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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"

26360 results found.

  1. EP260610a: COLIBRÍ optical upper limits
  2. EP260610a: Einstein Probe detection of a fast X-ray transient
  3. Konus-Wind detection of GRB 260604C
  4. GRB 260608A: Fermi GRB Observation
  5. GRB 260604C: AstroSat CZTI detection
  6. IPN triangulation of GRB 260601B / EP260601a
  7. GRB 260604C: SVOM/ECLAIRs refined analysis
  8. GRB 260608A: SVOM/ECLAIRs refined analysis
  9. Konus-Wind detection of GRB 260607B
  10. GRB 260607B: GECAM-B observation
  11. GRB 260604C: further SAO RAS optical observations
  12. GRB 260607A / GOTO26fqf / AT2026ong: COLIBRÍ optical observations
  13. GRB 260604C: SVOM/COLIBRÍ (FM-GFT) colour evolution and confirmation of the late rebrightening
  14. GRB 260604C: SVOM/C-GFT upper limit
  15. GRB 260607B: AstroSat CZTI detection
  16. GRB 260608A: SVOM detection of a burst
  17. EP260605a: EP-FXT follow-up observation
  18. GRB 260607A: TRT optical observations
  19. GRB 260604C: GRANDMA further observations
  20. GRB 260607A: GOTO tentative optical counterpart candidate GOTO26fqf / AT2026ong
  21. GRB 260604A: SVOM/GRM detection
  22. GRB 260607B: Fermi GBM Observation
  23. GRB 260607B: Fermi-LAT detection
  24. GRB 260607B: Fermi GBM Final Localization Correction
  25. GRB 260604C: OPD1.6m - GRANDMA observations - detection
  26. GRB 260604C: GECAM-B observation
  27. GRB 260604C: 6 GHz VLA observations
  28. GRB 260604C: SAO RAS optical observations
  29. GRB 260604C: GRANDMA observations
  30. GRB 260604B: SVOM/GRM detection
  31. GRB 260605A: Insight-HXMT/HE detection
  32. GRB260603A: SVOM/ECLAIRs refined analysis
  33. EP260605a: Einstein Probe detection of a fast X-ray transient
  34. EP260603a: COLIBRÍ optical upper limit
  35. GRB 260604A: Glowbug gamma-ray detection
  36. GRB 260604C: LCO optical upper limit
  37. EP260602d: EP-FXT follow-up observation
  38. EP260602c: EP-FXT follow-up observation
  39. GRB 260601B / EP260601a: AstroSat CZTI detection
  40. GRB 260527A/EP260527a: 6 GHz VLA observations
  41. GRB 260604C: GOTO detections of the optical afterglow
  42. GRB 260604C: Kilonova-Catcher optical afterglow detection
  43. GRB 260604C: SVOM/COLIBRÍ (FM-GFT) optical observations
  44. GRB 260604C: Jinshan optical observations
  45. GRB 260604C: Fermi GBM Observation
  46. EP260602d: J-band upper limit with WINTER
  47. EP260602b: J-band upper limit with WINTER
  48. GRB 260604C: LAST detection of optical counterpart candidate
  49. SVOM GRB260604.85: Global MASTER-Net observations report
  50. GRB 260604C: SVOM detection of a long burst
  51. GRB 260515A: SVOM/VT optical detection at about 18 days post trigger
  52. GRB 260603A: NOT optical observations
  53. GRB 260601A: CALET Gamma-Ray Burst Monitor detection
  54. EP260602a: EP-FXT follow-up observation
  55. EP260603a: Einstein Probe detection of a fast X-ray transient
  56. Konus-Wind detection of GRB 260601B/EP260601a
  57. GRB 260603A: EP-FXT follow-up observation
  58. EP260601a/GRB 260601B: EP-FXT follow-up observation
  59. EP260602b: EP-FXT follow-up observation
  60. GRB 260601B/EP260601a: Glowbug gamma-ray detection
  61. GRB 260603A: Kilonova-Catcher optical upper limit
  62. GRB 260603A: SVOM/VT optical observations
  63. EP260602a: NOT NIR J-band observations
  64. GRB 260603A: SVOM/COLIBRÍ (FM-GFT) photometric redshift z = 3.57
  65. EP260602d: Einstein Probe detection of a fast X-ray transient
  66. EP260602a: SVOM/VT optical magnitudes correction
  67. GRB 260601A: SVOM/GRM observation of a short burst
  68. EP260602c: Einstein Probe detection of a fast X-ray transient
  69. GRB 260603A: SVOM/COLIBRÍ (GFT-FM) optical counterpart candidate
  70. EP260602a: COLIBRÍ optical observations
  71. SVOM GRB260603.23: Global MASTER-Net observations report
  72. GRB 260603A: SVOM detection of a burst
  73. EP260602b: Einstein Probe detection of a fast X-ray transient
  74. GRB 260601B/EP260601a: Insight-HXMT detection
  75. EP260530a: Xinglong optical spectroscopy of EP260530a / AT 2026nwl
  76. EP260602a: SVOM/VT optical candidate
  77. EP-WXT trigger 01709266414 (EP260602b): JinShan optical counterpart detection
  78. GRB 260601A: GECAM-B observation of a short burst
  79. GRB 260601B/EP260601a: J-band upper limit with WINTER
  80. EP260530a/AT 2026nwl: COLIBRÍ optical follow up
  81. GRB 260601B: CALET Gamma-Ray Burst Monitor detection
  82. GRB 260601B / EP260601a: NuSTAR detection of prompt emission
  83. EP260602a: Einstein Probe detection of a fast X-ray transient
  84. GRB 260601B/EP260601a: SVOM/VT optical observations
  85. GRB 260601B/EP260601a: GECAM-B analysis suggests a possible long duration Type I burst
  86. GRB 260601B: GECAM-B detection of a burst probably associated with EP260601a
  87. EP260601a: Einstein Probe detection of an X-ray transient
  88. EP-WXT trigger 01709266307 (EP260601a): COLIBRÍ optical observations
  89. EP-WXT trigger 01709266307 (EP260601a): JinShan optical counterpart detection
  90. GRB 260601A: Glowbug gamma-ray detection of a short burst
  91. GRB 260531B: Glowbug gamma-ray detection
  92. GRB 260601A: Fermi GBM Observation
  93. EP260530a/AT 2026nwl: COLIBRÍ optical observations
  94. GRB 260530C: SVOM/ECLAIRs detection of a burst through on-ground search
  95. GRB 260527A/EP260527a: Glowbug gamma-ray detection
  96. GRB 260531B: GECAM-B observation
  97. GRB 260518B: SVOM/ECLAIRs detection of a soft burst possibly associated with EP 260518a and AT 2026ndp
  98. GRB 260531C: Fermi GBM Final Localization Correction
  99. AT 2026nuz: COLIBRÍ optical observations
  100. IPN triangulation of GRB 260527A / EP260527a

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