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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').

13 results found.

  1. GRB 200216B: second epoch optical upper limit at Mondy observatory
  2. GRB 200216B: Mondy and AbAO optical upper limits
  3. GRB 200216B: Swift-XRT refined Analysis
  4. GRB 200216B: Swift-BAT refined analysis
  5. GRB 200216B - possible IR counterpart from VLT
  6. GRB 200216B: z-band limit from NOT
  7. GRB 200216B: Fermi GBM observation
  8. GRB 200216B: Swift/UVOT Upper Limits
  9. GRB 200216B: Enhanced Swift-XRT position
  10. GRB 200216B: Nanshan/NEXT early optical upper limit and possible host galaxy
  11. GRB 200216B: GMG upper limit
  12. GRB 200216B: Swift detection of a burst
  13. GRB 200216B: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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