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"19663 results found.
- GRB 200306C: VIRT optical upper limits
- GRB 200306A: AstroSat CZTI detection
- GRB 200306C: LCO Optical Upper Limits
- GRB 200306C: Liverpool Telescope observations
- GRB 200306C: SAO RAS observations of OT
- GRB 200306C: GOTO upper limits
- GRB 200306A: Swift-XRT refined Analysis
- GRB 200306C: BOOTES-1 detection of the optical afterglow
- Swift GRB200306.95: Global MASTER-Net observations report
- GRB 200306C: Swift detection of a burst with an optical counterpart
- Swift GRB200306.95: Global MASTER-Net OT detection
- Swift GRB200306.95: Global MASTER-Net OT detection
- GRB 200306A: Potential LCO Optical Afterglow Detection
- GRB 200306A: Swift detection of a burst
- Swift GRB200306.01: Global MASTER-Net observations report
- Konus-Wind observation of GRB200303A
- GRB 200303A: Fermi GBM observation
- GRB 200303A: Swift-XRT refined Analysis
- GRB 200303A: Swift-BAT refined analysis
- GRB 200303A: NOT optical observations
- GRB 200303A: Swift/UVOT Upper Limits
- GRB 200303A: FRAM-ORM optical limit
- GRB 200219A: AstroSat CZTI detection
- GRB 200303A: GOTO observations upper limit
- GRB 200228A: AstroSat CZTI detection
- GRB 200303A: CALET Gamma-Ray Burst Monitor detection
- GRB 200303A: Enhanced Swift-XRT position
- GRB 200303A: Swift detection of a burst
- Swift GRB200303.11: Global MASTER-Net observations report
- LIGO/Virgo S200302c: no counterpart candidates in the Swift/BAT observations
- LIGO/Virgo S200224ca: Transient found in Swift/UVOT counterpart search
- GRB 200228B: LCO Optical Upper Limit
- GRB 200228B: Swift-BAT refined analysis
- GRB 200228B: RATIR Optical Observations
- GRB 200228B: Swift-XRT refined Analysis
- Swift GRB 200228B: Global MASTER-Net observations report
- GRB 200228B: Swift/UVOT Upper Limits
- GRB 200228B: RATIR Optical Observations
- GRB 200228B: Fermi GBM observation
- GRB 200227A: RATIR Optical Observations
- GRB 200228B: KAIT Optical Upper Limit
- GRB 200228A: Fermi GBM observation
- GRB 200228A: Swift/BAT detection and arcminute localization from GUANO
- GRB 200227A: Mondy optical upper limit
- GRB 200228B: Enhanced Swift-XRT position
- GRB 200228B: Swift detection of a burst
- GRB 200227A: Insight-HXMT/HE detection
- GRB 200227A: Swift-XRT refined Analysis
- GRB 200227A: Swift-BAT refined analysis
- GRB 200227A: Swift/UVOT Upper Limits
- GRB 200227A: Enhanced Swift-XRT position
- HAWC-200216A: No Neutrino Counterpart in ANTARES Search
- GRB 200227A: Fermi GBM observation
- GRB 200227A: MITSuME Akeno optical upper limit
- GRB 200227A: Swift detection of a burst
- Konus-Wind observation of GRB 200219A
- GRB 200224A: Calar Alto 2.2m optical afterglow detection
- LIGO/Virgo S200225q: no counterpart candidates in the Swift/BAT observations
- LIGO/Virgo S200224ca: no counterpart candidates in the Swift/BAT observations
- GRB 200224A: Swift-BAT refined analysis
- GRB 200224A: LCO Upper Limits
- GRB 200224A: RATIR Optical Observations and Confirmation of the Afterglow
- GRB 200224A: Swift/UVOT Detection
- GRB 200219C: Swift-XRT afterglow confirmation
- GRB 200224A: Swift-XRT refined Analysis
- GRB 200224A: BOOTES-1 and 1.5m OSN optical observations
- GRB 200224A: Swift detection of a burst
- Swift GRB200224.14: Global MASTER-Net observations report
- GRB 200219A: UVOT Upper Limits
- GRB 200219A: FRAM-Auger optical limit
- GRB 200219C: Nanshan/NEXT optical upper limit and possible host galaxy from PanSTARRS
- GRB 200219C: Swift-XRT afterglow detection
- LIGO/Virgo S200213t: Swift UVOT and XRT observations of ZTF20aamvmzj (AT2020cja)
- GRB 200219C: Tiled Swift observations
- GRB 200219C: Fermi-LAT detection
- GRB 200215A: LCO Optical Upper Limits
- GRB 200219A, Swift-BAT refined analysis
- LIGO/Virgo S200219ac: no counterpart candidates in the Swift/BAT observations
- GRB 200219A: Swift-XRT refined Analysis correction
- GRB 200219A: Swift-XRT refined Analysis
- GRB 200219A: Enhanced Swift-XRT position
- GRB 200219A: Fermi GBM observation
- GRB 200216B: second epoch optical upper limit at Mondy observatory
- GRB 200219A: Swift detection of a short burst
- Swift GRB200219.32: Global MASTER-Net observations report
- GRB 200216B: Mondy and AbAO optical upper limits
- LIGO/Virgo (S200213t/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
- GRB 200216B: Swift-XRT refined Analysis
- GRB 200216B: Swift-BAT refined analysis
- Further Swift-XRT observations of Swift J0840.7-3516
- GRB 200215A: CALET Gamma-Ray Burst Monitor detection
- GRB 200216A: Fermi GBM detection
- GRB 200216B: Fermi GBM observation
- GRB 200216B: Swift/UVOT Upper Limits
- GRB 200216A: Swift/BAT detection and arcminute localization from GUANO
- GRB 200216B: Enhanced Swift-XRT position
- GRB 200215A: RATIR Optical Observations
- GRB 200216B: GMG upper limit
- GRB 200216B: Swift detection of a burst
- Swift GRB200216.56: Global MASTER-Net observations report