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"26295 results found.
- GRB 101024A: Swift XRT refined analysis
- GRB 101024A: Zadko observatory - Gingin. Optical observations
- GRB 101023A: miniTAO/ANIR NIR detection
- GRB 101024A: Fermi GBM observation
- GRB 101023A: Fermi GBM observation
- GRB 101024A: Swift-BAT refined analysis
- GRB 101024A: GRAS06 optical observations
- GRB 101024A: Enhanced Swift-XRT position
- Swift/UVOT observations of GRB101023A
- GRB 101024A: Swift detection of a burst with an optical afterglow
- GGRB 101023A: GROND detection of the optical-NIR afterglow
- GRB 101023A: Swift-XRT Team Refined Analysis
- GRB 101023A: Swift-BAT refined analysis
- GRB 101023A: Gemini discovery of optical afterglow
- GRB 101023A: Enhanced Swift-XRT position
- GRB 101023A: Swift detection of a burst
- GRB 101020A, Swift-BAT refined analysis
- GRB 101020A: Swift detection of a burst
- GRB 101017A: Swift/UVOT Observations
- Konus-Wind observation of GRB 101017A
- GRB 101014A: Fermi LAT detection
- GRB 101017A: Enhanced Swift-XRT position
- GRB 101017A: Swift-BAT refined analysis
- GRB 101017A: Swift detection of a burst with optical counterpart
- GRB 101011A: Fermi GBM detection
- Konus-Wind observation of GRB 101014A
- GRB 101014A: Fermi GBM detection
- GRB 100906A: D50 optical detection
- GRB 101011A, GROND upper limits
- GRB 101011A: Zadko observatory - Gingin optical observations
- GRB 101011A: XRT Refined Analysis
- GRB 101011A: Enhanced Swift-XRT position
- GRB 101011A: Swift-BAT refined analysis
- GRB 101011A: Swift detection of a burst
- GRB 101008A: Fermi GBM observation
- GRB 101008A: Swift-BAT refined analysis
- GRB101008A, GROND detection of a fading afterglow
- GRB 101008A: Swift-XRT refined analysis
- GRB 101008A: Enhanced Swift-XRT position
- GRB 101008A: Swift detection of a burst
- Swift Trigger 435520 is probably not a GRB
- GRB 100925A / MAXI J1659-152: MASTER optical observations
- GRB 100924A: Suzaku WAM observation of the prompt emission
- GRB 100928A, Swift-BAT refined analysis
- GRB 100924A: Fermi GBM observation
- GRB 100928A: Swift detection of a burst
- GRB100925A/MAXI J1659-152: Galactic origin from SED analysis
- GRB 100925A/MAXI J1659-152 - NOT optical observations
- GRB 100925A / MAXI J1659-152: BOOTES-2/TELMA and IAC80 optical observations
- MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
- GRB 100925A: Swift detection of a burst
- GRB 100924A: Swift-BAT refined analysis
- GRB 100924A: Swift detection of a burst
- GRB 100917A: TAROT La Silla observatory optical observations
- GRB 100915A: TAROT Calern observatory optical observations
- GRB100906A: Ashra-1 observation of early optical emission
- GRB 100917A: Swift-BAT refined analysis
- GRB 100917A: Swift detection of a burst
- GRB 100915B: GRT Optical Observation
- GRB 100915A: GRT Optical Observation
- GRB 100915B: Fermi GBM observation
- GRB 100915A: Correction to Swift-BAT refined analysis
- GRB 100915A: Swift-BAT refined analysis
- GRB 100915A: Swift-XRT refined analysis
- GRB 100915A: Enhanced Swift-XRT position
- GRB 100915B: a long GRB detected by INTEGRAL
- GRB 100915A: Swift detection of a likely burst
- GRB 100910A: Fermi GBM detection
- Swift BAT Trigger 433953 probably not a GRB
- GRB100909A: NOT optical afterglow confirmation
- GRB 100909A: Swift-XRT refined analysis
- GRB 100901A: optical observation in Maidanak, break confirmation
- GRB 100902A : Confirmation of afterglow and re-brightening with CFHT r’-band imaging
- GRB 100909A: Swift target of opportunity observation
- GRB 100909A: a long GRB detected by INTEGRAL
- EVLA detection of radio afterglow of GRB100901A
- GRB 100901A: CrAO optical observations
- GRB 100906A: GRAS-007 optical observations
- GRB100906A: R band observations
- Konus-Wind observation of GRB 100906A
- GRB 100906A: Fermi GBM observation
- GRB 100906A: Swift-XRT refined analysis
- GRB 100906A: Enhanced Swift-XRT position
- GRB 100906A: Swift/UVOT Observations
- GRB 100901A: TLS observations, SDSS calibration, decay slope
- GRB 100906A: MASTER preliminary prompt+afterglow lc
- GRB 100906A: Swift-BAT refined analysis
- GRB 100906A: MASTER preliminary polarization prompt light curve
- GRB 100906A: Swift detection of a burst with an optical afterglow
- GRB 100905A: Swift-XRT refined analysis.
- GRB 100905A: Enhanced Swift-XRT position
- GRB 100905A: Swift-BAT refined analysis
- GRB 100905A: Swift detection of a burst
- GRB 100904A: Swift-BAT refined analysis
- Konus-Wind observation of GRB 100829A
- GRB 100904A: Swift detection of a burst
- GRB 100902A: Swift-BAT refined analysis
- Tentative redshift of GRB100902A from Swift-XRT data
- GRB 100902A: Swift XRT refined analysis
- GRB 100902A: Enhanced Swift-XRT position