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"16153 results found.
- GRB 061218: TAROT La Silla observatory optical observations
- GRB 061217: TAROT Calern observatory optical observations
- GRB 061218: TORTOREM optical upper limits
- GRB 061218, SMARTS optical/IR observations
- GRB 061218: REM prompt observations
- GRB 061217, SMARTS optical observations
- GRB061217: Swift/UVOT refined analysis.
- GRB 061217: optical observations at Calar Alto
- GRB 061217: REM prompt observations
- GRB 061217: ROTSE-III Optical Limits
- GRB 061210: MDM Follow-up Observation
- GRB061210: Swift/UVOT observations
- GRB 061210: Optical sources near XRT positions
- GRB 061210 : Faulkes North Telescope optical limit
- GRB 061214(?): ROTSE-III Optical Limits
- GRB 061213: MASTER-VWF-Kislovodsk optical candidate
- GRB061201, VLT optical decay: correction
- Optical Afterglow observations of GRB 061126
- GRB061126: optical observations
- GRB 060926: MASTER: discovery of the optical flare
- GRB 061201: UVOT Observations of a Fading Optical Afterglow
- GRB 061202: TORTOREM optical upper limits
- GRB 061201: VLT optical decay
- GRB061126 : NMSU 1.0m observations
- GRB061202 optical limit by "Pi of the Sky"
- GRB061202: optical/NIR observations with REM
- GRB 061201: Swift XRT Team refined analysis
- GRB 061201: VLT optical observations
- GRB 061201: Initial UVOT Observations
- GRB 061122: GETS observation
- GRB 061121, SMARTS optical/IR observations
- INT+WFC observations of GRB 061126
- GRB 061121: Second Epoch ATCA Radio Observations
- GRB 061126: RAPTOR Optical Detection During Gamma-Ray Emission
- GRB 061121: ATCA & WSRT Radio Observations
- GRB061121: optical observations
- GRB 061126: Early Super-LOTIS Observations
- GRB 061126: optical observation
- GRB061126: Optical afterglow observations from MIRO
- GRB061126: Optical afterglow observations from MIRO
- GRB 061126: Swift/UVOT Observations
- GRB 061126: Early Detection of the IR Afterglow
- GRB 061126: Faulkes Telescope North Optical Observations
- GRB 061121: MDM Continued Monitoring
- GRB 061122: Confirmation of X-ray/Optical Afterglow
- GRB 061121: MDM Continuing Optical Decay
- GRB061121: optical observations
- GRB 061122: Candidate Optical Afterglow
- GRB 061121: MDM Optical Decay
- GRB061122: Swift/UVOT Optical Observations
- GRB 061121: ART detection in Ic
- GRB 061121: MDM Optical Observations
- GRB 061121 declared "Burst of Interest" by Swift team
- GRB 061121: Swift/UVOT Observations
- GRB061121, optical observation
- GRB 061121: Optical observation at the KANATA 1.5m telescope
- GRB 061121: Faulkes Telescope North Optical Observation
- GRB061121: Spectroscopic Redshift
- GRB061121: Keck spectroscopic observations
- GRB 061121: ROTSE-III Confirmation of Optical Counterpart
- GRB 061121: Swift detection of a bright burst with an optical counterpart
- GRB 060605: NIR Observations
- GRB 050915B: optical afterglow
- GRB 061110B: Swift XRT refined analysis
- GRB061110B: Optical observations at Crni Vrh
- GRB 061110B: NOT optical observations
- GRB 061110A: Swift XRT refined analysis
- GRB 061110B : Liverpool Telescope Optical Afterglow Detection
- GRB 061110B: TAROT Calern observatory optical observations
- GRB 061110: NOT observations
- GRB 061110 : Optical afterglow candidate
- GRB 061110: ROTSE-III Optical Limits
- GRB061110A - Optical Non-detection
- GRB 061109: optical observation
- GRB 061109: TAROT Calern observatory optical observations
- GRB061028: MAGIC telescope GeV observation
- GRB 061027: TAROT La Silla observatory optical observations
- GRB 061007: Third Epoch ATCA Radio Observations
- GRB061019: second epoch CrAO observations
- GRB 061028: Swift/XRT Astrometry Correction
- GRB 061102: Swift/UVOT Magnitude Upper Limits
- GRB 061004: Further VLT/NTT observations
- GRB 061028: Optical R passband observations
- GRB 061004: Swift/XRT Astrometry Correction
- GRB 060801: Swift/XRT Astrometry Correction
- GRB 061028: SARA upper limit
- GRB 061028: TAROT Calern observatory late optical observations
- GRB 061028: TAROT Calern observatory optical observations
- GRB061025: ROTSE-III Confirmation of Optical Counterpart
- GRB 061025: REM observations
- GRB 061025: ROTSE-III Optical Limits
- GRB 061021: Swift/UVOT Observation
- GRB060904b: optical observations
- GRB061019: optical observations
- GRB061019: optical observations
- GRB 061019: dust-scattered X-ray halo detected in Swift/XRT
- GRB 060930: MARGE Optical Limits
- GRB 061019: Swift/UVOT upper limit
- GRB 061019: SMARTS afterglow confirmation
- GRB 061019: TAROT La Silla observatory optical observations