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"22912 results found.
- GRB 101011A: Swift/UVOT observations
- GRB 101011A, GROND upper limits
- GRB 101011A: Zadko observatory - Gingin optical observations
- GRB 101011A: Swift/UVOT Observations of a Possible Optical Afterglow
- GRB 101011A: Enhanced Swift-XRT position
- GRB 101011A: Swift detection of a burst
- GRB101008A, GROND detection of a fading afterglow
- GRB 101008A: Swift-XRT refined analysis
- GRB 101008A: SAO RAS optical observations
- GRB 100915 optical upper limit
- GRB 101008: Swift/UVOT Upper Limits
- GRB 101008A: Enhanced Swift-XRT position
- GRB 101008A: 1.23m CAHA optical observations
- GRB 101008A: Swift/XRT Detection of an Afterglow with no UVOT Counterpart
- GRB 101008A: Swift detection of a burst
- GRB 100728B: X-shooter redshift
- Refined analysis shows Swift Trigger 435520 is not a GRB
- Swift Trigger 435520 is probably not a GRB
- GRB 100928A: Swift detection of a burst
- GRB 100925A / MAXI J1659-152: WSRT Radio and Polarization Detection
- GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation
- GRB 100925A / MAXI J1659-152: SARA-S Observations
- GRB 100925A/MAXI J1659-152: Submm observations from APEX
- GRB100925A/MAXI J1659-152: Galactic origin from SED analysis
- GRB 100925A/MAXI J1659-152 - NOT optical observations
- MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
- GRB 100925A: Nearby DSS Source - SN-GRB or new Galactic transient?
- GRB 100924A: GROND detection of an optical/NIR afterglow
- GRB 100925A: Swift detection of a burst
- 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 100916A: Fermi GBM detection
- GRB 100917A: Swift detection of a burst
- GRB100915A: MITSuME Ishigakijima Optical upper limits
- GRB 100915B: GRT Optical Observation
- GRB 100915A: GRT Optical Observation
- GRB 100915A: Swift/UVOT Upper Limits
- GRB 100915A: Swift-XRT refined analysis
- GRB 100915A: Enhanced Swift-XRT position
- GRB 100915A: Swift detection of a likely burst
- GRB 100910A: Fermi GBM detection
- Swift BAT Trigger 433953 probably not a GRB
- GRB100909A: MITSuME Ishigakijima Optical upper limits
- GRB 100909A: Swift/UVOT observations
- GRB 100901A: errata of GRB name in GCN 11270
- GRB 100909A: Swift-XRT refined analysis
- GRB 100906A: optical observations at Mt.Terskol
- GRB 100901A: optical observation in Maidanak, break confirmation
- GRB 100909A: Faulkes Telescope North afterglow candidate
- GRB 100909A: ROTSE-III Optical Limits
- GRB 100902A : Confirmation of afterglow and re-brightening with CFHT r’-band imaging
- GRB 100909A: Swift target of opportunity observation
- GRB100906A: detection at 15GHz
- GRB100901A: IAO optical upper limits at 4 days after the burst
- GRB 100901A: CrAO optical observations
- GRB100906A: R band observations
- GRB100906A: non-detection at 15GHz
- GRB100906A: Optical observations at IAO
- GRB 100901A: TLS Detection at 5.5 days
- GRB 100906A: Swift-XRT refined analysis
- GRB 100906A: Enhanced Swift-XRT position
- GRB 100906A: Swift/UVOT Observations
- GRB100906A: MITSuME Okayama Optical Observation
- GRB 100906A: TLS Multicolor Observations
- GRB 100905A: Swift/UVOT Upper Limits
- GRB 100906A: Swift detection of a burst with an optical afterglow
- GRB 100829A: MASTER optical observations
- GRB100905A: Optical upper limits at IAO
- GRB100905A: MITSuME Okayama optical upper limits
- GRB 100905A: Swift-XRT refined analysis.
- GRB 100905A: UKIRT zJHK Observation
- GRB 100901A: Possible WSRT Radio Detection
- GRB100905A: 1.5m OSN upper limit
- GRB 100905A: Enhanced Swift-XRT position
- GRB 100905A: Swift-BAT refined analysis
- GRB100904A: BOOTES-3 Upper Limit
- GRB 100905A: Swift detection of a burst
- GRB10901A: Murikabushi telescope observation at 3 days after the burst
- GRB 100901A: Submm observations from SMA
- GRB 100902A: UKIRT JK Observation
- GRB 100904A: Swift-BAT refined analysis
- GRB100902A: Optical upper limits at IAO
- GRB10901A: Optical observations at IAO
- GRB 100904A: Swift detection of a burst
- IPN Triangulation of the very bright GRB 100829A
- GRB 100901A: Lightbuckets Optical Observations
- GRB 100902A: 1.5m OSN I-band Upper Limits
- GRB 100902A: Swift/UVOT Upper Limits
- GRB 100902A: optical observation at Mt.Terskol
- GRB 100901A: optical observation at Mt.Terskol
- GRB100901A: MITSuME Okayama Optical Observation at 1 day after the burst
- GRB 100902A: Enhanced Swift-XRT position
- GRB 100901A: ISON-NM optical observations
- GRB 100902A: Swift detection of a burst
- GRB 100901A: Vega telescope optical afterglow observation
- Swift/UVOT Observations of GRB100901A
- GRB 100901A: SARA-N observations
- GRB100901A: MITSuME Okayama Optical Observation