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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"

27295 results found.

  1. GRB 190109B: Fermi GBM observation
  2. GRB 190109B: Swift/UVOT Upper Limits
  3. GRB 190109A: Swift/UVOT Upper Limits
  4. GRB 190109B: Swift-XRT refined Analysis
  5. GRB 190106A: Liverpool Telescope observations
  6. GRB 190109B: Swift-BAT refined analysis
  7. GRB 190109A: Fermi GBM observation
  8. GRB 190109B: COATLI Optical Observations
  9. GRB 190109B: BOOTES-5/JGT optical observations
  10. GRB 190109B: Mondy optical upper limit
  11. GRB 190109A: Swift-BAT refined analysis
  12. GRB 190109B: Swift-XRT observations
  13. INTEGRAL Weak#8189: AROMA-N Optical Observation
  14. GRB 190109B: Swift detection of a burst
  15. CALET Gamma-Ray Burst Monitor: Policy change in the GCN circulars
  16. GRB 190109A: Swift-XRT refined Analysis
  17. GRB 190109A: Swift detection of a burst
  18. GRB 190106A: Mondy optical observations
  19. Trigger 882561: Swift detection of MAXI J1631-479
  20. IERCOO/ICSP optical observation of GRB 190106A
  21. GRB 190106A: GMG photometry in the 2nd night
  22. GRB 190106A: Swift-XRT refined Analysis
  23. GRB 190103B: CALET Gamma-Ray Burst Monitor detection
  24. GRB 190106A: GMG spectral results
  25. GRB 190106A: BOOTES-4/MET optical observations
  26. GRB 190106A: Swift/UVOT Detection
  27. GRB 190106A: Swift-BAT refined analysis
  28. GRB 190106A: Bassano Bresciano Observatory optical detection
  29. Fermi GBM Observations of IceCube-190104A
  30. GRB 190106A: GMG detection
  31. GRB 190106A: MITSuME Akeno optical observation
  32. GRB 190106A: MASTER Amur OT detection
  33. GRB 190106A: Swift detection of a burst with an optical counterpart
  34. SWIFT GRB190106.57 Global MASTER-Net OT detection
  35. IceCube-190104A: MASTER optical observation
  36. GRB 190103A: AstroSat CZTI detection
  37. GRB 190103B: Bassano Bresciano observatory upper limit
  38. GRB 190103B: Swift-BAT refined analysis
  39. GRB 190103B: Swift-XRT refined Analysis
  40. GRB 190103B: Swift detection of a burst
  41. GRB 181231A: BOOTES-2/TELMA optical observations
  42. GRB 181231A: Fermi GBM detection
  43. GRB 181231A: Fermi-LAT detection
  44. GRB 181225A: further Swift-XRT observations
  45. GRB 181228A: possible NOT optical detection
  46. Fermi GBM trigger 567868083/181230547 is not a GRB
  47. GRB 181227A: CALET Gamma-Ray Burst Monitor detection
  48. GRB 181228A: Xinglong-2.16m optical upper limit
  49. FRB 181228: Global MASTER Net optical inspection
  50. GRB 181227A: Global MASTER Net oprtical inspection
  51. Swift Trigger 880127 is not a GRB
  52. GRB 181228A: Swift-XRT refined Analysis
  53. GRB 181228A: Swift-BAT refined analysis
  54. GRB 181222B: Swift follow-up observations of MASTER optical transient J204928.79+245744.0
  55. GRB 181228A: Swift/UVOT Upper Limits
  56. GRB 181228A: Fermi GBM observation
  57. IPN Triangulation of GRB 181227A (long)
  58. GRB 181228A: Global MASTER Net OT detection
  59. GRB 181225A: CALET Gamma-Ray Burst Monitor detection
  60. GRB 181225A: KAIT Follow-Up Observations with Upper Limit
  61. GRB 181228A: Swift detection of a burst
  62. GRB 181227A: Fermi GBM detection
  63. GRB 181225A: Insight-HXMT/HE detection
  64. GRB 181225A: Swift observations and X-ray candidate afterglow
  65. GRB 181225A: Global MASTER Net optical observations
  66. GRB 181225A: Fermi GBM detection
  67. GRB 181225A: Fermi-LAT Detection
  68. GRB 181222B: Global MASTER Net observations of short bright Fermi GRB
  69. IPN Triangulation of extremely bright short GRB 181222B
  70. GRB 181224A: Swift-BAT refined analysis
  71. GRB 181224A: Swift detection of a burst
  72. GRB 181222A: CALET Gamma-Ray Burst Monitor detection
  73. GRB 181222B: Global MASTER Net observations of the short bright Fermi GRB error box.
  74. GRB 181222B : Fermi GBM detection
  75. Trigger 878548: Swift detection of AX 1631.9-4752
  76. Swift Trigger 878504 is not astrophysical
  77. GRB 181222A: Fermi GBM observation
  78. GRB 181217A: Insight-HXMT/HE detection
  79. GRB 181213A: Swift/UVOT Observations
  80. GRB 181213A:Insight-HXMT/HE detection
  81. GRB 181212A:Insight-HXMT/HE detection
  82. GRB 181213A: HMM-0.5m, NEXT-0.6m, CNEOST-1m optical observations
  83. GRB 181213A: NOT optical observations
  84. GRB 181213A: Swift-XRT refined Analysis
  85. IPN Triangulation of GRB 181212A (long)
  86. GRB 181213A: Swift-BAT refined analysis
  87. GRB181213A: Swift/UVOT Detection
  88. GRB 181213A: Swift-XRT observations
  89. GRB 181213A: BOOTES-5/JGT optical observations
  90. SWIFT GRB181213A Global MASTER-Net bright OT discovery
  91. GRB 181213A: Swift detection of a burst
  92. GRB 181212A: Fermi GBM Detection
  93. GRB 181126B: KAIT Follow-Up Observations of a Fermi Short GRB (Trigger 564897175)
  94. MASTER OT J063515.49-624002.9 of Fermi trigger 565936249: optical observations in SAAO
  95. MASTER: OTs detection during Fermi alert trigger 565936249 early observations
  96. GRB 181203A: GROND detection of the afterglow
  97. GRB 181126B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 564897175)
  98. GRB 181203A: BOOTES-3/YA optical observations
  99. Swift Trigger 874754 is likely not an astrophysical event
  100. GRB 181203A: Swift/UVOT Upper Limits

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