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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"

27298 results found.

  1. GRB 231017A: GOTO optical upper limits
  2. GRB 231017A: JinShan optical upper limit
  3. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  4. LIGO/Virgo/KAGRA S231018cb: One counterpart neutrino candidate event from an IceCube neutrino search
  5. GRB 231017A: Las Cumbres optical upper limit
  6. GRB 231017A: LCOGT Optical Upper Limits
  7. GRB231017A: GROWTH-India upper limits on the optical afterglow
  8. GRB 231018A: Fermi GBM Detection
  9. GRB 231017A: Fermi GBM Detection
  10. GRB 231012B may not be a GRB
  11. GRB 231018A: BALROG localization (Fermi Trigger / GRB 231018521)
  12. GRB 231018A: Fermi GBM Final Real-time Localization
  13. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  14. GRB231017A: Fermi GBM Final Localization
  15. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  16. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  17. GRB 231012A: Fermi GBM Final Real-time Localization
  18. GRB 231012A: Fermi GBM Final Real-time Localization
  19. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  20. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  21. GRB 231004A: Fermi GBM Final Real-time Localization
  22. GRB 231003A is not a GRB
  23. GRB 231003A: Fermi GBM Final Real-time Localization
  24. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  25. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  26. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  27. GRB 230827B: 10.4m GTC spectroscopic redshift
  28. GRB 230930A: Fermi GBM Final Real-time Localization
  29. AT2023sva / GRB230916B: GIT observations of the afterglow
  30. Swift Triggers 1192740, 1192742 and 1192743 are not astrophysical events
  31. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  32. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  33. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  34. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  35. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  36. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  37. LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
  38. GRB 230921A: Fermi GBM Final Real-time Localization
  39. IPN triangulation of GRB 230919A (short)
  40. GRB 230919A: Fermi GBM Observation
  41. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  42. Fermi GBM Statement for Trigger 716527670/230916144
  43. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  44. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  45. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  46. GRB 230919A: Fermi GBM Final Real-time Localization
  47. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  48. GRB 230918B: Fermi GBM Final Real-time Localization
  49. GRB 230916B: Glowbug gamma-ray detection
  50. AT 2023sva: NOT observations of the ZTF candidate afterglow
  51. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  52. GRB 230915A: Fermi GBM observation
  53. LIGO/Virgo/KAGRA S230918aq: Retraction of GW compact binary merger candidate
  54. GRB 230918A: Fermi GBM Final Real-time Localization
  55. Swift Triggers 1192480, 1192481, 1192482 and 1192483 are not astrophysical events
  56. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  57. GRB 230911A: Fermi GBM Observation
  58. Swift GRB230916.18: Global MASTER-Net observations report
  59. Fermi trigger No 716572242: Global MASTER-Net observations report
  60. Fermi trigger No 716544961: Global MASTER-Net observations report
  61. GRB 230915A: Swift/BAT-GUANO detection of a burst
  62. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  63. Swift GRB230916.19: Global MASTER-Net observations report
  64. Swift GRB230916.18: Global MASTER-Net observations report
  65. Swift Triggers 1192234, 1192235 and 1192236 are not astrophysical events
  66. Swift GRB230916.13: Global MASTER-Net observations report
  67. Swift GRB230916.12: Global MASTER-Net observations report
  68. Swift GRB230916.11: Global MASTER-Net observations report
  69. Swift Trigger 1192233 is not a GRB
  70. Fermi trigger No 716449174: Global MASTER-Net observations report
  71. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  72. IceCube Alert 230914.22: Global MASTER-Net observations report
  73. Swift Trigger 1192088 is not an astrophysical event
  74. Fermi trigger No 716419312: Global MASTER-Net observations report
  75. GRB 230812B: Bad Time Intervals for Fermi GBM data
  76. Swift Trigger 1191994 is not an astrophysical event
  77. Swift GRB230913.70: Global MASTER-Net observations report
  78. GRB 230913A: Fermi GBM Observation
  79. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  80. Swift Trigger 1191904 is not a GRB
  81. Swift GRB230913.70: Global MASTER-Net observations report
  82. Swift Trigger 1191903 is not an astrophysical event
  83. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  84. Fermi GRB 230913A: Global MASTER-Net observations report
  85. GRB 230911A: GOTO optical counterpart candidate
  86. GRB 230913A: Fermi GBM Final Real-time Localization
  87. GRB 230908A: CALET Gamma-Ray Burst Monitor detection
  88. GRB 230911D: NuSTAR Detection of Prompt Emission
  89. GRB 230911C: Swift-XRT refined Analysis
  90. GRB 230911C: Swift-BAT refined analysis
  91. GRB230911C: BOOTES-6/DPRT optical upper limit
  92. GRB 230906A: Chandra detection of the X-ray afterglow
  93. Swift GRB 230911C: Global MASTER-Net observations report
  94. GRB 230911D: Fermi GBM observation
  95. IPN triangulation of GRB 230911D (long)
  96. GRB 230911D: Fermi-LAT detection
  97. GRB230911C: LCOGT Optical Upper Limits
  98. GRB 230911C: Swift/UVOT Upper Limits
  99. Fermi trigger No 716145795: Global MASTER-Net observations report
  100. GRB 230911C: GOTO optical upper limits

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