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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

43604 results found.

  1. GRB 150213B: Swift detection of a burst with an optical afterglow
  2. GRB 150213A: Fermi GBM detection
  3. GRB 150212A: Swift-XRT refined Analysis
  4. GRB 150212A: RATIR Optical and NIR Observations
  5. GRB 150212A: Khureltogot optical upper limit
  6. GRB 150212A: Skynet DSO14/GORT observations
  7. GRB 150212A: Swift-BAT refined analysis
  8. GRB 150212A: MASTER optical observations
  9. GRB 150212A: No Swift/UVOT detection in initial observation
  10. GRB 150212A: P60 Afterglow Retraction
  11. GRB 150210A: Swift-XRT observations
  12. GRB 150212A: Swift-XRT afterglow detection
  13. GRB150212A: P60 Afterglow Candidate
  14. Konus-Wind observation of GRB 150211A
  15. GRB 150212A: Swift detection of a burst
  16. GRB 150211A iTelescope observation
  17. GRB 150210A: MASTER SN detection during LAT error box inspection
  18. GRB 150211A: Swift-BAT refined analysis
  19. GRB 150211A: Mondy optical upper limit
  20. GRB 150211A: Swift-XRT refined Analysis
  21. GRB 150210A: Tiled Swift observations
  22. Konus-Wind observation of GRB 150210A
  23. IPN Triangulation of GRB 150210A
  24. GRB 150210A: Fermi-LAT detection
  25. GRB 150211A: RATIR Optical and NIR Observations
  26. GRB 150211A: No afterglow detection in the Swift/UVOT initial observation
  27. GRB 150211A: Swift-XRT observations
  28. GRB 150211A: Swift detection of a burst
  29. GRB 150211A: MASTER early optical observations
  30. GRB 150210A: Fermi GBM detection
  31. GRB 150101B/ Swift J123205.1-105602: Second epoch Chandra observations
  32. GRB 150204A: GROND observations
  33. GRB 150202B: Swift/XRT afterglow confirmation
  34. GRB 150204A: Swift/XRT afterglow confirmation
  35. Konus-Wind observation of GRB 150206A
  36. GRB 150206A: Swift-BAT refined analysis
  37. GRB 150203A iTelescope observation
  38. GRB 150206A: Swift/UVOT Detection
  39. GRB 150206A: Swift-XRT refined Analysis
  40. Konus-Wind observation of GRB 150202B
  41. GRB 150206A: VLT/X-shooter redshift
  42. GRB 150206A: GROND afterglow observations
  43. GRB 150206A: Enhanced Swift-XRT position
  44. GRB 150206B: Fermi GBM detection
  45. Trigger 630047: Swift detection of 1RXS J180408.9-342058
  46. GRB 150206B: iPTF Optical Observations
  47. GRB 150206A: MAXI/GSC detection
  48. GRB 150206A: Swift detection of a burst with an optical afterglow
  49. GRB 150204A: LCOGT-Sutherland and Siding Springs observations
  50. GRB 150204A: Swift/UVOT Upper Limits
  51. GRB 150203A: Swift-BAT refined analysis
  52. GRB 150204A: Swift-XRT observations
  53. GRB 150204A: Fermi GBM detection
  54. GRB 150204A: Swift ToO observations
  55. GRB 150204A BAT refined analysis
  56. GRB 150202B: Swift XRT/UVOT observations
  57. GRB 150204A found in ground analysis of Swift-BAT data
  58. Swift Trigger 629693 was a noise event
  59. GRB 150202A, Swift-BAT refined analysis
  60. GRB 150203A: ISON-NM early optical limit
  61. IPN Triangulation of GRB 150202B
  62. GRB 150203A: Swift-XRT refined Analysis
  63. GRB 150202B: Tiled Swift observations
  64. Swift Trigger 629693: probably not real
  65. Fermi GBM trigger 150202624 is not a GRB
  66. GRB 150202A: Swift/UVOT Upper Limits
  67. GRB 150203A: REM optical and NIR observations
  68. GRB 150202A: Swift-XRT refined Analysis
  69. GRB 150203A: Fermi GBM observation
  70. GRB 150202B: Fermi GBM detection
  71. GRB 150203A: TAROT La Silla observatory optical observations
  72. GRB 150203A: GROND Upper limits
  73. GRB 150202B: Fermi-LAT detection
  74. GRB 150203A: Enhanced Swift-XRT position
  75. GRB 150203A: RATIR Optical and NIR Observations
  76. GRB 150202A: Enhanced Swift-XRT position
  77. GRB 150202A: GROND Upper limits
  78. GRB 150203A: P60 observations
  79. GRB 150203A: Prompt enhanced Swift-XRT position
  80. GRB 150203A: Swift detection of a burst
  81. GRB 150202A: Swift detection of a burst
  82. GRB 150201A, Swift-BAT refined analysis
  83. Konus-Wind observation of GRB 150201A
  84. GRB 150201A: GROND upper limits
  85. GRB 150201A: Swift-XRT refined Analysis
  86. GRB 150201A: Fermi GBM observation
  87. GRB 150201A: Enhanced Swift-XRT position
  88. GRB 150201A: Swift detection of a burst
  89. Swift Trigger 629206 is likely 1RXS J180408.9-342058
  90. GRB 150120B: Khureltogot optical observations
  91. GRB 150128A: MASTER OT detction during inspection
  92. GRB 150127B: Fermi GBM detection
  93. Konus-Wind observation of GRB 150127B
  94. GRB 150123A: MASTER inspection
  95. GRB 150120A: 9.8 GHz VLA upper limit
  96. IPN Triangulation of GRB 150127B
  97. IPN Triangulation of GRB 150127A
  98. GRB 150120A: Gemini-N imaging and host redshift
  99. Konus-Wind observation of GRB 150126A reveals its ultra-long nature
  100. GRB 150127A: Fermi-LAT detection

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