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"2983 results found.
- GRB 090814: Swift detection of a burst
- GRB 090807B: Fermi GBM detection
- IPN Triangulation and Konus-Wind observaions of GRB090727B
- GRB 090727: GRT Optical Observation
- IPN Triangulation of bright GRB 090720B
- GRB 090715B: MASTER optical limit
- Konus-Wind and Konus-RF observations of GRB 090715B
- GRB 090709A: P60 Observations
- GRB 090618, Swift-BAT refined spectral analysis
- GRB 090530: RTT150 Optical Observation
- GRB090529B: ROVOR Upper Limits
- GRB 090531: Swift-BAT refined analysis
- GRB 090530: break in light curve
- GRB 090530: NOT optical observations
- GRB090530: Swift/UVOT afterglow detection
- GRB 090530A: ROTSE-III Detection of Optical Counterpart
- GRB 090530: Swift detection of a burst with an optical counterpart
- GRB 090520B: Fermi GBM detection
- GRB 090519, Swift-BAT refined analysis
- GRB 090515: Lick Upper Limits
- GRB 090515: Swift-BAT refined spectral analysis
- Fermi Gamma-ray Burst Monitor trigger 263649437 is not a GRB
- GRB 090424: optical observations
- GRB 090418A BVRcIc field calibration
- GRB 090429B: Swift-BAT refined analysis
- GRB 090424: Continued R-band monitoring
- GRB 090425: Fermi GBM detection
- GRB 090426, RIMOTS optical upper limits
- GRB 090426: Swift detection of a burst with an optical counterpart
- GRB090424: BVRI/R-band detection after 15 hrs burst
- GRB 090424: Swift-BAT refined analysis
- GRB090418A Rc-band photometry
- GRB 090423: Swift-BAT refined analysis
- GRB 090423: Faulkes Telescope South observations
- GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis
- GRB 090418A: optical observations
- GRB 090418A: Swift/UVOT Observations
- VLA radio detection of GRB 090418
- GRB 090418: Swift detection of a burst with optical afterglow
- GRB 090418 OA candidate
- GRB 090417B: Swift-BAT refined analysis
- GRB 090417A: Swift-BAT refined analysis
- GRB 090410: Suzaku WAM observation of the prompt emission
- GRB 090410: MITSuME optical upper limits
- GRB 090410: Swift detection of a burst
- GRB 090404: NOT observations
- GRB 090404: Swift detection of a burst
- GRB 090401B: Swift-BAT refined analysis
- GRB 090401B: Swift detection of a burst
- GRB 090320B: Fermi GBM detection.
- IPN Triangulation of GRB090315 and Tupi Detection of Muon Increase
- GRB 090308: Swift detection of a burst
- GRB 090306B: Burst detection from Swift-BAT slew data
- Konus-RF catches first GRB and SGR bursts
- GRB 090301A: Swift-BAT refined analysis
- IPN localization of GRB 090217
- SGR activity seen by BAT during ICSP Ionospheric Events
- GRB 090201: Swift-BAT refined analysis
- AXP 1E1547.0-5408: RHESSI observations up to 400 keV
- AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
- GRB 090112: Fermi GBM detection
- GRB 081224: Suzaku WAM observation of the prompt emission
- GRB 081226: GROND afterglow candidate
- GRB 081222, Swift-BAT refined analysis
- GRB 081221, Swift-BAT refined analysis
- IPN localization of short hard GRB 081216
- GRB 081203A: Optical observations of Xinglong TNT telescope
- GRB 081203A: Swift-BAT refined analysis
- GRB 081203: Swift detection of a burst with a bright optical counterpart
- GRB 081128: Swift-BAT refined analysis
- GRB081121: Refined Swift/UVOT observations
- GRB 081121: Swift-BAT refined analysis
- GRB081121: Swift/UVOT observations
- GRB 081121: ROTSE-III Detection of Optical Counterpart
- GRB081118 : optical upper limit
- GRB 081024C: Fermi Gamma-ray Burst Monitor detection
- SGR 0623-0006 or GRB 081101: Swift-BAT/-XRT refined analysis
- GRB 081028, Swift-BAT refined analysis
- Swift detection of a possible burst (trigger 332287)
- Detection of flare star Algol in Swift-BAT slew data
- GRB 081008: Galaxy associated with z=1.967 absorber
- Swift-BAT triggered on the flare star Algol
- GRB 081008 optical upper limit
- GRB 081011: Swift/XRT detection
- GRB081008: Swift/UVOT observations
- GRB 081008: Swift detection of a burst with optical afterglow
- GRB 081008: ROTSE-III Detection of Optical Counterpart
- GRB 081007: Swift detection of a burst with optical afterglow
- Trigger 324561: IGR J08408-4503 detected by Swift
- GRB 080916A: GROND lightcurve
- GRB 080916C: GROND Detection of the Optical Afterglow Candidate
- GRB080916A: Refined Swift/UVOT Observations
- GRB 080916A, Swift-BAT refined analysis
- GRB 080916: REM detection of the NIR afterglow
- GRB 080916: REM candidate afterglow
- GRB 080916: Swift detection of a burst with optical afterglow
- GRB 080915B, Swift-BAT refined analysis
- GRB 080913, Swift-BAT refined analysis
- Swift-BAT/-XRT refined analysis on trigger 324362 (LS I +61 303)
- GRB 080905B: Watcher optical detection