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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').

66 results found.

  1. GRB 230812B: Update on Bad Time Intervals for Fermi GBM data
  2. GRB 230812B: further radio observations with the VLA
  3. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  4. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  5. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  6. GRB 230812B: Radio observations with the uGMRT
  7. GRB 230812B: Bad Time Intervals for Fermi GBM data
  8. GRB 230812B: Chandra late-time detection of the X-ray afterglow
  9. GRB 230812B: Spectroscopic detection of the associated SN 2023pel.
  10. GRB 230812B: radio detection with the VLA
  11. GRB 230812B: AstroSat LAXPC detection
  12. GRB 230812B: Assy optical observations, possible SN rise
  13. GRB 230812B: SAO RAS RC-500 and Zeiss-1000 observations
  14. GRB 230812B : GRANDMA/Kilonova-Catcher optical afterglow detection and upper limits
  15. GRB 230812B: GIT Confirmation of SN rise
  16. GRB 230812B: SAO RAS Zeiss-1000 observations
  17. GRB 230812B: SAO RAS observations, possible re-brightening
  18. GRB 230812B: SAO RAS optical observations
  19. GRB 230812B: NOEMA detection
  20. GRB 230812B: optical photometry from Konkoly
  21. GRB 230812B: SAO RAS optical observations
  22. GRB 230812B: GAD Observatory optical observations (upper limit)
  23. GRB 230812B: iTelescope optical upper limit
  24. GRB 230812B: continued SAO RAS optical observation
  25. GRB 230812B: Iota Scorpii Observatory, La Spezia, Italy
  26. GRB 230812B: Tautenburg observations
  27. GRB 230812B: AMI-LA radio detection of afterglow candidate
  28. GRB 230812B: continued AbAO optical afterglow observations
  29. GRB 230812B: Optical observaions from Rozhen Observatory
  30. GRB 230812B: Further Bassano Bresciano Observatory optical observations
  31. GRB 230812B: further SAO RAS optical observations
  32. GRB 230812B: Upper limits from a neutrino search with IceCube
  33. GRB 230812B: GRANDMA further observations of ZTF23aaxeacr candidate afterglow
  34. GRB 230812B: CrAO ZTSh optical observations
  35. GRB 230812B: Koshka Zeiss-1000 optical observations
  36. GRB 230812B: GIT optical follow-up
  37. GRB 230812B: Leavitt Observatory optical observations
  38. GRB 230812B : optical observations from Observatoire de Haute-Provence
  39. GRB 230812B: Bassano Bresciano Observatory optical observations
  40. GRB 230812B: Faulkes Telescope North optical afterglow follow-up
  41. GRB 230812B: Osservatorio Astronomico "Nastro Verde" optical observation
  42. GRB 230812B: rest-frame energetics from Konus-Wind observation
  43. GRB 230812B: OASDG optical observations
  44. GRB 230812B: AbAO optical observations
  45. GRB 230812B: Spectroscopy from NOT
  46. GRB 230812B: Redshift from OSIRIS+/GTC
  47. GRB 230812B: Montarrenti Observatory optical observations
  48. GRB 230812B: SAO RAS optical observations
  49. GRB 230812B: Detected Optical Afterglow Candidate
  50. GRB 230812B: GMG - GRANDMA observations
  51. Konus-Wind detection of GRB 230812B
  52. GRB230812B: AGILE/MCAL detection
  53. GRB 230812B: GECAM-C observation of a very bright burst
  54. GRB 230812B: Swift-XRT afterglow detection
  55. GOTO confirmation and possible host galaxy of GRB230812B optical afterglow
  56. GRB 230812B: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi GRB (Trigger 713559497)
  57. Fermi GRB 230812B: MASTER optical counterpart
  58. GRB 230812B: KAIT Optical Afterglow Candidate
  59. GRB 230812B: Improved Swift/XRT localization
  60. GRB 230812B: Preliminary Swift/XRT localization
  61. GRB 230812B: Fermi-LAT detection
  62. GRB 230812B: Fermi GBM Observation of a very bright burst
  63. Fermi GRB 230812B: Global MASTER-Net observations report
  64. GRB 230812B: Tiled Swift observations
  65. GRB 230812B: Fermi GBM detection of an extremely bright GRB
  66. GRB 230812B: Fermi GBM Final Real-time Localization


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