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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').

9 results found.

  1. GRB 130427B: MITSuME Ishigakijima upper limits
  2. GRB 130427B: RATIR Optical and NIR Observations
  3. GRB 130427B: Tentative VLT/X-shooter redshift
  4. GRB 130427B: Swift-XRT refined Analysis
  5. GRB 130427B: MITSuME Okayama upper limits
  6. GRB 130427B: Swift-BAT refined analysis
  7. GRB 130427B: Enhanced Swift-XRT position
  8. GRB 130427B: Faulkes Telescope North afterglow detection
  9. GRB 130427B: Swift detection of a burst with optical counterpart

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