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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').

18 results found.

  1. AX J1846.4-0258: Swift-BAT refined analysis
  2. GRB 200801C: BOOTES-1 and BOOTES-2 optical limits
  3. Swift Detection of an SGR-like flare from AX J1846.4-0258
  4. Trigger 884906: Swift detection of MAXI J1631-479
  5. Trigger 878548: Swift detection of AX 1631.9-4752
  6. Swift detects a flare from AX 1631.9-4752
  7. Trigger 848584: Swift detection of AX 1631.9-4752
  8. Trigger 689353: Swift detection of a transient near Sgr A*
  9. Swift-BAT probable detection of an outburst from SGR J1819-1600 (AX J1818.8-1559)
  10. GRB 151027A: optical follow-up observations
  11. Swift trigger 649143 is not AX J1619.4-4945 or other astrophysical source
  12. Trigger 649143: Swift detection of AX J1619.4-4945
  13. Trigger 502024: Swift detection of KS 1741-293
  14. Swift detection of AX J1749.1-2639
  15. Swift-BAT Trigger #302454, correction of GCN notice, update on AX J1749.1-2639
  16. GRB 071017 - Swift XRT observations
  17. GRB 071017: a SHORT GRB detected by INTEGRAL
  18. IBAS GRB Alert # 2463: not a GRB

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