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"28055 results found.
- GRB 111121A: Swift-BAT refined analysis
- GRB 111117A: Chandra detection of the afterglow
- GRB 111121A: Enhanced Swift-XRT position
- GRB 111121A: Swift detection of a short hard burst
- GRB 111117A: Gemini Afterglow Limits
- GRB 111117A: optical upper limit in CrAO
- GRB 111117A: Fermi GBM observation
- GRB 111117A: TNG observations
- GRB 111117A: Swift/UVOT Upper Limits
- GRB 111117A: GROND observations
- GRB 111117A: Gemini host observation
- GRB 111117A: Swift-XRT refined Analysis
- GRB 111117A: NOT observations
- GRB 111117A: Chandra ToO observation scheduled
- GRB 111117A: Swift-BAT refined analysis of a short hard burst
- GRB 111117A: GMG upper limit
- GRB 111117A: Swift detection of a short hard burst
- GRB111107A: ATCA observations - upper limit and a possible detection
- IPN Triangulation of GRB 111113A (short/hard/intense)
- XRF 111111A/MAXI J0158-744: MAXI GSC and SSC detection of a soft X-ray transient near SMC
- GRB 111109A: Swift-XRT refined Analysis
- GRB 111109A: Swift/UVOT Photometry
- GRB 111109A: Swift-BAT refined analysis
- GRB 111109A: Enhanced Swift-XRT position
- GRB 111109A: Swift-XRT observations
- GRB 111109A: Swift detection of a burst
- GRB 111103B: optical upper limit of CrAO
- GRB 111103B: optical upper limit of Mt. Terskol observatory
- GRB 111107A: Fermi GBM observation
- Continued Skynet observations of GRB111107A
- GRB 111107A: Swift-XRT refined Analysis
- GRB 111107A: APEX submm observation
- GRB 111107A: Swift/UVOT Afterglow Analysis
- GRB 111107A: Swift-BAT refined analysis
- GRB 111107A: Enhanced Swift-XRT position
- GRB 111107A: GROND observations
- Skynet observations of GRB 111107A
- GRB 111107A: Swift detection of a burst with an optical counterpart
- GRB 111103B : WIYN 3.5m NIR observations
- GRB 111103B: Swift-XRT refined Analysis
- GRB 111103A: Fermi GBM observation
- GRB111103B Swift/UVOT Upper Limits
- GRB 111103B: Enhanced Swift-XRT position
- GRB 111103B: Swift-BAT refined analysis
- GRB 111103A: Swift-BAT refined analysis
- Trigger 506913: Swift detection of Swift J1922.7-1716 and its optical counterpart
- GRB 111103B: Swift detection of a strong burst from a GRB or Galactic source
- GRB 111029A: RAPTOR Limits During the Gamma-ray Emitting Interval
- GRB 111029A: SAO RAS optical limits
- GRB 111029A: Super-LOTIS early limits
- All GCN Circulars available in a tarfile for data mining
- GRB111029A: MITSuME Ishigakijima Optical Upper Limits
- GRB 111029A: Swift-XRT refined Analysis
- GRB 111029A: PAIRITEL NIR Upper Limits
- GRB 111026A: Swift-BAT refined analysis
- GRB 111029A: Swift/UVOT Upper Limits
- GRB 111029A: Swift-BAT refined analysis
- GRB 111029A: Enhanced Swift-XRT position
- GRB 111029A: optical upper limit
- GRB 111029A: ROTSE-III Optical Limits
- GRB 111029A: Swift detection of a burst
- GRB 111026A: Swift detection of a burst
- GRB 111022B: 10.4m GTC z'-band observations
- GRB111022B: D50 optical limit
- GRB 111020A: Chandra Observation
- GRB 111022B: BTA Optical Observations
- GRB 111022B: Swift/UVOT upper limits
- GRB 111022A: Swift/UVOT Upper Limits
- GRB 111016A: optical upper limit
- GRB 111022B, Swift-BAT refined analysis
- GRB 111022B: Swift-XRT refined Analysis
- GRB 111022A: Swift-XRT refined Analysis
- GRB 111022B: NOT observations
- GRB 111022B: Enhanced Swift-XRT position
- GRB 111022A: Swift-BAT refined analysis
- GRB 111022A: Preliminary UVOT TDRSS Non-Detection
- GRB 111022B: Swift detection of a burst
- GRB 111022A: Swift detection of a burst
- GRB 111020A: Gemini-South additional observations and limit on an optical afterglow
- GRB 111020A: EVLA observations
- GRB 111020A: Swift-XRT refined Analysis
- GRB 111020A: Swift/UVOT Upper Limits
- GRB 111020A: Faulkes Telescope South observations
- GRB 111020A: Swift-BAT refined analysis
- GRB 111020A: Enhanced Swift-XRT position
- GRB 111020A: BOOTES-3 Optical Upper Limit.
- GRB 111020A: Swift detection of a short burst
- GRB 111018A: Swift/UVOT Upper Limits
- GRB 111018A: Swift-BAT refined analysis
- GRB 111018A: Swift-XRT refined Analysis
- GRB 111018A: GROND Upper Limits
- GRB 111018A: Enhanced Swift-XRT position
- IPN Triangulation of GRB 111016B (long duration, intense)
- GRB111016A : WIYN 3.5m NIR observations
- GRB 111018A: Swift detection of a burst
- GRB 111017A: Fermi GBM Detection
- GRB111016A: D50 optical limit
- GRB 111016A: Gemini Detection of the NIR Counterpart
- GRB 111016A: Swift/UVOT Detection of a Source
- GRB 111016A: Swift-BAT refined analysis