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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"

24903 results found.

  1. GRB 060923B: Swift XRT Refined Analysis
  2. GRB 060923A: Swift XRT refined analysis
  3. GRB 060923A: Keck and Gemini Observations
  4. GRB 060923C: Xinglong TNT optical observations
  5. GRB 060923B, Swift-BAT refined analysis
  6. GRB 060923C: Swift detection of a burst
  7. GRB 060923B: Swift detection of a burst
  8. GRB 060923, Swift-BAT refined analysis
  9. GRB 060923: UKIRT nIR observations - candidate afterglow
  10. GRB060923 - SDSS Pre-Burst Observations
  11. GRB 060923: Swift detection of a burst
  12. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  13. GRB 060919 : Faulkes South Telescope Observations
  14. GRB 060919, Swift-BAT refined analysis
  15. GRB060919: XRT refined analysis
  16. GRB 060919: TAROT optical observations
  17. GRB 060919: Swift detection of a burst
  18. GRB 060912A: VLA Observation
  19. GRB 060912A: Probable Host Galaxy
  20. GRB 060912, Swift-BAT refined analysis
  21. GRB 060912: Correction to GCN 5559
  22. GRB 060912: Swift detection of a burst with an optical afterglow
  23. VLA observations of GRB 060908
  24. GRB 060908, Swift-BAT refined analysis
  25. GRB 060908 - SDSS Pre-burst Observations
  26. GRB 060908: REM optical prompt observation
  27. GRB 060908: Swift detection of a burst with a bright optical counterpart
  28. GRB 060904A: Suzaku/WAM observation of the prompt emission
  29. GRB060906 , optical observation
  30. GRB 060906: Early RAPTOR optical limits
  31. GRB 060906, Swift-BAT refined spectral analysis
  32. GRB 060906: Swift/XRT Refined Analysis
  33. VLT redshift of GRB 060906
  34. GRB 060906, Swift-BAT refined analysis
  35. GRB 060906: Confirmation of P60 Optical Afterglow
  36. GRB 060906 (?): P60 Optical Afterglow Candidate
  37. GRB060904b, optical observations
  38. GRB060904A: Swift/UVOT optical observations
  39. GRB 060904A: Subaru NIR observation
  40. GRB 060904B: Swift-BAT refined analysis
  41. GRB 060904A: Refined analysis of the Swift-BAT burst
  42. GRB 060904A: Suzaku-XIS and -HXD observation plan
  43. GRB 060904A: P60 Observations
  44. GRB 060904B: Optical observations at Crni Vrh
  45. GRB 060904B: TAROT optical counterpart observations
  46. GRB060904B - SDSS Pre-Burst Observations
  47. GRB 060904: TAROT optical observations
  48. GRB 060904B: Swift detection of a burst with optical counterpart
  49. GRB060904 - SDSS Pre-Burst Observations
  50. GRB 060904: Swift detection of a bright burst
  51. GRB060901: Optical observations
  52. 060901: Swift UVOT followup observations
  53. GRB 060901: Swift/XRT Refined Analysis
  54. GRB 060901: Swift/XRT Position
  55. GRB 060901: a long GRB detected by INTEGRAL
  56. Two bright bursts from SGR 1806-20 detected with IBAS
  57. GRB 060605, observations using an Integral Field Unit
  58. GRB 060604: VLA Observation
  59. GRB 060814: Suzaku/WAM observation of the prompt emission
  60. GRB 060605: VLA Observation
  61. GRB 060707: VLA observation
  62. GRB 060825: VLA observations
  63. GRB060826 - SDSS Pre-Burst Observations
  64. GRB 060826(?): Swift detection of a possible burst
  65. GRB 060825: XRT Team Refined Analysis
  66. GRB 060825: Swift-BAT Refined Analysis
  67. GRB 060813: Swift/BAT, Konus-Wind, and Suzaku/WAM joint prompt spectral analysis
  68. GRB 060825: TNG optical observations
  69. GRB 060825: TAROT optical observations
  70. GRB 060825: P60 Observations
  71. GRB 060825: Swift detection of a burst
  72. GRB060801: host galaxy redshift
  73. GRB060729: analysis of XMM-Newton observation
  74. GRB 060729, SMARTS optical/IR observations
  75. GRB 060813: A long, bright GRB detected with Suzaku WAM
  76. Konus-Wind observation of GRB 060814
  77. GRB 060814: Refined analysis of the Swift-BAT burst
  78. GRB 060814: P60 Observations
  79. GRB 060814: P200 NIR Observations
  80. GRB060805B: optical observations
  81. GRB 060814: Swift XRT refined analysis
  82. GRB 060814: VLT optical limits
  83. GRB 060814 - SDSS Pre-Burst Observations
  84. GRB 060814: TAROT optical observations
  85. GRB 060814: Swift detection of a bright burst
  86. Konus-Wind observation of GRB 060813
  87. GRB 060813: Swift XRT refined analysis
  88. GRB 060813: Refined analysis of the Swift-BAT burst
  89. GRB 060813: Swift detection of a burst
  90. GRB051109B: Late-time Radio Observations
  91. Swift detection of an outburst from the 4U 1246-58 LMXB burster
  92. GRB060807: Possible Highly Significant X-ray Emission Lines
  93. GRB 060729: An update on the Swift XRT and UVOT observations
  94. GRB060717: optical observations
  95. GRB060807: Optical limiting magnitudes
  96. GRB 060805B: XRT Team Analysis
  97. GRB060806 is similar to previous activity of SGR1806-20
  98. GRB 060807: XRT Team refined analysis
  99. GRB 060807: Refined analysis of the Swift-BAT burst
  100. GRB060807: optical afterglow candidate

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