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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

900 results found.

  1. MAXI GRB261012.23: Global MASTER-Net observations report
  2. GRB 261012A: MAXI GSC detection
  3. Fermi GRB 260926A: Global MASTER-Net observations report
  4. GRB 260916A: MAXI/GSC detection
  5. MAXI GRB260916.37: Global MASTER-Net observations report
  6. MAXI GRB260827.40: Global MASTER-Net observations report
  7. GRB260708B: MAXI/GSC detection
  8. GRB 260616C: GECAM-B observation of a burst
  9. GRB260616C: MAXI/GSC detection
  10. GRB 260531A: MAXI/GSC detection
  11. GRB 260510C: Glowbug gamma-ray detection
  12. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  13. GRB 260510C: Fermi GBM Observation
  14. GRB 260510C: AstroSat CZTI detection
  15. GRB 260510C: EP-FXT follow-up observation
  16. GRB 260510C: SVOM/VT optical upper limits
  17. GRB 260510C: MAXI/GSC detection
  18. GRID detection of GRB 260401A
  19. GRB 260401A: SVOM/GRM observation
  20. GRB 260401A: GECAM-B observation
  21. GRB 260401A: Fermi GBM Observation
  22. GRB 260401A: NuSTAR detection of prompt emission
  23. GRB 260401A: CALET Gamma-Ray Burst Monitor detection
  24. GRB 260401A: MAXI/GSC detection
  25. Konus-Wind detection of GRB 260226A
  26. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  27. GRB 260206A: Swift-XRT observations
  28. GRB 260206A: Tiled Swift observations
  29. GRB 260206A (or XRB from 4U 0513-40): MAXI/GSC detection
  30. GRID detection of GRB 260131A/B
  31. GRB 260131A/B: EP/FXT X-ray afterglow detection
  32. GRB 260131A: NOT spectroscopic redshift z = 1.434
  33. Konus-Wind detection of GRB 260131A/B
  34. GRB 260131A/B: GOTO candidate optical counterpart consistent with the MAXI localisation
  35. GRB 260131A/B: Fermi GBM Observation
  36. GRB 260131B: MAXI/GSC detection
  37. GRB 260120B: Swift/UVOT Detection
  38. GRB 251220A: MAXI/GSC detection
  39. GRB 251201A: GECAM-B observation of a burst
  40. GRB 251201A: SVOM/GRM observation of a burst
  41. GRB 251201A: MAXI/GSC detection
  42. SVOM GRB 251129A : MASTER optical counterpart detection
  43. Fermi GRB 251125B: Global MASTER-Net observations report
  44. GRB 251112B: MAXI/GSC detection
  45. LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
  46. GRB 251028A: Insight-HXMT/HE detection
  47. Konus-Wind detection of GRB 251028A
  48. GRB 251028A: GECAM-B detection
  49. GRB 251028A: SVOM/GRM observation
  50. GRB 251028A: Fermi GBM Observation
  51. GRB 251028A: Glowbug gamma-ray detection
  52. GRB 251028A: MAXI/GSC detection
  53. GRB 251024A: Swift-BAT refined analysis
  54. GRB 251023B: Glowbug gamma-ray detection
  55. GRB 251023B / EP#01709247298: COLIBRÍ optical counterpart candidate
  56. GRB 251023B: CALET Gamma-Ray Burst Monitor detection
  57. EP#01709247298: Swift-XRT counterpart detection
  58. GRB 251023B / MAXI J0451+122: MAXI/GSC detection
  59. GRB 250911A: MAXI/GSC detection
  60. LIGO/Virgo/KAGRA S250920bq: Coverage and upper limits from MAXI/GSC observations
  61. GRB 250830B: Swift-XRT afterglow detection
  62. LIGO/Virgo/KAGRA S250831cc: Coverage and upper limits from MAXI/GSC observations
  63. GRB 250830B: Swift-XRT observations
  64. EP250830a/GRB 250830B: Einstein Probe detection of an X-ray transient and Swift/XRT follow-up
  65. LIGO/Virgo/KAGRA S250830bp: Coverage and upper limits from MAXI/GSC observations
  66. GRB 250830B: Swift ToO observations
  67. GRB 250830B: MAXI/GSC detection
  68. GRB 250830A / MAXI J0853+337: MAXI/GSC detection
  69. LIGO/Virgo/KAGRA S250818k: Coverage and upper limits from MAXI/GSC observations
  70. GRB 250721A: Fermi GBM Observation
  71. GRB 250721A: Swift-XRT observations
  72. GRB 250721A: Tiled Swift observations
  73. GRB 250721A: MAXI/GSC detection
  74. EP250702a/GRB 250702B,C,D,E: Archival radio observations from ASKAP VAST
  75. LIGO/Virgo/KAGRA S250704ab: Coverage and upper limits from MAXI/GSC observations
  76. GRBs 250702B,C,D,E / EP250702a: SVOM/GRM observation
  77. EP250702a/GRB 250702B, C, D, E: EP-FXT follow-up observation
  78. GRBs 250702B,C,D,E / EP250702a: Konus-Wind detection of a hard X-ray transient activity
  79. GRB 250702B,C,D,E / EP 250702a: MAXI/GSC detection
  80. GRB 250625A: Swift/UVOT Upper Limits
  81. GRB 250620A: AstroSat CZTI detection
  82. GRB 250527B: Swift-XRT observations
  83. GRB 250527B: Tiled Swift observations
  84. GRB 250527B / MAXI J1450-527 : MAXI/GSC detection
  85. MAXI GRB250515.65: Global MASTER-Net observations report
  86. GRB 250507B: AstroSat CZTI detection
  87. EP#01709175213/IGR J19566+0326: Swift-XRT detection
  88. EP-WXT trigger 01709175213: a new X-ray outburst of LMXB MAXI J1957+032
  89. GRB 250331A: MAXI/GSC detection
  90. EP250311a/GRB 250311A: Correction to EP-WXT detection time
  91. EP250311a/GRB 250311A: EP-FXT follow-up observation
  92. GRB 250311A: Swift-XRT observations
  93. GRB 250311A/EP250311a: TRT optical upper limit
  94. GRB 250311A: Tiled Swift observations
  95. EP250311a/GRB 250311A: EP-WXT detection
  96. GRB 250311A/MAXI J1457-026: MAXI/GSC detection
  97. GRB 250209A: MAXI/GSC detection (possible detection of an X-ray flare from 1RXS J145110.3+310648)
  98. GRB 250207B: Swift-XRT observations
  99. GRB 250207B: Tiled Swift observations
  100. GRB 250207B: MAXI/GSC detection

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