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.
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"22215 results found.
- GRB 210610A: Maidanak and AbAO optical observations
- GRB 210905A: REM NIR afterglow detection
- GRB 210905A: VLT/X-shooter spectroscopic redshift
- GRB 210905A: Continued LCO Optical Observations
- GRB 210901A: Swift/UVOT Upper Limits
- Swift GRB 210905A: Global MASTER-Net observations report
- Fermi GRB 210904A: Global MASTER-Net observations report
- Swift GRB210903.59: Global MASTER-Net observations report
- Swift GRB210903.58: Global MASTER-Net observations report
- Swift GRB210903.58: Global MASTER-Net observations report
- Fermi GRB 210903A: Global MASTER-Net observations report
- Fermi GRB 210903B: Global MASTER-Net observations report
- GRB 210901A: GROND observations
- Swift GRB 210901A: Global MASTER-Net observations report
- GRB 210827A: further Swift-XRT observations
- GRB 210827A: Swift/UVOT Upper Limits
- Integral GRB210829.17: Global MASTER-Net observations report
- Integral GRB210829.14: Global MASTER-Net observations report
- Fermi GRB 210827A: Global MASTER-Net observations report
- Fermi GRB 210827B: Global MASTER-Net observations report
- GRB 210827A: Swift-XRT observations
- GRB 210827A: Swift ToO observations
- GRB 210827A: Swift/BAT-GUANO detection and arcminute localization
- GRB 210820A: CAHA 2.2m Optical Detection
- GRB 210824A: Swift/UVOT Upper Limits
- GRB 210826A: Swift/UVOT Upper Limits
- GRB 210826A: Swift-XRT observations
- GRB 210822A: CAHA 2.2m observations
- Fermi GRB 210826A: Global MASTER-Net observations report
- GRB 210826A: Tiled Swift observations
- Swift GRB210825.29: Global MASTER-Net observations report
- GRB 210822A: TSHAO continued optical observation
- GRB 210822A: VLA detection
- GRB 210822A: Swift/UVOT Detection
- Swift GRB 210824A: Global MASTER-Net observations report
- Fermi GRB 210824A: Global MASTER-Net observations report
- GRB 210822A: GROND observations
- GRB 210822A: Detection by GRBAlpha
- GRB 210820A: GROND observations
- Konus-Wind detection of GRB 210822A
- Fermi trigger No 651306769: Global MASTER-Net observations report
- GRB 210820A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
- GRB 210820A: Swift/UVOT Detection
- Fermi GRB 210822B: Global MASTER-Net observations report
- GRB 210822A: Nanshan/NEXT optical observations
- Swift GRB 210822A: Global MASTER-Net observations report
- GRB 210822A: RATIR Optical Detections
- GRB 210822A: KAIT Optical Afterglow Confirmation
- Fermi GRB 210821A: Global MASTER-Net observations report
- GRB 210820A: RATIR Optical Detections
- Swift GRB 210820A: Global MASTER-Net observations report
- Fermi trigger No 651110719: Global MASTER-Net observations report
- Swift GRB210818.68: Global MASTER-Net observations report
- Swift GRB 210818A: Global MASTER-Net observations report
- GRB 210726A: VLA radio afterglow detection
- Konus-Wind detection of GRB 210818A
- IceCube-210730A: not observable by Fermi-GBM
- IceCube-210811A: Upper limits from Fermi-GBM Observations
- Fermi trigger No 650687034: Global MASTER-Net observations report
- GRB 210812A is consistent with being a lensed GRB
- IceCube-210811A: No Candidate Counterparts from the Zwicky Transient Facility
- Fermi GRB 210813A: Global MASTER-Net observations report
- Fermi-LAT Gamma-ray Observations of IceCube-210811A
- GRB 210807A: continued Assy, AbAO and Mondy observations
- Fermi GRB 210812A: Global MASTER-Net observations report
- SGR 1935+2154: SPI INTEGRAL observations on 2021 August 5
- GRB 210730A: Tautenburg observations
- GRB 210807A: Tautenburg observations
- IceCube Alert 210811.09: Global MASTER-Net observations report
- GRB 210807A: Detection by GRBAlpha
- GRB 210802A: Further Swift/XRT observation and afterglow confirmation
- GRB 210807C: Swift/UVOT Upper Limits
- GRB 210807A: Swift/UVOT Detection
- GRB 210807A: correction to the GCN Circ. #30614 Assy optical observations
- GRB 210610B: Assy optical observations
- Swift GRB210807.74: Global MASTER-Net observations report
- Fermi GRB 210807C: Global MASTER-Net observations report
- Swift GRB210807.96: Global MASTER-Net observations report
- Fermi GRB 210807B: Global MASTER-Net observations report
- Swift GRB 210807A: Global MASTER-Net observations report
- Swift GRB210807.79: Global MASTER-Net observations report
- Swift GRB210807.78: Global MASTER-Net observations report
- Fermi trigger No 650046564: Global MASTER-Net observations report
- Fermi trigger No 649814537: Global MASTER-Net observations report
- Fermi trigger No 649684549: Global MASTER-Net observations report
- GRB 210802A: Swift-XRT afterglow detection
- GRB 210802A: Tiled Swift observations
- Fermi trigger No 649627691: Global MASTER-Net observations report
- GRB 210731A: continued GROND observations
- GRB 210731A: VLT/X-shooter redshift
- Fermi trigger No 649524889: Global MASTER-Net observations report
- Fermi trigger No 649519043: Global MASTER-Net observations report
- GRB 210731A: GROND observations
- GRB 210731A: Swift/UVOT Detection of an optical afterglow
- Swift GRB210731.62: Global MASTER-Net observations report
- GRB 210731A: MeerLICHT optical afterglow detection
- Swift GRB210731.93: Global MASTER-Net observations report
- Fermi-LAT Gamma-ray Observations of IceCube-210730A
- GRB 210730A: Campo Imperatore optical observations
- Swift GRB 210730A: Global MASTER-Net observations report