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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"

40 results found.

  1. EP260213a: NUTTelA-TAO Early Optical Limits
  2. GRB 251222A: NUTTelA-TAO Early Measurements
  3. GRB 251126A NUTTelA-TAO Early Measurements
  4. GRB 251013C NUTTelA-TAO / BSTI Early Measurements
  5. GRB 250617B: Kilonova-Catcher optical afterglow detection
  6. GRB 250617B: NUTTelA-TAO early time optical observations
  7. GRB 250430A: NUTTelA-TAO Early Measurements
  8. GRB 250402A: NUTTelA-TAO Early Optical Limits
  9. EP250302a: NUTTelA-TAO Early Measurments
  10. GRB 250219A: NUTTelA-TAO / BSTI Optical Limits
  11. GRB 250101A: NUTTelA-TAO / BSTI Optical Limits
  12. GRB 250101A NUTTelA-TAO / BSTI Early Measurements
  13. GRB 241229B: NUTTelA-TAO / BSTI Optical Limits
  14. GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
  15. EP241101a NUTTelA-TAO / BSTI Measurements 2024-11-02
  16. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits (duplicate submission of 38023)
  17. GRB 241030B: NUTTelA-TAO / BSTI Optical Limits
  18. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  19. GRB 240825A: NUTTelA-TAO / BSTI Optical Limits
  20. GRB 240805B: NUTTelA-TAO / BSTI Optical Limits
  21. GRB 231205B: NUTTelA-TAO / BSTI Early Optical Limits
  22. GRB231111A: MDM 2.4m Hiltner Telescope Observation
  23. GRB 231111A NUTTelA-TAO / BSTI Early Measurements
  24. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  25. GRB 230328B NUTTelA-TAO / BSTI Early Measurements
  26. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  27. GRB 221028A: GRANDMA observations
  28. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  29. GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
  30. GRB 220711B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  31. GRB 220403B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  32. GRB 220118A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  33. GRB 211221A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  34. GRB 211023B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  35. GRB 210820A: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
  36. GRB 201015A NUTTelA-TAO / BSTI Early Measurements (Preliminary)
  37. GRB 200925B NUTTelA-TAO / BSTI Early Measurements (Preliminary)
  38. LIGO/Virgo S190728q: ZTF19abjethn TShAO and NUTTelA-TAO optical observations / classification
  39. GRB 190627A: NUTTelA-TAO optical counterpart observations
  40. GRB 190627A: NUTTelA-TAO optical observations

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