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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"

37364 results found.

  1. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  2. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  3. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  4. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  5. LIGO/Virgo/KAGRA S230922g: DECam GW-MMADS candidates
  6. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  7. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  8. GRB 230921A: Fermi GBM Final Real-time Localization
  9. GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova
  10. IPN triangulation of GRB 230919A (short)
  11. GRB 230919A: Fermi GBM Observation
  12. Fermi GBM Statement for Trigger 716527670/230916144
  13. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  14. GRB 230812B : optical observations from MISTRAL at Observatoire de Haute-Provence
  15. GRB 230919A: AstroSat CZTI detection
  16. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  17. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  18. GRB 230919A: Fermi GBM Final Real-time Localization
  19. Detection of self-absorbed radio emission from GRB 230812B with the JVLA + uGMRT
  20. GRB 230918B: Fermi GBM Final Real-time Localization
  21. GRB 230918A (short): Glowbug gamma-ray detection
  22. GRB 230916B: Glowbug gamma-ray detection
  23. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  24. GRB 230915A: Fermi GBM observation
  25. GRB 230812B: Radio observations with the uGMRT
  26. GRB 230918A: Fermi GBM Final Real-time Localization
  27. GRB 230917A: AstroSat CZTI detection
  28. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  29. GRB 230915B: Glowbug gamma-ray detection
  30. GRB 230916A: NuSTAR Discovery of Prompt Emission from a Potential GRB
  31. GRB 230911A: Fermi GBM Observation
  32. GRB 230915A: Swift/BAT-GUANO detection of a burst
  33. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  34. GRB 230911D: GRBAlpha detection
  35. Swift Trigger 1192233 is not a GRB
  36. GRB 230906A: optical counterpart
  37. GRB 230911A: Swift-XRT afterglow detection
  38. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  39. GRB 230913A: Glowbug gamma-ray detection
  40. GRB 230812B: Bad Time Intervals for Fermi GBM data
  41. GRB 230913A: Fermi GBM Observation
  42. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  43. Swift Trigger 1191904 is not a GRB
  44. GRB 230911A: Swift ToO observations
  45. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  46. Fermi GRB 230913A: Global MASTER-Net observations report
  47. GRB 230911A: GOTO optical counterpart candidate
  48. GRB 230913A: Fermi GBM Final Real-time Localization
  49. GRB 230908A: CALET Gamma-Ray Burst Monitor detection
  50. GRB 230911D: NuSTAR Detection of Prompt Emission
  51. GRB 230911B: AstroSat CZTI detection
  52. GRB 230911C: Swift-XRT refined Analysis
  53. GRB 230911C: Swift-BAT refined analysis
  54. GRB230911C: BOOTES-6/DPRT optical upper limit
  55. GRB 230906A: Chandra detection of the X-ray afterglow
  56. Swift GRB 230911C: Global MASTER-Net observations report
  57. GRB 230911D: Fermi GBM observation
  58. IPN triangulation of GRB 230911D (long)
  59. GRB 230911D: Fermi-LAT detection
  60. GRB230911C: LCOGT Optical Upper Limits
  61. GRB 230911C: Swift/UVOT Upper Limits
  62. GRB 230911B: GRBAlpha and VZLUSAT-2 joint detection
  63. GRB 230911C: GOTO optical upper limits
  64. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  65. GRB 230911B: correction to the KW GCN 34659
  66. Konus-Wind detection of GRB 230811D
  67. GRB 230911C: Enhanced Swift-XRT position
  68. GRB 230911D: BALROG localization (Fermi Trigger 716111594/ GRB 230911329)
  69. GRB 230911D: Fermi GBM Final Localization
  70. GRB 230911C: Swift detection of a burst
  71. Fermi GRB 230911B: Global MASTER-Net observations report
  72. GRB 230911B: Fermi GBM Final Real-time Localization
  73. GRB 230911A: Fermi GBM Final Real-time Localization
  74. GRB 230906A: BlackGEM upper limits
  75. GRB 230903A: TESS observations of optical emission
  76. GRB 230906A: AstroSat CZTI detection
  77. GRB 230910A: Fermi GBM Final Real-time Localization
  78. GRB 230908A: GRBAlpha detection
  79. GRB 230908A: AstroSat CZTI detection
  80. Glowbug gamma-ray detection GRB 230905B
  81. GRB 230906A: Swift/UVOT Upper Limits
  82. GRID detection of GRB 230827A
  83. GRB 230818A: radio observation with the VLA
  84. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  85. GRB 230906A: Swift-XRT observations
  86. Konus-Wind detection of GRB 230906A (short)
  87. IPN triangulation of GRB 230906A (short)
  88. GRB 230906A: Swift ToO observations
  89. GRB 230905B: AstroSat CZTI detection
  90. Fermi GRB 230906A: Global MASTER-Net observations report
  91. GRB 230812B: Chandra late-time detection of the X-ray afterglow
  92. GRB 230906A: Fermi GBM Final Localizationn
  93. GRB 230905B: GECAM-C detection of a long burst
  94. GRB 230905A: Fermi GBM Final Real-time Localization
  95. GRB 230903A: Swift-XRT refined Analysis
  96. GRB 230903A: Enhanced Swift-XRT position
  97. GRB 230903A: VLT/X-shooter optical observations
  98. GRB 230903A: Swift-BAT refined analysis
  99. GRB 230904C: Fermi GBM Final Localization
  100. Fermi GRB 230903A: Global MASTER-Net observations report

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