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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

37766 results found.

  1. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  2. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  3. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  4. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  5. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  6. GRB 230812B: r'-band observations from MISTRAL at Observatoire de Haute-Provence
  7. GRB 230921A: Fermi GBM Final Real-time Localization
  8. GRB 230918B: VLT/X-shooter classification of AT 2023tbf (GOTO23aky) as a dwarf nova
  9. IPN triangulation of GRB 230919A (short)
  10. GRB 230919A: Fermi GBM Observation
  11. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  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. AT 2023sva: NOT observations of the ZTF candidate afterglow
  24. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  25. GRB 230915A: Fermi GBM observation
  26. GRB 230812B: Radio observations with the uGMRT
  27. GRB 230918A: Fermi GBM Final Real-time Localization
  28. GRB 230917A: AstroSat CZTI detection
  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. Fermi trigger No 716572242: Global MASTER-Net observations report
  33. Fermi trigger No 716544961: Global MASTER-Net observations report
  34. Fermi-LAT gamma-ray observations of IceCube-230914A
  35. GRB 230915A: Swift/BAT-GUANO detection of a burst
  36. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  37. GRB 230911D: GRBAlpha detection
  38. Swift Trigger 1192233 is not a GRB
  39. GRB 230906A: optical counterpart
  40. GRB 230911A: Swift-XRT afterglow detection
  41. Fermi trigger No 716449174: Global MASTER-Net observations report
  42. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  43. Fermi trigger No 716419312: Global MASTER-Net observations report
  44. GRB 230913A: Glowbug gamma-ray detection
  45. GRB 230812B: Bad Time Intervals for Fermi GBM data
  46. IceCube-230914A - IceCube observation of a high-energy neutrino candidate track-like event
  47. GRB 230913A: Fermi GBM Observation
  48. Swift Trigger 1191904 is not a GRB
  49. GRB 230911A: Swift ToO observations
  50. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  51. Fermi GRB 230913A: Global MASTER-Net observations report
  52. GRB 230911A: GOTO optical counterpart candidate
  53. GRB 230913A: Fermi GBM Final Real-time Localization
  54. GRB 230908A: CALET Gamma-Ray Burst Monitor detection
  55. GRB 230911D: NuSTAR Detection of Prompt Emission
  56. GRB 230911B: AstroSat CZTI detection
  57. GRB 230911C: Swift-XRT refined Analysis
  58. GRB 230911C: Swift-BAT refined analysis
  59. GRB230911C: BOOTES-6/DPRT optical upper limit
  60. GRB 230906A: Chandra detection of the X-ray afterglow
  61. Swift GRB 230911C: Global MASTER-Net observations report
  62. GRB 230911D: Fermi GBM observation
  63. IPN triangulation of GRB 230911D (long)
  64. GRB 230911D: Fermi-LAT detection
  65. GRB230911C: LCOGT Optical Upper Limits
  66. GRB 230911C: Swift/UVOT Upper Limits
  67. GRB 230911B: GRBAlpha and VZLUSAT-2 joint detection
  68. Fermi trigger No 716145795: Global MASTER-Net observations report
  69. GRB 230911C: GOTO optical upper limits
  70. GRB 230908A: Swift/BAT-GUANO detection of a long burst outside the coded FOV
  71. GRB 230911B: correction to the KW GCN 34659
  72. Konus-Wind detection of GRB 230811D
  73. GRB 230911C: Enhanced Swift-XRT position
  74. GRB 230911D: BALROG localization (Fermi Trigger 716111594/ GRB 230911329)
  75. GRB 230911D: Fermi GBM Final Localization
  76. GRB 230911C: Swift detection of a burst
  77. Fermi GRB 230911B: Global MASTER-Net observations report
  78. GRB 230911B: Fermi GBM Final Real-time Localization
  79. GRB 230911A: Fermi GBM Final Real-time Localization
  80. GRB 230906A: BlackGEM upper limits
  81. GRB 230903A: TESS observations of optical emission
  82. GRB 230906A: AstroSat CZTI detection
  83. GRB 230910A: Fermi GBM Final Real-time Localization
  84. GRB 230908A: GRBAlpha detection
  85. GRB 230908A: AstroSat CZTI detection
  86. Glowbug gamma-ray detection GRB 230905B
  87. GRB 230906A: Swift/UVOT Upper Limits
  88. GRID detection of GRB 230827A
  89. GRB 230818A: radio observation with the VLA
  90. GRB 230205A: LBT spectroscopy of two host galaxy candidates
  91. GRB 230906A: Swift-XRT observations
  92. Konus-Wind detection of GRB 230906A (short)
  93. IPN triangulation of GRB 230906A (short)
  94. GRB 230906A: Swift ToO observations
  95. GRB 230905B: AstroSat CZTI detection
  96. Fermi GRB 230906A: Global MASTER-Net observations report
  97. GRB 230812B: Chandra late-time detection of the X-ray afterglow
  98. GRB 230906A: Fermi GBM Final Localizationn
  99. GRB 230905B: GECAM-C detection of a long burst
  100. GRB 230905A: Fermi GBM Final Real-time Localization

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