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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').

39 results found.

  1. EP250404a / GRB 250404A: Montarrenti Observatory optical observations
  2. GRB 250403A: Montarrenti Observatory optical detection
  3. EP250302a: Montarrenti Observatory optical detection
  4. GRB 250129A: GRANDMA Continued Afterglow Detection
  5. GRB 250103A: Montarrenti Observatory optical detection
  6. GRB 250101A: Montarrenti Observatory optical observations and rebrightening
  7. GRB 241215A: Montarrenti Observatory optical upper limit
  8. GRB 241030B: Montarrenti Observatory optical upper limit
  9. GRB 240825A: Montarrenti Observatory optical follow-up observations
  10. GRB 240825A: Montarrenti Observatory optical observations
  11. SGR 1E 1841-045 / Kes 73: Montarrenti Observatory optical upper limits
  12. EP240802a: Montarrenti Observatory optical upper limit
  13. EP240801a: GRANDMA and Kilonova-Catcher optical observations
  14. EP240626a: Montarrenti Observatory optical upper limit
  15. IceCube-240327B: GRANDMA/Kilonova-Catcher observations of 4FGL J0555.9+0030 and optical upper limits
  16. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  17. GRB240204A: VIRT optical upper limit
  18. GRB 240204A: Montarrenti Observatory optical observations
  19. Swift J1727.8-1613 (GRB 230824A): Montarrenti Observatory photometric observations
  20. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  21. GRB 230812B: Montarrenti Observatory optical observations
  22. GRB 230723B: Montarrenti Observatory upper limit
  23. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  24. GRB 230414B: Montarrenti Observatory late time optical afterglow detection
  25. GRB221120A: Montarrenti Observatory Upper Limit
  26. GRB 221009A: GRANDMA/Kilonova-Catcher observations
  27. GRB 210610B: University of Siena Observatory optical photometry of the afterglow
  28. GRB 210420B: Montarrenti Observatory follow-up observations
  29. GRB 210420B: Montarrenti Observatory optical afterglow detection
  30. GRB 210419C: Montarrenti Observatory Upper Limit
  31. GRB 210402A: BOOTES-network early optical upper limit
  32. GRB 210402A: Montarrenti Observatory upper limit
  33. GRB 190627A: Montarrenti Observatory optical detection
  34. GRB 140311A: Montarrenti Observatory optical upper limit
  35. GRB 130831A: Montarrenti Observatory optical follow-up
  36. GRB 130831A: Montarrenti Observatory optical observations
  37. GRB130606A: Montarrenti Observatory afterglow detection
  38. GRB 120311A: C88 optical limits
  39. GRB 120311B: C88 optical limits

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