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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

33 results found.

  1. GRB 201015A: evidence of supernova in LBT spectra
  2. GRB 201015A: optical observations and supernova identification
  3. GRB 201015A: 5-GHz radio afterglow detection with the EVN
  4. GRB 201015A L-band observations with e-MERLIN
  5. GRB 201015A radio afterglow with e-MERLIN
  6. GRB 201015A: Swift-XRT late time observations
  7. GRB 201015A: Late X-ray Detections with Chandra
  8. GRB 201015A: SAO RAS optical observations
  9. GRB 201015A: 6 GHz VLA radio afterglow candidate detection
  10. GRB 201015A: GROWTH-India Telescope (GIT) upper limit
  11. GRB 201015A: HCT optical photometric follow-up
  12. GRB 201015A: Xinglong-2.16m optical observations
  13. GRB 201015A: MMT afterglow imaging
  14. GRB 201015A NUTTelA-TAO / BSTI Early Measurements (Preliminary)
  15. GRB 201015A: Assy and Mondy optical observations
  16. GRB 201015A: classification as long GRB
  17. GRB 201015A: FRAM-ORM afterglow detection
  18. Fermi GBM Sub-Threshold Detection of GRB 201015A
  19. GRB 201015A: Swift/UVOT Detection
  20. GRB 201015A: redshift confirmation
  21. GRB 201015A: Swift-XRT refined Analysis
  22. MAGIC observations of GRB 201015A: hint of very high energy gamma-ray signal
  23. GRB 201015A: Swift-BAT refined analysis (a soft short pulse with a tail emission)
  24. GRB 201015A: CrAO/ZTSH optical observations
  25. GRB201015A: Nanshan/NEXT early optical observations
  26. GRB 201015A: Redshift from GTC/OSIRIS
  27. GRB 201015A: Enhanced Swift-XRT position
  28. GRB 201015A: BOOTES-1 early optical afterglow detection
  29. GRB 201015A: GOTO confirmation of afterglow detection
  30. GRB 201015A: NOT optical afterglow confirmation
  31. GRB 201015A: Swift-XRT observations
  32. Swift GRB 201015A: Global MASTER-Net observations report
  33. GRB 201015A: Swift detection of a burst

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