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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"

27294 results found.

  1. GRB 190109B: Swift/UVOT Upper Limits
  2. GRB 190109A: Swift/UVOT Upper Limits
  3. GRB 190109B: Swift-XRT refined Analysis
  4. GRB 190106A: Liverpool Telescope observations
  5. GRB 190109B: Swift-BAT refined analysis
  6. GRB 190109A: Fermi GBM observation
  7. GRB 190109B: COATLI Optical Observations
  8. GRB 190109B: BOOTES-5/JGT optical observations
  9. GRB 190109B: Mondy optical upper limit
  10. GRB 190109A: Swift-BAT refined analysis
  11. GRB 190109B: Swift-XRT observations
  12. INTEGRAL Weak#8189: AROMA-N Optical Observation
  13. GRB 190109B: Swift detection of a burst
  14. CALET Gamma-Ray Burst Monitor: Policy change in the GCN circulars
  15. GRB 190109A: Swift-XRT refined Analysis
  16. GRB 190109A: Swift detection of a burst
  17. GRB 190106A: Mondy optical observations
  18. Trigger 882561: Swift detection of MAXI J1631-479
  19. IERCOO/ICSP optical observation of GRB 190106A
  20. GRB 190106A: GMG photometry in the 2nd night
  21. GRB 190106A: Swift-XRT refined Analysis
  22. GRB 190103B: CALET Gamma-Ray Burst Monitor detection
  23. GRB 190106A: GMG spectral results
  24. GRB 190106A: BOOTES-4/MET optical observations
  25. GRB 190106A: Swift/UVOT Detection
  26. GRB 190106A: Swift-BAT refined analysis
  27. GRB 190106A: Bassano Bresciano Observatory optical detection
  28. Fermi GBM Observations of IceCube-190104A
  29. GRB 190106A: GMG detection
  30. GRB 190106A: MITSuME Akeno optical observation
  31. GRB 190106A: MASTER Amur OT detection
  32. GRB 190106A: Swift detection of a burst with an optical counterpart
  33. SWIFT GRB190106.57 Global MASTER-Net OT detection
  34. IceCube-190104A: MASTER optical observation
  35. GRB 190103A: AstroSat CZTI detection
  36. GRB 190103B: Bassano Bresciano observatory upper limit
  37. GRB 190103B: Swift-BAT refined analysis
  38. GRB 190103B: Swift-XRT refined Analysis
  39. GRB 190103B: Swift detection of a burst
  40. GRB 181231A: BOOTES-2/TELMA optical observations
  41. GRB 181231A: Fermi GBM detection
  42. GRB 181231A: Fermi-LAT detection
  43. GRB 181225A: further Swift-XRT observations
  44. GRB 181228A: possible NOT optical detection
  45. Fermi GBM trigger 567868083/181230547 is not a GRB
  46. GRB 181227A: CALET Gamma-Ray Burst Monitor detection
  47. GRB 181228A: Xinglong-2.16m optical upper limit
  48. FRB 181228: Global MASTER Net optical inspection
  49. GRB 181227A: Global MASTER Net oprtical inspection
  50. Swift Trigger 880127 is not a GRB
  51. GRB 181228A: Swift-XRT refined Analysis
  52. GRB 181228A: Swift-BAT refined analysis
  53. GRB 181222B: Swift follow-up observations of MASTER optical transient J204928.79+245744.0
  54. GRB 181228A: Swift/UVOT Upper Limits
  55. GRB 181228A: Fermi GBM observation
  56. IPN Triangulation of GRB 181227A (long)
  57. GRB 181228A: Global MASTER Net OT detection
  58. GRB 181225A: CALET Gamma-Ray Burst Monitor detection
  59. GRB 181225A: KAIT Follow-Up Observations with Upper Limit
  60. GRB 181228A: Swift detection of a burst
  61. GRB 181227A: Fermi GBM detection
  62. GRB 181225A: Insight-HXMT/HE detection
  63. GRB 181225A: Swift observations and X-ray candidate afterglow
  64. GRB 181225A: Global MASTER Net optical observations
  65. GRB 181225A: Fermi GBM detection
  66. GRB 181225A: Fermi-LAT Detection
  67. GRB 181222B: Global MASTER Net observations of short bright Fermi GRB
  68. IPN Triangulation of extremely bright short GRB 181222B
  69. GRB 181224A: Swift-BAT refined analysis
  70. GRB 181224A: Swift detection of a burst
  71. GRB 181222A: CALET Gamma-Ray Burst Monitor detection
  72. GRB 181222B: Global MASTER Net observations of the short bright Fermi GRB error box.
  73. GRB 181222B : Fermi GBM detection
  74. Trigger 878548: Swift detection of AX 1631.9-4752
  75. Swift Trigger 878504 is not astrophysical
  76. GRB 181222A: Fermi GBM observation
  77. GRB 181217A: Insight-HXMT/HE detection
  78. GRB 181213A: Swift/UVOT Observations
  79. GRB 181213A:Insight-HXMT/HE detection
  80. GRB 181212A:Insight-HXMT/HE detection
  81. GRB 181213A: HMM-0.5m, NEXT-0.6m, CNEOST-1m optical observations
  82. GRB 181213A: NOT optical observations
  83. GRB 181213A: Swift-XRT refined Analysis
  84. IPN Triangulation of GRB 181212A (long)
  85. GRB 181213A: Swift-BAT refined analysis
  86. GRB181213A: Swift/UVOT Detection
  87. GRB 181213A: Swift-XRT observations
  88. GRB 181213A: BOOTES-5/JGT optical observations
  89. SWIFT GRB181213A Global MASTER-Net bright OT discovery
  90. GRB 181213A: Swift detection of a burst
  91. GRB 181212A: Fermi GBM Detection
  92. GRB 181126B: KAIT Follow-Up Observations of a Fermi Short GRB (Trigger 564897175)
  93. MASTER OT J063515.49-624002.9 of Fermi trigger 565936249: optical observations in SAAO
  94. MASTER: OTs detection during Fermi alert trigger 565936249 early observations
  95. GRB 181203A: GROND detection of the afterglow
  96. GRB 181126B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 564897175)
  97. GRB 181203A: BOOTES-3/YA optical observations
  98. Swift Trigger 874754 is likely not an astrophysical event
  99. GRB 181203A: Swift/UVOT Upper Limits
  100. GRB 181201A: Continued GROND observations show that afterglow is still bright

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