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"- GRB 140709A: 10.4m GTC optical decay
- GRB 140710A: Swift detection of a burst
- GRB 140709B: Swift-XRT refined Analysis
- GRB 140709B: Fermi GBM detection
- GRB 140709B: Swift-BAT refined analysis
- GRB 140709A : Virtual Telescope optical observations
- GRB 140709B: Khureltogot optical upper limit
- GRB 140709B: OSN optical limit
- GRB 140709B: Enhanced Swift-XRT position
- GRB 140709A: Fermi GBM detection
- GRB 140709A: BOOTES-2 and OSN optical observations
- GRB 140709A, Swift-BAT refined analysis
- GRB 140709B: MASTER optical observation
- GRB 140709B: Swift detection of a burst
- GRB 140709A: Swift-XRT refined Analysis
- GRB 140709A: Swift/UVOT Upper Limits
- GRB 140709A - UVOT-enhanced XRT position
- GRB 140709A: RATIR Optical and NIR Observations
- GRB 140709A: Swift detection of a burst
- Fermi GBM trigger 140708682 is not a GRB
- GRB 140705A: Nishi-Harima NIR upper limits
- GRB 140703A: AMI 15 GHz detection
- GRB 140705A / SGR 1935+2154: VLA 6 GHz observations
- GRB 140706A: Swift/UVOT Detection
- GRB 140703A: Swift/UVOT Upper Limits
- GRB 140706A: Swift-BAT refined analysis
- GRB 140706A: Swift-XRT refined Analysis
- GRB 140706A: Fermi GBM detection
- GRB 140703A: AAO optical observations
- Pre-discovery observations of SGR 1935+2154 in Swift archival data
- GRB140706A: GROND detection of the Optical/NIR afterglow
- GRB 140705A / SGR 1935+2154: Probable association with supernova remnant G57.2+0.8
- GRB 140706A: Enhanced Swift-XRT position
- GRB 140706A: Swift detection of a burst with an optical counterpart
- SGR 1935+2154: Swift-BAT observations of additional short soft events
- GRB 140705A / SGR 1935+2154: FTN observations
- GRB 140705A / SGR 1935+2154: Optical observations from 10.4m GTC
- GRB 140705A: KAIT Optical Upper Limit
- GRB 140705A: MITSuME Ishigakijima upper limits
- GRB 140705A: Swift-XRT refined Analysis
- GRB 140705A: MITSuME Okayama upper limits
- GRB 140705A: Swift/UVOT Upper Limits
- GRB 140705A: Swift-BAT refined analysis of a possible newly discovered SGR 1935+2154
- GRB 140705A: Enhanced Swift-XRT position
- GRB 140705A: Swift detection of a short burst
- GRB 140621A: Suzaku WAM observation of the prompt emission
- GRB 140629A: SAO RAS Rc band photometry
- GRB 140629A, Optical observations
- GRB 140703A: VLA K-band detection
- GRB 140703A: CARMA 3mm detection
- GRB 140703A: P60 observations of a red, slowly-fading afterglow
- GRB 140703A: RATIR Optical and NIR Observations
- GRB 140703A: Fermi GBM detection
- GRB 140703A: Monte Agliale Observatory optical observations
- GRB 140703A: Swift-XRT refined Analysis
- GRB 140703A: Swift-BAT refined analysis
- Correction to GCN 16507: GRB 140703A!
- GRB 140703A: MASTER optical observations
- GRB 140703A: Enhanced Swift-XRT position
- GRB140703A: 10.4m GTC redshift
- GRB 140703A: BOOTES-2 and OSN optical observations
- GRB 140703A: Swift detection of a burst
- GRB 140619C: Suzaku WAM observation of the prompt emission
- GRB 140629A: MITSuME Akeno Optical observation
- GRB 140629A: MASTER-Net preliminary light curve
- GRB 140629A: SAO RAS monitoring
- GRB 140629A: additional P60 observations
- Fermi 425667201: optical counterpart search
- GRB 140629A: Nishi-Harima NIR Observations
- Konus-Wind observation of GRB 140629A
- GRB 140629A: Swift/UVOT Detection
- GRB 140629A: TNG redshift confirmation
- GRB140629A: VATT optical observations
- GRB 140629A: P60 observations
- GRB 140629A: Swift-XRT refined Analysis
- GRB 140629A: BTA redshift
- GRB 140629A: MITSuME Ishigakijima Optical Observation
- GRB140629A: Kanata/HOWPol optical observation
- GRB 140629A: T100 observations
- GRB 140629A: NOT optical observations
- GRB 140629A: KWFC z-band photometry
- GRB 140629A : Virtual Telescope optical observations
- GRB 140629A: RTT150 optical observations
- GRB 140629A: Swift-BAT refined analysis
- GRB 140629A : Xinglong TNT optical observation
- GRB 140629A: Enhanced Swift-XRT position
- GRB 140629A: MASTER OT detection
- GRB 140629A: Swift detection of a burst with an optical counterpart
- GRB 140628A: GROND observation of the afterglow
- GRB 140628A: Swift-XRT refined Analysis
- GRB 140628A: Zadko observatory - Gingin optical observations
- GRB 140628A: Swift-BAT refined analysis
- GRB 140628A: Swift/UVOT Detection
- GRB 140628A: Swift/UVOT Detection
- GRB 140628A: Swift-XRT afterglow detection and enhanced position
- GRB 140626A: TAROT La Silla observatory optical observations
- GRB 140622A: TAROT La Silla observatory optical observations
- GRB 140628A: Swift detection of a burst
- GRB 140619B: Magellan near-infrared observations
- Swift Trigger 602668: XRT and UVOT confirm is not astrophysical source