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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"

28041 results found.

  1. GRB 150302A: Swift/UVOT Upper Limits
  2. GRB 150302A: MITSuME Okayama upper limits
  3. GRB 150301C: XRT detection of a potential counterpart of BAT trigger 633105
  4. GRB 150302A: Swift-XRT refined Analysis
  5. GRB 150302A: Enhanced Swift-XRT position
  6. GRB 150301B: Swift-XRT refined Analysis
  7. GRB 150220A: further Swift-XRT observations
  8. GRB 150301B: Swift/UVOT Observations
  9. GRB 150301B: LCOGT-Sutherland observations
  10. GRB 150302A: NOT afterglow candidate
  11. GRB 150302A: Swift detection of a burst
  12. GRB 150301B: Fermi GBM detection
  13. GRB 150301B: Swift-BAT refined analysis
  14. GRB 150301B: GROND afterglow observations
  15. GRB 150301A: Swift/UVOT Upper Limits
  16. GRB 150301B: Enhanced Swift-XRT position
  17. GRB 150301A: Swift-BAT refined analysis
  18. GRB 150301B: MASTER early OT detection
  19. GRB 150301A: Swift-XRT refined Analysis
  20. GRB 150301C : (Swift trigger 633105) Swift observations
  21. GRB 150301B: Swift detection of a burst with an optical afterglow
  22. GRB 150301A: GROND Observations
  23. Trigger 633105 is likely not a GRB
  24. GRB 150301A: Swift detection of a short burst or new SGR
  25. Swift-BAT refined analysis of magnetar 4U 0142+61 (Trigger 632888)
  26. Fermi GBM Observations of Magnetar 4U 0142+61
  27. Trigger 632888: Swift detection of the magnetar 4U 0142+61
  28. GRB 150222A: Further GROND Observations
  29. GRB 150220A: Swift-XRT observations
  30. GRB 150222A: I-band observations from OSN
  31. GRB 150222A: Swift/UVOT Upper Limits
  32. GRB 150222A: Swift-XRT refined Analysis
  33. GRB 150222B: MAXI/GSC detection
  34. Fermi GBM Observations of SGR 1935+2154
  35. GRB 150222A: GROND optical afterglow candidate
  36. GRB 150222A: Enhanced Swift-XRT position
  37. GRB 150222A: TNG optical observations
  38. GRB 150222A: Swift-BAT refined analysis
  39. SGR 1935+2154: Swift-BAT refined analysis
  40. GRB 150222A: Mondy optical observations
  41. GRB 150222A: Zadko observatory - Gingin optical observations
  42. GRB 150222A: Swift detection of a burst
  43. Swift detection of an outburst from SGR 1935+2154
  44. GRB 150213B, the review of the sky area in plate archives
  45. GRB 150219A: Swift-XRT afterglow detection
  46. Trigger 631747: Swift detection of 4U 0614+09
  47. GRB 150213B: AAO photometry
  48. GRB 150219A: A long GRB detected by INTEGRAL
  49. GRB 150213B: Enhanced Swift-XRT position
  50. GRB 150212A, the review of the sky area in plate archives
  51. GRB 150213B: Swift/UVOT Detection
  52. GRB 150213B: Swift-BAT refined analysis
  53. GRB 150213B: RATIR Optical and NIR Observations
  54. GRB 150213B: Swift-XRT refined Analysis
  55. GRB 150213B: AAO optical observations
  56. GRB 150213B: optical detection from the NOT
  57. GRB 150212A: Swift/UVOT Observations
  58. GRB 150213B: Swift detection of a burst with an optical afterglow
  59. GRB 150213A: Fermi GBM detection
  60. GRB 150212A: Swift-XRT refined Analysis
  61. GRB 150212A: RATIR Optical and NIR Observations
  62. GRB 150212A: Khureltogot optical upper limit
  63. GRB 150212A: Skynet DSO14/GORT observations
  64. GRB 150212A: Swift-BAT refined analysis
  65. GRB 150212A: P60 Afterglow Retraction
  66. GRB 150210A: Swift-XRT observations
  67. GRB 150212A: Swift-XRT afterglow detection
  68. GRB150212A: P60 Afterglow Candidate
  69. GRB 150212A: Swift detection of a burst
  70. GRB 150211A iTelescope observation
  71. GRB 150211A: Swift/UVOT Upper Limits
  72. GRB 150211A: Swift-BAT refined analysis
  73. GRB 150211A: Mondy optical upper limit
  74. GRB 150211A: Swift-XRT refined Analysis
  75. GRB 150210A: Fermi-LAT detection
  76. GRB 150211A: RATIR Optical and NIR Observations
  77. GRB 150211A: Swift-XRT observations
  78. GRB 150211A: Swift detection of a burst
  79. GRB 150210A: Fermi GBM detection
  80. GRB 150204A: GROND observations
  81. GRB 150202B: Swift/XRT afterglow confirmation
  82. GRB 150204A: Swift/XRT afterglow confirmation
  83. GRB 150206A: Swift-BAT refined analysis
  84. GRB 150203A iTelescope observation
  85. GRB 150206A: Swift/UVOT Detection
  86. GRB 150206A: Swift-XRT refined Analysis
  87. GRB 150206A: GROND afterglow observations
  88. GRB 150206A: Enhanced Swift-XRT position
  89. GRB 150206B: Fermi GBM detection
  90. Trigger 630047: Swift detection of 1RXS J180408.9-342058
  91. GRB 150206B: iPTF Optical Observations
  92. GRB 150206A: MAXI/GSC detection
  93. GRB 150206A: Swift detection of a burst with an optical afterglow
  94. GRB 150204A: LCOGT-Sutherland and Siding Springs observations
  95. GRB 150204A: Swift/UVOT Upper Limits
  96. GRB 150203A: Swift-BAT refined analysis
  97. GRB 150204A: Swift-XRT observations
  98. GRB 150204A: Fermi GBM detection
  99. GRB 150204A BAT refined analysis
  100. GRB 150202B: Swift XRT/UVOT observations

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