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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

18308 results found.

  1. LIGO/Virgo S240615dg: Swift XRT observations, 28 futher X-ray sources
  2. IPN triangulation of GRB 240628B (short)
  3. EP240703a and EP240703b: Swift/XRT upper limits
  4. EP240703c: Kinder optical follow-up and Swift XRT observations
  5. EP240703c: EP-WXT detection of an X-ray transient
  6. IPN triangulation of GRB 240627A
  7. EP240703b: EP-WXT detection of a fast X-ray transient
  8. EP240702a: Swift/XRT upper limit
  9. EP240703a: EP-WXT detection of a fast X-ray transient
  10. EP240702a: EP-WXT detection of a fast X-ray transient
  11. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  12. IPN triangulation of GRB 240619C
  13. GRB 240624A: Swift-BAT refined analysis
  14. Konus-Wind detection of GRB 240619A
  15. GRB240624A: Fermi GBM Observation
  16. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  17. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  18. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  19. Swift GRB 240624A: Global MASTER-Net observations report
  20. GRB 240624A: Swift detection of a burst
  21. GRB 240529A: JinShan optical observations
  22. IPN triangulation of GRB 240615A (short)
  23. EP240618a: Swift/XRT upper limit
  24. EP240617a: tentative Swift/XRT detection of the afterglow
  25. GRB 240619A: Swift-XRT probable afterglow detection
  26. GRB 240619A: Swift ToO observations
  27. GRB 240615A: NOT optical observations
  28. GRB 240615A: possible transient detection from Wendelstein observations
  29. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  30. GRB240615A: 1.3m DFOT optical upper limit
  31. LIGO/Virgo/KAGRA S240615ea: Upper limits from Swift/BAT-GUANO
  32. LIGO/Virgo/KAGRA S240615dg: Upper limits from Swift/BAT-GUANO
  33. GRB 240615A: J-band upper limits from WINTER
  34. GRB 240615A: Fermi GBM Observation
  35. GRB 240615A: Swift-XRT observations
  36. GRB 240615A: GECAM detection
  37. GRB 240615A: FLWO-1.2m optical upper limits
  38. Konus-Wind detection of GRB 240615A (short/hard)
  39. GRB 240615A: GOTO optical upper limits
  40. GRB 240615A: Swift ToO observations
  41. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  42. EXO 0748-676: Swift-BAT refined analysis
  43. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  44. GRB 240529A: LBT optical detection and late temporal decay
  45. GRB 240529A : MITSuME Akeno optical afterglow detection
  46. Trigger 1236151: Swift detection of EXO 0748-676
  47. IPN triangulation of GRB 240607A
  48. Konus-Wind detection of GRB 240606B
  49. GRB 240606B: Fermi GBM Observation
  50. Swift Trigger 1235109: consistent with noise and not astrophysical
  51. GRB 240606B: GECAM-B detection a long burst
  52. GRB 240606B: Swift-XRT afterglow detection
  53. Swift GRB240606.15: Global MASTER-Net observations report
  54. GRB 240606B: Swift ToO observations
  55. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  56. Swift Trigger 1235109: a possible GRB 240606A
  57. IPN triangulation of GRB 240531A (short)
  58. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  59. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  60. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  61. Swift Trigger 1232465: consistent with noise
  62. GRB 240603B: Swift detection of a possible burst
  63. GRB 240529A: MASTER prompt OT detection
  64. GRB 240529A: OSN optical detection
  65. Swift Trigger 1232465 is not a GRB
  66. GRB 240529A: 1.3m DFOT Optical observations
  67. Konus-Wind detection of GRB 240529A
  68. IPN triangulation of the initial episode of GRB 240529A
  69. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  70. GRB 240529A: Insight-HXMT/HE detection
  71. GRB 240529A: GROWTH-India optical follow-up
  72. LIGO/Virgo/KAGRA S240527fv: Upper limits from Swift/BAT-GUANO
  73. LIGO/Virgo/KAGRA S240525p: Upper limits from Swift/BAT-GUANO
  74. GRB 240529A: Skynet Optical Observations
  75. GRB 240529A: Swift-BAT refined analysis
  76. GRB 240529A: Swift-XRT refined Analysis
  77. GRB240529A: BOOTES-6/DPRT optical detection
  78. GRB 240529A: Swift/UVOT Detection
  79. GRB 240529A: NOT optical observations
  80. GRB 240529A: AstroSat CZTI detection
  81. GRB 240529A: GOTO optical afterglow detection
  82. GRB 240527B: Swift-XRT afterglow detection
  83. GRB 240529A: Enhanced Swift-XRT position
  84. GRB 240529A: Swift detection of a burst with an optical counterpart
  85. Swift GRB240529.12: Global MASTER-Net observations report
  86. GRB 240527B: Fermi-LAT detection
  87. GRB 240523A: Swift-BAT refined analysis
  88. GRB 240523A: Swift-XRT refined Analysis
  89. GRB 240523A: Enhanced Swift-XRT position
  90. GRB 240523A: Swift detection of a burst
  91. GRB 240521B: Fermi GBM Observation
  92. GRB 240513A: Swift-XRT afterglow detection
  93. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  94. LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
  95. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  96. LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
  97. GRB 240504A: VZLUSAT-2 detection
  98. GRB 240516A: Swift/UVOT Upper Limits
  99. GRB 240516A: Swift-BAT refined analysis
  100. GRB 240516A ATCA radio observations

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