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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 120328A: Swift/UVOT Upper Limits
  2. GRB 120328A: Swift-XRT refined Analysis
  3. IPN Triangulation of GRB 120328B (long/intense)
  4. GRB 120328A: Swift-BAT refined analysis
  5. GRB 120328A: Enhanced Swift-XRT position
  6. GRB 120328A: TAROT La Silla observatory optical observations
  7. Skynet/PROMPT observations of GRB120328A
  8. GRB 120328A: Swift detection of a burst
  9. GRB 120326A: Fermi GBM Observation
  10. GRB 120327A afterglow detection
  11. GRB 120326A: PAIRITEL NIR Observations
  12. GRB 120326A: Bassano Bresciano Observatory optical observations
  13. GRB 120327A: Swift-XRT refined Analysis
  14. GRB 120327A: Swift/UVOT further analysis
  15. GRB 120327A: Swift-BAT refined analysis
  16. GRB 120327A: Enhanced Swift-XRT position
  17. GRB 120327A: X-shooter redshift
  18. GROND observations of GRB 120327A
  19. GRB 120327A: Liverpool Telescope Observations
  20. GRB 120327A: TAROT La Silla observatory optical detection
  21. GRB 120327A: Swift detection of a burst with an optical counterpart
  22. GRB 120326A: Swift-BAT refined analysis
  23. GRB 120326A: Swift-XRT refined Analysis
  24. GRB 120326A: Swift/UVOT Detection
  25. GRB 120326A: Optical observations at Crni Vrh
  26. GRB120326A: IAC80 observations
  27. GRB 120326A: Liverpool Telescope observations
  28. GRB 120326A: Enhanced Swift-XRT position
  29. Skynet/Dolomiti Observations of GRB120326A
  30. GRB 120326A: TAROT Calern observatory afterglow optical detection
  31. GRB 120326A: ROTSE-III Optical Limits
  32. GRB 120326A: Swift detection of a burst
  33. IPN Triangulation of GRB 120323A (short/very intense)
  34. GRB 120324A: Swift-XRT refined Analysis
  35. Konus-Wind observation of GRB 120324A
  36. GRB 120324A: GROND observations
  37. GRB 120324A: Swift-BAT refined analysis
  38. GRB 120324A: Swift/UVOT Upper Limits
  39. GRB 120324A: TAROT La Silla observatory optical observations
  40. GRB 120324A: Enhanced Swift-XRT position
  41. GRB 120324A: Liverpool Telescope optical candidate
  42. GRB 120324A: UVOT Finding Chart Observation
  43. GRB 120324A: Swift detection of a burst
  44. Simultaneous optical images of Swift pointing are available by GRT
  45. GRB 120320A: Zadko optical observations
  46. GRB 120320A: Swift/UVOT Upper Limits
  47. GRB 120320A: BOOTES-4 optical upper limit
  48. GRB 120320A: Swift-XRT refined Analysis
  49. GRB 120320A, Swift-BAT refined analysis
  50. GRB 120320A: Enhanced Swift-XRT position
  51. IPN Triangulation of GRB 120316A
  52. GRB 120320A: MASTER optical observations
  53. GRB 120320A: Swift detection of a burst
  54. Trigger 517876 is a Swift detection of GX 5-1
  55. GRB 120302A: Swift XRT refined analysis
  56. GRB 120312A: CrAO optical upper limit
  57. GRB 120311A: Optical follow-up
  58. GRB 120311A: C88 optical limits
  59. GRB 120312A: Swift/UVOT Upper Limits
  60. GRB 120312A: MASTER-NET optical observations
  61. GRB 120312A: NOT observations
  62. GRB 120312A: Swift-XRT refined Analysis
  63. GRB 120312A: Swift-BAT refined analysis
  64. GRB 120311A: VLT/X-shooter observations
  65. GRB 120311B: C88 optical limits
  66. GRB 120312A: Swift detection of a burst
  67. GRB 120311B: Swift/UVOT Upper Limits
  68. GRB 120311B: Faulkes Telescope North observations
  69. GRB 120311B: Swift-XRT refined Analysis
  70. GRB 120311A: Swift-XRT refined Analysis
  71. GRB 120311B: Enhanced Swift-XRT position
  72. GRB 120311B: Swift-BAT refined analysis
  73. GRB 120311B: Swift-XRT observations
  74. GRB 120311A, Swift-BAT refined analysis
  75. GRB 120311B: Swift detection of a burst
  76. GRB 120311A: Swift/UVOT Upper Limits
  77. GRB 120311A: Enhanced Swift-XRT position
  78. GRB 120311A: Swift-XRT observations
  79. GRB 120311A: Liverpool Telescope optical candidate
  80. GRB 120311A: Swift detection of a burst
  81. GRB 120308A: 1.23m CAHA I-band observations
  82. GRB 120308A: Swift/UVOT Detection
  83. GRB 120308A: Swift-XRT refined Analysis
  84. GRB 120308A: Enhanced Swift-XRT position
  85. GRB 120308A: Swift-BAT refined analysis
  86. GRB 120308A: PAIRITEL NIR observations
  87. GRB 120308A: confirmation of the optical afterglow
  88. GRB 120308A: Liverpool Telescope optical afterglow candidate
  89. GRB 120308A: Swift detection of a burst
  90. GRB 120305A: D50 optical limits
  91. GRB 120305A: Swift spectral lag analysis
  92. GRB 120302A: Fermi GBM Observation
  93. GRB 120302A: Swift-BAT refined position and a possible XRT and UVOT counterpart
  94. GRB 120305A: Swift/UVOT Upper Limits
  95. GRB 120305A: Swift-XRT refined Analysis
  96. GRB 120305A: Enhanced Swift-XRT position
  97. GRB 120305A: Swift-BAT refined analysis
  98. GRB 120305A - Liverpool Telescope Observations
  99. GRB 120305A: MASTER-NET early optical observations
  100. GRB 120305A: Swift detection of a short burst

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