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"19539 results found.
- GRB 100418A: Maidanak optical observations
- GRB 100513A: CrAO optical observations
- GRB 100514A: CrAO optical observations
- GRB 100526A: optical upper limit
- Swift UVOT and UVOT-enhanced XRT position for GRB 100528A
- GRB100526B: GROND Upper limits
- GRB 100526B: Swift-XRT confirmation of fading afterglow
- GRB 100526B: Swift/UVOT Upper Limits
- GRB 100526A: Swift/UVOT Upper Limits
- GRB 100526A: Swift XRT refined analysis
- GRB 100526B: Swift-BAT refined analysis
- GRB 100526B: Swift XRT/UVOT observations
- GRB 100526A: Swift-BAT refined analysis
- GRB 100526A: Enhanced Swift-XRT position
- GRB 100526B: Swift detection of a probable GRB
- GRB 100526A: MASTER-Net optical alert observations
- GRB 100526A: Swift detection of a burst
- Konus-Wind observation of GRB 100522A
- GRB100522A: Suzaku WAM observation of the prompt emission
- GRB 100522A: GROND observations, upper limits
- Swift/UVOT observations of GRB100522A.
- GRB 100522A: Fermi GBM observation
- GRB 100522A: Swift XRT refined analysis
- GRB 100522A, Swift-BAT refined analysis
- GRB 100522A: Enhanced Swift-XRT position
- GRB 100522A: BOOTES-2 optical limit
- GRB 100522A: Swift detection of a burst
- GRB 100418A: CrAO optical observations
- GRB 100518A: Swift/UVOT Upper Limits
- GRB 100518A: Swift-XRT refined analysis
- GRB 100518A: Swift target of opportunity observation of the INTEGRAL burst
- Swift-BAT trigger 422437 is not anything astrophysical
- Swift Trigger 422437 is probably not a GRB
- GRB 100514A: optical afterglow confirmation
- GRB 100514A: Swift/UVOT Observations
- GRB 100514A: Swift XRT refined analysis
- GRB 100514A: MASTER-Net optical observations
- GRB 100514A: Enhanced Swift-XRT position
- GRB 100514A: Swift-BAT refined analysis
- GRB 100514A: Faulkes Telescope South observations
- GRB 100514A: Swift detection of a burst
- GRB 100513A: Faulkes Telescope South observations
- GRB 100513A: Swift/UVOT upper limits
- GRB 100513A, RIMOTS optical upper limits
- GRB 100513A: Swift XRT refined analysis
- GRB 100513A: Swift-BAT refined analysis
- GRB 100513A: Enhanced Swift-XRT position
- GRB 100513A: PAIRITEL NIR afterglow candidate
- GRB 100513A: Swift detection of a burst
- GRB 100511A: Super-LOTIS early observations
- Swift-BAT trigger 421695 is likely not astrophysical
- GRB 100511A, RIMOTS optical upper limits
- Trigger 421695: Swift detection of a possible burst
- GRB100508A: Further Swift/UVOT Observations
- GRB 100508A: GROND Detection of the optical afterglow
- GRB 100508A: Swift-XRT Refined analysis
- GRB 100508A: Swift-BAT refined analysis
- GRB 100508A: Enhanced Swift-XRT position
- GRB100508A: Swift/UVOT Detection of the Afterglow
- GRB 100508A: ROTSE-III Optical Limits
- GRB 100508A: Swift detection of a burst
- Swift-BAT refined analysis of trigger 421262
- GRB 100504A: Fermi GBM observation
- An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
- GRB 100504A: Swift/UVOT Observations
- GRB 100418A: Flattening of the Swift/UVOT Optical Light Curve
- GRB 100504A: Swift-XRT refined analysis
- GRB 100504A: Enhanced Swift-XRT position
- GRB 100504A: GROND Upper limits
- GRB 100504A: Swift-BAT refined analysis
- GRB 100504A: UVOT-enhanced XRT position
- GRB 100504A: Swift detection of a burst
- Swift-BAT trigger 421072 is not astrophyical
- INTEGRAL observations of Swift GRB trigger 421072
- GRB100423A : Suzaku WAM observation of the prompt emission
- Trigger 421072: Possible Swift detection of a GRB or transient
- GRB 100420A: Terskol optical upper limit
- GRB 100427A: Swift XRT and UVOT Upper Limits
- GRB 100427A: Fermi GBM detection
- GRB 100427A detected in ground analysis of Swift BAT data
- Konus-Wind observation of GRB 100423A
- GRB 100423A: CrAO optical observations
- GRB 100418A: Terskol optical observations
- GRB 100424A: CrAO optical observations
- GRB 100425A: Swift XRT refined analysis
- GRB100425A: Swift/UVOT Upper Limits
- GRB 100424A: Swift/UVOT Upper Limits
- GRB 100425A: Enhanced Swift-XRT position
- GRB 100425A: Swift-BAT refined analysis
- GRB 100425A: GROND afterglow observation
- GRB 100424A: D50 optical limits
- GRB 100424A : Lulin early z'-band upper limit
- GRB 100424A: GROND Upper Limits
- GRB 100424A: PAIRITEL NIR Upper Limits
- GRB 100424A: Swift-XRT refined analysis
- GRB 100425A: Swift detection of a burst
- GRB 100424A, Swift-BAT refined analysis
- GRB 100424A: Enhanced Swift-XRT position
- GRB 100424A: Prompt enhanced Swift-XRT position.
- GRB 100424A: Swift detection of a burst