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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"

3050 results found.

  1. GRB 150626A: Swift-XRT refined Analysis
  2. GRB 150622A: Swift-XRT observations
  3. GRB 150616A: Swift-XRT refined Analysis
  4. GRB 150615A: Swift-XRT refined Analysis
  5. GRB 150608A: Swift-XRT follow-up observations
  6. GRB 150608A: Swift-XRT afterglow detection
  7. GRB 150607A: Swift-XRT refined Analysis
  8. Swift trigger 642453 is not an astrophysical source
  9. GRB 150530B: Swift-XRT observations
  10. GRB 150530A: Swift-XRT refined Analysis
  11. GRB 150513A: Swift-XRT observations
  12. GRB 150527A: Swift-XRT refined Analysis
  13. GRB 150523A Swift-XRT afterglow detection
  14. GRB 150518A: Swift-XRT follow-up observations
  15. GRB 150518A: Swift-XRT afterglow detection
  16. GRB 150514A: Further Swift observations
  17. GRB 150514A: Swift-XRT afterglow detection
  18. Confirmation that Swift Trigger 639636 is not astrophysical
  19. GRB 150430A: Swift-XRT refined Analysis
  20. GRB 150428B: IRSF NIR upper limits
  21. GRB 150428B: Swift/UVOT Upper Limits
  22. GRB 150428C: Swift-XRT observations
  23. GRB 150428B: Swift-XRT refined Analysis
  24. GRB 150428A: Swift-XRT refined Analysis
  25. GRB 150424A: Swift-XRT refined Analysis
  26. GRB 150423A: Swift-XRT refined Analysis
  27. GRB 150423A: GROND afterglow candidate
  28. GRB150418A: Swift/UVOT did not detect a new source
  29. Further Swift XRT observations of GRB 150418A
  30. GRB 150413A: Swift-XRT observations
  31. GRB 150418A: Swift-XRT observations
  32. Confirmation that Swift trigger 638217 is not an astrophysical source
  33. Swift GRB150402A: further XRT observations
  34. GRB 150407A: Swift-XRT observations
  35. GRB 150403A: Swift-XRT refined Analysis
  36. GRB 150402A: results of Swift observations
  37. GRB 150323B: Swift-XRT afterglow detection
  38. GRB 150323C: Nishi-Harima NIR Observations
  39. GRB 150323B: Swift-XRT observations
  40. GRB 150323C: Swift-XRT refined Analysis
  41. GRB 150323A: Swift-XRT refined Analysis
  42. GRB 150318A: Swift-XRT refined Analysis
  43. GRB 150317A: Swift-XRT refined Analysis
  44. GRB 150314A: Swift-XRT refined Analysis
  45. GRB 150309A: Swift-XRT refined Analysis
  46. Chandra X-ray observations of SWIFT J0045.2+4151 (aka Sw J0045 aka GRB 150301C aka p[PFH2005] 622)
  47. Further UVOT Observations of Swift J0045.2+4151
  48. Further X-ray observations of Swift J0045.2+4151 (aka Sw J0045 aka GRB 150301C aka [PFH2005] 622)
  49. GRB 150301C: XRT detection of a potential counterpart of BAT trigger 633105
  50. GRB 150302A: Swift-XRT refined Analysis
  51. GRB 150301B: Swift-XRT refined Analysis
  52. GRB 150301A: Swift-XRT refined Analysis
  53. GRB 150301C : (Swift trigger 633105) Swift observations
  54. GRB 150220A: Swift-XRT observations
  55. GRB 150222A: Swift-XRT refined Analysis
  56. GRB 150219A: Swift-XRT afterglow detection
  57. GRB 150213B: Swift-XRT refined Analysis
  58. GRB 150212A: Swift-XRT refined Analysis
  59. GRB 150210A: Swift-XRT observations
  60. GRB 150211A: Swift-XRT refined Analysis
  61. GRB 150101B/ Swift J123205.1-105602: Second epoch Chandra observations
  62. GRB 150202B: Swift/XRT afterglow confirmation
  63. GRB 150204A: Swift/XRT afterglow confirmation
  64. GRB 150206A: Swift-XRT refined Analysis
  65. GRB 150204A: Swift-XRT observations
  66. GRB 150202B: Swift XRT/UVOT observations
  67. Swift Trigger 629693 was a noise event
  68. GRB 150203A: Swift-XRT refined Analysis
  69. GRB 150202A: Swift-XRT refined Analysis
  70. GRB 150201A: Swift-XRT refined Analysis
  71. Konus-Wind observation of GRB 150126A reveals its ultra-long nature
  72. GRB 150123A: Swift-XRT observations
  73. GRB 150120A: Swift-XRT refined Analysis
  74. GRB 150120B: Swift-XRT refined Analysis
  75. GRB 150101B/Swift J123205.1-105602: XMM-Newton observation
  76. GRB 150110C: Swift-XRT observations
  77. GRB 150110B: Swift-XRT refined Analysis
  78. GRB 150101B/Swift J123205.1-105602: Chandra observations
  79. GRB 150101B/Swift J123205.1-105602: VLT observations and redshift
  80. GRB 150103A: Swift-XRT refined Analysis
  81. GRB 150103A: Swift/UVOT Upper Limits
  82. Swift J123205.1-105602: XRT and UVOT observations of soft short burst source
  83. GRB 150101A: Swift-XRT refined Analysis
  84. Swift-XRT and UVOT follow-up of iPTF14jko (GRB 141230A)
  85. GRB 141229A: Swift-XRT observations
  86. GRB 141225A: Swift-XRT refined Analysis
  87. Swift XRT and UVOT observations of GRB141222A
  88. GRB 141215A: further Swift-XRT observations and afterglow detection
  89. GRB 141221A: Swift-XRT refined Analysis
  90. GRB 141220A: Swift-XRT refined Analysis
  91. GRB 141215A: Swift-XRT observations
  92. GRB 141212B: Swift-XRT refined Analysis
  93. GRB 141212A: Swift-XRT refined Analysis
  94. GRB 141207A: Swift-XRT afterglow candidate detection
  95. GRB 141207A: Swift-XRT observations
  96. GRB 141205A: XRT observations
  97. GRB 141202A: Swift/UVOT Detection of a Variable Source Near the IPN Error Box
  98. GRB 141202A: Swift XRT observations
  99. GRB 141130A: Swift-XRT refined Analysis
  100. GRB 141121A: Swift-XRT refined Analysis

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