 161104A: GROND observations
- GRB 161104A: Swift/UVOT Upper Limits
- Fermi GBM Observations of IceCube-161103
- IceCube-161103: Swift-XRT observations
- INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161103
- IceCube-161103: MASTER follow-up observations
- GRB 161015A: 15 GHz upper limits from AMI
- GRB 161014A: 15 GHz upper limits from AMI
- GRB 161023A: GROND Observations
- GRB 161023A: Swift-XRT afterglow detection
- GRB 161023A: TAROT La Silla observatory optical observations
- GRB 161023A: Zadko observatory - Gingin optical observations
- GRB 161023A: Watcher optical observations
- GRB 161023A: LCOGT-FTS optical observations
- GRB 161023A: Swift ToO observations
- Radio upper limit on the GRB 161011A with the GMRT
- GRB 161023A VLT/X-shooter redshift
- GRB 161022A: RATIR Optical and NIR Observations
- GRB 161022A: Swift/UVOT Upper Limits
- GRB 161022A: NOT optical observations
- GRB 161022A: LT observations
- GRB 161022A: TAROT Calern observatory optical observations
- GRB 161015A: further Swift-XRT follow-up observations
- GRB 161011A: 15 GHz upper limits from AMI
- GRB 161007A: 15 GHz upper limits from AMI
- GRB161017A: NOEMA detection of the millimetre afterglow
- GRB 161017A: LT optical observations
- GRB161017A optical R band observations with SARA-RM
- GRB 161017A: TNG spectroscopy and redshift confirmation
- GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
- GRB 161017A: Swift/UVOT Detection
- GRB161017A: optical observations with 1-m LCOGT McDonald
- GRB 161017A: TNG optical observations
- GRB 161017A: Redshift from GTC
- GRB 161014A: Continued RATIR Optical and NIR Observations
- GRB 161015A: Swift/UVOT observations
- GRB 161014A: VLT/X-shooter redshift confirmation
- GRB 161014A: refined analysis of TSHAO optical observations
- GRB 161015A: Swift-XRT observations
- GRB 161015A: Tiled Swift observations
- GRB 161014A: RATIR Optical and NIR Observations
- GRB 161014A: TNG optical observations
- GRB 161014A: Continued MITSuME Akeno Optical Observation
- GRB 161014A: Swift/UVOT Detection
- GRB161014A: NOT optical observations
- GRB 161014A: GTC spectroscopy
- GRB 161014A: TSHAO optical observations
- GRB 161011A: RATIR Optical and NIR Observations
- GRB 161014A: Kanata optical observation
- GRB 161010A: Swift/UVOT Possible Detection
- GRB 161011A: Swift burst of interest
- GRB 161011A: Swift/UVOT Upper Limits
- GRB 161010A: Swift-XRT afterglow detection
- GRB 161010A: Swift ToO observations
- GRB 161007A: NOT optical observations
- GRB 161007A: AbAO optical observations
- GRB 161007A: Mondy optical observations
- GRB 161007A: Swift/UVOT Upper Limits
- GRB 161007A: GTC observations
- GRB 161004A: Maidanak optical observations
- GRB 161004A: refined analysis of TSHAO optical observations
- GRB 161007A: MASTER-net early optical observations
- GRB 160821A: Maisoncelles observatory optical observations
- GRB 160927A: GTC observations
- GRB 150302A: late-time imaging and optical afterglow confirmation
- GRB 161001A: IRSF upper limits
- GRB 161004B: Swift/UVOT Upper Limits
- GRB 161004A: RATIR Optical and NIR Observations
- GRB 161004A: Swift/UVOT Detection
- GRB 161004A: Bassano Bresciano Observatory upper limit
- GRB 161004A: TSHAO optical observations
- GRB 160927A: 15 GHz upper limits from AMI
- GRB 161001A: MASTER-OAFA and MASTER-SAAO early optical observations
- GRB 161001A: GROND afterglow candidate
- GRB 161001A: Swift/UVOT Upper Limits
- Possible radio detection of GRB 160910A with the GMRT
- GRB 160927A: Magellan imaging
- GRB 160927A: Swift/UVOT Upper Limits
- GRB 160927A: Bassano Bresciano Observatory optical upper limit
- GRB 160927A: NOT optical observations
- GRB 160927A: GROND Observations
- GRB 160927A: TNG optical afterglow confirmation
- GRB 160917A: 15 GHz upper limits from AMI
- GRB 160912A: 15 GHz upper limits from AMI
- XRT refined analysis for GRB 160925A
- GRB 160925A/MASTER optical transient: Mondy optical observations
- GRB 160925A: MITSuME Akeno Optical Observations
- GRB 160925A: Bassano Bresciano Photometry of MASTER optical transient
- GRB 160925A / Fermi 496473540: MASTER OT observations
- GRB 160925A: Swift ToO observations