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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"

6402 results found.

  1. GRB 140709A: Swift-XRT refined Analysis
  2. GRB 140706A: Swift-XRT refined Analysis
  3. GRB 140705A: Swift-XRT refined Analysis
  4. GRB 140629A: SAO RAS Rc band photometry
  5. GRB 140629A, Optical observations
  6. GRB 140703A: Fermi GBM detection
  7. GRB 140703A: Swift-XRT refined Analysis
  8. GRB 140629A: Nishi-Harima NIR Observations
  9. GRB 140629A: Swift-XRT refined Analysis
  10. GRB 140629A: T100 observations
  11. GRB 140629A: NOT optical observations
  12. GRB 140629A : Virtual Telescope optical observations
  13. GRB 140628A: Swift-XRT refined Analysis
  14. GRB 140628A: Swift/UVOT Detection
  15. Swift Trigger 602668: XRT and UVOT confirm is not astrophysical source
  16. GRB 140623A: further Swift-XRT observations
  17. GRB 140626A: Swift-XRT refined Analysis
  18. Further Swift/XRT observations of GRB140620A/iPTFcva
  19. GRB 140624A: Fermi GBM observation of a short burst
  20. GRB 140623A: Swift-XRT and UVOT observations
  21. GRB 140623A / iPTF14cyb: Fermi GBM detection
  22. GRB 140621A: Swift-XRT observations
  23. GRB 140621A: Fermi GBM detection
  24. GRB 140622A: Swift-XRT refined Analysis
  25. GRB 140620A: Swift/UVOT Detection
  26. GRB 140620A: Swift-XRT observations
  27. GRB 140620A / iPTF14cva: Fermi GBM observations
  28. GRB 140619B: Swift-XRT observations
  29. GRB 140619B: Fermi-LAT Detection
  30. GRB 140619B: Fermi GBM detection of a short GRB
  31. GRB 140619A: Swift-XRT refined Analysis
  32. GRB 140606B: Swift XRT final light curve
  33. GRB 140614B: MOSFIRE Ks-band nondetection
  34. GRB 140614B: Swift-XRT refined Analysis
  35. GRB 140614A: Swift-XRT refined Analysis
  36. GRB 140611A: Swift-XRT observations
  37. GRB 140610A: Swift-XRT refined Analysis
  38. GRB 140606B / iPTF 14bfu: MOSFIRE NIR imaging
  39. GRB 140610A: Fermi GBM Detection
  40. GRB 140606B: Swift XRT refined analysis
  41. GRB 140606B: Swift/UVOT Upper Limits
  42. GRB 140606B: Swift XRT position
  43. GRB 140606B: Fermi GBM detection
  44. GRB 140606A: Swift-XRT upper limits
  45. GRB 140523A: further Swift-XRT observations
  46. GRB 140528A: Fermi GBM Detection
  47. GRB 140529A: Swift-XRT afterglow detection.
  48. Chandra late-time observations of GRB140515A
  49. GRB 140523A: possible X-ray afterglow candidate from tiled Swift/XRT observations
  50. GRB 140523A: Fermi-LAT detection
  51. GRB 140523A: Fermi GBM detection
  52. GRB 140423A: TShAO optical observations
  53. GRB 140516A: further Swift-XRT analysis
  54. GRB 140518A: T100 observations
  55. GRB 140518A: Swift-XRT refined Analysis
  56. GRB 140516A: Swift-XRT refined Analysis
  57. GRB 140515A: Swift-XRT refined Analysis
  58. GRB 140423A: HCT optical observations
  59. GRB 140512A: Fermi GBM detection
  60. GRB 140512A: Swift-XRT refined Analysis
  61. Swift Observations of GRB 140508A
  62. GRB 140509A: Swift-XRT refined Analysis
  63. GRB 140508A: Optical Observations via Virtual Telescope
  64. GRB 140508A: Swift-XRT observations
  65. GRB 140508A: Fermi GBM detection
  66. GRB 140506A: Fermi GBM Detection
  67. GRB 140506A: Swift-XRT refined Analysis
  68. GRB 140502A: Swift-XRT refined Analysis
  69. GRB 140502A: Fermi GBM observation
  70. GRB 140501A: Fermi GBM detection
  71. GRB 140430A: Swift-XRT refined Analysis
  72. GRB 140428B: Fermi GBM observation
  73. GRB 140423A: RTT150 optical observations
  74. GRB 140423A: Nishi-Harima NIR Observations
  75. GRB 140423A, Optical Observations
  76. GRB 140423A: Swift-XRT refined Analysis
  77. GRB 140423A: Fermi GBM observation
  78. GRB 140423A: KWFC z-band photometry
  79. GRB 140419A: Continued RATIR Optical and NIR Observations
  80. GRB 140419A, Optical Observations
  81. GRB 140419A: Swift-XRT refined Analysis
  82. GRB 140419A: T24 optical observations
  83. GRB 140416A: Fermi GBM detection
  84. GRB 140414A: Swift/UVOT Upper Limit
  85. GRB 140414A: Swift-XRT observations
  86. GRB 140413A: Swift-XRT refined Analysis
  87. GRB 140412A: Swift-XRT refined Analysis
  88. Swift Trigger 595345 is not an astrophysical source
  89. GRB 140408A: Swift-XRT refined Analysis
  90. GRB 140408A: Fermi GBM detection
  91. GRB 140406A: Fermi GBM observation
  92. GRB 140402A: Swift-XRT observations
  93. GRB 140402A : Xinglong TNT upper limit
  94. GRB 140402A: Fermi GBM detection
  95. GRB 140402A: Fermi-LAT detection of a burst
  96. Swift trigger 594286: Is likely a noise trigger
  97. GRB 140330A: Fermi GBM observation
  98. GRB 140331A: Swift-XRT refined Analysis
  99. Retraction of the Fermi/LAT high-energy counterpart for GRB 140330A
  100. GRB 140330A: Fermi-LAT Detection

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