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"19603 results found.
- GRB 150801A: Tiled Swift observations
- GRB 150724B: Swift-XRT afterglow detection
- GRB150724B: Retraction of the uvot detection
- GRB 150728A: TSHAO optical observations
- GRB 150728A: RATIR Optical Observations
- GRB 150728A: AAO optical observations
- GRB 150728A: Swift-XRT refined Analysis
- GRB 150728A: Swift/UVOT Upper Limits
- GRB 150728A: Swift-BAT refined analysis
- GRB 150728A: FTN observations
- GRB 150727A: RATIR Optical Observations
- GRB 150728A: Enhanced Swift-XRT position
- GRB 150728A: Swift detection of a GRB
- GRB 150727A: Swift-BAT refined analysis
- GRB 150727A: Swift/UVOT Detection
- GRB 150727A: Swift-XRT refined Analysis
- GRB 150727A: Fermi GBM detection
- GRB 150727A: Enhanced Swift-XRT position
- GRB 150724B: MASTER upper limit
- GRB 150727A: Swift detection of a burst with an optical counterpart
- GRB 150724B: Swift/UVOT Detection
- GRB 150724B: RATIR Optical Observations
- Swift Trigger 650408 is not a burst
- Swift 650221/IGR J00291+5934: Liverpool Telescope observations
- GRB 150724B: Swift-XRT observations
- GRB 150724B: Swift ToO observations
- IGR J00291+5934, Swift-BAT refined analysis
- GRB 150724B: Fermi-LAT detection
- Swift Trigger 650221 / IGR J00291+5934: MASTER-IAC OT observations
- Trigger 650221: Swift detection of a IGR J00291+5934
- Correction to GCN 18059: Parameterisation of Swift-XRT light curve
- GRB 150724A: Swift-XRT refined Analysis
- Swift IGR J00291+5934: MASTER Optical flare detection
- GRB 150724A: Swift/UVOT Upper Limits
- IGR J00291+5934: Swift-BAT refined analysis
- GRB 150724A: Swift-BAT refined analysis
- GRB 150724A: Enhanced Swift-XRT position
- SGR 1E 1841-045 (Swift trigger 649113): Terskol upper limit
- GRB 150724A: Prompt enhanced Swift-XRT position
- Trigger 650140: Swift detection of IGR J00291+5934
- GRB 150724A: Swift detection of a burst
- GRB 150722A: Swift-BAT refined analysis
- GRB 150722A: Swift-XRT refined Analysis
- GRB 150722A: Swift/UVOT Upper Limits
- GRB 150720A: Swift/UVOT Upper Limits
- GRB 150722A: Enhanced Swift-XRT position
- GRB 150722A: Swift-XRT observations
- GRB 150722A: Swift detection of a burst
- GRB 150720A: Enhanced Swift-XRT position
- GRB 150720A: Swift-XRT refined Analysis
- GRB 150720A: Swift-BAT refined analysis
- Swift Trigger 649706: a possible GRB or bright Galactic transient
- GRB 150716A: KAIT Optical Upper Limit
- GRB 150716A: Swift-BAT refined analysis
- GRB 150716A: Swift/UVOT Upper Limits
- Swift trigger 649143 is not AX J1619.4-4945 or other astrophysical source
- GRB 150716A: Swift-XRT refined Analysis
- GRB 150716A: P60 Candidate Optical Afterglow
- GRB 150716A: RATIR Optical Observations
- GRB 150716A: Swift detection of a burst
- Trigger 649143: Swift detection of AX J1619.4-4945
- Trigger 649113: Swift detection of SGR 1E 1841-045
- GRB 150710B: Swift-XRT afterglow detection
- GRB 150711A: Swift-BAT refined analysis
- Konus-Wind observation of GRB 150710B
- GRB 150710B: Swift-XRT and Swift-UVOT observations
- GRB 150711A: Swift/UVOT Upper Limits
- GRB 150711A: Swift-XRT refined Analysis
- GRB 150711A: Fermi GBM detection
- GRB 150710B refined analysis
- GRB 150711A: Enhanced Swift-XRT position
- GRB 150711A: Swift detection of a burst
- GRB 150710B: Swift ToO observations
- GRB 150710B detected in ground analysis of BAT data
- GRB 150710A: Swift/UVOT Upper Limits
- GRB 150710A: host galaxy for Swift XRT second candidate
- Swift-XRT observations of GRB 150710A
- Confirmation that Swift trigger 648422 is not an astrophysical source
- Konus-Wind observation of GRB 150710A (Swift trigger 648437)
- GRB 150710A: Swift-BAT refined analysis
- GRB 150710A: RATIR Observations
- Swift trigger 648437: A GRB or a burst from 1RXS J125754.7+141850
- Swift Trigger 648422: Swift-XRT observations
- Trigger 648422: Swift possible detection of a source in NGC4552
- IPN Triangulation of GRB 150702A
- GRB 150702A: Swift-XRT observations
- GRB 150702A: Swift ToO observations
- GRB 150702A: Fermi-LAT detection
- GRB 150622A: Swift-XRT afterglow detection
- Swift Trigger 647642 is probably not an astrophysical source
- GRB 150626B, Swift-BAT refined analysis
- V404 Cyg activity (Swift, Fermi, INTGRAL, KONUS, MAXI detection): optical observations in TSHAO, Khureltogot, and AAO
- GRB 150627A: Swift/UVOT Detection
- GRB 150627A: Swift-XRT afterglow detection
- GRB 150626B: Swift-XRT refined Analysis
- GRB 150626A: Swift-BAT refined analysis
- GRB 150627A: Swift ToO observations
- GRB 150627A: Fermi-LAT detection
- GRB 150626B: Swift/UVOT Upper Limits
- GRB 150626B: Enhanced Swift-XRT position