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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"

27408 results found.

  1. GRB 090809: Swift-XRT refined analysis
  2. GRB090809: Swift/UVOT observations
  3. GRB 090809: Swift-BAT refined analysis
  4. GRB 090809: Swift detection of a burst with a possible optical counterpart
  5. GRB 090807: Liverpool Telescope observations
  6. GRB 090807: Swift/UVOT Upper Limits
  7. GRB 090807: Swift-XRT refined analysis
  8. GRB 090807, Swift-BAT refined analysis
  9. GRB 090807, RIMOTS optical upper limits
  10. GRB 090807: Swift detection of a burst
  11. Fermi Gamma-ray Burst Monitor trigger 271275771 is not a GRB
  12. GRB 090802B: Fermi GBM detection
  13. GRB 090802: Fermi GBM detection
  14. Swift-BAT trigger 358760 is most likely not a GRB
  15. Swift trigger 358760 is probably a noise event
  16. GRB 090717A: Suzaku WAM observation of the prompt emission
  17. GRB 090709A : Quick look analysis of the Suzaku observation
  18. GRB 090728: Swift-BAT refined analysis
  19. GRB 090727: GRT Optical Observation
  20. GRB 090728: Swift XRT refined analysis
  21. GRB 090727: optical observations
  22. GRB 090726: GRT Optical Observation
  23. GRB 090727: Swift/UVOT Upper Limits
  24. GRB 090728: Swift/UVOT Upper Limits
  25. GRB 090728, RIMOTS optical upper limits
  26. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  27. GRB 090728: Swift detection of a burst
  28. GRB 090727: Swift-BAT refined analysis
  29. GRB 090727: Swift-XRT refined analysis
  30. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  31. GRB 090727: Liverpool Telescope possible OT candidate
  32. GRB 090727: Swift detection of a burst
  33. GRB090726: Swift/UVOT observations
  34. GRB 090726, Swift-BAT refined analysis
  35. GRB 090726: D50 optical observations
  36. GRB 090711: Fermi GBM detection
  37. GRB090726: 6-meter telescope redshift
  38. GRB 090726: Swift-XRT Team refined analysis
  39. GRB 090726: optical transient candidate
  40. GRB 090726: Swift/UVOT Finding Chart Observation
  41. GRB 090726: Swift-XRT position of probable counterpart
  42. GRB 090726: Swift detection of a burst
  43. Swift Trigger 358354 is not a GRB
  44. Konus-Wind and Konus-RF observations of GRB 090719
  45. Konus-RF and Konus-Wind observations of GRB 090718B
  46. Fermi Gamma-ray Burst Monitor triggers 269935914 through 270021937 are not GRBs
  47. Konus-Wind observations of bright hard GRB 090720B
  48. IPN Triangulation of bright GRB 090720B
  49. GRB 090720: Gemini-North Imaging and Optical Afterglow
  50. GRB 090720B: Fermi GBM detection
  51. Swift XRT and UVOT refned analysis of GRB 090720
  52. GRB 090709A: Swift XRT Timing Analysis
  53. GRB 090720 Source found in ground processing of Swift-BAT data
  54. GRB 090717B: Fermi GBM detection
  55. GRB 090717: Fermi GBM detection
  56. GRB 090719: Fermi GBM detection
  57. GRB 090718B: Fermi GBM detection
  58. GRB 090718: Fermi GBM detection
  59. GRB 090720: Fermi GBM detection
  60. GRB 090715A: Suzaku WAM observation of the prompt emission
  61. GRB 090709A - CARMA mm Observations
  62. GRB 090715A: VLA observations
  63. Konus-Wind observations of short/hard GRB 090715A
  64. GRB 090715B: MASTER optical limit
  65. GRB 090715A: Swift-BAT refined analysis
  66. GRB 090715B: Swift/UVOT followup observations
  67. GRB 090715B: break in the optical afterglow decay
  68. GRB 090715B: Swift XRT Refined Analysis
  69. GRB 090715B: Swift-BAT refined analysis
  70. GRB 090715B - Liverpool Telescope Optical Afterglow Candidate
  71. GRB 090715B: Swift detection of a burst with a possible optical counterpart
  72. GRB 090715A: ROTSE-III Optical Limits
  73. GRB 090715: Swift detection of a short hard burst
  74. Swift satellite anomaly
  75. GRB090713 optical limit by "Pi of the Sky"
  76. GRB 090712: Fermi GBM observation
  77. GRB 090713: Fermi GBM detection
  78. GRB 090712: Swift-BAT refined analysis
  79. GRB 090712: Swift detection of a burst
  80. GRB 090709A: Xinglong TNT optical upper limit
  81. GRB 090709A: Suzaku WAM observation of the prompt emission
  82. GRB 090709A: Swift UVOT upper limits
  83. GRB 090709B: Fermi GBM detection
  84. GRB 090709A: confirmation of the periodicity in the SPI-ACS data
  85. GRB 090709A: P60 Observations
  86. GRB 090709A: Quasiperiodic variations in the BAT light curve
  87. GRB 090709A: NOT optical observations
  88. GRB 090709A: RAPTOR Limits During Gamma-Ray Emission
  89. GRB 090709A: Swift XRT Refined Analysis
  90. GRB 090709B, Swift-BAT refined analysis
  91. GRB 090709A: Swift-BAT refined analysis
  92. GRB090709A: High Energy BAT/XRT Analysis Suggests Low to Moderate Redshift
  93. GRB 090709A: Wyoming Infrared Observatory NIR upper limits
  94. GRB 090709A, RIMOTS optical upper limits
  95. GRB 090709B: Swift detection of a burst
  96. GRB 090708 : Fermi GBM detection
  97. GRB 090626: Suzaku WAM observation of the prompt emission
  98. GRB 090709: PAIRITEL NIR Upper Limits
  99. GRB 090704: Fermi GBM observation
  100. GRB 090709: ROTSE-III Optical Limits

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