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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"

27301 results found.

  1. IPN triangulation of GRB 231018A
  2. GRB 231017A: Swift/UVOT Upper Limit
  3. GRB 231019A: Fermi GBM Final Real-time Localization
  4. GRB 231017A: GOTO optical upper limits
  5. GRB 231017A: JinShan optical upper limit
  6. GRB 231018A: GROWTH-India Follow-Up of a Fermi Long GRB
  7. LIGO/Virgo/KAGRA S231018cb: One counterpart neutrino candidate event from an IceCube neutrino search
  8. GRB 231017A: Las Cumbres optical upper limit
  9. GRB 231017A: LCOGT Optical Upper Limits
  10. GRB231017A: GROWTH-India upper limits on the optical afterglow
  11. GRB 231018A: Fermi GBM Detection
  12. GRB 231017A: Fermi GBM Detection
  13. GRB 231012B may not be a GRB
  14. GRB 231018A: BALROG localization (Fermi Trigger / GRB 231018521)
  15. GRB 231018A: Fermi GBM Final Real-time Localization
  16. GRB 231017A: Swift/BAT-GUANO candidate arcminute localization of a burst
  17. GRB231017A: Fermi GBM Final Localization
  18. LIGO/Virgo/KAGRA S231014r: Upper limits from Swift/BAT-GUANO
  19. Correction in GCN 34814: GRB 231012B (not GRB 231012A)
  20. GRB 231012A: Fermi GBM Final Real-time Localization
  21. GRB 231012A: Fermi GBM Final Real-time Localization
  22. LIGO/Virgo/KAGRA S231005j: Upper limits from Swift/BAT-GUANO
  23. GRB 231004A: CALET Gamma-Ray Burst Monitor detection
  24. GRB 231004A: Fermi GBM Final Real-time Localization
  25. GRB 231003A is not a GRB
  26. GRB 231003A: Fermi GBM Final Real-time Localization
  27. LIGO/Virgo/KAGRA S231001aq: Upper limits from Swift/BAT-GUANO
  28. LIGO/Virgo/KAGRA S230930al: Upper limits from Swift/BAT-GUANO
  29. LIGO/Virgo/KAGRA S230928cb: Upper limits from Swift/BAT-GUANO
  30. GRB 230827B: 10.4m GTC spectroscopic redshift
  31. GRB 230930A: Fermi GBM Final Real-time Localization
  32. AT2023sva / GRB230916B: GIT observations of the afterglow
  33. Swift Triggers 1192740, 1192742 and 1192743 are not astrophysical events
  34. LIGO/Virgo/KAGRA S230924an: Upper limits from Swift/BAT-GUANO
  35. LIGO/Virgo/KAGRA S230920al: Upper limits from Swift/BAT-GUANO
  36. LIGO/Virgo/KAGRA S230919bj: Upper limits from Swift/BAT-GUANO
  37. Fermi Gamma-ray Burst Monitor trigger 717299390/230925076 is not a GRB
  38. Fermi Gamma-ray Burst Monitor trigger 230925241/717313591 is not a GRB
  39. LIGO/Virgo/KAGRA S230917af: GRAWITA wide-field observations
  40. LIGO/Virgo/KAGRA S230917af: Zwicky Transient Facility observations
  41. GRB 230921A: Fermi GBM Final Real-time Localization
  42. IPN triangulation of GRB 230919A (short)
  43. GRB 230919A: Fermi GBM Observation
  44. Correction to Fermi GBM Statement for Trigger 716527670/230916144
  45. Fermi GBM Statement for Trigger 716527670/230916144
  46. GRB 230919A: Swift/BAT-GUANO detection of a possibly short burst outside the coded FOV
  47. AT2023sva: redshift from OSIRIS+/GTC of the ZTF afterglow
  48. GRB 230918B: GOTO detection of a fast-rising transient in the GBM localisation region
  49. GRB 230919A: Fermi GBM Final Real-time Localization
  50. LIGO/Virgo S230917af: Swift XRT observations, 6 X-ray sources
  51. GRB 230918B: Fermi GBM Final Real-time Localization
  52. GRB 230916B: Glowbug gamma-ray detection
  53. AT 2023sva: NOT observations of the ZTF candidate afterglow
  54. ZTF and SEDM Observations of the Candidate Optical Afterglow AT 2023sva
  55. GRB 230915A: Fermi GBM observation
  56. LIGO/Virgo/KAGRA S230918aq: Retraction of GW compact binary merger candidate
  57. GRB 230918A: Fermi GBM Final Real-time Localization
  58. Swift Triggers 1192480, 1192481, 1192482 and 1192483 are not astrophysical events
  59. LIGO/Virgo/KAGRA S230917af: MAXI/GSC observations
  60. GRB 230911A: Fermi GBM Observation
  61. Swift GRB230916.18: Global MASTER-Net observations report
  62. Fermi trigger No 716572242: Global MASTER-Net observations report
  63. Fermi trigger No 716544961: Global MASTER-Net observations report
  64. GRB 230915A: Swift/BAT-GUANO detection of a burst
  65. LIGO/Virgo/KAGRA S230914ak: Upper limits from Swift/BAT-GUANO
  66. Swift GRB230916.19: Global MASTER-Net observations report
  67. Swift GRB230916.18: Global MASTER-Net observations report
  68. Swift Triggers 1192234, 1192235 and 1192236 are not astrophysical events
  69. Swift GRB230916.13: Global MASTER-Net observations report
  70. Swift GRB230916.12: Global MASTER-Net observations report
  71. Swift GRB230916.11: Global MASTER-Net observations report
  72. Swift Trigger 1192233 is not a GRB
  73. Fermi trigger No 716449174: Global MASTER-Net observations report
  74. GRB 230913A: CALET Gamma-Ray Burst Monitor detection
  75. IceCube Alert 230914.22: Global MASTER-Net observations report
  76. Swift Trigger 1192088 is not an astrophysical event
  77. Fermi trigger No 716419312: Global MASTER-Net observations report
  78. GRB 230812B: Bad Time Intervals for Fermi GBM data
  79. Swift Trigger 1191994 is not an astrophysical event
  80. Swift GRB230913.70: Global MASTER-Net observations report
  81. GRB 230913A: Fermi GBM Observation
  82. LIGO/Virgo/KAGRA S230904n: One ZTF candidate counterpart to coincident neutrino event
  83. Swift Trigger 1191904 is not a GRB
  84. Swift GRB230913.70: Global MASTER-Net observations report
  85. Swift Trigger 1191903 is not an astrophysical event
  86. GRB 230913A: Swift/BAT-GUANO arcminute localization of a burst
  87. Fermi GRB 230913A: Global MASTER-Net observations report
  88. GRB 230911A: GOTO optical counterpart candidate
  89. GRB 230913A: Fermi GBM Final Real-time Localization
  90. GRB 230908A: CALET Gamma-Ray Burst Monitor detection
  91. GRB 230911D: NuSTAR Detection of Prompt Emission
  92. GRB 230911C: Swift-XRT refined Analysis
  93. GRB 230911C: Swift-BAT refined analysis
  94. GRB230911C: BOOTES-6/DPRT optical upper limit
  95. GRB 230906A: Chandra detection of the X-ray afterglow
  96. Swift GRB 230911C: Global MASTER-Net observations report
  97. GRB 230911D: Fermi GBM observation
  98. IPN triangulation of GRB 230911D (long)
  99. GRB 230911D: Fermi-LAT detection
  100. GRB230911C: LCOGT Optical Upper Limits

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