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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"

19605 results found.

  1. EP240703c: Kinder optical follow-up and Swift XRT observations
  2. EP240703c: EP-WXT detection of an X-ray transient
  3. IPN triangulation of GRB 240627A
  4. EP240703b: EP-WXT detection of a fast X-ray transient
  5. EP240702a: Swift/XRT upper limit
  6. EP240703a: EP-WXT detection of a fast X-ray transient
  7. EP240702a: EP-WXT detection of a fast X-ray transient
  8. LIGO/Virgo/KAGRA S240627by: Upper limits from Swift/BAT-GUANO
  9. IPN triangulation of GRB 240619C
  10. GRB 240624A: Swift-BAT refined analysis
  11. Konus-Wind detection of GRB 240619A
  12. GRB240624A: Fermi GBM Observation
  13. LIGO/Virgo/KAGRA S240622h: Upper limits from Swift/BAT-GUANO
  14. LIGO/Virgo/KAGRA S240621dy: Upper limits from Swift/BAT-GUANO
  15. LIGO/Virgo/KAGRA S240618ah: Upper limits from Swift/BAT-GUANO
  16. Swift GRB 240624A: Global MASTER-Net observations report
  17. GRB 240624A: Swift detection of a burst
  18. GRB 240529A: JinShan optical observations
  19. IPN triangulation of GRB 240615A (short)
  20. EP240618a: Swift/XRT upper limit
  21. EP240617a: tentative Swift/XRT detection of the afterglow
  22. GRB 240619A: Swift-XRT probable afterglow detection
  23. GRB 240619A: Swift ToO observations
  24. GRB 240615A: NOT optical observations
  25. GRB 240615A: possible transient detection from Wendelstein observations
  26. LIGO/Virgo S240615dg: Swift XRT observations, 39 X-ray sources
  27. GRB240615A: 1.3m DFOT optical upper limit
  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. GRB 240615A: Swift-XRT observations
  33. GRB 240615A: GECAM detection
  34. GRB 240615A: FLWO-1.2m optical upper limits
  35. Konus-Wind detection of GRB 240615A (short/hard)
  36. GRB 240615A: GOTO optical upper limits
  37. GRB 240615A: Swift ToO observations
  38. GRB 240615A: Swift/BAT-GUANO arcminute localization of a short burst
  39. EXO 0748-676: Swift-BAT refined analysis
  40. GRB240529A: 3.6m TNG NIR detection 8d after the burst
  41. GRB 240529A: LBT optical detection and late temporal decay
  42. GRB 240529A : MITSuME Akeno optical afterglow detection
  43. Trigger 1236151: Swift detection of EXO 0748-676
  44. IPN triangulation of GRB 240607A
  45. Konus-Wind detection of GRB 240606B
  46. GRB 240606B: Fermi GBM Observation
  47. Swift Trigger 1235109: consistent with noise and not astrophysical
  48. GRB 240606B: GECAM-B detection a long burst
  49. GRB 240606B: Swift-XRT afterglow detection
  50. Swift GRB240606.15: Global MASTER-Net observations report
  51. GRB 240606B: Swift ToO observations
  52. GRB 240606B: Swift/BAT-GUANO arcminute localization of a burst
  53. Swift Trigger 1235109: a possible GRB 240606A
  54. IPN triangulation of GRB 240531A (short)
  55. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  56. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  57. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  58. Swift Trigger 1232465: consistent with noise
  59. GRB 240603B: Swift detection of a possible burst
  60. GRB 240529A: MASTER prompt OT detection
  61. GRB 240529A: OSN optical detection
  62. Swift Trigger 1232465 is not a GRB
  63. GRB 240529A: 1.3m DFOT Optical observations
  64. Konus-Wind detection of GRB 240529A
  65. IPN triangulation of the initial episode of GRB 240529A
  66. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  67. GRB 240529A: Insight-HXMT/HE detection
  68. GRB 240529A: GROWTH-India optical follow-up
  69. LIGO/Virgo/KAGRA S240527fv: Upper limits from Swift/BAT-GUANO
  70. LIGO/Virgo/KAGRA S240525p: Upper limits from Swift/BAT-GUANO
  71. GRB 240529A: Skynet Optical Observations
  72. GRB 240529A: Swift-BAT refined analysis
  73. GRB 240529A: Swift-XRT refined Analysis
  74. GRB240529A: BOOTES-6/DPRT optical detection
  75. GRB 240529A: Swift/UVOT Detection
  76. GRB 240529A: NOT optical observations
  77. GRB 240529A: AstroSat CZTI detection
  78. GRB 240529A: GOTO optical afterglow detection
  79. GRB 240527B: Swift-XRT afterglow detection
  80. GRB 240529A: Enhanced Swift-XRT position
  81. GRB 240529A: Swift detection of a burst with an optical counterpart
  82. Swift GRB240529.12: Global MASTER-Net observations report
  83. GRB 240527B: Fermi-LAT detection
  84. GRB 240523A: Swift-BAT refined analysis
  85. GRB 240523A: Swift-XRT refined Analysis
  86. GRB 240523A: Enhanced Swift-XRT position
  87. GRB 240523A: Swift detection of a burst
  88. GRB 240521B: Fermi GBM Observation
  89. GRB 240513A: Swift-XRT afterglow detection
  90. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  91. LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
  92. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  93. LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
  94. GRB 240504A: VZLUSAT-2 detection
  95. GRB 240516A: Swift/UVOT Upper Limits
  96. GRB 240516A: Swift-BAT refined analysis
  97. GRB 240516A ATCA radio observations
  98. IPN triangulation of GRB 240514B (short)
  99. GRB 240513A: Swift ToO observations
  100. GRB 240516A: AstroSat CZTI detection

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