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"19598 results found.
- GRB 090813, Swift-BAT refined analysis
- Konus-Wind observations of GRB090813
- GRB090813: Swift/UVOT upper limits
- GRB 090813: Enhanced Swift-XRT position
- GRB 090813: Liverpool Telescope afterglow confirmation
- GRB 090813: Swift detection of a burst
- GRB 090812: WIRO NIR upper limit
- GRB 090812: Faulkes Telescope South Continued Optical Monitoring
- GRB 090812: RAPTOR detections during the burst
- GRB 090812: Swift XRT refined analysis
- GRB 090812, RIMOTS optical upper limits
- GRB 090812 Swift-BAT Refined Analysis
- GRB090812: Swift/UVOT observations
- GRB 090812: GROND Observations of the Optical/NIR Afterglow
- GRB 090812: Enhanced Swift-XRT position
- GRB 090812: Liverpool Telescope afterglow confirmation
- GRB 090812: Swift detection of a burst with an optical counterpart
- GRB 090809: Swift-XRT refined analysis
- GRB090809: Swift/UVOT observations
- GRB 090809: Enhanced Swift-XRT position
- GRB 090809: Swift-BAT refined analysis
- GRB 090809: Swift detection of a burst with a possible optical counterpart
- GRB 090807: Liverpool Telescope observations
- GRB 090807: Swift/UVOT Upper Limits
- GRB 090807: Swift-XRT refined analysis
- GRB 090807, Swift-BAT refined analysis
- GRB 090807: Enhanced Swift-XRT position
- GRB 090807, RIMOTS optical upper limits
- GRB 090807: Swift detection of a burst
- GRB 090726: optical observation
- Swift-BAT trigger 358760 is most likely not a GRB
- Swift trigger 358760 is probably a noise event
- GRB 090709A : Quick look analysis of the Suzaku observation
- GRB 090728: Swift-BAT refined analysis
- GRB 090727: GRT Optical Observation
- GRB 090728: Swift XRT refined analysis
- GRB 090726: GRT Optical Observation
- GRB 090727: Swift/UVOT Upper Limits
- GRB 090728: Swift/UVOT Upper Limits
- GRB 090728: Enhanced Swift-XRT position
- GRB 090728, RIMOTS optical upper limits
- GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
- GRB 090728: Swift detection of a burst
- GRB 090727: Swift-BAT refined analysis
- GRB 090727: Swift-XRT refined analysis
- GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
- GRB 090727: Enhanced Swift-XRT position
- GRB 090727: Liverpool Telescope possible OT candidate
- GRB 090727: Swift detection of a burst
- GRB090726: Swift/UVOT observations
- GRB 090726, Swift-BAT refined analysis
- GRB 090726: Afterglow candidate photometryfrom Crni Vrh
- GRB 090726: D50 optical observations
- GRB 090726: Swift-XRT Team refined analysis
- GRB 090726: Enhanced Swift-XRT position
- GRB 090726: Swift/UVOT Finding Chart Observation
- GRB 090726: Swift-XRT position of probable counterpart
- GRB 090726: Swift detection of a burst
- Swift Trigger 358354 is not a GRB
- GRB 090720: Gemini-North Imaging and Optical Afterglow
- Swift XRT and UVOT refned analysis of GRB 090720
- GRB 090709A: Swift XRT Timing Analysis
- GRB 090715B: VLA radio detection
- GRB 090720 Source found in ground processing of Swift-BAT data
- GRB 090715A: Suzaku WAM observation of the prompt emission
- GRB 090709A - CARMA mm Observations
- Konus-Wind observations of short/hard GRB 090715A
- GRB 090715B: MASTER optical limit
- GRB 090715A: Swift-BAT refined analysis
- GRB 090715B: Swift/UVOT followup observations
- GRB 090715B: break in the optical afterglow decay
- GRB 090715B: Enhanced Swift-XRT position
- GRB 090715B: Swift XRT Refined Analysis
- GRB 090715B: Swift-BAT refined analysis
- GRB 090715B - Liverpool Telescope Optical Afterglow Candidate
- Swift problem fixed
- GRB 090715B: Swift detection of a burst with a possible optical counterpart
- GRB 090715A: ROTSE-III Optical Limits
- GRB 090715: Swift detection of a short hard burst
- Swift satellite anomaly
- GRB 090712: Fermi GBM observation
- GRB 090712: Swift-BAT refined analysis
- GRB 090712: Swift detection of a burst
- GRB 090621B: MTM-500 optical observations
- GRB 090709A: deep optical observation with the 10.4m GTC
- GRB 090709A: Suzaku WAM observation of the prompt emission
- GRB 090709A: Swift UVOT upper limits
- GRB 090709B: Fermi GBM detection
- GRB 090709A: confirmation of the periodicity in the SPI-ACS data
- GRB 090709A: evidence for a very red afterglow at low z
- GRB 090709A: RAPTOR Limits During Gamma-Ray Emission
- GRB 090709A: Swift XRT Refined Analysis
- GRB 090709B, Swift-BAT refined analysis
- GRB 090709A: Swift-BAT refined analysis
- GRB090709A: High Energy BAT/XRT Analysis Suggests Low to Moderate Redshift
- GRB 090709A: Wyoming Infrared Observatory NIR upper limits
- GRB 090709A, RIMOTS optical upper limits
- GRB 090709A: Enhanced Swift-XRT position
- GRB 090709B: Swift detection of a burst
- GRB 090708 : Fermi GBM detection