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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"

24541 results found.

  1. LIGO/Virgo/KAGRA S231001aq: Identification of a GW compact binary merger candidate
  2. GRB 230930A: Fermi GBM Final Real-time Localization
  3. LIGO/Virgo/KAGRA S230930al: Identification of a GW compact binary merger candidate
  4. NuEm-230927A: Swift-XRT follow-up
  5. LIGO/Virgo/KAGRA S230928cb: Identification of a GW compact binary merger candidate
  6. LIGO/Virgo/KAGRA S230927be: Updated Sky localization
  7. LIGO/Virgo/KAGRA S230927l: Updated Sky localization
  8. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230927A
  9. LIGO/Virgo/KAGRA S230927be: Identification of a GW compact binary merger candidate
  10. LIGO/Virgo/KAGRA S230927l: Identification of a GW compact binary merger candidate
  11. Swift Triggers 1192740, 1192742 and 1192743 are not astrophysical events
  12. LIGO/Virgo/KAGRA S230922q: Updated Sky localization
  13. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  14. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  15. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  16. LIGO/Virgo/KAGRA S230924an: Updated Sky localization
  17. LIGO/Virgo/KAGRA S230924an: Identification of a GW compact binary merger candidate
  18. LIGO/Virgo/KAGRA S230922g: Updated Sky localization
  19. LIGO/Virgo/KAGRA S230922g: Identification of a GW compact binary merger candidate
  20. LIGO/Virgo/KAGRA S230922q: Identification of a GW compact binary merger candidate
  21. LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
  22. GRB 230921A: Fermi GBM Final Real-time Localization
  23. IPN triangulation of GRB 230919A (short)
  24. GRB 230919A: Fermi GBM Observation
  25. Fermi GBM Statement for Trigger 716527670/230916144
  26. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  27. LIGO/Virgo/KAGRA S230920al: Updated Sky localization
  28. LIGO/Virgo/KAGRA S230919bj: Updated Sky localization
  29. GRB 230919A: AstroSat CZTI detection
  30. LIGO/Virgo/KAGRA S230920al: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo/KAGRA S230919bj: Identification of a GW compact binary merger candidate
  32. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  33. GRB 230919A: Fermi GBM Final Real-time Localization
  34. GRB 230918B: Fermi GBM Final Real-time Localization
  35. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  36. GRB 230915A: Fermi GBM observation
  37. LIGO/Virgo/KAGRA S230918aq: Retraction of GW compact binary merger candidate
  38. GRB 230918A: Fermi GBM Final Real-time Localization
  39. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  40. GRB 230916A: NuSTAR Discovery of Prompt Emission from a Potential GRB
  41. GRB 230911A: Fermi GBM Observation
  42. Swift GRB230916.18: Global MASTER-Net observations report
  43. Fermi trigger No 716572242: Global MASTER-Net observations report
  44. LIGO/Virgo/KAGRA S230904n: Correction of the coordinates of the ZTF candidate counterpart
  45. Fermi trigger No 716544961: Global MASTER-Net observations report
  46. Fermi-LAT gamma-ray observations of IceCube-230914A
  47. GRB 230915A: Swift/BAT-GUANO detection of a burst
  48. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  49. GRB 230911D: GRBAlpha detection
  50. Swift GRB230916.19: Global MASTER-Net observations report
  51. Swift GRB230916.18: Global MASTER-Net observations report
  52. Swift GRB230916.13: Global MASTER-Net observations report
  53. Swift GRB230916.12: Global MASTER-Net observations report
  54. Swift GRB230916.11: Global MASTER-Net observations report
  55. GRB 230906A: optical counterpart
  56. IceCube-230914A: Upper limits from a search for additional neutrino events in IceCube
  57. Fermi trigger No 716449174: Global MASTER-Net observations report
  58. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  59. IceCube Alert 230914.22: Global MASTER-Net observations report
  60. Fermi trigger No 716419312: Global MASTER-Net observations report
  61. LIGO/Virgo/KAGRA S230914ak: Updated Sky localization
  62. GRB 230812B: Bad Time Intervals for Fermi GBM data
  63. IceCube-230914A - IceCube observation of a high-energy neutrino candidate track-like event
  64. LIGO/Virgo/KAGRA S230914ak: Identification of a GW compact binary merger candidate
  65. Swift GRB230913.70: Global MASTER-Net observations report
  66. GRB 230913A: Fermi GBM Observation
  67. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  68. Swift GRB230913.70: Global MASTER-Net observations report
  69. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  70. Fermi GRB 230913A: Global MASTER-Net observations report
  71. GRB 230911A: GOTO optical counterpart candidate
  72. GRB 230913A: Fermi GBM Final Real-time Localization
  73. GRB 230911D: NuSTAR Detection of Prompt Emission
  74. GRB 230911C: Swift-XRT refined Analysis
  75. GRB 230911C: Swift-BAT refined analysis
  76. LIGO/Virgo/KAGRA S230911ae: Updated Sky localization
  77. GRB 230906A: Chandra detection of the X-ray afterglow
  78. Swift GRB 230911C: Global MASTER-Net observations report
  79. GRB 230911D: Fermi GBM observation
  80. IPN triangulation of GRB 230911D (long)
  81. GRB 230911D: Fermi-LAT detection
  82. GRB230911C: LCOGT Optical Upper Limits
  83. LIGO/Virgo/KAGRA S230911ae: Identification of a GW compact binary merger candidate
  84. GRB 230911B: GRBAlpha and VZLUSAT-2 joint detection
  85. Fermi trigger No 716145795: Global MASTER-Net observations report
  86. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  87. Konus-Wind detection of GRB 230811D
  88. GRB 230911D: BALROG localization (Fermi Trigger 716111594/ GRB 230911329)
  89. GRB 230911D: Fermi GBM Final Localization
  90. GRB 230911C: Swift detection of a burst
  91. Fermi GRB 230911B: Global MASTER-Net observations report
  92. GRB 230911B: Fermi GBM Final Real-time Localization
  93. GRB 230911A: Fermi GBM Final Real-time Localization
  94. GRB 230903A: TESS observations of optical emission
  95. GRB 230906A: AstroSat CZTI detection
  96. GRB 230910A: Fermi GBM Final Real-time Localization
  97. GRB 230908A: GRBAlpha detection
  98. LIGO/Virgo/KAGRA S230908b: one counterpart neutrino candidate from IceCube neutrino searches
  99. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  100. GRB 230906A: Swift-XRT observations

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