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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"

26533 results found.

  1. GRB 260522A: Fermi-LAT detection
  2. GRB 260519C: SVOM/GRM observation
  3. GRB 260511A: iTelescope T-75 optical detection
  4. GRB 260520B: SVOM/GRM observation
  5. GRB 260411B: TERI Gamma-ray detection
  6. GRB 260407A: TERI Gamma-ray detection
  7. GRB 260307A: TERI Gamma-ray detection
  8. GRB 260225D: TERI Gamma-ray detection
  9. GRB 251118A: TERI Gamma-ray detection
  10. GRB 251113A: TERI Gamma-ray detection
  11. GRB 260428A: TERI Gamma-ray detection
  12. Konus-Wind detection of GRB 260519C
  13. GRB 260509A: SVOM/ECLAIRs refined analysis
  14. GRB 260519D: Fermi GBM Final Localization Correction
  15. GRB 260519C: NuSTAR detection of prompt emission
  16. Konus-Wind detection of GRB 260518A
  17. GRB 260518A: AstroSat CZTI detection of a long burst
  18. GRB 260516D: SVOM/ECLAIRs refined analysis
  19. GRB 260515A: SVOM/ECLAIRs refined analysis
  20. GRB 260421B: radio detection with the VLA
  21. GRID detection of GRB 260511A
  22. GRB 260516D: EP-FXT follow-up observation
  23. GRB 260516D: GOTO optical counterpart detection
  24. GRB 260516D: LCO optical observations
  25. GRB 260515A: further Liverpool Telescope observations
  26. GRB 260516D: SVOM/COLIBRÍ (FM-GFT) optical observations
  27. GRB 260516D: GROWTH-India Telescope optical detection
  28. GRB 260516D: SVOM/VT optical bright candidate
  29. GRB 260516D: FRAM-ORM optical limit
  30. SVOM GRB260516D: Global MASTER-Net observations report
  31. GRB 260516D: SVOM possible detection of a burst
  32. Konus-Wind detection of GRB 260515A
  33. GRB 260515A: LCO optical counterpart detection
  34. GRB 260515A: SVOM/COLIBRÍ (FM-GFT) optical observations
  35. GRB 260515A: EP-FXT follow-up observation
  36. EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations
  37. EP260514a: NOT optical counterpart confirmation
  38. EP260514a: TRT optical counterpart candidate
  39. EP260514a: SVOM/VT optical candidate
  40. GRB 260515A: SVOM/VT optical observations
  41. GRB 260515A: OHP/T193 optical observations
  42. EP260514a: COLIBRÍ optical upper limits
  43. GRID detection of GRB 260507A
  44. GRB 260515A: LCO optical observations
  45. SVOM GRB 260515A: Global MASTER-Net observations report
  46. GRB 260515A: NOT optical observations.
  47. SVOM GRB 260515A: MASTER OT J151044.43+243321.7 optical counterpart detection
  48. GRB 260515A: SVOM/VT optical candidate from VHF data
  49. GRB 260515A: JinShan optical counterpart candidate
  50. GRB 260515A: SVOM detection of a burst
  51. GRB 260510C: Glowbug gamma-ray detection
  52. IceCube-260504A: No Candidate Transients from the Zwicky Transient Facility
  53. EP260514a: GROWTH-India Telescope optical upper limit
  54. GRB 260511B: NOT optical observations
  55. Konus-Wind detection of GRB 260512A
  56. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  57. EP260514a: Einstein Probe detection of a fast X-ray transient
  58. IPN triangulation of GRB 260512A
  59. GRB 260511B: Mephisto multi-band optical followup
  60. GRB 260512A: AstroSat CZTI detection
  61. EP260512a: EP-FXT follow-up observation
  62. EP260507a: Xinglong Schmidt optical counterpart detection
  63. GRB 260511B: further SAO RAS optical observations
  64. GRB 260509A: SVOM/VT optical observations
  65. Konus-Wind detection of GRB 260511B
  66. EP260512a: COLIBRÍ optical upper limits
  67. EP260512a: Einstein Probe detection of an X-ray transient
  68. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  69. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  70. GRB 260512A: NuSTAR detection of prompt emission
  71. GRB 260511A: Glowbug gamma-ray detection
  72. Konus-Wind detection of GRB 260511A
  73. MASS-Cube (GRID 2.0) detection of GRB 260511A
  74. MASS-Cube (GRID 2.0) detection of GRB 260507A
  75. GRB 260511B: SAO RAS optical observations
  76. GRB 260510D: Glowbug gamma-ray detection of a likely short burst
  77. GRB 260511B: FRAM-ORM optical detection
  78. GRB 260511A: EP-FXT follow-up observation
  79. GRB 260511B: EP-FXT follow-up observation
  80. GRB 260511B: LCO optical counterpart detection
  81. GRB260511B: MAO/AZT-22 optical observations
  82. GRB 260511A: SVOM/VT optical observations
  83. GRB 260511B: LCO optical observations
  84. GRB 260511B: OHP/T193 spectroscopic observations
  85. GRB 260511B: GOTO optical counterpart detection
  86. GRB 260511B: Xinglong 2.16m/BEFOSC redshift confirmation
  87. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) further optical observations
  88. GRB 260511B: SVOM/VT optical observations
  89. GRB 260511B: SVOM/COLIBRÍ (FM-GFT) optical observations
  90. GRB 260510B: EP-FXT follow-up observation
  91. GRB 260510C: Fermi GBM Observation
  92. GRB 260511A: REM near-infrared detection
  93. GRB 260511B: GROWTH-India Telescope optical observations
  94. GRB 260511B: AstroSat CZTI detection
  95. GRB 260506B: Glowbug gamma-ray detection
  96. GRB 260506A: Glowbug gamma-ray detection of a short burst
  97. GRB 260511B: J-band observations by the SYSU 80 cm infrared telescope
  98. GRB 260511B: NuSTAR detection of prompt emission
  99. GRB 260511A: NuSTAR detection of prompt emission
  100. GRB 260511B: Fermi GBM Detection

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