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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"

6190 results found.

  1. GRB 110223B: Swift-XRT refined Analysis
  2. GRB110213B: X-ray afterglow confirmation
  3. Swift XRT and UVOT Observations of OT 110215
  4. GRB 110213A: TNT optical observations
  5. GRB110213A: RAPTOR Early Optical Peak and Plateau Measurements
  6. GRB 110212A: Swift XRT and UVOT observations
  7. Swift GRB110213A: interesting behaviour
  8. GRB 110213A: Fermi GBM observation
  9. GRB 110205A: Konkoly optical observations
  10. GRB 110213B: Swift XRT observation
  11. GRB 110213A: Swift-XRT refined Analysis
  12. GRB 110213A: KAIT observations
  13. GRB 110201A: Subaru/MOIRCS Ks-band photometry
  14. GRB 110210A: Swift-XRT refined Analysis
  15. GRB 110206A: Swift-XRT confirmation of the X-ray afterglow
  16. GRB 110207A: Swift-XRT observations
  17. GRB 110208A: Swift-XRT refined Analysis
  18. GRB 110207A: Fermi GBM observation
  19. GRB 110205A - Continued PAIRITEL NIR Observations
  20. GRB 110206A: UVOT detection of afterglow candidate
  21. GRB 110206A: Swift detection of a probable X-ray afterglow
  22. GRB 110205A: Lightbuckets Optical Observations
  23. GRB 110205A: Swift-XRT refined Analysis
  24. GRB 110205A: GRAS005 optical observations
  25. GRB 110205A: PAIRITEL NIR Afterglow Detection
  26. GRB 110205A: Swift detection of a burst with an optical candidate
  27. GRB 110128A: Fermi GBM detection
  28. GRB 110201A: Swift-XRT refined Analysis
  29. GRB 110125A: Fermi GBM detection
  30. GRB 101112A: Maidanak and CrAO optical observations
  31. GRB 110128A: Swift-XRT refined Analysis
  32. GRB 110123A: Fermi GBM detection
  33. GRB 110120A: Fermi LAT detection
  34. GRB 101225A: CQUEAN optical observation
  35. GRB 110119A: Fermi GBM detection
  36. GRB 110120A: Fermi GBM detection
  37. GRB 110119A: Swift-XRT refined Analysis
  38. GRB 110119A: PAIRITEL NIR Afterglow Detection
  39. GRB 110112B: Swift XRT and UVOT observations of the INTEGRAL burst
  40. GRB 110107A: Swift-XRT afterglow confirmation
  41. GRB 110112A: Swift-XRT refined Analysis
  42. GRB110112A: TNT optical afterglow candidate
  43. GRB 110107A: Swift-XRT Afterglow Candidate
  44. GRB 110106B: Fermi GBM detection
  45. GRB 110106B: Swift-XRT refined Analysis
  46. GRB 110106A: Swift-XRT refined Analysis
  47. GRB 110102A: Swift-XRT refined Analysis
  48. GRB 110102A: Fermi GBM observation
  49. GRB 101225A: WHT observations
  50. GRB 101225A: Swift-XRT refined Analysis
  51. GRB 101224A: Fermi GBM observation
  52. GRB 101224A: Swift-XRT refined Analysis
  53. GRB 101219B: Swift-XRT refined Analysis
  54. GRB 101219B: Fermi GBM observation
  55. GRB 101219A: Swift-XRT refined Analysis
  56. GRB 101219A: SARA-N Upper Limit
  57. GRB 101213A: Fermi GBM observation
  58. GRB 101213A: Swift-XRT refined Analysis
  59. GRB 101204A: Swift-XRT refined Analysis
  60. GRB 101204A Swift-XRT/UVOT afterglow candidate
  61. GRB 101201A: Fermi GBM observation
  62. GRB 101201A: Swift-XRT refined Analysis
  63. GRB 101123A: Fermi GBM detection
  64. GRB 101117B: Swift-XRT refined analysis
  65. GRB 101114A: Confirmation of the X-ray afterglow
  66. GRB 101114A: Swift-XRT candidate afterglow detection and analysis
  67. GRB 101112A: Fermi GBM detection
  68. GRB 101112A: optical observations
  69. GRB 101112A - XRT source detection/analysis
  70. GRB 101030A : MOA optical observation
  71. GRB 101030A : Swift XRT refined analysis
  72. GRB 101024A: Swift XRT refined analysis
  73. GRB 101023A: miniTAO/ANIR NIR detection
  74. GRB 101024A: Fermi GBM observation
  75. GRB 101023A: Fermi GBM observation
  76. GRB 101023A: Swift-XRT Team Refined Analysis
  77. GRB 101011A: miniTAO/ANIR NIR upper limits
  78. GRB 101017A: miniTAO/ANIR NIR upper limits
  79. GRB 101017A: Swift XRT refined analysis
  80. GRB 101014A: Fermi LAT detection
  81. GRB 101014A: Fermi GBM detection
  82. GRB 101011A: XRT Refined Analysis
  83. GRB 101008A: Fermi GBM observation
  84. GRB 101008A: Swift-XRT refined analysis
  85. GRB 100728B: X-shooter redshift
  86. Refined analysis shows Swift Trigger 435520 is not a GRB
  87. GRB 100924A: Fermi GBM observation
  88. GRB 100915B: Fermi GBM observation
  89. GRB 100915A: Swift/UVOT Upper Limits
  90. GRB 100915A: Swift-XRT refined analysis
  91. GRB 100910A: Fermi GBM detection
  92. GRB 100909A: Swift-XRT refined analysis
  93. GRB 100901A: optical observation in Maidanak, break confirmation
  94. GRB 100909A: Swift target of opportunity observation
  95. GRB100906A: R band observations
  96. GRB 100906A: Fermi GBM observation
  97. GRB 100906A: TLS Monitoring
  98. GRB 100906A: Swift-XRT refined analysis
  99. GRB 100906A: TLS Multicolor Observations
  100. GRB 100901A: TLS observations, SDSS calibration, decay slope

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