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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').
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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"

11748 results found.

  1. EP260214b: Optical upper limit with Kinder observations
  2. EP260214a: Optical upper limits with Kinder observations
  3. EP260214b: EP-FXT follow-up observation
  4. EP260214a: COLIBRÍ optical upper limits
  5. EP260214a: refined analysis of the EP-FXT observation
  6. EP260214b: Einstein Probe detection of a fast X-ray transient
  7. EP260214a: Einstein Probe detection of an X-ray transient
  8. GRB 260212A: AstroSat CZTI detection
  9. EP260213a: Optical upper limits with Kinder observations
  10. EP260213a: Mondy R-band optical upper limit
  11. EP260213a: NUTTelA-TAO Early Optical Limits
  12. EP260213a: refined analysis of the EP-FXT observation
  13. EP260213a: Einstein Probe detection of a fast X-ray transient
  14. GRB 260211A: GOTO optical upper limit
  15. Konus-Wind detection of GRB 260207B
  16. GRB260131A/B: 3.6m DOT Optical Observations
  17. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  18. GRB 260211A: SVOM detection of a burst
  19. Konus-Wind detection of GRB 260209B
  20. Konus-Wind detection of GRB 260127B
  21. EP260210a: Global MASTER-Net observations report
  22. EP260210a: refined analysis of the EP-FXT observation
  23. EP260209a: Einstein Probe detection of a fast X-ray transient
  24. EP260210a: Optical upper limits with Kinder observations
  25. GRB 260208C: AstroSat CZTI detection
  26. EP260210a: COLIBRÍ optical upper limit
  27. EP260210a: Einstein Probe detection of an X-ray transient
  28. GRB 260207B: AstroSat CZTI detection
  29. GRB 260208B: AstroSat CZTI detection of a bright long burst
  30. Fermi GRB 260209A: Global MASTER-Net observations report
  31. GRB 260208A: Mondy optical observations
  32. GRB 260208A: 1.3m DFOT optical detection
  33. GRB 260208B: EP-FXT observation
  34. Fermi GRB 260208C: Global MASTER-Net observations report
  35. GRB 260208B: Fermi-LAT detection
  36. GRB 260208A: Fermi-LAT detection
  37. Fermi trigger No 792135758: Global MASTER-Net observations report
  38. GRB 260206A (or XRB from 4U 0513-40): MAXI/GSC detection
  39. GRB 260204A: Swift-XRT observations
  40. GRB 260204A : MASTER Global robotic net optical observations
  41. GRB 260204A: SVOM detection of a burst
  42. GRB 260121A: 239Alferov CubeSat detection
  43. Konus-Wind detection of GRB 260121A
  44. GRB 260131A/B: GTC/OSIRIS+ redshift confimation
  45. GRB 260131A/B: EP/FXT X-ray afterglow detection
  46. Konus-Wind detection of GRB 260128A / EP260128a
  47. Konus-Wind detection of GRB 260131A/B
  48. GRB 260131A/B: GOTO candidate optical counterpart consistent with the MAXI localisation
  49. EP260131a: refined analysis of the EP-WXT and autonomous EP-FXT observations
  50. GRB 260131B: MAXI/GSC detection
  51. GRB 260127B: AstroSat CZTI detection
  52. GRB 260130A: Fermi GBM Detection
  53. EP260131a: Einstein Probe detection of an X-ray transient
  54. GRB 260127B: Fermi GBM Detection
  55. GRB 260130A: Fermi GBM Final Real-time Localization
  56. EP260128a: J band upper limit by SYSU 80cm infrared telescope
  57. GRB 260127A: Swift-BAT refined analysis
  58. GRB 260128B: SVOM detection of a burst through offline search
  59. IPN triangulation of GRB 260127B (short)
  60. GRB 260127A: INASAN-Kislovodsk, SAO RAS, and Terskol K-800 optical observations
  61. EP260128a: refined analysis of the EP-WXT and autonomous EP-FXT observations
  62. EP260128a: Einstein Probe detection of an X-ray transient
  63. Fermi GRB 260127A: Global MASTER-Net observations report
  64. GRB 260127A: Swift-XRT refined Analysis
  65. GRB 260127B: GOTO candidate optical counterpart
  66. Fermi GRB 260127B: Global MASTER-Net observations report
  67. GRB 260127B: Fermi GBM Final Real-time Localization
  68. GRB 260127A: Swift detection of a burst
  69. EP260126a: Optical upper limit with Kinder observations
  70. EP260126a: Einstein Probe detection of a fast X-ray transient
  71. Fermi-LAT Gamma-ray Observations of IceCube-260125A
  72. Konus-Wind detection of GRB 260120B
  73. GRB 260120A: AstroSat CZTI detection
  74. GRB 260122B: Swift-BAT refined analysis
  75. GRB 260120B: AstroSat CZTI detection
  76. EP260119a: Assy AZT-20 optical observations
  77. EP260119a: Mondy and SAO RAS optical upper limits
  78. Fermi GRB 260120C: Global MASTER-Net observations report
  79. GRB 260120B: Swift-XRT refined Analysis
  80. GRB 260120B: Fermi GBM Observation
  81. SVOM GRB260121.06: Global MASTER-Net observations report
  82. GRB 260120C: Fermi GBM Final Real-time Localization
  83. GRB 260101A: 239Alferov CubeSat detection
  84. EP260116a: COLIBRÍ observations of a tentative optical rebrightening
  85. Swift GRB260120B: Global MASTER-Net observations report
  86. GRB 260120B: Fermi GBM Final Real-time Localization
  87. Fermi trigger No 790601190: Global MASTER-Net observations report
  88. Fermi trigger No 790570272: Global MASTER-Net observations report
  89. GRB 260120A: Fermi GBM Final Real-time Localization
  90. EP260119a: update of EP-FXT follow-up observation
  91. SVOM GRB260119.90: Global MASTER-Net observations report
  92. EP260116a: COLIBRÍ detection of a fading optical source
  93. EP260119a: Global MASTER-Net observations report
  94. GRB 260117A: ZTSh optical upper limit
  95. EP260119a: COLIBRÍ optical counterpart candidate
  96. EP260119a: preliminary result from the EP-FXT observation
  97. GRB 260110A: SVOM detection of a burst through offline search
  98. EP260119a: EP-WXT detection of a fast X-ray transient
  99. Swift GRB260118.48: Global MASTER-Net observations report
  100. Fermi-LAT Gamma-ray Observations of IceCube-260115A

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