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"28054 results found.
- GRB 150523A: Swift/UVOT Detection
- GRB 150513A: request for X-ray follow up
- GRB 150523A: LCOGT FTS afterglow confirmation
- GRB 150523A: LCOGT Cerro-Tololo optical afterglow candidate
- GRB 150523A Swift-XRT afterglow detection
- GRB 150523A: Fermi GBM detection
- Swift trigger 641332 is probably not an astrophysical source
- GRB 150518A: Continued RATIR optical observations
- GRB 150518A: MAXI-GSC further analysis
- GRB 150518A: Mondy optical observations
- GRB 150518A: MASTER-net before, early and after optical stereoscopic observations with possible MP discovery inside MAXI error box
- GRB 150518A: Swift-XRT follow-up observations
- GRB 150518A: SAO RAS optical observations
- GRB 150518A: RATIR optical observations
- GRB 150518A: GMG observation
- GRB 150518A: Xinglong2.16m optical afterglow detection
- Swift/UVOT observations of GRB150518A
- GRB 150518A: Swift-XRT afterglow detection
- GRB 150518A: MAXI/GSC detection
- GRB 150514A: GROND Bright Afterglow Confirmation
- GRB 150514A: Swift/UVOT Detection
- GRB 150514A: Swift-XRT afterglow detection
- GRB 150513A: Swift-BAT refined analysis
- GRB 150513A: Fermi GBM detection
- GRB 150512A: iPTF Optical Observations
- GRB 150510A: Fermi GBM detection
- GRB 150424A: 9.8 GHz VLA detection
- GRB 150423A: GMG observation limit
- Konus-Wind observation of GRB 150428A
- GRB 150423A: Chandra X-ray Observation
- Swift Trigger 639636: a possible GRB
- GRB 150430A: GROND Upper Limits
- GRB 150430A: Swift-BAT refined analysis
- GRB 150430A: Swift-XRT refined Analysis
- GRB 150430A: MAXI/GSC detection
- GRB 150430A: Swift/UVOT Upper Limits
- GRB 150430A: Swift detection of a burst
- GRB 150428B: IRSF NIR upper limits
- GRB 150428B: Swift/UVOT Upper Limits
- GRB 150428C: Swift-XRT observations
- GRB 150428A: Swift/UVOT Upper Limits
- GRB 150413A: CrAO optical observations
- GRB 150426A: Fermi GBM detection
- GRB 150428B: Swift-XRT refined Analysis
- GRB 150428A: Swift-XRT refined Analysis
- GRB 150428B: Swift-BAT refined analysis
- GRB 150428A: Swift-BAT refined analysis
- GRB 150428B: Enhanced Swift-XRT position
- GRB 150428C/MAXI J0400+678: MAXI/GSC detection
- GRB 150428A: Danish1.56m optical observations
- GRB 150428A: RATIR optical observations
- GRB 150428A: P60 observations
- GRB 150428A: Enhanced Swift-XRT position
- GRB 150428A: GROND Dark Burst Host Candidate
- GRB 150428B: Swift detection of a burst
- GRB 150428A: Swift detection of a burst
- Trigger 639199: Swift detection of IGRJ16418-4532
- GRB 150424A: RATIR Observations
- GRB 150424A: Swift-BAT refined analysis
- GRB 150424A: Swift-XRT refined Analysis
- GRB 150424A: GROND detects strong fading
- GRB 150423A: Continued RATIR optical afterglow monitoring
- GRB 150424A: Swift/UVOT Observations
- GRB 150423A: TSHAO optical observations
- GRB 150424A: Enhanced Swift-XRT position
- GRB 150423A: WHT observations
- GRB 150424B: MAXI/GSC detection
- GRB 150424A: Keck detection of optical afterglow
- GRB 150424A: Swift detection of a short burst
- GRB 150423A: MITSuME Okayama upper limits
- GRB 150423A: UKIRT NIR observations
- GRB 150423A: Swift-BAT refined analysis
- GRB 150423A: Swift/UVOT Upper Limits
- GRB 150423A: VLT detection
- GRB 150423A: Swift-XRT refined Analysis
- GRB 150423A: RATIR optical afterglow monitoring
- GRB 150423A: Enhanced Swift-XRT position
- GRB 150422A: Fermi GBM detection
- GRB 150423A: Keck optical afterglow confirmation
- GRB 150423A: GROND afterglow candidate
- GRB 150413A: Konus-Wind and Swift/BAT joint spectral analysis
- GRB 150423A: GROND observation
- GRB 150423A: Swift detection of a short burst
- Konus-Wind observation of GRB 150418A
- GRB150418A: Swift/UVOT did not detect a new source
- Further Swift XRT observations of GRB 150418A
- Swift trigger 638589 is probably not an astrophysical source
- GRB 150413A: Swift-XRT observations
- GRB 150418A: Swift-XRT observations
- GRB 150413A: RTT150 optical observations
- GRB 150418A: MAXI/GSC detection
- GRB 150413A: ISON-Ussuriysk optical observations
- GRB 150416A: Fermi GBM detection
- GRB 150413A: MITSuME Akeno Optical observation
- GRB 150413A: SAO RAS observations
- LOAO B, R Observations of GRB150413A
- Swift Trigger 638217 is probably not an astrophysical source
- GRB 150416A: Fermi-LAT detection
- GRB 150413A: GMG observation
- GRB 150413A