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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"

45829 results found.

  1. GRB 141121A: Continued RATIR Optical Observations
  2. GRB 141121A: Mondy optical observations
  3. GRB 141121A: TSHAO optical observations
  4. GRB 141121A: Continued RATIR Optical Observations
  5. GRB 141121A: RATIR Optical Observations - Errata for GCN 17105
  6. GRB 141121A: MITSuME Ishigakijima Optical Observation after 7 days
  7. GRB 141121A: Khureltogot optical observations
  8. IPN Triangulation of GRB 141121A (initial episode)
  9. GRB 141121A: Mondy optical observations
  10. GRB 141121A: SPI-ACS/INTEGRAL observations
  11. GRB 141121A: RATIR Optical and NIR Observations
  12. Konus-Wind observation of GRB 141121A
  13. IPN Triangulation of GRB 141125A (short/hard)
  14. GRB 141121A: three epochs of SAO RAS optical observations
  15. GRB 141121A: Continued RATIR Optical Observations
  16. GRB 141121A: WSRT radio detection
  17. GRB 141121A: TSHAO optical observations
  18. GRB 141121A: Continued Mondy optical observations
  19. GRB 141121A: Continued RATIR Optical Observations
  20. GRB 141121A: RATIR Optical Observations - Steeper Fading
  21. GRB 141121A: AMI 15 GHz detection
  22. GRB 141121A: MITSuME Ishigakijima Optical Observation after 3 days
  23. GRB 141124A​: iPTF upper limits​
  24. GRB 141121A: RATIR Optical Observations - Fading Again
  25. GRB141124A: MASTER Detection of New Flare of QSO NVSS J075043+790917 During the Fermi Error Box inspection
  26. GRB 141118A: Fermi GBM Detection
  27. GRB 141121A: Mondy optical observations
  28. GRB 141121A: LCO-FTN rebrightening confirmation
  29. GRB 141121A: MITSuME Ishigakijima Optical Observation
  30. GRB 141121A: Continued RATIR Optical Observations - Rebrightening
  31. GRB 141121A: AAO optical observations
  32. GRB 141121A: MITSuME Akeno Optical observation
  33. GRB 141121A: Continued RATIR Optical Observations
  34. GRB 141121A: Swift-XRT refined Analysis
  35. GRB 141121A: Swift/UVOT Detections
  36. GRB 141121A: RATIR Optical Observations
  37. GRB 141121A: Swift-BAT refined analysis
  38. GRB 141121A: LCO-FTN observations
  39. GRB 141121A: Keck redshift
  40. GRB 141121A: Enhanced Swift-XRT position
  41. GRB 141118A: iPTF Optical Observations
  42. GRB 141121A: GROND Afterglow candidate
  43. GRB 141121A: MAXI/GSC detection
  44. GRB141121A: BOOTES-2/TELMA upper limit
  45. GRB 141121A: Swift detection of a burst
  46. Konus-Wind observation of GRB 141118A
  47. IPN Triangulation of GRB 141118A
  48. GRB 141109A: further VLA observations
  49. GRB 141104A: further Swift-XRT observations and afterglow candidate
  50. GRB 141109A: VLA detection
  51. Swift Trigger 618673: probable noise event
  52. Trigger 618634: Swift detection of Vela X-1
  53. GRB 141109B: optical upper limits
  54. GRB 141015A: TAROT La Silla observatory optical observations
  55. GRB 141022A: TAROT La Silla observatory optical observations
  56. GRB 141031A: TAROT La Silla observatory optical observations
  57. GRB 141109A: TAROT La Silla observatory optical observations
  58. GRB 141109A: AAO optical observations
  59. Swift Trigger 618402: probable noise event
  60. Swift Trigger 618391 is not an astrophysical event
  61. GRB 141109A: Terskol photometry
  62. GRB 141109B: Swift/UVOT Upper Limits
  63. GRB 141109A: Swift/UVOT Detection
  64. GRB 141109A: NOT r-band observation
  65. Konus-Wind observation of GRB 141109A
  66. GRB 141109B: MITSuME Akeno upper limits
  67. GRB141109A : Xinglong TNT optical observation
  68. GRB 141109B: IRAM 30m millimetre observations
  69. GRB 141109B: Swift-XRT refined Analysis
  70. Swift Trigger 618134 is not an astrophysical event
  71. GRB 141109A: MITSuME Ishigakijima upper limits
  72. GRB 141109A: Swift-XRT refined Analysis
  73. GRB 141109B: BOOTES-4 and TERSKOL optical upper limit
  74. GRB 141109B: Swift-BAT refined analysis
  75. GRB 141109B: Enhanced Swift-XRT position
  76. GRB 141109A: Swift-BAT refined analysis
  77. GRB 141109A: Enhanced Swift-XRT position
  78. GRB 141109A: CQUEAN Detection at 0.85 - 1.05 micron
  79. GRB 141109A: GROND afterglow observation
  80. X-shooter redshift of GRB 141109A
  81. GRB 141109A: REM NIR candidate afterglow
  82. GRB 141109B: Swift detection of a burst
  83. GRB 141109A: Swift detection of a burst
  84. GRB 141104A: Swift-XRT observations
  85. GRB 141028A: Mondy optical observations
  86. GRB 141104A Tiled Swift observations
  87. GRB 141026A: CrAO optical observation
  88. GRB
  89. GRB 141026A: Gemini-North optical and NIR imaging
  90. GRB 141028A: TShAO optical observation
  91. GRB 141031B: TShAO optical observations
  92. GRB 141017A: Skynet PROMPT-CTIO/SSO Observations
  93. Konus-Wind observation of GRB 141104A
  94. IPN Triangulation of GRB 141104A (long/very bright)
  95. GRB 141102A possible precursor was another, known source
  96. Konus-Wind observation of GRB 141102A
  97. GRB 141022A: Skynet PROMPT-CTIO Observations
  98. GRB 141102A: Fermi-LAT detection
  99. GRB 141102A: Fermi GBM detection
  100. GRB 141102A found in ground analysis of BAT data

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