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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"

6400 results found.

  1. GRB 150301B: Swift-XRT refined Analysis
  2. GRB 150301B: Fermi GBM detection
  3. GRB 150301A: Swift-XRT refined Analysis
  4. GRB 150301C : (Swift trigger 633105) Swift observations
  5. GRB 150301A: Fermi GBM observation
  6. GRB 150220A: Fermi GBM observation
  7. GRB 150220A: Swift-XRT observations
  8. GRB 150222A: Swift-XRT refined Analysis
  9. GRB 150219A: Fermi GBM observation
  10. GRB 150219A: Swift-XRT afterglow detection
  11. GRB 150213B: Swift-BAT refined analysis
  12. GRB 150213B: Swift-XRT refined Analysis
  13. GRB 150213A: Fermi GBM detection
  14. GRB 150212A: Swift-XRT refined Analysis
  15. GRB 150210A: Swift-XRT observations
  16. GRB 150211A: Swift-XRT refined Analysis
  17. GRB 150210A: Fermi-LAT detection
  18. GRB 150210A: Fermi GBM detection
  19. GRB 150101B/ Swift J123205.1-105602: Second epoch Chandra observations
  20. GRB 150202B: Swift/XRT afterglow confirmation
  21. GRB 150204A: Swift/XRT afterglow confirmation
  22. GRB 150206A: Swift-XRT refined Analysis
  23. GRB 150206B: Fermi GBM detection
  24. GRB 150204A: Swift-XRT observations
  25. GRB 150204A: Fermi GBM detection
  26. GRB 150202B: Swift XRT/UVOT observations
  27. Swift Trigger 629693 was a noise event
  28. GRB 150203A: Swift-XRT refined Analysis
  29. GRB 150202A: Swift-XRT refined Analysis
  30. GRB 150203A: Fermi GBM observation
  31. GRB 150202B: Fermi GBM detection
  32. GRB 150202B: Fermi-LAT detection
  33. GRB 150201A: Swift-XRT refined Analysis
  34. GRB 150201A: Fermi GBM observation
  35. GRB 150127B: Fermi GBM detection
  36. Konus-Wind observation of GRB 150126A reveals its ultra-long nature
  37. GRB 150127A: Fermi-LAT detection
  38. GRB150127A: Fermi GBM Detection
  39. GRB 150126A: Fermi GBM Detection
  40. GRB 150123A: Swift-XRT observations
  41. GRB 150120B: Additional P60 observations
  42. GRB 150120A: Swift-XRT refined Analysis
  43. GRB 150118C: Fermi GBM Detection
  44. GRB 150120B: Swift-XRT refined Analysis
  45. GRB 150120A: Fermi GBM observation
  46. GRB 150101B/Swift J123205.1-105602: XMM-Newton observation
  47. GRB 150118B: Fermi GBM Detection
  48. GRB 150118B: Fermi-LAT detection
  49. GRB 150110C: Swift-XRT observations
  50. GRB 150110B: Swift-XRT refined Analysis
  51. GRB 150110B: Fermi GBM Detection
  52. GRB 150110A: Fermi GBM Detection
  53. GRB 150101B/Swift J123205.1-105602: Chandra observations
  54. GRB 150105A: Fermi GBM detection
  55. GRB 150103A: Swift-XRT refined Analysis
  56. GRB 150101B: Fermi GBM detection
  57. Swift J123205.1-105602: XRT and UVOT observations of soft short burst source
  58. GRB 150101A: Fermi GBM detection
  59. GRB 150101A: Swift-XRT refined Analysis
  60. Swift-XRT and UVOT follow-up of iPTF14jko (GRB 141230A)
  61. GRB 141230A: Fermi GBM detection
  62. GRB 141229A: Swift-XRT observations
  63. GRB 141229A: Fermi GBM detection
  64. GRB 141225A: MASTER-SAAO OT light curve
  65. GRB 141225A: Fermi GBM detection
  66. GRB 141225A: Swift-XRT refined Analysis
  67. Swift XRT and UVOT observations of GRB141222A
  68. GRB 141222A: Fermi GBM detection
  69. GRB 141222A: Fermi-LAT detection
  70. GRB 141215A: further Swift-XRT observations and afterglow detection
  71. GRB 141221A: Fermi GBM observation
  72. GRB 141221A: Swift-XRT refined Analysis
  73. GRB 141220A: Fermi GBM observation
  74. GRB 141220A: Swift-XRT refined Analysis
  75. GRB 141215A: Swift-XRT observations
  76. GRB 141215A: Fermi GBM detection
  77. GRB 141212B: Swift-XRT refined Analysis
  78. GRB 141212A: Swift-XRT refined Analysis
  79. GRB 141207A: Swift-XRT afterglow candidate detection
  80. GRB 141207A: Fermi GBM detection
  81. GRB 141207A: Swift-XRT observations
  82. GRB 141207A: Fermi-LAT Detection
  83. GRB 141205A: Fermi GBM detection
  84. GRB 141205A: XRT observations
  85. GRB 141202A: Swift/UVOT Detection of a Variable Source Near the IPN Error Box
  86. GRB 141202A: Swift XRT observations
  87. GRB 141202A: Fermi GBM Detection
  88. GRB 141130A: Swift-XRT refined Analysis
  89. GRB 141121A: TSHAO optical observations
  90. GRB 141121A: TSHAO optical observations
  91. GRB 141118A: Fermi GBM Detection
  92. GRB 141121A: Swift-XRT refined Analysis
  93. GRB 141104A: further Swift-XRT observations and afterglow candidate
  94. GRB 141109A: Terskol photometry
  95. Konus-Wind observation of GRB 141109A
  96. GRB141109A : Xinglong TNT optical observation
  97. GRB 141109B: Swift-XRT refined Analysis
  98. GRB 141109A: Swift-XRT refined Analysis
  99. GRB 141104A: Swift-XRT observations
  100. GRB 141028A: TShAO optical observation

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