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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"

45790 results found.

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

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