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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

27342 results found.

  1. Fermi GRB 260516C: Global MASTER-Net observations report
  2. SVOM GRB260516.86: Global MASTER-Net observations report
  3. GRB 260516D: SVOM possible detection of a short faint burst
  4. GRB 260515A: LCO optical counterpart detection
  5. GRB 260515A: SVOM/COLIBRÍ (FM-GFT) further optical observations
  6. EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations
  7. EP260514a: NOT optical counterpart confirmation
  8. EP260514a: TRT optical counterpart candidate
  9. EP260514a: SVOM/VT optical candidate
  10. Fermi GRB 260516B: Global MASTER-Net observations report
  11. GRB 260515A: OHP/T193 optical observations
  12. EP260514a: COLIBRÍ optical upper limits
  13. GRB 260515A: LCO optical observations
  14. SVOM GRB 260515A: Global MASTER-Net observations report
  15. SVOM GRB 260515A: MASTER OT J151044.43+243321.7 optical counterpart detection
  16. GRB 260515A: SVOM/VT optical candidate from VHF data
  17. GRB 260515A: JinShan optical counterpart candidate
  18. GRB 260515A: SVOM detection of a burst
  19. GRB 260510C: Glowbug gamma-ray detection
  20. EP260514a: GROWTH-India Telescope optical upper limit
  21. GRB 260511B: GMG Optical Upper Limit
  22. EP260514a: Global MASTER-Net observations report
  23. EP260514a: Einstein Probe detection of a fast X-ray transient
  24. EP260512a: LCO optical upper limits
  25. GRB 260511B: Mephisto multi-band optical followup
  26. Fermi GRB 260514A: Global MASTER-Net observations report
  27. GRB 260512A: AstroSat CZTI detection
  28. EP260512a: EP-FXT follow-up observation
  29. EP260507a: Xinglong Schmidt optical counterpart detection
  30. EP260512a: Global MASTER-Net observations report
  31. Fermi GRB 260513A: Global MASTER-Net observations report
  32. Fermi GRB 260512A: Global MASTER-Net observations report
  33. GRB 260511B: further SAO RAS optical observations
  34. GRB 260509A: SVOM/VT optical observations
  35. The EP-WXT trigger 01709262036 is likely a flaring star
  36. EP260512a: COLIBRÍ optical upper limits
  37. EP260512a: Einstein Probe detection of an X-ray transient
  38. GRB 260511B: further J-band observations by the SYSU 80 cm infrared telescope
  39. GRB 260511B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
  40. GRB 260512A: NuSTAR detection of prompt emission
  41. GRB 260509A: Infrared J and Hs observations with MDM/MIRAGE
  42. GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE
  43. EP260507a: Infrared J and Hs upper limits with MDM/MIRAGE
  44. GRB 260511A: Glowbug gamma-ray detection
  45. GRB 260511B: SAO RAS optical observations
  46. GRB 260510D: Glowbug gamma-ray detection of a likely short burst
  47. GRB 260511B: FRAM-ORM optical detection
  48. GRB 260511A: EP-FXT follow-up observation
  49. GRB 260511B: EP-FXT follow-up observation
  50. GRB 260511B: LCO optical counterpart detection
  51. GRB260511B: MAO/AZT-22 optical observations
  52. GRB 260511B: LCO optical observations
  53. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) further optical observations
  54. GRB 260511B: SVOM/COLIBRÍ (FM-GFT) optical observations
  55. GRB 260510B: EP-FXT follow-up observation
  56. GRB 260510C: Fermi GBM Observation
  57. GRB 260509A: SAO RAS optical observations
  58. GRB 260511A: REM near-infrared detection
  59. GRB 260511B: GROWTH-India Telescope optical observations
  60. GRB 260506B: Glowbug gamma-ray detection
  61. GRB 260506A: Glowbug gamma-ray detection of a short burst
  62. GRB 260511B: J-band observations by the SYSU 80 cm infrared telescope
  63. GRB 260511B: NuSTAR detection of prompt emission
  64. GRB 260511A: NuSTAR detection of prompt emission
  65. GRB 260511B: Fermi GBM Detection
  66. GRB 260511B: SVOM/VT optical observation with VHF data
  67. GRB 260511B: TRT optical observation
  68. GRB 260511B : MITSuME Akeno optical afterglow candidate detection
  69. GRB 260511A: Fermi GBM Detection
  70. GRB 260511B SVOM/C-GFT optical counterpart detection
  71. EP260509a: LCO optical upper limits
  72. GRB 260511A: UTGO H50 optical afterglow observation
  73. GRB 260511B: SVOM detection of a burst
  74. GRB 260510C: EP-FXT follow-up observation
  75. EP260509a: EP-FXT non-detection and upper limit
  76. GRB 260511A: SVOM/VT optical observation with VHF data
  77. Fermi GRB 260511A: Global MASTER-Net observations report
  78. GRB 260511A: KAIT optical afterglow observations
  79. GRB 260511A: LCO optical afterglow detection
  80. GRB 260511A: SVOM/COLIBRÍ (FM-GFT) optical counterpart
  81. GRB 260511A: TRT optical counterpart detection
  82. GRB 260511A: SVOM detection of a bright burst
  83. GRB 260511A: BALROG localization (Fermi Trigger 800172815 / GRB 260511259)
  84. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  85. GRB 260510C: MAXI/GSC detection
  86. EP260509a: Global MASTER-Net observations report
  87. Fermi GBM Sub-Threshold Detection of GRB 260510B
  88. GRB 260510C: SVOM detection of a burst
  89. GRB 260510B: LCO optical upper limits
  90. EP260509a: Einstein Probe detection of an X-ray transient
  91. GRB 260509A: Liverpool Telescope optical observations
  92. GRB 260510B: SVOM detection of a burst
  93. GRB 260509A: LCO optical observations
  94. SVOM GRB 260509A: MASTER-OAFA optical observation
  95. Fermi GRB 260510A: Global MASTER-Net observations report
  96. GRB 260509A: KAIT optical observations
  97. GRB 260509A: SVOM/COLIBRÍ (FM-GFT) observations
  98. GRB 260509A: SVOM/VT optical candidate with VHF data
  99. GRB 260509A: LCO optical counterpart detection
  100. GRB 260509A: SVOM detection of a burst

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