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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"
  1. GRB 141205A: Swift/UVOT Upper Limits
  2. GRB 141205A: Fermi GBM detection
  3. GRB 141205A: Nanshan optical upper limit
  4. GRB 141205A: XRT observations
  5. GRB 141205A Swift-BAT refined analysis
  6. GRB 141202A: Swift/UVOT Detection of a Variable Source Near the IPN Error Box
  7. GRB 141121A: Mondy optical observations
  8. GRB 141205A Short hard GRB found in ground analysis of BAT data
  9. Konus-Wind observation of GRB 141202A
  10. GRB 141130A: Mondy optical observations
  11. GRB 141202A: Swift XRT observations
  12. GRB 141202A: Fermi GBM Detection
  13. GRB 141202A Tiled Swift observations
  14. IPN Triangulation of GRB 141202A (short/hard)
  15. GRB 141130A: Mondy optical light curve
  16. GRB 141030A: Nanshan very early optical observations
  17. GRB 141121A: Continued RATIR Optical Observations
  18. GRB 141130A: Swift-BAT refined analysis
  19. GRB 141130A: Swift/UVOT Detection
  20. GRB 141130A: Swift-XRT refined Analysis
  21. GRB 141121A: VLA radio detection
  22. GRB 141130A: Enhanced Swift-XRT position
  23. GRB 141130A: Nanshan optical observations
  24. GRB 141130A: Mondy optical observations
  25. GRB 141130A: Swift detection of a burst with an optical counterpart
  26. GRB 141121A: Continued RATIR Optical Observations
  27. GRB 141121A: Mondy optical observations
  28. GRB 141121A: TSHAO optical observations
  29. GRB 141121A: Continued RATIR Optical Observations
  30. GRB 141121A: RATIR Optical Observations - Errata for GCN 17105
  31. GRB 141121A: MITSuME Ishigakijima Optical Observation after 7 days
  32. GRB 141121A: Khureltogot optical observations
  33. IPN Triangulation of GRB 141121A (initial episode)
  34. GRB 141121A: Mondy optical observations
  35. GRB 141121A: SPI-ACS/INTEGRAL observations
  36. GRB 141121A: RATIR Optical and NIR Observations
  37. Konus-Wind observation of GRB 141121A
  38. IPN Triangulation of GRB 141125A (short/hard)
  39. GRB 141121A: three epochs of SAO RAS optical observations
  40. GRB 141121A: Continued RATIR Optical Observations
  41. GRB 141121A: WSRT radio detection
  42. GRB 141121A: TSHAO optical observations
  43. GRB 141121A: Continued Mondy optical observations
  44. GRB 141121A: Continued RATIR Optical Observations
  45. GRB 141121A: RATIR Optical Observations - Steeper Fading
  46. GRB 141121A: AMI 15 GHz detection
  47. GRB 141121A: MITSuME Ishigakijima Optical Observation after 3 days
  48. GRB 141124A​: iPTF upper limits​
  49. GRB 141121A: RATIR Optical Observations - Fading Again
  50. GRB141124A: MASTER Detection of New Flare of QSO NVSS J075043+790917 During the Fermi Error Box inspection
  51. GRB 141118A: Fermi GBM Detection
  52. GRB 141121A: Mondy optical observations
  53. GRB 141121A: LCO-FTN rebrightening confirmation
  54. GRB 141121A: MITSuME Ishigakijima Optical Observation
  55. GRB 141121A: Continued RATIR Optical Observations - Rebrightening
  56. GRB 141121A: AAO optical observations
  57. GRB 141121A: MITSuME Akeno Optical observation
  58. GRB 141121A: Continued RATIR Optical Observations
  59. GRB 141121A: Swift-XRT refined Analysis
  60. GRB 141121A: Swift/UVOT Detections
  61. GRB 141121A: RATIR Optical Observations
  62. GRB 141121A: Swift-BAT refined analysis
  63. GRB 141121A: LCO-FTN observations
  64. GRB 141121A: Keck redshift
  65. GRB 141121A: Enhanced Swift-XRT position
  66. GRB 141118A: iPTF Optical Observations
  67. GRB 141121A: GROND Afterglow candidate
  68. GRB 141121A: MAXI/GSC detection
  69. GRB141121A: BOOTES-2/TELMA upper limit
  70. GRB 141121A: Swift detection of a burst
  71. Konus-Wind observation of GRB 141118A
  72. IPN Triangulation of GRB 141118A
  73. GRB 141109A: further VLA observations
  74. GRB 141104A: further Swift-XRT observations and afterglow candidate
  75. GRB 141109A: VLA detection
  76. Swift Trigger 618673: probable noise event
  77. Trigger 618634: Swift detection of Vela X-1
  78. GRB 141109B: optical upper limits
  79. GRB 141015A: TAROT La Silla observatory optical observations
  80. GRB 141022A: TAROT La Silla observatory optical observations
  81. GRB 141031A: TAROT La Silla observatory optical observations
  82. GRB 141109A: TAROT La Silla observatory optical observations
  83. GRB 141109A: AAO optical observations
  84. Swift Trigger 618402: probable noise event
  85. Swift Trigger 618391 is not an astrophysical event
  86. GRB 141109A: Terskol photometry
  87. GRB 141109B: Swift/UVOT Upper Limits
  88. GRB 141109A: Swift/UVOT Detection
  89. GRB 141109A: NOT r-band observation
  90. Konus-Wind observation of GRB 141109A
  91. GRB 141109B: MITSuME Akeno upper limits
  92. GRB141109A : Xinglong TNT optical observation
  93. GRB 141109B: IRAM 30m millimetre observations
  94. GRB 141109B: Swift-XRT refined Analysis
  95. Swift Trigger 618134 is not an astrophysical event
  96. GRB 141109A: MITSuME Ishigakijima upper limits
  97. GRB 141109A: Swift-XRT refined Analysis
  98. GRB 141109B: BOOTES-4 and TERSKOL optical upper limit
  99. GRB 141109B: Swift-BAT refined analysis
  100. GRB 141109B: Enhanced Swift-XRT position

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