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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

27283 results found.

  1. Fermi trigger No 737559855: Global MASTER-Net observations report
  2. GRB 240516A: Fermi GBM Observation
  3. GRB 240516A: GOTO optical upper limit
  4. LIGO/Virgo/KAGRA S240422ed: GRID non-detection and upper limits
  5. Fermi trigger No 737523389: Global MASTER-Net observations report
  6. GRB 240516A: Swift detection of a burst
  7. Swift GRB240516.15: Global MASTER-Net observations report
  8. Fermi trigger No 737476171: Global MASTER-Net observations report
  9. GRB 240514B: GOTO candidate optical counterpart
  10. MAXI GRB240514.78: Global MASTER-Net observations report
  11. Fermi Gamma-ray Burst Monitor list of triggers that are not a GRB
  12. GRB 240514B: Fermi GBM Detection
  13. GRB 240513A: Fermi GBM observation
  14. GRB 240514C: Fermi GBM Final Real-time Localization
  15. Fermi GRB 240514B: Global MASTER-Net observations report
  16. Fermi Gamma-ray Burst Monitor triggers 737345659/240514093 and GRB240514A are not GRBs
  17. GRB 240514B: Fermi GBM Final Real-time Localization
  18. LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
  19. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  20. LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
  21. GRB 240514A: Fermi GBM Final Real-time Localization
  22. LAT GRB240513.31: Global MASTER-Net observations report
  23. GRB 240513A: Fermi-LAT detection
  24. GRB 240511A: Fermi GBM Observation
  25. GRB 240511A: Swift-BAT refined analysis
  26. Fermi GRB 240513B: Global MASTER-Net observations report
  27. Fermi trigger No 737277727: Global MASTER-Net observations report
  28. GRB 240513B: Fermi GBM Final Real-time Localization
  29. GRB 240513A: AstroSat CZTI detection
  30. LIGO/Virgo/KAGRA S240513cx: Coverage and upper limits from MAXI/GSC observations
  31. Fermi trigger No 737258655: Global MASTER-Net observations report
  32. Fermi trigger No 737247400: Global MASTER-Net observations report
  33. Fermi trigger No 737244199: Global MASTER-Net observations report
  34. Fermi trigger No 737218721: Global MASTER-Net observations report
  35. Fermi trigger No 737196587: Global MASTER-Net observations report
  36. Fermi trigger No 737168073: Global MASTER-Net observations report
  37. GRB 240511A : MITSuME Akeno optical upper limits
  38. GRB 240511A: Swift-XRT refined Analysis
  39. GRB 240511A: optical afterglow detection from the NOT
  40. Fermi Gamma-ray Burst Monitor trigger 737102480/240511279 is not a GRB
  41. Fermi Gamma-ray Burst Monitor trigger 737111207/240511380 is not a GRB
  42. Fermi GBM trigger 737105243/240511311 is not a GRB
  43. Fermi trigger No 737173236: Global MASTER-Net observations report
  44. Fermi GRB 240511A: Global MASTER-Net observations report
  45. Swift GRB 240511A: Global MASTER-Net observations report
  46. Fermi trigger No 737105243: Global MASTER-Net observations report
  47. Fermi Gamma-ray Burst Monitor trigger 737133200/240511634 is not a GRB
  48. Fermi trigger No 737152719: Global MASTER-Net observations report
  49. GRB 240511A: Swift detection of a burst
  50. GRB 240511A: Fermi GBM Final Real-time Localization
  51. Fermi trigger No 737102480: Global MASTER-Net observations report
  52. Fermi trigger No 737111207: Global MASTER-Net observations report
  53. Fermi Gamma-ray Burst Monitor trigger 737076431/240510977 is not a GRB
  54. Fermi trigger No 736967879: Global MASTER-Net observations report
  55. EP240506a: Xinglong optical upper limit
  56. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  57. EP240506a: CrAO ZTSH optical upper limit
  58. GRB 240504A: Fermi GBM Observation
  59. Fermi Gamma-ray Burst Monitor trigger 736837160/240508208 is not a GRB
  60. EP240506a: TRT optical upper limit
  61. EP240506a: BOOTES Network optical upper limit
  62. Fermi trigger No 736733320: Global MASTER-Net observations report
  63. EP240506a: Optical upper limit with Kinder observations
  64. IPN triangulation of GRB 240504A
  65. EP240506a: EP-WXT detection of a new fast X-ray transient
  66. LIGO/Virgo/KAGRA S240422ed: Additional WINTER near-infrared J-band observations
  67. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  68. Fermi GBM triggers 736668287/240506253 and 736669277/240506265 are not GRBs
  69. Fermi trigger No 736564880: Global MASTER-Net observations report
  70. Fermi trigger No 736461232: Global MASTER-Net observations report
  71. Fermi GRB 240504A: Global MASTER-Net observations report
  72. Fermi trigger No 736472503: Global MASTER-Net observations report
  73. GRB 240504A: BALROG localization (Fermi Trigger 736492377 / GRB 240504217)
  74. GRB 240504A: Fermi GBM Final Real-time Localization
  75. Fermi trigger No 736387941: Global MASTER-Net observations report
  76. LXT 240402A / GRB 240402B: VLT X-shooter redshift of host
  77. GRB 240502A: GOTO optical upper limit
  78. Fermi trigger No 736379109: Global MASTER-Net observations report
  79. GRB 240502A: Fermi GBM Observation
  80. GRB 240502C: GOTO possible optical counterpart candidates
  81. Fermi GRB 240502B: Global MASTER-Net observations report
  82. GRB 240502C: Fermi GBM Final Localization
  83. Fermi GRB 240502A: Global MASTER-Net observations report
  84. GRB 240430A: GRBAlpha detection
  85. GRB 240502B: Fermi GBM Final Real-time Localization
  86. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet Transient Candidates
  87. Integral GRB240502.23: Global MASTER-Net observations report
  88. GRB 240502A: Fermi GBM Final Real-time Localization
  89. Fermi GRB 240501A: Global MASTER-Net observations report
  90. Fermi trigger No 736197684: Global MASTER-Net observations report
  91. GRB 240426A: VZLUSAT-2 detection
  92. GRB240430A: Fermi GBM Final Localization
  93. GRB 240501A: Fermi GBM Final Real-time Localization
  94. GRB 240408B: VZLUSAT-2 detection
  95. GRB 240407A: VZLUSAT-2 detection
  96. GRB 240429A: Fermi GBM Final Real-time Localization
  97. LIGO/Virgo/KAGRA S240422ed: GECKO/KMTNet ToO observations
  98. LIGO/Virgo/KAGRA S240429an: Retraction of GW compact binary merger candidate
  99. Fermi GRB 240428A: Global MASTER-Net observations report
  100. GRB 240428A: Fermi GBM Final Real-time Localization

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