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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 170318B: 15 GHz upper limits from AMI
  2. GRB 170318B: Swift-BAT refined analysis
  3. GRB 170318B: RATIR Optical and NIR Observations
  4. GRB 170318B: Swift/UVOT Upper Limits
  5. GRB 170318B: Swift-XRT refined Analysis
  6. GRB 170318B: Fermi GBM observation
  7. GRB 170318B: Enhanced Swift-XRT position
  8. GRB 170318B: Prompt enhanced Swift-XRT position
  9. GRB 170318B: Swift detection of a burst


Download all Circulars as a .tar.gz archive:
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