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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"

36188 results found.

  1. Fermi GRB 240605C: Global MASTER-Net observations report
  2. Fermi Gamma-ray Burst Monitor trigger 739290883/240605607 is not a GRB
  3. GRB 240605C: Fermi GBM Final Real-time Localization
  4. IPN triangulation of GRB 240603A
  5. GRB 240605B: Fermi GBM Final Real-time Localization
  6. GRB 240604A: Fermi GBM Final Localization
  7. GRB 240605A: Fermi GBM Final Real-time Localization
  8. GRB 240604A: GECAM detection of a long burst
  9. GRB 240529A: SAO RAS optical observations
  10. Swift Trigger 1232755: likely consistent with noise and not astrophysical
  11. Fermi GRB 240603C: Global MASTER-Net observations report
  12. LIGO/Virgo/KAGRA S240601co: Upper limits from Swift/BAT-GUANO
  13. LIGO/Virgo/KAGRA S240530a: Upper limits from Swift/BAT-GUANO
  14. GRB 240603A: Fermi GBM Final Localization
  15. GRB 240603C: BALROG localization (Fermi Trigger 739102156 / GRB 240603423)
  16. GRB 240603C: Fermi GBM Final Real-time Localization
  17. GRB 240603B: Swift detection of a possible burst
  18. GRB 240529A: MASTER prompt OT detection
  19. GRB 240603A: GECAM detection of a short burst
  20. GRB 240529A: continued SAO RAS optical observations
  21. Fermi GRB 240602A: Global MASTER-Net observations report
  22. GRB 240529A: OSN optical detection
  23. GRB 240529A: further SAO RAS optical observations
  24. GRB 240602A: Fermi GBM Final Real-time Localization
  25. Swift Trigger 1232465 is not a GRB
  26. GRB 240529A: AKO Optical Afterglow Follow-Up Observations
  27. GRB 240529A: 1.3m DFOT Optical observations
  28. GRB 240531A: AstroSat CZTI detection of a short burst
  29. GRB 240529A : Mondy optical observations
  30. Konus-Wind detection of GRB 240529A
  31. IPN triangulation of the initial episode of GRB 240529A
  32. GRB 240529A: SAO RAS optical observations
  33. GRB 240529A: MAAO 0.7m telescope optical afterglow detection
  34. GRB 240529A: Insight-HXMT/HE detection
  35. GRB 240529A: optical photometry from Konkoly
  36. GRB 240529A: GROWTH-India optical follow-up
  37. GRB 240529A: T193/MISTRAL observations
  38. GRB 240529A: Redshift from GTC/OSIRIS+
  39. GRB 240529A: AKO Optical Afterglow Detection
  40. LIGO/Virgo/KAGRA S240527fv: Upper limits from Swift/BAT-GUANO
  41. LIGO/Virgo/KAGRA S240525p: Upper limits from Swift/BAT-GUANO
  42. GRB 240529A: J-band detections with WINTER
  43. GRB 240529A: Skynet Optical Observations
  44. GRB 240529A: Swift-BAT refined analysis
  45. GRB 240529A: Swift-XRT refined Analysis
  46. GRB240529A: BOOTES-6/DPRT optical detection
  47. GRB 240529A: Swift/UVOT Detection
  48. GRB 240529A: NOT optical observations
  49. GRB 240529A: AstroSat CZTI detection
  50. GRB 240529A: GOTO optical afterglow detection
  51. GRB 240527B: Swift-XRT afterglow detection
  52. GRB 240529A: Enhanced Swift-XRT position
  53. GRB 240529A: Swift detection of a burst with an optical counterpart
  54. GRB 240527B: Fermi GBM Observation
  55. Fermi GRB 240527A: Global MASTER-Net observations report
  56. GRB 240527B: Fermi-LAT detection
  57. Fermi GRB 240527B: Global MASTER-Net observations report
  58. GRB 240527B: Fermi GBM Final Localization
  59. GRB 240527B: BALROG localization (Fermi Trigger 738511436 / GRB 240527586)
  60. GRB 240527A: Fermi GBM Final Real-time Localization
  61. GRB 240523A: Swift-BAT refined analysis
  62. GRB 240523A: Swift-XRT refined Analysis
  63. GRB 240523A: Enhanced Swift-XRT position
  64. GRB 240523A: Swift detection of a burst
  65. GRB 240521B: Fermi GBM Observation
  66. Fermi GBM Sub-Threshold Detection of GRB 240516B
  67. GRB 240513A: Swift-XRT afterglow detection
  68. GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
  69. GRB 240521A: GECAM-B detection of a long burst
  70. GRB 240516B: AstroSat CZTI detection
  71. LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
  72. LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
  73. LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
  74. GRB 240514B: VZLUSAT-2 detection
  75. GRB 240504A: VZLUSAT-2 detection
  76. GRB 240502A: VZLUSAT-2 detection
  77. GRB 240519A: GRBAlpha detection
  78. GRB 240516A: Swift/UVOT Upper Limits
  79. GRB 240519A: AstroSat CZTI detection
  80. GRB 240519A: BALROG localization (Fermi Trigger 737788024 / GRB 240519213)
  81. GRB 240516A: Swift-BAT refined analysis
  82. Fermi GRB 240517A: Global MASTER-Net observations report
  83. GRB 240516A ATCA radio observations
  84. IPN triangulation of GRB 240514B (short)
  85. GRB 240513A: Swift ToO observations
  86. GRB 240517A: Fermi GBM Final Real-time Localization
  87. Konus-Wind detection of GRB 240513A
  88. GRB 240516A: AstroSat CZTI detection
  89. GRB 240516A: Swift-XRT refined Analysis
  90. GRB 240514E: A possible candidate BD-21 1074
  91. GRB 240516A: Fermi GBM Observation
  92. GRB 240511A: Observations from GTC/OSIRIS+
  93. GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
  94. GRB 240516A: GOTO optical upper limit
  95. LIGO/Virgo/KAGRA S240422ed: GRID non-detection and upper limits
  96. GRB 240516A: Swift detection of a burst
  97. GRB 240514B: AT2024ixa/GOTO24bph is not consistent with the Fermi localisation
  98. GRB 240511A: radio detection of afterglow candidate
  99. GRB 240514B: GOTO candidate optical counterpart
  100. Fermi Gamma-ray Burst Monitor list of triggers that are not a GRB

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