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"19596 results found.
- GRB 140419A: KAIT Refined Analysis
- Swift Trigger 596641 is not a GRB
- Konus-Wind observation of GRB 140419A
- GRB 140419A, Optical Observations
- GRB 140419A: Swift UVOT refined analysis
- GRB 140419A: P60 Observations
- GRB 140419A: Swift-XRT refined Analysis
- GRB 140419A: Swift-BAT refined analysis
- GRB 140419A: Enhanced Swift-XRT position
- GRB140419A: UVOT detects fading afterglow in white but not in u filter
- GRB 140419A: ROTSE-III Detection of Optical Counterpart
- GRB 140419A (Swift trigger 596426) : KAIT optical candidate
- GRB 140419A: Swift detection of a burst with optical afterglow
- GRB 140414A: Swift/UVOT Upper Limit
- GRB 140414A: Swift-XRT observations
- GRB 140414A: Swift-BAT refined analysis
- GRB 140414A: Short burst found in ground analysis of BAT slew data
- GRB 140413A: Swift/UVOT Observations of the Optical Afterglow
- GRB 140412A: Swift/UVOT Upper Limits
- Konus-Wind observation of GRB 140413A
- GRB 140413A: Swift-XRT refined Analysis
- GRB 140413A: Swift-BAT refined analysis
- GRB 140412A: Swift-XRT refined Analysis
- GRB 140412A: Swift-BAT refined analysis
- GRB 140413A: TAROT La Silla observatory optical observations
- GRB 140413A: Swift-XRT observations
- GRB 140412A: Enhanced Swift-XRT position
- GRB 140413A: GROND afterglow candidate
- Swift Trigger 595616: a possible GRB
- GRB 140412A: Swift detection of a burst
- GRB 140408A: 1.5m OSN optical upper limit
- Swift Trigger 595345 is not an astrophysical source
- Swift-BAT trigger 595162 is noise
- GRB 140408A: RATIR Optical Upper Limits
- GRB 140408A: Swift-BAT refined analysis
- GRB 140408A: GROND Detection of an Afterglow Candidate
- GRB 140408A: Swift/UVOT Upper Limits
- GRB 140408A: Swift-XRT refined Analysis
- GRB 140408A: Enhanced Swift-XRT position
- GRB 140408A: Fermi GBM detection
- Swift Trigger 595162: a possible GRB
- GRB 140408A: Swift detection of a burst
- GRB 140402A: Deep limit on the optical afterglow from Magellan observations
- GRB 140402A: Swift/UVOT Upper Limits
- GRB 140331A: Continued RATIR Optical and NIR Observations
- GRB 140402A: Swift-XRT observations
- GRB 140402A: MASTER optical observations
- GRB 140402A BAT refined analysis
- GRB 140402A: Marginal BAT detection
- GRB 140402A: Fermi-LAT detection of a burst
- Swift trigger 594286: Is likely a noise trigger
- GRB 140331A: Swift-XRT refined Analysis
- GRB 140301A: Zadko observatory - Gingin optical observations
- GRB 140331A: Swift-BAT refined analysis
- GRB 140331A: Swift/UVOT Upper Limits
- GRB 140302A: TAROT La Silla observatory optical observations
- GRB 140323A: Zadko observatory - Gingin optical observations
- GRB 140331A: Zadko observatory - Gingin optical observations
- GRB 140129B: AAO optical upper limit
- GRB 140129A: Mondy optical observations
- GRB 140331A: Enhanced Swift-XRT position
- GRB 140331A: RATIR Optical and NIR Observations
- GRB 140331A: Swift detection of a burst
- GRB 140330A: Fermi-LAT Detection
- Swift trigger 593744: detection of a flare from UV Cet
- GRB 140323A : Suzaku WAM observation of the prompt emission
- Konus-Wind observation of GRB 140323A
- GRB 140323A: Fermi-LAT detection
- GRB 140323A: Swift-XRT refined Analysis
- GRB 140323A: Fermi GBM observation
- GRB 140323A: BOOTES-3 optical upper limit.
- GRB 140323A: Swift/UVOT Upper Limits
- GRB 140323A: Swift-BAT refined analysis
- GRB 140323A: Enhanced Swift-XRT position
- GRB 140323A: Swift detection of a burst
- GRB 140320A: RATIR Optical and NIR Observations
- IPN Triangulation of very intense GRB 140320D
- GRB 140320C: Swift/UVOT Upper Limits
- GRB 140320A: Swift-BAT refined analysis
- GRB 140320B: Swift/UVOT Upper Limits
- GRB 140320A: Swift/UVOT Upper Limits
- GRB 140320C: Swift-XRT observations
- GRB 140320A: Confirmation of a fading X-ray afterglow
- GRB 140320C: Swift-XRT detection of the X-ray afterglow
- GRB 140320A: Fermi GBM detection
- GRB 140320B: Swift-XRT detection of the afterglow
- GRB 140320A: Enhanced Swift-XRT position
- GRB 140320A: Swift-XRT detection of an afterglow candidate
- Swift Trigger 592558 is not an astrophysical source
- GRB 140320A: Fermi GBM observations suggest a short GRB
- GRB 140320A: Swift detection of a burst
- GRB 140318A: Mondy optical limit
- GRB 140318A: Swift/UVOT Upper Limits
- GRB 140318A: Swift-BAT refined analysis
- GRB 140311B: Mondy optical limit
- GRB 140311A: Mondy optical limits
- GRB 140318A: Swift-XRT refined Analysis
- GRB 140318A: Liverpool Telescope optical observations
- GRB 140318A: Enhanced Swift-XRT position
- GRB140318A: Discovery Channel Telescope Optical Detection