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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"

24513 results found.

  1. GRB 240619A: Swift-XRT probable afterglow detection
  2. GRB 240619A: CALET Gamma-Ray Burst Monitor detection
  3. GRB 240619C: NuSTAR automated detection of the GRB
  4. GRB 240619A: Fermi GBM Observation
  5. Fermi GBM Sub-Threshold Detection of GRB 240619C
  6. GRB 240619A: GOTO candidate optical afterglow
  7. EP240618a: Abastumani optical observationsEP240618a
  8. Fermi trigger No 740474239: Global MASTER-Net observations report
  9. Fermi GRB 240619A: Global MASTER-Net observations report
  10. LIGO/Virgo S240615dg: GRANDMA/FRAM-CTA-N Observations
  11. LIGO/Virgo/KAGRA S240615dg: Updated Sky localization
  12. LIGO/Virgo/KAGRA S240618ah: Updated Sky localization
  13. GRB 240619B: Fermi GBM Final Real-time Localization
  14. Fermi trigger No 740430582: Global MASTER-Net observations report
  15. GRB 240619A: BALROG localization (Fermi Trigger 740461416 / GRB 240619155)
  16. GRB 240619A: Fermi GBM Final Real-time Localization
  17. EP240617a is likely a GRB event
  18. EP240618a: EP-WXT detection of a fast X-ray transient and EP-FXT quick follow-up
  19. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  21. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  22. GRB 240615A: J-band upper limits from WINTER
  23. GRB 240615A: Fermi GBM Observation
  24. LIGO/Virgo/KAGRA S240615ea: Updated Sky localization
  25. GRB 240615A: Swift-XRT observations
  26. GRB 240615A: GECAM detection
  27. X-ray transient EP240414a: Chandra late time observation
  28. Fermi trigger No 740221779: Global MASTER-Net observations report
  29. Fermi GRB 240616A: Global MASTER-Net observations report
  30. Konus-Wind detection of GRB 240615A (short/hard)
  31. GRB 240615A: GOTO optical upper limits
  32. Fermi trigger No 740166710: Global MASTER-Net observations report
  33. GRB 240616A: Fermi GBM Final Real-time Localization
  34. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  35. GRB 240615A: Fermi GBM Final Real-time Localization
  36. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  37. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  38. GRB 240603A: VZLUSAT-2 detection
  39. GRB 240612A: GRBAlpha detection
  40. GRB 240613A: Fermi GBM Final Real-time Localization
  41. Fermi GRB 240612B: Global MASTER-Net observations report
  42. Fermi GRB 240612A: Global MASTER-Net observations report
  43. GRB 240612B: Fermi GBM Final Real-time Localization
  44. GRB 240612A: Fermi GBM Final Real-time Localization
  45. Fermi GRB 240611A: Global MASTER-Net observations report
  46. Konus-Wind detection of GRB 240607A
  47. GRB 240611A: Fermi GBM Final Real-time Localization
  48. EXO 0748-676: Swift-BAT refined analysis
  49. GRB 240529A: LBT optical detection and late temporal decay
  50. GRB 240529A : MITSuME Akeno optical afterglow detection
  51. Fermi GRB 240610A: Global MASTER-Net observations report
  52. GRB 240610A: Fermi GBM Final Real-time Localization
  53. IPN triangulation of GRB 240607A
  54. Fermi trigger No 739632045: Global MASTER-Net observations report
  55. Fermi GRB 240608A: Global MASTER-Net observations report
  56. Konus-Wind detection of GRB 240606B
  57. Fermi trigger No 739506569: Global MASTER-Net observations report
  58. GRB 240608A: Fermi GBM Final Real-time Localization
  59. Fermi GRB 240607A: Global MASTER-Net observations report
  60. GRB 240607A: Fermi GBM Observation
  61. GRB 240606B: Fermi GBM Observation
  62. GRB 240607A: Fermi GBM detection of a very bright burst
  63. GRB 240607A: BALROG localization (Fermi Trigger 739450879 / GRB 240607459)
  64. GRB 240607A: Fermi GBM Final Real-time Localization
  65. GRB 240606B: GECAM-B detection a long burst
  66. Fermi trigger No 739373591: Global MASTER-Net observations report
  67. Swift GRB240606.15: Global MASTER-Net observations report
  68. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  69. Konus-Wind detection of GRB 240603A
  70. Swift Trigger 1235109: a possible GRB 240606A
  71. Fermi GRB 240604A: Global MASTER-Net observations report
  72. IPN triangulation of GRB 240531A (short)
  73. Fermi GRB 240605A: Global MASTER-Net observations report
  74. Fermi GRB 240605C: Global MASTER-Net observations report
  75. LIGO/Virgo/KAGRA S240601co: Updated Sky localization
  76. GRB 240605C: Fermi GBM Final Real-time Localization
  77. IPN triangulation of GRB 240603A
  78. GRB 240605B: Fermi GBM Final Real-time Localization
  79. GRB 240604A: Fermi GBM Final Localization
  80. GRB 240605A: Fermi GBM Final Real-time Localization
  81. GRB 240604A: GECAM detection of a long burst
  82. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  83. Fermi GRB 240603C: Global MASTER-Net observations report
  84. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  85. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  86. GRB 240603A: Fermi GBM Final Localization
  87. GRB 240603C: BALROG localization (Fermi Trigger 739102156 / GRB 240603423)
  88. GRB 240603C: Fermi GBM Final Real-time Localization
  89. GRB 240603B: Swift detection of a possible burst
  90. GRB 240529A: MASTER prompt OT detection
  91. GRB 240603A: GECAM detection of a short burst
  92. Fermi GRB 240602A: Global MASTER-Net observations report
  93. The EP-WXT source triggered on June 1st is likely a flaring star
  94. LIGO/Virgo/KAGRA S240601aj: Updated Sky localization
  95. GRB 240602A: Fermi GBM Final Real-time Localization
  96. LIGO/Virgo/KAGRA S240601co: Identification of a GW compact binary merger candidate
  97. Swift Trigger 1232465 is not a GRB
  98. LIGO/Virgo/KAGRA S240530a: Updated Sky localization
  99. GRB 240529A: 1.3m DFOT Optical observations
  100. LIGO/Virgo/KAGRA S240527en: Updated Sky localization

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