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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"

23708 results found.

  1. IPN triangulation of GRB 240619C
  2. Fermi trigger No 741211696: Global MASTER-Net observations report
  3. EP240626a: Montarrenti Observatory optical upper limit
  4. EP240626a: KAIT optical upper limit
  5. EP240625a: GRANDMA Optical Upper Limits
  6. EP240626a: EP-FXT detection of the X-ray emission
  7. GRB 240624A: Swift-BAT refined analysis
  8. Konus-Wind detection of GRB 240619A
  9. EP240626a: BOOTES-7 optical upper limit
  10. EP240626a: EP-WXT detection of a fast X-ray transient
  11. Fermi GRB 240625B: Global MASTER-Net observations report
  12. GRB 240624B: CALET Gamma-Ray Burst Monitor detection
  13. GRB 240625A: Fermi GBM Observation
  14. EP240625a: NOT optical counterpart candidate
  15. EP240625a: EP-FXT detection of the X-ray emission
  16. GRB 240624B: GRBAlpha detection
  17. EP240625a: EP-WXT detection of a fast X-ray transient
  18. GRB240624A: Fermi GBM Observation
  19. Swift GRB 240624A: Global MASTER-Net observations report
  20. Fermi GRB 240624A: Global MASTER-Net observations report
  21. Fermi trigger No 740949590: Global MASTER-Net observations report
  22. GRB 240624A: Swift detection of a burst
  23. EP240618a: NOT further optical observations
  24. GRB 240619A: J-band detection with WINTER
  25. Fermi trigger No 740744838: Global MASTER-Net observations report
  26. EP240618a: NOT optical counterpart candidate
  27. EP240618a: GSP optical upper limit
  28. LIGO/Virgo/KAGRA S240622h: Identification of a GW compact binary merger candidate
  29. LIGO/Virgo/KAGRA S240621eb: Identification of a GW compact binary merger candidate
  30. LIGO/Virgo/KAGRA S240621dy: Identification of a GW compact binary merger candidate
  31. IPN triangulation of GRB 240615A (short)
  32. X-ray transient EP240618a: Fermi/GBM non-detection
  33. GRB 240619A: GRBAlpha detection
  34. EP240618a: Swift/XRT upper limit
  35. EP240617a: tentative Swift/XRT detection of the afterglow
  36. GRB 240619A: Swift-XRT probable afterglow detection
  37. GRB 240619A: CALET Gamma-Ray Burst Monitor detection
  38. GRB 240619A: GOTO candidate optical afterglow
  39. GRB 240615A: NOT optical observations
  40. EP240618a: GRANDMA Optical Upper Limits
  41. EP240618a: TRT optical upper limit
  42. Fermi trigger No 740474239: Global MASTER-Net observations report
  43. Fermi GRB 240619A: Global MASTER-Net observations report
  44. EP240617a: STEP/T80S optical limits
  45. LIGO/Virgo S240615dg: GRANDMA/FRAM-CTA-N Observations
  46. EP240618a: OHP/T193 MISTRAL i' and Y band upper limits
  47. EP240618a: BOOTES-6/DPRT optical upper limit
  48. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  49. Fermi trigger No 740430582: Global MASTER-Net observations report
  50. EP240617a: BOOTES-6/DPRT optical upper limit
  51. EP240617a: EP-WXT detection of a fast X-ray transient
  52. EP240618a: EP-WXT detection of a fast X-ray transient and EP-FXT quick follow-up
  53. LIGO/Virgo/KAGRA S240618ah: Identification of a GW compact binary merger candidate
  54. GRB 240615A: J-band upper limits from WINTER
  55. GRB 240615A: Swift-XRT observations
  56. Fermi trigger No 740221779: Global MASTER-Net observations report
  57. Fermi GRB 240616A: Global MASTER-Net observations report
  58. Konus-Wind detection of GRB 240615A (short/hard)
  59. GRB 240615A: GOTO optical upper limits
  60. Fermi trigger No 740166710: Global MASTER-Net observations report
  61. LIGO/Virgo/KAGRA S240615ea: Identification of a GW compact binary merger candidate
  62. LIGO/Virgo/KAGRA S240615dg: Identification of a GW compact binary merger candidate
  63. GRB 240603A: VZLUSAT-2 detection
  64. GRB 240612A: GRBAlpha detection
  65. Fermi GRB 240612B: Global MASTER-Net observations report
  66. Fermi GRB 240612A: Global MASTER-Net observations report
  67. Fermi GRB 240611A: Global MASTER-Net observations report
  68. Konus-Wind detection of GRB 240607A
  69. EXO 0748-676: Swift-BAT refined analysis
  70. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  71. GRB 240529A: LBT optical detection and late temporal decay
  72. GRB 240529A : MITSuME Akeno optical afterglow detection
  73. Trigger 1236151: Swift detection of EXO 0748-676
  74. Fermi GRB 240610A: Global MASTER-Net observations report
  75. IPN triangulation of GRB 240607A
  76. Fermi trigger No 739632045: Global MASTER-Net observations report
  77. Fermi GRB 240608A: Global MASTER-Net observations report
  78. Konus-Wind detection of GRB 240606B
  79. Fermi trigger No 739506569: Global MASTER-Net observations report
  80. Fermi GRB 240607A: Global MASTER-Net observations report
  81. GRB 240529A: NOEMA detection
  82. Fermi trigger No 739373591: Global MASTER-Net observations report
  83. GRB 240606B: Swift-XRT afterglow detection
  84. Swift GRB240606.15: Global MASTER-Net observations report
  85. Konus-Wind detection of GRB 240603A
  86. Swift Trigger 1235109: a possible GRB 240606A
  87. Fermi GRB 240604A: Global MASTER-Net observations report
  88. Fermi GRB 240605A: Global MASTER-Net observations report
  89. Fermi GRB 240605C: Global MASTER-Net observations report
  90. IPN triangulation of GRB 240603A
  91. GRB 240604A: GECAM detection of a long burst
  92. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  93. Fermi GRB 240603C: Global MASTER-Net observations report
  94. Swift Trigger 1232465: consistent with noise
  95. GRB 240529A: MASTER prompt OT detection
  96. GRB 240603A: GECAM detection of a short burst
  97. Fermi GRB 240602A: Global MASTER-Net observations report
  98. The EP-WXT source triggered on June 1st is likely a flaring star
  99. LIGO/Virgo/KAGRA S240601co: Identification of a GW compact binary merger candidate
  100. Swift Trigger 1232465 is not a GRB

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