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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. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  2. GRB 230919A: Fermi GBM Final Real-time Localization
  3. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  4. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  5. GRB 230918B: Fermi GBM Final Real-time Localization
  6. GRB 230918A (short): Glowbug gamma-ray detection
  7. GRB 230916B: Glowbug gamma-ray detection
  8. AT 2023sva: NOT observations of the ZTF candidate afterglow
  9. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  10. LIGO/Virgo/KAGRA S230918aq: Retraction of GW compact binary merger candidate
  11. GRB 230812B: Radio observations with the uGMRT
  12. GRB 230918A: Fermi GBM Final Real-time Localization
  13. GRB 230917A: AstroSat CZTI detection
  14. GRB 230915B: Glowbug gamma-ray detection
  15. GRB 230911A: Fermi GBM Observation
  16. LIGO/Virgo/KAGRA S230904n: Correction of the coordinates of the ZTF candidate counterpart
  17. GRB 230915A: Swift/BAT-GUANO detection of a burst
  18. GRB 230911D: GRBAlpha detection
  19. GRB 230906A: optical counterpart
  20. GRB 230911A: Swift-XRT afterglow detection
  21. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  22. GRB 230913A: Glowbug gamma-ray detection
  23. IceCube-230914A - IceCube observation of a high-energy neutrino candidate track-like event
  24. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  25. GRB 230911A: Swift ToO observations
  26. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  27. GRB 230913A: Fermi GBM Final Real-time Localization
  28. GRB 230908A: CALET Gamma-Ray Burst Monitor detection
  29. GRB 230911D: NuSTAR Detection of Prompt Emission
  30. GRB 230911B: AstroSat CZTI detection
  31. GRB 230911C: Swift-XRT refined Analysis
  32. GRB230911C: BOOTES-6/DPRT optical upper limit
  33. GRB 230906A: Chandra detection of the X-ray afterglow
  34. IPN triangulation of GRB 230911D (long)
  35. GRB 230911D: Fermi-LAT detection
  36. GRB230911C: LCOGT Optical Upper Limits
  37. GRB 230911C: Swift/UVOT Upper Limits
  38. GRB 230911B: GRBAlpha and VZLUSAT-2 joint detection
  39. GRB 230911C: GOTO optical upper limits
  40. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  41. GRB 230911B: correction to the KW GCN 34659
  42. Konus-Wind detection of GRB 230811D
  43. GRB 230911C: Enhanced Swift-XRT position
  44. GRB 230911D: Fermi GBM Final Localization
  45. GRB 230911C: Swift detection of a burst
  46. GRB 230911B: Fermi GBM Final Real-time Localization
  47. GRB 230911A: Fermi GBM Final Real-time Localization
  48. GRB 230906A: BlackGEM upper limits
  49. GRB 230903A: TESS observations of optical emission
  50. GRB 230906A: AstroSat CZTI detection
  51. GRB 230910A: Fermi GBM Final Real-time Localization
  52. GRB 230908A: GRBAlpha detection
  53. GRB 230908A: AstroSat CZTI detection
  54. Glowbug gamma-ray detection GRB 230905B
  55. GRB 230906A: Swift/UVOT Upper Limits
  56. GRID detection of GRB 230827A
  57. GRB 230906A: Swift-XRT observations
  58. Konus-Wind detection of GRB 230906A (short)
  59. IPN triangulation of GRB 230906A (short)
  60. GRB 230906A: Swift ToO observations
  61. GRB 230905B: AstroSat CZTI detection
  62. Swift Attitude Control Affecting Some UVOT Images
  63. GRB 230812B: Chandra late-time detection of the X-ray afterglow
  64. GRB 230906A: Fermi GBM Final Localizationn
  65. GRB 230905B: GECAM-C detection of a long burst
  66. GRB 230905A: Fermi GBM Final Real-time Localization
  67. GRB 230903A: Swift-XRT refined Analysis
  68. GRB 230903A: Enhanced Swift-XRT position
  69. GRB 230903A: VLT/X-shooter optical observations
  70. GRB 230904C: Fermi GBM Final Localization
  71. GRB 230903A: Fermi GBM detection
  72. GRB 230904A: Fermi GBM Final Real-time Localization
  73. GRB 230903A: LCOGT Optical Upper Limits
  74. GRB 230903A: Swift detection of a burst
  75. GRB 230903A: Fermi GBM Final Real-time Localization
  76. GRB 230827B: Glowbug gamma-ray detection
  77. GRB 230827A: Glowbug gamma-ray detection
  78. GRB 230826A: Glowbug gamma-ray detection
  79. GRB 230827B: Swift-XRT afterglow detection
  80. LIGO/Virgo/KAGRA S230830b: Retraction of GW compact binary merger candidate
  81. GRB 230812B: Spectroscopic detection of the associated SN 2023pel.
  82. GRB 230827B: Swift ToO observations
  83. GRB 230827B: CALET Gamma-Ray Burst Monitor detection
  84. GRB 230828A: AstroSat CZTI detection
  85. GRB 230828A: GRBAlpha detection
  86. GRB 230827A: VZLUSAT-2 detection
  87. GRB 230827A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  88. GRB 230826A: VZLUSAT-2 detection
  89. GRB 230827B: VZLUSAT-2 detection
  90. GRB 230827B / GRB 230827256: Fermi GBM Observation
  91. GRB 230827A: GRBAlpha detection
  92. Subject: GRB230826A: Swift/UVOT upper limits
  93. GRB 230827.256 : GIT optical follow-up of ZTF23abaanxz/AT2023qxj
  94. GRB 230827A: Fermi GBM Final Real-time Localization
  95. AT 2023qxj: ZTF discovery of the likely afterglow of Fermi GRB 230827256
  96. GRB 230826A: GRBAlpha detection
  97. GRB 230826A: Enhanced Swift-XRT position
  98. GRB 230826A: Swift-XRT refined Analysis
  99. GRB 230826A: Mondy optical observations
  100. GRB 230826A: Swift detection of a burst

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