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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 230405B: VZLUSAT-2 detection
  2. Konus-Wind detection of GRB 230405B
  3. GRB 230405B: AGILE detection
  4. GRB 230405B: Swift-XRT refined Analysis
  5. GRB 230405B: Fermi GBM Observation
  6. GRB 230405B: MeerLICHT upper limits
  7. GRB 230405B: Swift/UVOT Upper Limits
  8. GRB 230405B: AstroSat CZTI detection
  9. GRB 230405B: Enhanced Swift-XRT position
  10. Swift GRB 230405B: Global MASTER-Net observations report
  11. GRB 230405B: Prompt enhanced Swift-XRT position
  12. GRB 230405B: Swift detection of a burst
  13. GRB 230405B: Fermi GBM Final Real-time Localization


Download all Circulars as a .tar.gz archive:
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