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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"

19662 results found.

  1. MAXI GRB 141029A is likely an X-ray flare from 1RXS J043657.1-161258
  2. GRB 141031B: Swift-XRT refined Analysis
  3. GRB 141031B: Bassano Bresciano Observatory upper limit
  4. GRB 141031B: Swift-BAT refined analysis
  5. GRB 141031A, Swift-BAT refined analysis
  6. GRB 141031B: Enhanced Swift-XRT position
  7. GRB 141031A: Swift/UVOT Upper Limits
  8. GRB 141031A: Swift-XRT refined Analysis
  9. GRB 141031A: Skynet PROMPT-CTIO Observations
  10. GRB 141031A: Fermi GBM detection
  11. GRB 141031B: MASTER early optical observations
  12. GRB 141031B: Swift detection of a burst
  13. GRB 141031A: Enhanced Swift-XRT position
  14. GRB 141031A: GROND detection of a possible optical afterglow candidate
  15. GRB 141031A: Swift detection of a burst
  16. GRB 140509A: GROND afterglow detection
  17. GRB 141028A: Swift/UVOT followup observations
  18. GRB 141028A: Swift-XRT observations
  19. GRB 141029A Tiled Swift observations
  20. GRB 141028A: Swift/UVOT Detection
  21. GRB 141028A: Swift/XRT detection of the X-ray afterglow
  22. GRB 141020A: Continued Mondy Observations, optical upper limit
  23. GRB 141026A: IRAM 30m millimetre observations
  24. GRB 141028A Tiled Swift observations
  25. GRB 141026A: Continued RATIR Optical and NIR Observations
  26. GRB 141028A: Fermi-LAT detection
  27. GRB 141026A: Skynet PROMPT-CTIO/Yerkes-41 Observations
  28. GRB 141026A: Swift/UVOT Upper Limits
  29. GRB 141026A: Swift-XRT refined Analysis
  30. GRB 141026A: Swift-BAT refined analysis
  31. GRB 141026A: MASTER early optical observations
  32. GRB 141026A: Enhanced Swift-XRT position
  33. GRB 141026A: GROND observations
  34. GRB 141026A: RATIR Optical Observations
  35. GRB 141026A: P60 early observations
  36. GRB 141026A: Swift detection of a burst
  37. GRB 141020A: AAO optical upper limit
  38. GRB 141020A: Khureltogot optical upper limit
  39. GRB141022A: Fermi GBM Detection
  40. GRB 141022A: Swift/UVOT Upper Limits
  41. GRB 141020A: Mondy optical observations
  42. GRB 141022A: Swift-BAT refined analysis
  43. GRB 141022A: Swift-XRT refined Analysis
  44. GRB141015A iTelescope observation
  45. GRB 141022A: GROND Detection of a possible Optical Afterglow Candidate
  46. GRB 141022A: Swift detection of a burst
  47. GRB 141004A: RATIR Late Time Optical and NIR Observations
  48. GRB 141020A: Swift-BAT refined analysis
  49. GRB 141020A: Swift-XRT refined Analysis
  50. GRB 141020A: 1.4 GHZ observation
  51. GRB 141020A: Swift/UVOT Detection
  52. GRB 141020A: Enhanced Swift-XRT position
  53. GRB 141020B: MAXI/GSC detection
  54. Konus-Wind observation of GRB 141017A
  55. GRB 141020A: Swift detection of a burst with an optical counterpart
  56. GRB 141017A, Swift-BAT refined analysis
  57. GRB 141017A: GROND Afterglow Confirmation
  58. GRB 141015A: Swift-XRT afterglow confirmation and refined Analysis
  59. GRB 141017A: Swift/UVOT Detection
  60. GRB 141017A: Swift-XRT refined Analysis
  61. GRB 141017A: Enhanced Swift-XRT position
  62. GRB 141017A: Zadko observatory - Gingin optical observations
  63. GRB 141017A: Swift detection of a burst
  64. GRB 141015A: Swift/UVOT Upper Limits
  65. GRB 141015A: Swift-BAT refined analysis
  66. GRB 141015A: RATIR Optical Upper Limits
  67. GRB 141015A: Enhanced Swift-XRT position
  68. GRB 141015A: Super-LOTIS early observations
  69. GRB 141015A: ISON-NM early optical observations
  70. GRB 141015A: Swift/XRT localization
  71. GRB 141015A: Swift detection of a burst
  72. IPN Triangulation of GRB 141011A (short/hard)
  73. Trigger 614903: Swift detection of IGR J17544-2619
  74. GRB 141005A: iTelescope.Net T21 Optical Observation
  75. GRB 141005A: Additional P60 imaging and afterglow confirmation
  76. GRB 141004A: Fermi GBM observation
  77. GRB 141004A: GROND observations
  78. GRB 141005A: GROND observations
  79. Konus-Wind observation of GRB 141005A
  80. GRB 141004A: Swift-XRT refined Analysis
  81. GRB 141005A: Swift-XRT refined Analysis
  82. GRB 141005A: Swift/UVOT Upper Limits
  83. GRB 141005A: Swift-BAT refined analysis
  84. GRB 141004A: Swift-BAT refined analysis
  85. GRB 141004A: Swift/UVOT Detection
  86. GRB 141005A: Fermi GBM Detection
  87. GRB 141005A: Enhanced Swift-XRT position
  88. GRB 141004A: RATIR Optical Observations
  89. GRB 141005A: P60 probable afterglow deteaction
  90. GRB 141004A: Enhanced Swift-XRT position
  91. GRB 141005A: Swift detection of a burst
  92. GRB 141004A: a long GRB detected by INTEGRAL
  93. GRB 141004A: Swift detection of a burst with an optical counterpart
  94. Swift observations of HD 305560
  95. GRB 140928A: Swift-XRT follow-up observations
  96. Swift possible detection of the Be star HD 305560
  97. GRB 140930B: Gemini South Spectroscopy
  98. GRB 140930B: GROND observations
  99. GRB 140930B Swift-BAT refined analysis
  100. GRB 140930B: Swift/UVOT Upper Limits

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