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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 141109A: Swift-BAT refined analysis
  2. GRB 141109A: Enhanced Swift-XRT position
  3. GRB 141109A: CQUEAN Detection at 0.85 - 1.05 micron
  4. GRB 141109A: GROND afterglow observation
  5. X-shooter redshift of GRB 141109A
  6. GRB 141109A: REM NIR candidate afterglow
  7. GRB 141109B: Swift detection of a burst
  8. GRB 141109A: Swift detection of a burst
  9. GRB 141104A: Swift-XRT observations
  10. GRB 141028A: Mondy optical observations
  11. GRB 141104A Tiled Swift observations
  12. GRB 141026A: CrAO optical observation
  13. GRB
  14. GRB 141026A: Gemini-North optical and NIR imaging
  15. GRB 141028A: TShAO optical observation
  16. GRB 141031B: TShAO optical observations
  17. GRB 141017A: Skynet PROMPT-CTIO/SSO Observations
  18. Konus-Wind observation of GRB 141104A
  19. IPN Triangulation of GRB 141104A (long/very bright)
  20. GRB 141102A possible precursor was another, known source
  21. Konus-Wind observation of GRB 141102A
  22. GRB 141022A: Skynet PROMPT-CTIO Observations
  23. GRB 141102A: Fermi-LAT detection
  24. GRB 141102A: Fermi GBM detection
  25. GRB 141102A found in ground analysis of BAT data
  26. GRB 141026A: VLA observations
  27. GRB 141031B: RATIR Optical and NIR Observation
  28. GRB 141031B: Swift/UVOT Upper Limits
  29. MAXI GRB 141029A is likely an X-ray flare from 1RXS J043657.1-161258
  30. GRB 141031B: Swift-XRT refined Analysis
  31. GRB 141031B: Bassano Bresciano Observatory upper limit
  32. GRB 141031B: NOT optical observations
  33. GRB 141031B: MITSuME Ishigakijima upper limits
  34. GRB 141031B: Swift-BAT refined analysis
  35. GRB 141031A, Swift-BAT refined analysis
  36. GRB 141031B: Enhanced Swift-XRT position
  37. GRB 141031A: Swift/UVOT Upper Limits
  38. GRB 141031B: TShAO optical upper limit
  39. GRB 141031B: 1.23m CAHA I-band observations
  40. GRB 141031A: Swift-XRT refined Analysis
  41. GRB 141031A: Skynet PROMPT-CTIO Observations
  42. GRB 141004A: Continued Late Time RATIR Optical and NIR Observations
  43. GRB 141031A: VLT/X-shooter optical observations
  44. GRB 141031A: Fermi GBM detection
  45. GRB 141031B: Nanshan optical upper limit
  46. GRB 141031B: MASTER early optical observations
  47. GRB 141031B: Swift detection of a burst
  48. GRB 141031A: Enhanced Swift-XRT position
  49. GRB 141031A: GROND detection of a possible optical afterglow candidate
  50. GRB 141031A: Swift detection of a burst
  51. GRB 141029A: Nanshan optical upper limit
  52. GRB 141028A: SAO RAS Zeiss-1000 photometry
  53. GRB 140509A: GROND afterglow detection
  54. GRB 141028A: Continued RATIR Observations
  55. GRB 141028A: Swift/UVOT followup observations
  56. GRB 141028A: P60 Observations and Decay Index
  57. IPN triangulation of GRB 141029B
  58. GRB 141029B: Fermi GBM detection
  59. GRB 141028A: Swift-XRT observations
  60. GRB 141028A: LCOGTN observations
  61. GRB 141029A Tiled Swift observations
  62. GRB 141028A: VLT/X-shooter redshift of z=2.33
  63. GRB141028A: Gemini-North redshift
  64. GRB 141029A: MAXI/GSC detection
  65. GRB 141028A: RATIR Optical and NIR Observations
  66. GRB 141028A: Swift/UVOT Detection
  67. GRB 141028A: Swift/XRT detection of the X-ray afterglow
  68. GRB 141028A: GROND Afterglow confirmation (MASTER source)
  69. GRB 141020A: Continued Mondy Observations, optical upper limit
  70. IPN triangulation of GRB 141028A
  71. GRB 141026A: IRAM 30m millimetre observations
  72. GRB 141028A Tiled Swift observations
  73. GRB 141028A: MASTER OT candidate detection
  74. GRB 141028A: Fermi GBM detection
  75. GRB 141026A: Continued RATIR Optical and NIR Observations
  76. GRB 141028A: Fermi-LAT detection
  77. GRB 141026A: GTC spectroscopy
  78. GRB 141026A: Skynet PROMPT-CTIO/Yerkes-41 Observations
  79. GRB 141026A: SAO RAS Zeiss-1000 observations
  80. GRB 141026A: Continued RATIR Optical and NIR Observations
  81. GRB 141026A: Swift/UVOT Upper Limits
  82. GRB 141004A: Continued RATIR Late Time Optical and NIR Observations
  83. GRB 141026A: Continued RATIR Optical and NIR Observations, Afterglow Detection
  84. GRB 141026A: Swift-XRT refined Analysis
  85. GRB 141026A: Swift-BAT refined analysis
  86. Fermi Gamma-ray Burst Monitor trigger 141026452 is not a GRB
  87. GRB 141026A: MASTER early optical observations
  88. GRB 141026A: Enhanced Swift-XRT position
  89. GRB141026A: Deep P200 optical imaging
  90. GRB 141026A: 1.23m CAHA I-band observations
  91. GRB 141026A: GROND observations
  92. GRB 141026A: RATIR Optical Observations
  93. GRB 141026A: P60 early observations
  94. GRB 141026A: Swift detection of a burst
  95. Fermi Gamma-ray Burst Monitor trigger 141025734 is not a GRB
  96. GRB 141020A: AAO optical upper limit
  97. GRB 141020A: Khureltogot optical upper limit
  98. GRB141022A: Fermi GBM Detection
  99. GRB141022B: Fermi GBM Detection
  100. GRB 141022A: Swift/UVOT Upper Limits

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