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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"

28222 results found.

  1. GRB 240602A: Fermi GBM Final Real-time Localization
  2. Swift Trigger 1232465 is not a GRB
  3. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  4. LXT 240528A: GSP optical upper limit
  5. GRB 240529A: 1.3m DFOT Optical observations
  6. GRB 240531A: AstroSat CZTI detection of a short burst
  7. GRB 240529A : Mondy optical observations
  8. Konus-Wind detection of GRB 240529A
  9. IPN triangulation of the initial episode of GRB 240529A
  10. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  11. GRB 240529A: Insight-HXMT/HE detection
  12. GRB 240529A: optical photometry from Konkoly
  13. GRB 240529A: GROWTH-India optical follow-up
  14. GRB 240529A: T193/MISTRAL observations
  15. GRB 240529A: Redshift from GTC/OSIRIS+
  16. GRB 240529A: AKO Optical Afterglow Detection
  17. LXT 240528A: LEIA detection of a fast X-ray transient
  18. GRB 240529A: Swift-XRT refined Analysis
  19. GRB240529A: BOOTES-6/DPRT optical detection
  20. GRB 240529A: Swift/UVOT Detection
  21. GRB 240529A: NOT optical observations
  22. GRB 240529A: AstroSat CZTI detection
  23. GRB 240529A: GOTO optical afterglow detection
  24. GRB 240527B: Swift-XRT afterglow detection
  25. GRB 240529A: Enhanced Swift-XRT position
  26. GRB 240529A: Swift detection of a burst with an optical counterpart
  27. GRB 240527B: Fermi-LAT detection
  28. GRB 240527B: Fermi GBM Final Localization
  29. GRB 240527A: Fermi GBM Final Real-time Localization
  30. GRB 240523A: Swift-XRT refined Analysis
  31. GRB 240523A: Enhanced Swift-XRT position
  32. GRB 240523A: Swift detection of a burst
  33. Fermi GBM Sub-Threshold Detection of GRB 240516B
  34. GRB 240513A: Swift-XRT afterglow detection
  35. EP240518a: GSP optical upper limit
  36. GRB 240521A: GECAM-B detection of a long burst
  37. GRB 240516B: AstroSat CZTI detection
  38. GRB 240514B: VZLUSAT-2 detection
  39. GRB 240504A: VZLUSAT-2 detection
  40. GRB 240502A: VZLUSAT-2 detection
  41. GRB 240519A: GRBAlpha detection
  42. GRB 240516A: Swift/UVOT Upper Limits
  43. GRB 240519A: AstroSat CZTI detection
  44. EP240518a: possibly identified with a flare star by EP-FXT
  45. EP240518a: EP-WXT detection of a new X-ray transient
  46. GRB 240516A ATCA radio observations
  47. IPN triangulation of GRB 240514B (short)
  48. GRB 240513A: Swift ToO observations
  49. GRB 240517A: Fermi GBM Final Real-time Localization
  50. Konus-Wind detection of GRB 240513A
  51. GRB 240516A: AstroSat CZTI detection
  52. GRB 240516A: Swift-XRT refined Analysis
  53. GRB 240514E: A possible candidate BD-21 1074
  54. GRB 240511A: Observations from GTC/OSIRIS+
  55. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  56. GRB 240516A: GOTO optical upper limit
  57. LIGO/Virgo/KAGRA S240422ed: GRID non-detection and upper limits
  58. GRB 240516A: Swift detection of a burst
  59. GRB 240511A: radio detection of afterglow candidate
  60. GRB 240514E: MAXI/GSC detection of a probable afterglow
  61. GRB 240514B: GRBAlpha detection
  62. GRB 240514B: Fermi GBM Detection
  63. GRB 240513A: Swift-XRT observations
  64. GRB 240514D: AstroSat CZTI detection
  65. GRB 240514C: Fermi GBM Final Real-time Localization
  66. transient: Xinglong Nearby Galaxy Supernova Survey detection of AT2024iss
  67. GRB 240514B: Fermi GBM Final Real-time Localization
  68. GRB 240514A: Fermi GBM Final Real-time Localization
  69. GRB 240513A: Tiled Swift observations
  70. GRB 240513A: Fermi-LAT detection
  71. GRB 240511A: Fermi GBM Observation
  72. GRB 240513B: Fermi GBM Final Real-time Localization
  73. GRB 240513A: AstroSat CZTI detection
  74. GRB 240511A: J-band observations with WINTER
  75. GRB 240511A: Enhanced Swift-XRT position
  76. GRB 240511A : MITSuME Akeno optical upper limits
  77. GRB 240511A: Swift-XRT refined Analysis
  78. GRB 240511A: optical afterglow detection from the NOT
  79. GRB 240511A: Prompt enhanced Swift-XRT position
  80. GRB 240511A: Swift detection of a burst
  81. GRB 240511A: Fermi GBM Final Real-time Localization
  82. EP240506a: Xinglong optical upper limit
  83. EP240506a: Archival radio searching
  84. EP240506a: BOOTES Network optical upper limit
  85. IPN triangulation of GRB 240504A
  86. GRB 240502A: 1.3m DFOT Optical upper limit
  87. EP240506a: EP-WXT detection of a new fast X-ray transient
  88. GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
  89. IPN triangulation of GRB 240501B and GRB 240501A - possible episodes of ultra long GRB
  90. GRB 240503A: AstroSat CZTI detection
  91. GRB 240504A: Fermi GBM Final Real-time Localization
  92. GRB 240415A 1.3m DFOT Optical upper limit
  93. GRB 240502C: GOTO possible optical counterpart candidates
  94. GRB 240502C: Fermi GBM Final Localization
  95. GRB 240501B: GRBAlpha detection
  96. GRB 240430A: GRBAlpha detection
  97. GRB 240502B: Fermi GBM Final Real-time Localization
  98. GRB 240502A: Fermi GBM Final Real-time Localization
  99. GRB 240426A: VZLUSAT-2 detection
  100. GRB 240425A: VZLUSAT-2 detection

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