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"28082 results found.
- GRB110530A: MITSuME Okayama Optical Observation
- GRB 110530A: Swift-BAT refined analysis
- GRB 110529A: Fermi GBM detection
- GRB 110530A: Swift detection of a burst with an optical afterglow
- LAT Observations of GRB110529A
- EVLA afterglow limits on the high z GRB090429B
- Swift J1644+57/GRB 110328A, Additional HST Observations
- GRB 110521A: MASTER prompt optical limit
- GRB 110521A: Swift/UVOT Upper Limits
- GRB 110521A: Swift-XRT refined analysis
- GRB 110520A: NOT optical follow-ups
- GRB 110521A - NOT optical observation
- GRB 110521A: Swift-BAT refined analysis
- GRB 110521A: Enhanced Swift-XRT position
- GRB 110521A: MASTER synchronous and early optical observations limit
- Swift/UVOT observations of GRB110520A
- GRB 110521A: Swift detection of a burst
- GRB 110520A: Swift-BAT refined analysis
- GRB 110520A: IAC80 I-band observations
- GRB 110520A: Swift-XRT refined Analysis
- GRB 110520A: Enhanced Swift-XRT position
- GRB 110520A: WHT IR observations
- GRB 110520A - NOT optical observation
- GRB 110520A: TAROT Calern observatory optical observations
- GRB 110520A: Swift detection of a burst
- IPN localization of bright GRB 110518A
- GRB 110519A, Swift-BAT refined analysis
- GRB 110519A: Swift detection of a burst
- GRB 110426A: Fermi GBM detection
- GRB 110428A: Fermi-GBM observation
- GRB 110503A: TAROT Calern observatory optical observations
- Konus-Wind observation of GRB 110503A
- GRB 110503A: optical observation in CrAO
- GRB 110503A: Centimeter observation from EVLA
- GRB 110503A: Millimeter observation from SMA
- GRB 110503A: SARA-N Observations and Photometric Calibration
- GRB 110503A: Swift/UVOT Observations
- GRB 110503A: Swift-XRT refined Analysis
- GRB 110503A: PAIRITEL NIR Detection
- GRB 110503A: Swift-BAT refined analysis
- GRB 110503A: Enhanced Swift-XRT position
- GRB 110503A: Swift detection of a burst with a bright optical counterpart
- GRB 110426A: Swift/XRT non-detection
- GRB 110428A : X-ray afterglow confirmation
- GRB 110428A: Suzaku WAM observation of the prompt emission
- GRB 110422A: optical observations in CrAO
- GRB 110428A : Swift-XRT observations
- GRB 110426A: MASTER synchronous with MAXI/GSC observations
- GRB 110422A: optical observations in CrAO, second epoch
- GRB 110422A: Suzaku WAM observation of the prompt emission
- GRB110422A: NOT optical follow-ups
- GRB 110422A: optical observations in CrAO
- GRB110422A: MITSuME Ishigakijima Optical Observation
- GRB 110422A: Further NOT observation
- GRB 110422A: Swift/UVOT Detection of optical afterglow
- GRB 110422A: Swift-XRT refined Analysis
- GRB 110422A: Enhanced Swift-XRT position
- GRB 110422A: TNG optical observations
- GRB 110422A: SAO RAS optical observations
- GRB 110422A: NOT optical observation
- GRB 110422A: Swift-BAT refined analysis
- GRB 110422A: Mondy optical observations
- GRB 110422A: Swift detection of a burst
- GRB 110420B: Swift/UVOT Upper Limits
- GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
- GRB 110420B: Swift-XRT afterglow candidate retraction
- GRB 110420B, GROND observations
- GRB 110420A Swift/UVOT Observations
- GRB 110420B: Swift-XRT afterglow candidate
- GRB 110420B: Swift-BAT refined analysis
- GRB 110420A: Swift-BAT refined analysis
- GRB 110420A: Swift-XRT refined Analysis
- GRB 110420A: Enhanced Swift-XRT position
- GRB 110420A: Swift detection of a burst with optical counterpart
- GRB110414A: MITSuME Ishigakijima Optical upper limits
- GRB 110414A: GROND upper limits
- GRB110414A: MITSuME Okayama Optical upper limits
- GRB 110414A: Swift-BAT Refined Analysis
- GRB 110414A: Swift/UVOT Upper limits
- GRB 110414A: Swift-XRT refined Analysis
- GRB 110414A: Enhanced Swift-XRT position
- GRB 110328A / Swift J164449.3+573451: WISE quiescent source upper limit
- GRB 110414A : Faulkes Telescope North observations
- GRB 110414A: Swift detection of a burst
- GRB 110411A: PAIRITEL NIR Upper Limits
- GRB 110412A: Swift-BAT refined analysis
- GRB 110411A: Swift-XRT refined Analysis
- GRB 110411A: Swift/UVOT Upper Limits
- GRB 110411A : Xinglong TNT OT candidate
- GRB 110411A, Swift-BAT refined analysis
- GRB 110411A: Enhanced Swift-XRT position
- GRB 110411A: Swift detection of a burst
- GRB 110407A: Swift-XRT refined Analysis
- GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
- GRB 110328A / Swift J164449.3+573451: optical observations
- GRB 110328A/Swift J164449.3+573451 UVOT Upper Limits
- GRB 110406A: Positional coincidence with NGC 404
- GRB110407A: UVOT Upper Limits
- GRB 110407A: GROND Detection of the Optical Afterglow
- GRB 110407A: MITSuME Okayama and Ishigakijima Optical upper limits