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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"

45791 results found.

  1. Fermi GBM Sub-Threshold Detection of GRB 240619C
  2. GRB 240619A: GOTO candidate optical afterglow
  3. EP240618a: Abastumani optical observationsEP240618a
  4. GRB 240615A: NOT optical observations
  5. EP240618a: GRANDMA Optical Upper Limits
  6. GRB 240619C: AstroSat CZTI detection
  7. EP240618a: TRT optical upper limit
  8. Fermi trigger No 740474239: Global MASTER-Net observations report
  9. Fermi GRB 240619A: Global MASTER-Net observations report
  10. EP240617a: STEP/T80S optical limits
  11. GRB 240615A: possible transient detection from Wendelstein observations
  12. LIGO/Virgo S240615dg: GRANDMA/FRAM-CTA-N Observations
  13. LIGO/Virgo/KAGRA S240615dg: Updated Sky localization
  14. LIGO/Virgo/KAGRA S240618ah: Updated Sky localization
  15. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  16. EP240618a: BOOTES-6/DPRT optical upper limit
  17. Fermi Gamma-ray Burst Monitor trigger 740474239/240619304 is not a GRB
  18. GRB 240619B: Fermi GBM Final Real-time Localization
  19. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  20. Fermi trigger No 740430582: Global MASTER-Net observations report
  21. GRB240615A: 1.3m DFOT optical upper limit
  22. GRB 240619A: BALROG localization (Fermi Trigger 740461416 / GRB 240619155)
  23. GRB 240619A: Fermi GBM Final Real-time Localization
  24. EP240617a: BOOTES-6/DPRT optical upper limit
  25. EP240617a is likely a GRB event
  26. EP240617a: EP-WXT detection of a fast X-ray transient
  27. EP240618a: EP-WXT detection of a fast X-ray transient and EP-FXT quick follow-up
  28. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  30. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  31. GRB 240615A: J-band upper limits from WINTER
  32. GRB 240615A: Fermi GBM Observation
  33. LIGO/Virgo/KAGRA S240615ea: Updated Sky localization
  34. GRB 240615A: Swift-XRT observations
  35. GRB 240615A: GECAM detection
  36. X-ray transient EP240414a: Chandra late time observation
  37. GRB 240615A: FLWO-1.2m optical upper limits
  38. Fermi trigger No 740221779: Global MASTER-Net observations report
  39. Fermi GRB 240616A: Global MASTER-Net observations report
  40. Konus-Wind detection of GRB 240615A (short/hard)
  41. GRB 240615A: GOTO optical upper limits
  42. Fermi trigger No 740166710: Global MASTER-Net observations report
  43. GRB 240616A: Fermi GBM Final Real-time Localization
  44. GRB 240615A: Swift ToO observations
  45. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  46. GRB 240615A: Fermi GBM Final Real-time Localization
  47. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  48. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  49. GRB 240603A: VZLUSAT-2 detection
  50. GRB 240612A: GRBAlpha detection
  51. GRB 240613A: Fermi GBM Final Real-time Localization
  52. Fermi GRB 240612B: Global MASTER-Net observations report
  53. Fermi GRB 240612A: Global MASTER-Net observations report
  54. GRB 240612B: Fermi GBM Final Real-time Localization
  55. GRB 240612A: Fermi GBM Final Real-time Localization
  56. GRB 240607A: GECAM detection of a bright long burst
  57. Fermi GRB 240611A: Global MASTER-Net observations report
  58. Konus-Wind detection of GRB 240607A
  59. GRB 240611A: Fermi GBM Final Real-time Localization
  60. EXO 0748-676: Swift-BAT refined analysis
  61. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  62. GRB 240529A: LBT optical detection and late temporal decay
  63. GRB 240529A : MITSuME Akeno optical afterglow detection
  64. Trigger 1236151: Swift detection of EXO 0748-676
  65. Fermi GRB 240610A: Global MASTER-Net observations report
  66. GRB 240610A: Fermi GBM Final Real-time Localization
  67. IPN triangulation of GRB 240607A
  68. Fermi Gamma-ray Burst Monitor trigger 739632045/240609556 is not a GRB
  69. Fermi trigger No 739632045: Global MASTER-Net observations report
  70. Fermi GRB 240608A: Global MASTER-Net observations report
  71. Konus-Wind detection of GRB 240606B
  72. Fermi trigger No 739506569: Global MASTER-Net observations report
  73. GRB 240608A: Fermi GBM Final Real-time Localization
  74. Fermi GRB 240607A: Global MASTER-Net observations report
  75. GRB 240529A: NOEMA detection
  76. GRB 240607A: Fermi GBM Observation
  77. GRB 240606B: Fermi GBM Observation
  78. Swift Trigger 1235109: consistent with noise and not astrophysical
  79. GRB 240607A: AstroSat CZTI detection of bright long burst
  80. GRB 240607A: Fermi GBM detection of a very bright burst
  81. GRB 240529A: radio detection with AMI-LA
  82. GRB 240607A: BALROG localization (Fermi Trigger 739450879 / GRB 240607459)
  83. GRB 240607A: Fermi GBM Final Real-time Localization
  84. GRB 240606B: GECAM-B detection a long burst
  85. Fermi trigger No 739373591: Global MASTER-Net observations report
  86. GRB 240606B: Swift-XRT afterglow detection
  87. Swift GRB240606.15: Global MASTER-Net observations report
  88. GRB 240606B: Swift ToO observations
  89. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  90. Konus-Wind detection of GRB 240603A
  91. Swift Trigger 1235109: a possible GRB 240606A
  92. Fermi GRB 240604A: Global MASTER-Net observations report
  93. IPN triangulation of GRB 240531A (short)
  94. Fermi GRB 240605A: Global MASTER-Net observations report
  95. Fermi GRB 240605C: Global MASTER-Net observations report
  96. Fermi Gamma-ray Burst Monitor trigger 739290883/240605607 is not a GRB
  97. LIGO/Virgo/KAGRA S240601co: Updated Sky localization
  98. GRB 240605C: Fermi GBM Final Real-time Localization
  99. IPN triangulation of GRB 240603A
  100. GRB 240605B: Fermi GBM Final Real-time Localization

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