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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').

5468 results found.

  1. GRB 230204B: Fermi GBM detection
  2. GRB 230204B: Swift-XRT afterglow detection
  3. GRB 230205A: Swift-XRT refined Analysis
  4. GRB 230204B: GIT discovery of the likely optical afterglow
  5. GRB 230204A: Swift-XRT refined Analysis
  6. ZTF23aabmzlp/AT2023azs: Lulin 1m LOT optical observations
  7. Fermi-LAT gamma-ray observations of IceCube-230201A
  8. GRB 230129A: AstroSat CZTI detection
  9. GRB 230124A: Fermi GBM Observation
  10. Fermi-LAT gamma-ray observations of IceCube-230122A
  11. GRB 230123A: Swift-XRT refined Analysis
  12. GRB 230116C: Swift-XRT observations
  13. GRB 230116B: Fermi GBM observation
  14. GRB 230116D: 3.6m DOT optical upper limit
  15. GRB 230116D: SAO RAS further observations
  16. GRB 230116D: Swift-XRT refined Analysis
  17. GRB 230116D: GIT optical follow-up
  18. GRB 230116C: Swift detection of a burst
  19. Fermi-LAT gamma-ray observations of IceCube-230112A
  20. Fermi-LAT Gamma-ray Observations of IceCube-Cascade-230109A
  21. Fermi-LAT Gamma-ray Observations of IceCube-Cascade-221229A
  22. GRB 230111A: Fermi GBM Observation
  23. GRB 230102A: Fermi GBM Observation
  24. GRB 221231A: Fermi GBM Observation
  25. GRB 221231A: Swift-XRT afterglow detection
  26. GRB 221231A: Swift-XRT observations
  27. Fermi-LAT gamma-ray observations of IceCube-221229A
  28. GRB 221226A: Fermi GBM detection
  29. GRB 221226B: Fermi GBM Observation
  30. GRB 221226B: Swift-XRT refined Analysis
  31. Fermi-LAT gamma-ray observations of IceCube-221224A
  32. Fermi-LAT gamma-ray observations of IceCube-221223A
  33. GRB 221218A: 3.6m DOT optical upper limit
  34. GRB 221215A: Fermi GBM Detection
  35. Fermi-LAT gamma-ray observations of IceCube-221216A
  36. GRB 221216A: Fermi GBM observation
  37. GRB 221216A: Swift-XRT refined Analysis
  38. Fermi-LAT gamma-ray observations of IceCube-221210A
  39. GRB 221215A: Swift-XRT observations
  40. GRB 221209A: Fermi GBM observation
  41. GRB 221206B: Fermi GBM observation
  42. GRB 221206B: Swift-XRT observations
  43. GRB 221201A: Fermi GBM observation
  44. GRB 221202A: Swift-XRT refined Analysis
  45. GRB 221201A: Swift-XRT refined Analysis
  46. GRB 221126A: Fermi GBM observation
  47. Alert from the HAWC Burst Monitor HAWC-221128A
  48. Fermi-LAT gamma-ray observations of IceCube-221124A
  49. Alert from the HAWC Burst Monitor HAWC-221123A
  50. GRB 221120A: Fermi GBM observation
  51. GRB 221120A: Swift-XRT refined Analysis
  52. GRB 221120A: GIT upper limits on optical afterglow
  53. GRB 221119A: Fermi GBM detection
  54. GRB 221119A: Fermi-LAT detection
  55. GRB 221115A: Fermi GBM detection
  56. GRB 221110A: Swift-XRT refined Analysis
  57. GRB 221107A: Fermi GBM Observation
  58. GRB 221009A: Extended Bad Time Intervals for Fermi LAT data
  59. Fermi-LAT gamma-ray observations of IceCube-221104A
  60. GRB 221029A: Fermi GBM observation
  61. GRB 221028A: Swift-XRT refined Analysis
  62. GRB 221028A: 1.3m DFOT Optical upper limit
  63. GRB 221028A: HCT optical upper limit
  64. GRB 221028A: GIT optical upper limit
  65. GRB 221027B: Swift-XRT refined Analysis
  66. GRB 221027A: Fermi GBM detection
  67. GRB 221027A: Fermi-LAT detection
  68. GRB 221025A: Fermi GBM Observation
  69. GRB 221022A: Swift-XRT observations
  70. GRB 221024A: Swift-XRT refined Analysis
  71. GRB 221023A: Fermi GBM Observation
  72. GRB 221025A: Fermi-LAT detection
  73. GRB 221022A: Fermi GBM detection
  74. GRB 221023A: Fermi-LAT detection
  75. GRB 221022B: Fermi GBM detection
  76. GRB 221021A: Fermi GBM observation
  77. GRB 221017A: Swift-XRT observations
  78. GRB 221009A: Second epoch of NuSTAR data
  79. GRB 221016A: Swift-XRT refined Analysis
  80. GRB 221016A: Fermi GBM observation
  81. GRB 221009A: Armchair Energetics
  82. GRB 221009A: Fermi LAT data rate effects due to extremely high flux
  83. MAXI/GSC refined analysis of the bright X-ray afterglow of GRB 221009A/Swift J1913.1+1946
  84. GRB 221009A: IXPE preliminary upper limits of X-ray polarization
  85. GRB 221009A: Gamma-ray Detection by SIRI-2
  86. GRB 221006A: Swift-XRT afterglow detection
  87. GRB221009A: optical afterglow measurements from Konkoly Observatory
  88. GRB 221009A: NuSTAR Detection
  89. GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
  90. GRB 221009A: Upper limits from HAWC 8 hours after trigger
  91. GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
  92. GRB 221009A: Continued Swift/XRT observations
  93. Konus-Wind detection of GRB 221009A
  94. GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
  95. GRB 221009A: Fermi-LAT refined analysis
  96. GRB 221009A: Swift-XRT refined Analysis
  97. GRB 221009A or Swift J1913.1+1946: Fermi-LAT detection
  98. GRB 221008A: Swift-XRT observations
  99. GRB 221006A: Swift-XRT observations
  100. GRB 220930A: Swift-XRT refined Analysis

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