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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"

37789 results found.

  1. GRB 231104A: 3.6m DOT optical upper limit
  2. Fermi-LAT gamma-ray observations of IceCube-231103A
  3. GRB 231104A: NOT upper limit
  4. GRB 231104A: Fermi GBM Observation
  5. GRB 231104B: Fermi GBM Final Real-time Localization
  6. Fermi GRB 231103A: Global MASTER-Net observations report
  7. GRB 231104A: AKO Upper Limit
  8. GRB 231104A: AstroSat CZTI detection
  9. GRB 231104A: Swift-XRT refined Analysis
  10. GRB 231104A: Fermi-LAT detection
  11. GRB 231104A: Swift/UVOT Upper Limits
  12. GRB 231104A: Enhanced Swift-XRT position
  13. GRB231104A: LCOGT Optical Upper Limits
  14. GRB 231104A: Swift detection of a bright burst
  15. GRB 231104A: Fermi GBM Final Real-time Localization
  16. GRB 231103A: Fermi GBM Final Real-time Localization
  17. IceCube-231103A - IceCube observation of a high-energy neutrino candidate track-like event
  18. Fermi-LAT gamma-ray observations of IceCube-231027A
  19. GRB 231101A: Glowbug gamma-ray detection
  20. GRB 231024A: GRANDMA observations of AT2023vuc/GOTO23baj candidate
  21. Fermi trigger No 720498201: Global MASTER-Net observations report
  22. GRB 231101A: Fermi GBM Final Real-time Localization
  23. GRB 231030B: GRBAlpha detection
  24. GRB 231028B: VZLUSAT-2 detection
  25. Fermi trigger No 720415645: Global MASTER-Net observations report
  26. GRB 231030B: Fermi GBM Detection
  27. GRB 231030B: AstroSat CZTI detection
  28. Fermi GRB 231030B: Global MASTER-Net observations report
  29. IPN triangulation of GRB 231020A
  30. GRB 231030B: BALROG localization (Fermi Trigger 720388704 / GRB 231030832)
  31. GRB 231030B: Fermi GBM Final Real-time Localization
  32. GRB 231028A: Swift-BAT refined analysis
  33. LIGO/Virgo/KAGRA S231029y: Upper limits from Swift/BAT-GUANO
  34. GRB 231024A: AKO Optical Counterpart Candidate
  35. GRB 231028A: CALET Gamma-Ray Burst Monitor detection
  36. Fermi GRB 231030A: Global MASTER-Net observations report
  37. GRB 231030A: Fermi GBM Final Real-time Localization
  38. GRID detection of GRB 231020A
  39. GRB 231028A: AstroSat CZTI detection
  40. GRB 231028A: Glowbug gamma-ray detection
  41. GRB 231028A: Fermi GBM Detection
  42. Fermi trigger No 720224759: Global MASTER-Net observations report
  43. Swift GRB 231028A: Global MASTER-Net observations report
  44. GRB 231028A: Swift detection of a burst
  45. GRB 231028A: Fermi GBM Final Real-time Localization
  46. IceCube-231027A - IceCube observation of a high-energy neutrino candidate track-like event
  47. GRB 231019A: Glowbug gamma-ray detection
  48. GRB 231025A: Fermi GBM Observation
  49. GRB 231024A: Fermi GBM Observation
  50. GRB 231025A: Swift/BAT-GUANO detection of a likely short burst
  51. GRB 231025A: Fermi GBM Final Localization
  52. GRB 231024A: X-shooter spectroscopy of AT2023vuc/GOTO23baj reveals a young supernova with flash ionisation features
  53. GRB 231024A: LCOGT and ZTF detections of the GOTO optical counterpart candidate
  54. GRB 231020A: AstroSat CZTI detection
  55. GRB 231020B: AstroSat CZTI detection
  56. GRB 231024A: GOTO optical counterpart candidate
  57. GRB 231024A: Fermi GBM Final Localization
  58. Fermi trigger No 719846439: Global MASTER-Net observations report
  59. GRB 231018A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  60. LIGO/Virgo/KAGRA S231020bw: Upper limits from Swift/BAT-GUANO
  61. GRB 231020A: Fermi GBM Detection
  62. GRID detection of GRB 231004A
  63. GRB 231017A: Mondy optical observations. A possible candidate for an afterglow or host galaxy.
  64. GRB 231019A: VZLUSAT-2 detection
  65. GRB 231018A: VZLUSAT-2 detection
  66. GRB 231020B: BALROG localization (Fermi Trigger 719530557 / GRB 231020900)
  67. GRB 231020B: Fermi GBM Final Real-time Localization
  68. GRB 231020A: BALROG localization (Fermi Trigger / GRB 231020790)
  69. LIGO/Virgo/KAGRA S231020ba: Upper limits from Fermi-GBM Observations
  70. GRB 231015A: NuSTAR Detection of Prompt Emission
  71. Fermi GRB 231020A: Global MASTER-Net observations report
  72. GRB 231020A: Fermi GBM Final Real-time Localization
  73. GRB 231012A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  74. GRB 231017A: 1.3m DFOT Optical upper limit
  75. IceCube-231004A: Upper limits from Fermi-GBM Observations
  76. GRB 231018A: GRBAlpha detection
  77. GRB 231018A: CALET Gamma-Ray Burst Monitor detection
  78. Fermi GRB 231019A: Global MASTER-Net observations report
  79. GRB 231018A: Glowbug gamma-ray detection
  80. Konus-Wind detection of GRB 231018A
  81. IPN triangulation of GRB 231018A
  82. GRB 231017A: Swift/UVOT Upper Limit
  83. GRB 230911C: ATCA detection of possible radio counterpart
  84. GRB 231019A: Fermi GBM Final Real-time Localization
  85. GRB 231017A: GOTO optical upper limits
  86. GRB 231017A: JinShan optical upper limit
  87. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  88. GRB 231017A: Las Cumbres optical upper limit
  89. GRB 231015A: Glowbug gamma-ray detection
  90. GRB 231017A: LCOGT Optical Upper Limits
  91. GRB231017A: GROWTH-India upper limits on the optical afterglow
  92. GRB 231015A: AstroSat CZTI detection
  93. GRB 231018A: Fermi GBM Detection
  94. GRB 231017A: Fermi GBM Detection
  95. GRB 231017A: Swift-XRT observations
  96. GRB 231012B may not be a GRB
  97. GRB 231018A: BALROG localization (Fermi Trigger / GRB 231018521)
  98. GRB 231018A: Fermi GBM Final Real-time Localization
  99. GRB 231017A: Swift ToO observations
  100. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst

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