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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"

18430 results found.

  1. GRB 120302A: GROND detection of an afterglow candidate
  2. GRB 120302A, Swift-BAT refined analysis
  3. GRB 111222A: Swift observation on 2012 February 06/07
  4. GRB 120302A found in ground analysis of BAT data
  5. GRB 120229A, Swift-BAT refined analysis
  6. GRB 120229A: Swift detection of a short burst
  7. IPN Triangulation of GRB 120226A
  8. GRB 120226A: Fermi-LAT detection of a burst
  9. GRB 120224A: GROND detection of the afterglow candidate
  10. GRB 120224A: Swift-XRT refined Analysis
  11. Swift Trigger 516027 is CC Eri
  12. GRB 120224A: Swift/UVOT Upper Limits
  13. GRB 120224A: Swift-BAT refined analysis
  14. GRB 120224A: FTN optical observations
  15. GRB 120224A: Enhanced Swift-XRT position
  16. GRB 120224A: Swift detection of a burst
  17. GRB 120219A: MASTER prompt and early optical limit and OT discussion
  18. GRB 120219A: 1.23m CAHA optical observations
  19. GRB 120219A, optical observations
  20. GRB 120219A: Swift-XRT refined Analysis
  21. GRB 120219A: Swift/UVOT Upper Limits
  22. GRB 120219A: Swift-BAT refined analysis
  23. GRB 120219A: Enhanced Swift-XRT position
  24. GRB 120219A: MASTER-NET prompt and early optical observations
  25. GRB 120219A: Swift detection of a burst
  26. GRB 120218A: Swift-BAT refined analysis
  27. GRB 120218A: Swift detection of a burst
  28. GRB 120215A: Swift/UVOT Upper Limits
  29. GRB 120215A: Swift-XRT refined Analysis
  30. GRB 120215A: Enhanced Swift-XRT position
  31. GRB 120215A: Swift-BAT refined analysis
  32. GRB 120215A: Swift detection of a burst
  33. GRB 120213A: Swift-XRT refined Analysis
  34. GRB 120213A: Swift/UVOT Upper Limits
  35. GRB 120212A: Fermi GBM observation
  36. GRB 120213A: Enhanced Swift-XRT position
  37. GRB 120213A: Swift-BAT refined analysis
  38. GRB 120213A: MASTER-NET early optical observations
  39. GRB 120213A: Prompt enhanced Swift-XRT position
  40. GRB 120212A: Swift-XRT refined Analysis
  41. GRB 120213A: Swift detection of a burst
  42. GRB 120212A: Swift/UVOT Detection
  43. GRB 120212A: Swift-BAT refined analysis
  44. GRB 120212A: Enhanced Swift-XRT position
  45. GRB 120212A: Kanata/HOWPol optical observation
  46. GRB 120212A: Swift-XRT observations
  47. GRB 120212A: Swift/UVOT detection
  48. GRB 120211A: GROND Upper limits
  49. GRB 120212A: Swift detection of a burst
  50. GRB 120211A, optical observations
  51. GRB 120211A: Swift-XRT refined Analysis
  52. GRB 120211A: Swift/UVOT Upper Limits
  53. GRB 120211A: MASTER early optical observations
  54. GRB 120211A: Swift-BAT refined analysis
  55. GRB 120211A: Enhanced Swift-XRT position
  56. GRB 120211A - Faulkes Telescope South Observations
  57. GRB 120211A: Swift detection of a burst
  58. LS I +61 303: Swift-BAT refined analysis
  59. GRB 120202A: D50 optical limits
  60. Swift detection of a burst from LS I +61 303
  61. GRB 120202A: GROND observations
  62. GRB 120202A: WHT, Gemini & UKIRT candidate afterglow
  63. GRB 120202A: Swift/XRT and UVOT observations
  64. GRB 111228A: Possible host detected by Swift/UVOT
  65. IPN Triangulation of GRB 120129A (long/intense)
  66. GRB 120118B: optical upper limit
  67. GRB 120116A: optical upper limit
  68. GRB 120119A: EVLA observations
  69. GRB 120119A: GRT detection of early afterglow
  70. GRB 120119A: optical upper limit
  71. GRB 120121A: Swift/UVOT Upper Limits
  72. GRB 120121A: Swift-XRT refined Analysis
  73. GRB 120121A: Swift-BAT refined analysis
  74. GRB 120121A: Enhanced Swift-XRT position
  75. GRB 120121A: ISON-NM optical observations
  76. GRB 120121A: Swift-XRT position
  77. GRB 120121A: Swift detection of a burst
  78. GRB 120119A, Swift-BAT refined analysis
  79. GRB 120119A: TAROT La Silla observatory optical observations
  80. GRB 120119A: optical observations
  81. GRB 120119A: Swift/UVOT Observations
  82. GRB 120119A: Swift-XRT refined Analysis
  83. GRB 120119A: Enhanced Swift-XRT position
  84. GRB 120119A: Fermi GBM observation
  85. GRB 120118B, Swift-BAT refined analysis
  86. Konus-Wind observation of GRB 120119A
  87. GRB 120119A: optical observations
  88. GRB 120118B: Swift-XRT refined Analysis
  89. GRB 120118B : Lulin Optical limit
  90. GRB 120119A: GROND Detection of the Optical/NIR Afterglow
  91. GRB 120118B: Swift/UVOT Upper Limits
  92. GRB 120119A: Liverpool Telescope afterglow detection
  93. GRB 120119A: PAIRITEL NIR Detection
  94. GRB 120119A: Swift detection of a burst with an optical counterpart
  95. GRB 120118B: NOT observations
  96. GRB 120118B: Enhanced Swift-XRT position
  97. GRB 120118B: Faulkes Telescope South observations
  98. GRB 120118B: Swift-XRT position
  99. GRB 120118B: MASTER optical observations
  100. GRB 120118B: Swift detection of a burst

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