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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"

28252 results found.

  1. Konus-Wind detection of GRB 260518A
  2. GRB 260516D: SVOM/ECLAIRs refined analysis
  3. GRB 260421B: radio detection with the VLA
  4. GRB 260509A: CrAO ZTSh optical upper limit
  5. GRB 260516D: GOTO optical counterpart detection
  6. GRB 260516D: LCO optical observations
  7. GRB 260515A: further Liverpool Telescope observations
  8. GRB 260516D: SVOM/COLIBRÍ (FM-GFT) optical observations
  9. GRB 260516D: GROWTH-India Telescope optical detection
  10. GRB 260516D: SVOM/VT optical bright candidate
  11. GRB 260515A: CrAO ZTSh BVRI optical observations
  12. Fermi GRB 260516C: Global MASTER-Net observations report
  13. SVOM GRB260516D: Global MASTER-Net observations report
  14. GRB 260516D: SVOM possible detection of a burst
  15. GRB 260515A: LCO optical counterpart detection
  16. GRB 260515A: SVOM/COLIBRÍ (FM-GFT) optical observations
  17. EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations
  18. EP260514a: NOT optical counterpart confirmation
  19. EP260514a: TRT optical counterpart candidate
  20. EP260514a: SVOM/VT optical candidate
  21. Fermi GRB 260516B: Global MASTER-Net observations report
  22. GRB 260515A: OHP/T193 optical observations
  23. EP260514a: COLIBRÍ optical upper limits
  24. GRB 260515A: LCO optical observations
  25. SVOM GRB 260515A: Global MASTER-Net observations report
  26. SVOM GRB 260515A: MASTER OT J151044.43+243321.7 optical counterpart detection
  27. GRB 260515A: SVOM/VT optical candidate from VHF data
  28. GRB 260515A: JinShan optical counterpart candidate
  29. GRB 260515A: SVOM detection of a burst
  30. GRB 260510C: Glowbug gamma-ray detection
  31. EP260514a: GROWTH-India Telescope optical upper limit
  32. GRB 260511B: GMG Optical Upper Limit
  33. EP260514a: Global MASTER-Net observations report
  34. EP260514a: Einstein Probe detection of a fast X-ray transient
  35. EP260512a: LCO optical upper limits
  36. GRB 260511B: Mephisto multi-band optical followup
  37. Fermi GRB 260514A: Global MASTER-Net observations report
  38. GRB 260512A: AstroSat CZTI detection
  39. EP260512a: EP-FXT follow-up observation
  40. EP260507a: Xinglong Schmidt optical counterpart detection
  41. EP260512a: Global MASTER-Net observations report
  42. Fermi GRB 260513A: Global MASTER-Net observations report
  43. Fermi GRB 260512A: Global MASTER-Net observations report
  44. GRB 260511B: further SAO RAS optical observations
  45. GRB 260509A: SVOM/VT optical observations
  46. The EP-WXT trigger 01709262036 is likely a flaring star
  47. EP260512a: COLIBRÍ optical upper limits
  48. EP260512a: Einstein Probe detection of an X-ray transient
  49. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  50. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  51. GRB 260512A: NuSTAR detection of prompt emission
  52. GRB 260509A: Infrared J and Hs observations with MDM/MIRAGE
  53. GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE
  54. EP260507a: Infrared J and Hs upper limits with MDM/MIRAGE
  55. GRB 260511A: Glowbug gamma-ray detection
  56. GRB 260511B: SAO RAS optical observations
  57. GRB 260510D: Glowbug gamma-ray detection of a likely short burst
  58. GRB 260511B: FRAM-ORM optical detection
  59. GRB 260511A: EP-FXT follow-up observation
  60. GRB 260511B: EP-FXT follow-up observation
  61. GRB 260511B: LCO optical counterpart detection
  62. GRB260511B: MAO/AZT-22 optical observations
  63. GRB 260511B: LCO optical observations
  64. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) further optical observations
  65. GRB 260511B: SVOM/COLIBRÍ (FM-GFT) optical observations
  66. GRB 260510B: EP-FXT follow-up observation
  67. GRB 260510C: Fermi GBM Observation
  68. GRB 260509A: SAO RAS optical observations
  69. GRB 260511A: REM near-infrared detection
  70. GRB 260511B: GROWTH-India Telescope optical observations
  71. GRB 260506B: Glowbug gamma-ray detection
  72. GRB 260506A: Glowbug gamma-ray detection of a short burst
  73. GRB 260511B: J-band observations by the SYSU 80 cm infrared telescope
  74. GRB 260511B: NuSTAR detection of prompt emission
  75. GRB 260511A: NuSTAR detection of prompt emission
  76. GRB 260511B: Fermi GBM Detection
  77. GRB 260511B: SVOM/VT optical observation with VHF data
  78. GRB 260511B: TRT optical observation
  79. GRB 260511B : MITSuME Akeno optical afterglow candidate detection
  80. GRB 260511A: Fermi GBM Detection
  81. GRB 260511B SVOM/C-GFT optical counterpart detection
  82. EP260509a: LCO optical upper limits
  83. GRB 260511A: UTGO H50 optical afterglow observation
  84. GRB 260511B: SVOM detection of a burst
  85. GRB 260510C: EP-FXT follow-up observation
  86. EP260509a: EP-FXT non-detection and upper limit
  87. GRB 260511A: SVOM/VT optical observation with VHF data
  88. Fermi GRB 260511A: Global MASTER-Net observations report
  89. GRB 260511A: KAIT optical afterglow observations
  90. GRB 260511A: LCO optical afterglow detection
  91. GRB 260511A: SVOM/COLIBRÍ (FM-GFT) optical counterpart
  92. GRB 260511A: TRT optical counterpart detection
  93. GRB 260511A: SVOM detection of a bright burst
  94. GRB 260511A: BALROG localization (Fermi Trigger 800172815 / GRB 260511259)
  95. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  96. GRB 260510C: MAXI/GSC detection
  97. EP260509a: Global MASTER-Net observations report
  98. Fermi GBM Sub-Threshold Detection of GRB 260510B
  99. GRB 260510C: SVOM detection of a burst
  100. GRB 260510B: LCO optical upper limits

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