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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"

58 results found.

  1. GRB 250502A: Bassano Bresciano Observatory upper limit
  2. GRB 250430A: Bassano Bresciano Observatory upper limit
  3. GRB20250327B: 45th Parallel Observatory upper limit
  4. GRB 250103A: Bassano Bresciano Observatory upper limit
  5. GRB 240727A: VIRT Optical Upper Limit
  6. Fermi GRB 240828A: Bassano Bresciano Observatory upper limit
  7. GRB 240811A: Bassano Bresciano Observatory upper limit
  8. GRB 240809A: Bassano Bresciano Observatory optical observations
  9. GRB 240805B Bassano Bresciano Observatory upper limit
  10. EP240802A: Bassano Bresciano Observatory upper limit
  11. GRB 240727A: Correction to time in GCN36960
  12. GRB 240727A Bassano Bresciano Observatory upper limit
  13. Swift J1727.8-1613 (GRB 230824A): Bassano Bresciano Observatory optical observations
  14. GRB 230818A: Bassano Bresciano Observatory optical observations
  15. GRB 230812B: Further Bassano Bresciano Observatory optical observations
  16. GRB 230812B: Bassano Bresciano Observatory optical observations
  17. GRB 230805B: Bassano Bresciano observatory upper limit
  18. GRB 230723B: Bassano Bresciano Observatory upper limit
  19. GRB 230427A: GIT optical upper limit
  20. GRB 230427A: Bassano Bresciano Observatory upper limit
  21. GRB 230414B: Bassano Bresciano Observatory optical observations
  22. GRB 190106A: Swift/UVOT Detection
  23. GRB 190106A: Bassano Bresciano Observatory optical detection
  24. GRB 190103B: Bassano Bresciano observatory upper limit
  25. GRB 161004A: Bassano Bresciano Observatory upper limit
  26. GRB 160927A: Bassano Bresciano Observatory optical upper limit
  27. GRB 160925A: Bassano Bresciano Photometry of MASTER optical transient
  28. GRB 160824A: Bassano Bresciano Observatory upper limits
  29. GRB 160703A: Bassano Bresciano Observatory upper limits
  30. GRB 160504A: Bassano Bresciano Observatory upper limits
  31. GRB 160131A: Bassano Bresciano Observatory optical observations
  32. GRB 150413A: RTT150 optical observations
  33. GRB 150413A: Bassano Bresciano Observatory optical observations
  34. GRB 141031B: Bassano Bresciano Observatory upper limit
  35. GRB 140311A: Bassano Bresciano Observatory optical upper limit
  36. GRB 140206A: Bassano Bresciano Observatory optical upper limit
  37. GRB 131127B: Bassano Bresciano Observatory,archival confirmation of iPTF13ecv
  38. GRB 131202A: Bassano Bresciano Observatory optical upper limit
  39. GRB 131127B: Bassano Bresciano Observatory optical observations of iPTF13ecv
  40. GRB 131128A: Bassano Bresciano Observatory optical upper limit
  41. GRB 131127B: Bassano Bresciano Observatory optical observations
  42. GRB 131127A: Bassano Bresciano Observatory optical upper limit
  43. GRB 131030A: Bassano Bresciano Observatory optical observations
  44. GRB 130513A: Bassano Bresciano optical upper limit
  45. GRB 130504A: Bassano Bresciano Observatory optical upper limit
  46. GRB 130418A: Bassano Bresciano Observatory lightcurve analisis
  47. GRB 130418A: Bassano Bresciano Observatory optical observations
  48. GRB 120819A: Bassano Bresciano Observatory optical observations
  49. GRB 120816A: Bassano Bresciano Observatory optical observations
  50. GRB 120811C: Bassano Bresciano Observatory optical observations
  51. GRB 120326A: Bassano Bresciano Observatory - correction for GCN Cir 13178
  52. GRB 120326A: Cima Rest and Bassano Brescia
  53. GRB 120326A: Bassano Bresciano Observatory lightcurve analisis
  54. GRB 120326A: Bassano Bresciano Observatory optical observations
  55. GRB 120326A: Bassano Bresciano Observatory further optical observations
  56. GRB 120326A: Bassano Bresciano Observatory optical observations
  57. GRB 120116A: Bassano Bresciano Observatory optical observations
  58. GRB 120106A: Bassano Bresciano Observatory optical observations

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