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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"
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submitter:"Judith Racusin"

26369 results found.

  1. GRB 260601A: Fermi GBM Observation
  2. EP260530a/AT 2026nwl: COLIBRÍ optical observations
  3. GRB 260530C: SVOM/ECLAIRs detection of a burst through on-ground search
  4. GRB 260527A/EP260527a: Glowbug gamma-ray detection
  5. GRB 260531B: GECAM-B observation
  6. GRB 260518B: SVOM/ECLAIRs detection of a soft burst possibly associated with EP 260518a and AT 2026ndp
  7. GRB 260531C: Fermi GBM Final Localization Correction
  8. AT 2026nuz: COLIBRÍ optical observations
  9. IPN triangulation of GRB 260527A / EP260527a
  10. GRB 260530B: SVOM/GRM detection of a possible bright short GRB
  11. GRB 260527A / EP260527a: VLA radio detection
  12. GRB 260429B / EP260429a: COLIBRÍ optical counterpart candidate
  13. GRB 260529A: GOTO tentative optical afterglow candidate
  14. GRB 260527A/EP260527a: Insight-HXMT detection
  15. EP260526a: SVOM/VT optical upper limits
  16. GRB 260527A: CALET Gamma-Ray Burst Monitor detection
  17. EP260527a/GRB 260527A: EP-FXT follow-up observation
  18. GRB 260527A: GECAM-B detection of a short burst probably associated with EP260527a
  19. GRB 260526A: GECAM-B observation
  20. Konus-Wind detection of GRB 260527A (short/hard) ~4 min before EP260527a
  21. EP260526a: EP-FXT follow-up observation
  22. EP260527a: SVOM/VT optical observation
  23. EP260527a: COLIBRÍ optical detection
  24. EP260527a: Einstein Probe detection of a fast X-ray transient
  25. GRB 260524A: SVOM/ECLAIRs detection of a burst through on-ground search
  26. EP260526a: LCO optical upper limits
  27. EP260526a: Einstein Probe detection of a fast X-ray transient
  28. GRB 260525A: AstroSat CZTI detection
  29. EP260526.405: COLIBRÍ optical upper limits
  30. The EP-WXT trigger 01709266106 is not a real source
  31. GRB 260523B: AstroSat CZTI detection
  32. GRB 260523B: GECAM-B observation
  33. GRB 260522A: Fermi GBM Observation
  34. GRB 260522B: NuSTAR detection of prompt emission
  35. GRB 260522A: GOTO optical upper limit
  36. EP260518a: Einstein Probe detection of an sub-threshold X-ray transient with counterpart AT 2026ndp
  37. GRB 260522A: Fermi-LAT detection
  38. GRB 260519C: SVOM/GRM observation
  39. GRB 260511A: iTelescope T-75 optical detection
  40. GRB 260520B: SVOM/GRM observation
  41. GRB 260411B: TERI Gamma-ray detection
  42. GRB 260407A: TERI Gamma-ray detection
  43. GRB 260307A: TERI Gamma-ray detection
  44. GRB 260225D: TERI Gamma-ray detection
  45. GRB 251118A: TERI Gamma-ray detection
  46. GRB 251113A: TERI Gamma-ray detection
  47. GRB 260428A: TERI Gamma-ray detection
  48. Konus-Wind detection of GRB 260519C
  49. GRB 260509A: SVOM/ECLAIRs refined analysis
  50. GRB 260519D: Fermi GBM Final Localization Correction
  51. GRB 260519C: NuSTAR detection of prompt emission
  52. Konus-Wind detection of GRB 260518A
  53. GRB 260518A: AstroSat CZTI detection of a long burst
  54. GRB 260516D: SVOM/ECLAIRs refined analysis
  55. GRB 260515A: SVOM/ECLAIRs refined analysis
  56. GRB 260421B: radio detection with the VLA
  57. GRID detection of GRB 260511A
  58. GRB 260516D: EP-FXT follow-up observation
  59. GRB 260516D: GOTO optical counterpart detection
  60. GRB 260516D: LCO optical observations
  61. GRB 260515A: further Liverpool Telescope observations
  62. GRB 260516D: SVOM/COLIBRÍ (FM-GFT) optical observations
  63. GRB 260516D: GROWTH-India Telescope optical detection
  64. GRB 260516D: SVOM/VT optical bright candidate
  65. GRB 260516D: FRAM-ORM optical limit
  66. SVOM GRB260516D: Global MASTER-Net observations report
  67. GRB 260516D: SVOM possible detection of a burst
  68. Konus-Wind detection of GRB 260515A
  69. GRB 260515A: LCO optical counterpart detection
  70. GRB 260515A: SVOM/COLIBRÍ (FM-GFT) optical observations
  71. GRB 260515A: EP-FXT follow-up observation
  72. EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations
  73. EP260514a: NOT optical counterpart confirmation
  74. EP260514a: TRT optical counterpart candidate
  75. EP260514a: SVOM/VT optical candidate
  76. GRB 260515A: SVOM/VT optical observations
  77. GRB 260515A: OHP/T193 optical observations
  78. EP260514a: COLIBRÍ optical upper limits
  79. GRID detection of GRB 260507A
  80. GRB 260515A: LCO optical observations
  81. SVOM GRB 260515A: Global MASTER-Net observations report
  82. GRB 260515A: NOT optical observations.
  83. SVOM GRB 260515A: MASTER OT J151044.43+243321.7 optical counterpart detection
  84. GRB 260515A: SVOM/VT optical candidate from VHF data
  85. GRB 260515A: JinShan optical counterpart candidate
  86. GRB 260515A: SVOM detection of a burst
  87. GRB 260510C: Glowbug gamma-ray detection
  88. IceCube-260504A: No Candidate Transients from the Zwicky Transient Facility
  89. EP260514a: GROWTH-India Telescope optical upper limit
  90. GRB 260511B: NOT optical observations
  91. Konus-Wind detection of GRB 260512A
  92. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  93. EP260514a: Einstein Probe detection of a fast X-ray transient
  94. IPN triangulation of GRB 260512A
  95. GRB 260511B: Mephisto multi-band optical followup
  96. GRB 260512A: AstroSat CZTI detection
  97. EP260512a: EP-FXT follow-up observation
  98. EP260507a: Xinglong Schmidt optical counterpart detection
  99. GRB 260511B: further SAO RAS optical observations
  100. GRB 260509A: SVOM/VT optical observations

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