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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.

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

3379 results found.

  1. EP250802a: Liverpool Telescope optical upper limits
  2. EP250802a: Global MASTER-Net observations report
  3. EP250802a: GROWTH-India Telescope optical upper limit
  4. EP250802a: Einstein Probe detection of an X-ray transient
  5. The EP-WXT trigger 01709198251 is likely a flaring star
  6. The EP-WXT trigger 01709198202 is likely a flaring star
  7. EP250711a: CrAO and Assy optical observations
  8. EP250730a: Global MASTER-Net observations report
  9. EP250730a: COLIBRÍ optical upper limit
  10. GRB 250727A: Swift-XRT afterglow confirmation and refined analysis
  11. EP250730a: Einstein Probe detection of an X-ray transient
  12. GRB 250727A: EP-FXT follow-up observation
  13. EP-WXT trigger 01709195487: confirmation of a stellar flare by BOOTES-6 & BOOTES-7
  14. GRB 250727A: EP-FXT counterpart detection
  15. The EP-WXT trigger 01709195487 is likely a flaring star
  16. Konus-Wind detection of GRB 250725A
  17. EP250702a/GRB250702B,D,E: SVOM/VT optical upper limit
  18. GRB 270713A: Kitab and AbAO Optical Observations
  19. Konus-Wind detection of GRB 250716A
  20. GRB 250702B,D,E / EP250702a: H.E.S.S. very-high-energy gamma-ray observations
  21. GRB 250713A: Mephisto optical upper limits
  22. GRB 250713A: SVOM/VT optical upper limit
  23. GRB 250713A: NOT optical upper limits
  24. GRB 250713A: SVOM/C-GFT upper limit
  25. GRB 250713A: Swift-XRT observations
  26. GRB 250713A: EP-FXT counterpart detection
  27. EP250711a: Global MASTER-Net observations report
  28. EP250711a: NOT optical counterpart candidate
  29. EP250711a: EP-WXT detection and FXT follow-up observation of a fast X-ray transient
  30. EP candidate (ID=08500000365): COLIBRÍ optical Upper limit
  31. GRB 250704B / EP250704a: 1.3 GHz MeerKAT Detection
  32. GRB 250702B,D,E / EP250702a: 10 GHz detection with the VLA
  33. IPN triangulation of GRB 250704B (short/hard, consistent with EP 250704a)
  34. EP/WXT 01709181970: GOTO observations confirm stellar variability
  35. EP-WXT trigger 01709181970. confirmation of a stellar flare by BOOTES-6
  36. The EP-WXT trigger 01709181970 is likely a flaring star
  37. GRB 250704B / EP250704a: VLA radio detection
  38. GRB 250706B/C: Konus-Wind analysis of the prompt emission
  39. GRB 250704B: CALET Gamma-Ray Burst Monitor detection
  40. IceCube-250706A: EP-FXT follow-up observations
  41. EP250702a/ GRB 250702B: NuSTAR X-ray Observations
  42. EP250706a/GRB 250706A: EP-WXT detection of a fast X-ray transient
  43. The EP-WXT trigger 01709181580 is likely a flaring star
  44. EP250704a / GRB 250704B: end of optical plateau phase and rapid fading of the counterpart
  45. EP250702a/GRB 250702B,C,D,E: Archival radio observations from ASKAP VAST
  46. Radio observation of GRBs 250702B,C,E / EP250702a with the Allen Telescope Array
  47. GRB 250704B: Insight-HXMT detection
  48. Konus-Wind detection of GRB 250703A
  49. EP250704a/GRB 250704B: GSP observations of the optical counterpart
  50. Konus-Wind detection of short/hard GRB 250704B/ EP250704a
  51. EP250704a / GRB 250704B: NOT observations of the optical afterglow
  52. GRB250702F: afterglow detected by joint EP-ZTF shadowing program
  53. EP250704a / GRB 250704B: VLT/X-shooter spectroscopic redshift z = 0.661
  54. EP250704a / GRB 250704B: JinShan optical observations
  55. EP250704a / GRB 250704B : GROWTH-India Telescope optical observations
  56. EP250704a / GRB 250704B: SVOM/VT optical blue counterpart
  57. EP 250704a: BOOTES-5 optical detection
  58. EP250704a: refined analysis of the EP-WXT and FXT follow-up observations
  59. GRBs 250702B/C/D/E / EP250702a: Swift/UVOT Upper Limits
  60. EP250704a / GRB250704B: Swift-XRT counterpart detection
  61. Konus-Wind detection of GRB 250702F
  62. EP250704a / GRB 250704B: VLT/FORS2 optical afterglow detection
  63. EP250704a: COLIBRÍ optical counterpart candidate
  64. EP250704a: Einstein Probe detection of an X-ray transient
  65. GRBs 250702B,C,D,E / EP250702a: SVOM/GRM observation
  66. GRB 250702B,C,D,E/EP250702a: COLIBRÍ optical upper limit
  67. EP250702a/GRB 250702B, C, D, E: EP-FXT follow-up observation
  68. EP250702a: Global MASTER-Net observations report
  69. GRB 250702B,C,D,E / EP 250702a: MAXI/GSC detection
  70. EP250702a/GRB 250702B,C,D,E: GOTO optical upper limits
  71. EP250702a : an X-ray transient detected by Einstein Probe likely associated with GRB 250702B,C,D,E
  72. Konus-Wind detection of GRB 250627A
  73. GRB 250628B: Swift-XRT observations
  74. GRB 250628B: SVOM/VT optical upper limit
  75. GRB 250628B: EP-FXT counterpart detection
  76. The EP-WXT trigger 01709179435 is likely a new outburst of the CV SS Cyg
  77. The EP-WXT trigger 01709179396 is likely a flaring star CSTAR 38580
  78. Konus-Wind detection of GRB 250620C
  79. The EP-WXT trigger 01709179071 is likely a flaring star
  80. EP-WXT trigger 01709179036: a new outburst of GRS 1739-278
  81. The EP-WXT trigger 01709178990 is likely a flaring star
  82. EP#01709178975: Swift-XRT counterpart detection
  83. EP-WXT trigger 01709178975: GOTO optical upper limit
  84. The EP-WXT trigger 01709178975 is likely a flaring star
  85. Konus-Wind detection of GRB 250615A / EP250615a
  86. Konus-Wind detection of GRB 250612C (short/hard with extended emission)
  87. EP250615a/GRB 250615A: EP-WXT detection of a fast X-ray transient
  88. EP-WXT trigger 01709178875: confirmation of a stellar flare by BOOTES-6
  89. The EP-WXT trigger 01709178875 is likely a flaring star
  90. sb25061207: Mephisto optical upper limits
  91. EP250612a / GRB 250612B: NOT optical observations of the afterglow candidate
  92. sb25061207: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  93. EP250612a: refined analysis of the EP-WXT and EP-FXT observations
  94. sb25061207: EP-FXT follow-up observation and afterglow candidate
  95. GRB 250612B: Fermi GBM Observation
  96. EP250612a / GRB 250612B: SVOM/VT optical candidate
  97. EP250612a: Global MASTER-Net observations report
  98. EP250612a/GRB 250612B: JinShan optical upper limit
  99. EP 250612a: AST3-3 Yaoan Optical Observation
  100. EP250610a: Upper limit from Fermi-GBM Observations

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