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"24383 results found.
- Swift/BAT trigger #250033 is due to a known source during loss of
- GRB 061213: MASTER-VWF-Kislovodsk optical candidate
- GRB 061213: MASTER-VWF-Kislovodsk observations
- GRB 061210: Gemini/GMOS Observations
- GRB 061210, Swift-BAT refined analysis of the SHB
- Optical Afterglow observations of GRB 061126
- GRB 060926: MASTER: discovery of the optical flare
- Corrections for Swift/UVOT Exposure Times for GRBs 061110B and 061121
- GRB 061201: SOAR Confirmation of Candidate Afterglow
- GRB 061202: Swift XRT refined analysis
- Konus-Wind observation of GRB 061201
- GRB061202: optical/NIR observations with REM
- GRB061202: Swift/UVOT Upper Limits
- GRB 061202, Swift-BAT refined analysis
- GRB 061201: Swift XRT Team refined analysis
- GRB 061201, Swift-BAT refined analysis of the SHB
- GRB 061121, SMARTS optical/IR observations
- GRB061121: optical observations
- GRB 061126: optical observation
- RHESSI Spectrum of GRB061126
- GRB 061126: Swift/UVOT Observations
- GRB 061126, Swift-BAT refined analysis
- GRB 061126: SARA Observations
- GRB 061126: Faulkes Telescope North Optical Observations
- GRB 061121: MDM Continued Monitoring
- GRB 061121: MDM Continuing Optical Decay
- GRB061121: optical observations
- GRB 061122: Candidate Optical Afterglow
- GRB 061121: MDM Optical Decay
- GRB061122: Swift/UVOT Optical Observations
- Konus-Wind observation of GRB 061122
- GRB 061121: MDM Optical Observations
- RHESSI Spectrum of GRB061121
- INTEGRAL results on GRB 061122
- GRB 061122A: a long GRB detected by INTEGRAL
- GRB 061121: Swift/UVOT Observations
- GRB 061121, Swift-BAT refined analysis
- GRB061121, optical observation
- GRB 061121: Optical observation at the KANATA 1.5m telescope
- GRB 061121: Faulkes Telescope North Optical Observation
- GRB 061121: ROTSE-III Confirmation of Optical Counterpart
- GRB 050915B: optical afterglow
- GRB 060111B: Swift UVOT Refined Magnitudes
- Swift/UVOT Upper Limits for GRB061110b
- Swift/UVOT Upper Limits for GRB061110a
- GRB 061110A - VLT tentative redshift
- GRB 061110B, Swift-BAT refined analysis
- GRB 061110A: Swift XRT refined analysis
- GRB 061110B: Swift/XRT position
- GRB 061110B : Liverpool Telescope Optical Afterglow Detection
- GRB 061110A, Swift-BAT refined analysis
- GRB 061110: ROTSE-III Optical Limits
- GRB 061109: optical observation
- GRB061028: MAGIC telescope GeV observation
- GRB 061028: Swift/XRT Astrometry Correction
- GRB 061004: Further VLT/NTT observations
- GRB 061028: Optical R passband observations
- GRB 061102B: Swift detection of a possible burst
- GRB 061102, Swift-BAT refined analysis
- GRB 061004: Swift/XRT Astrometry Correction
- GRB 060801: Swift/XRT Astrometry Correction
- GRB 061028, Swift-BAT refined analysis
- GRB 061027, Swift refined analysis of a possible burst
- GRB061025: Swift/UVOT observations
- GRB 061025: ROTSE-III Optical Limits
- GRB 061025: a long GRB detected by INTEGRAL
- Swift XRT boresight update
- GRB 061021 - VLT spectrum without lines
- GRB 061021: Swift/UVOT Observation
- GRB 061021, Swift-BAT refined analysis
- GRB060904b: optical observations
- GRB061019: optical observations
- GRB 061019: dust-scattered X-ray halo detected in Swift/XRT
- GRB 061019: SMARTS afterglow confirmation
- GRB061019: Swift XRT refined analysis
- GRB 061019, Swift-BAT refined analysis
- GRB061019: Swift/XRT position
- GRB 060825: GORT Observations
- GRB 061007: RHESSI Spectral Fit
- GRB 061007: Suzaku/WAM observation of the prompt emission
- Konus-Wind observation of GRB 061007
- GRB 060928: Confirmation of the X-ray afterglow detected by Swift
- GRB061007: Swift UVOT followup observations
- GRB 061006 : Suzaku/WAM observation of the prompt emission
- GRB 061007: Swift-BAT refined analysis
- GRB 061006: Swift/UVOT optical observations
- GRB 061007 - FTS early brightening and power law decay
- GRB 061007 - Faulkes Telescope South Afterglow Confirmation
- GRB 061007: ROTSE-III Detection of Optical Counterpart
- GRB 061006: Swift-BAT refined analysis of the short-hard burst
- GRB 061006: Swift-XRT Team Refined Analysis
- GRB 060930: near-IR afterglow candidate retraction
- GRB 061004: Swift-XRT Team Refined Analysis
- GRB 061004, Swift BAT refined analysis
- Konus-Wind observation of GRB 060928
- GRB 060928: Suzaku/WAM observation of the prompt emission
- GRB 060928: Swift observations
- GRB 060928: RHESSI Spectral Fit
- GRB 061002, Swift-BAT refined analysis
- GRB061002: MASTER-VWF-Kislovodsk observations