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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').

534 results found.

  1. IceCube-250309A: MITSuME Akeno and Seimei/TriCCS optical observations
  2. GRB 250114B: Liverpool Telescope optical upper limit
  3. GRB 250114B : MITSuME Akeno optical afterglow candidate detection
  4. GRB 241030B : MITSuME Akeno optical upper limits
  5. GRB 241030A : MITSuME Akeno optical afterglow detection
  6. GRB 241002C : MITSuME Akeno optical upper limits
  7. GRB 240529A : MITSuME Akeno optical afterglow detection
  8. GRB 240511A : MITSuME Akeno optical upper limits
  9. GRB 240419B : MITSuME Akeno optical upper limits
  10. GRB 240414A : MITSuME Akeno optical upper limits
  11. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  12. GRB 240123A : MITSuME Akeno optical afterglow candidate detection
  13. GRB 231215A: Swift/UVOT Detection
  14. GRB 231215A: BOOTES-4/MET optical detection
  15. GRB 231215A: AGILE detection
  16. GRB 231215A : MITSuME Akeno optical afterglow candidate detection
  17. GRB 231205B : MITSuME Akeno optical upper limits
  18. GRB 231129A : MITSuME Akeno optical upper limits
  19. GRB 231117A : MITSuME Akeno optical afterglow candidate detection
  20. GRB 231117A: MAAO 0.7-m telescope optical upper limit
  21. GRB 231117A: afterglow candidate detection from Kinder observations with Lulin observatory
  22. GRB 231117A : MITSuME Akeno optical upper limits
  23. GRB 231115A : MITSuME Akeno and Okayama optical upper limits
  24. GRB 230805B : MITSuME Akeno optical upper limits
  25. GRB 230723B: MITSuME Ishigaki optical observation
  26. GRB 230723B: MITSuME Akeno optical afterglow candidate detection
  27. GRB 230427A: MITSuME Akeno optical upper limits
  28. GRB 230420A: MITSuME Akeno optical observation
  29. GRB 221218A: MITSuME Akeno optical upper limits
  30. GRB 221028A: GRANDMA observations
  31. GRB 221028A: MITSuME Okayama optical upper limits
  32. GRB 221009A: SARA-RM 1m Optical Afterglow Detection
  33. GRB 221009A: MITSuME Okayama optical observation
  34. GRB 2209030A: MITSuME Akeno optical upper limits
  35. GRB 220701A: MITSuME Akeno optical upper limits
  36. GRB 220527A: MITSuME Akeno continued optical observation
  37. GRB 220527A: MITSuME Akeno optical observation
  38. GRB 220521A: BOOTES-2/TELMA and CAHA 2.2m telescope optical upper limit
  39. GRB 220521A: MITSuME Akeno optical upper limits
  40. GRB 220514A: MITSuME Akeno optical observation
  41. GRB 220506A: MITSuME Akeno optical upper limits
  42. GRB 220412A: GRANDMA observations
  43. GRB 220412A: BOOTES-network optical upper limits
  44. GRB 220412B: BOOTES-1 optical upper limit
  45. GRB 220412A: MITSuME Akeno optical upper limits
  46. GRB 220412B: MITSuME Akeno optical upper limits
  47. GRB 220319A: MITSuME Akeno optical upper limits
  48. GRB 220310A: MITSuME Akeno optical observation
  49. GRB 220311A: MITSuME Akeno optical upper limits
  50. GRB 220118A: MITSuME Akeno optical observation
  51. GRB 220117A: MITSuME Akeno optical upper limits
  52. GRB 220117B: MITSuME Akeno optical upper limits
  53. GRB 220107B: MITSuME Akeno optical upper limits
  54. GRB 220107A: MITSuME Akeno optical observation
  55. GRB 211225A: MITSuME Akeno optical upper limits
  56. GRB 211218A: MITSuME Akeno optical upper limits
  57. GRB 211211A: MITSuME Akeno optical observation
  58. GRB 211129A: MITSuME Akeno optical upper limits
  59. GRB 211024A: MITSuME Akeno optical observation
  60. GRB 211023B: MITSuME Akeno optical upper limits
  61. Swift trigger 1078701: MITSuME Akeno optical upper limits
  62. IceCube-20210922A: No optical counterparts found by MITSuME observations
  63. GRB 210919A: MITSuME Akeno optical upper limits
  64. GRB 210824A: MITSuME Akeno optical upper limits
  65. GRB 210802A: MITSuME Okayama optical upper limits
  66. GRB 210725A: MITSuME Akeno optical upper limits
  67. GRB 210610B: MITSuME Akeno optical observation
  68. GRB 210610A: 1.5m OSN optical observation
  69. GRB 210610A: MITSuME Ishigaki optical observation
  70. GRB 210610A: MITSuME Akeno optical observation
  71. GRB 210528B: MITSuME Akeno optical upper limits
  72. GRB 210527A: MITSuME Akeno optical upper limits
  73. GRB 210504A: MITSuME Akeno optical upper limits
  74. GRB 210424B: MITSuME Akeno optical upper limits
  75. GRB 210421A: MITSuME Akeno optical upper limits
  76. GRB 210413B: MITSuME Okayama optical upper limits
  77. GRB 210419C: MITSuME Akeno optical upper limits
  78. GRB 210410A: MITSuME Akeno optical upper limits
  79. GRB 210318B: MITSuME Okayama optical upper limits
  80. GRB 210308A: MITSuME Okayama optical upper limits
  81. GRB 210306A: MITSuME Akeno optical observation
  82. GRB 210222B: MITSuME Akeno optical upper limits
  83. GRB 210218A: MITSuME Akeno optical upper limits
  84. GRB 210212A: MITSuME Akeno optical upper limits
  85. GRB 210209A: BOOTES-4/MET optical upper limit
  86. GRB 210209A: MITSuME Akeno optical upper limits
  87. GRB 210205A: MITSuME Ishigaki optical observation
  88. GRB 210104A: MITSuME Ishigaki optical observation
  89. GRB 210104A: MITSuME Akeno optical observation
  90. GRB 201223A: MITSuME Akeno optical observation
  91. GRB 201214B: MITSuME Akeno optical upper limits
  92. GRB 201203A: MITSuME Okayama optical upper limits
  93. GRB 201104B: MITSuME Akeno optical observation
  94. GRB 201027A: MITSuME Akeno optical upper limits
  95. GRB 201024A: MITSuME Akeno optical upper limits
  96. GRB 201020A: MITSuME Akeno optical observation
  97. GRB 201017A: MITSuME Akeno optical upper limits
  98. GRB 201006A: MITSuME Akeno optical upper limits
  99. GRB 201001A: MITSuME Akeno optical upper limits
  100. GRB 200907B: AstroSat CZTI detection

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