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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"

4613 results found.

  1. GRB 090927: Swift XRT refined analysis
  2. GRB 090926B: Swift XRT refined analysis
  3. GRB 090926A: Skynet/PROMPT Discovery of the Optical Afterglow
  4. GRB 090823: Swift XRT confirmation of the X-ray afterglow
  5. GRB 090902B: Suzaku WAM observation of the prompt emission
  6. GRB 090904B: Fermi GBM detection
  7. GRB 090904A: Swift-XRT refined analysis
  8. GRB 090904B: Swift XRT Refined Analysis
  9. GRB 090904B: Swift detection of a burst
  10. GRB 090831C: Swift XRT Refined Analysis
  11. GRB 090831: MAXI GSC detection
  12. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  13. GRB 090817: aphotometry of USNO-B1.0 341-0096763
  14. GRB 090815B: Fermi GBM detection
  15. GRB 090814B: Swift-XRT detection of a possible afterglow.
  16. GRB 090814A: Swift-XRT Team Refined Analysis
  17. GRB 090813: Swift-XRT refined analysis
  18. GRB 090812: Swift XRT refined analysis
  19. GRB 090809: Swift-XRT refined analysis
  20. GRB 090807: Liverpool Telescope observations
  21. GRB 090807: Swift-XRT refined analysis
  22. Swift trigger 358760 is probably a noise event
  23. GRB 090727: Swift-XRT refined analysis
  24. GRB 090715B: Late-time Lick 3m observations
  25. GRB 090726: Swift-XRT Team refined analysis
  26. GRB 090720: Fermi GBM detection
  27. GRB 090715B: Swift XRT Refined Analysis
  28. GRB 090621B: MTM-500 optical observations
  29. GRB 090709B: Fermi GBM detection
  30. GRB 090709A: Quasiperiodic variations in the BAT light curve
  31. GRB 090709A: NOT optical observations
  32. GRB 090709A: Swift XRT Refined Analysis
  33. GRB 090529: CrAO optical upper limit
  34. GRB 090529: Mt.Terskol optical observations
  35. GRB 090630: Fermi GBM detection
  36. Konus-Wind observation of GRB 090626
  37. GRB 090625B: Swift-XRT refined analysis
  38. GRB 090625B: Swift observation of the INTEGRAL GRB 090625B
  39. GRB 090625: Fermi GBM detection
  40. GRB 090621B: Swift-XRT refined analysis
  41. GRB 090621: Swift-XRT Team refined analysis
  42. GRB 090621: Swift detection of a burst
  43. GRB090618: Swift-XRT team refined analysis
  44. GRB 090618: planned XMM-Newton observation
  45. GRB 090530: break in light curve
  46. GRB 090529: optical observations
  47. GRB 090529: TLS Afterglow Observations
  48. GRB090529: UVOT/Swift detection of a brightening optical afterglow
  49. GRB 090524: Fermi GBM detection
  50. GRB 090519: Swift-XRT refined analysis
  51. GRB 090518: Swift-XRT refined analysis
  52. GRB 090516: Swift XRT refined analysis
  53. GRB 090509 - Zadko Telescope observations
  54. GRB 090510: UVOT refined analysis
  55. GRB 090510: Swift XRT refined analysis
  56. GRB 090510: Swift detection of a short hard burst
  57. GRB 090509: Swift detection of a burst
  58. GRB 090424: optical observations
  59. GRB 090429B: Swift XRT refined analysis
  60. GRB 090426: GAO 150cm telescope Optical Observation
  61. GRB 090423: millimeter detection
  62. GRB 090426: Swift-XRT refined analysis
  63. GRB 090424 : Lulin 1m telescope optical observations
  64. GRB 090424: THO optical observations
  65. GRB090423: Y-band limit
  66. GRB 090424 optical observations
  67. GRB 090424: Swift-XRT refined analysis
  68. GRB 090424: Fermi GBM Observation
  69. GRB 090423: Swift-XRT refined analysis
  70. GRB090418A Rc-band photometry
  71. GRB090423, RIMOTS optical upper limits
  72. GRB 090418A: optical observations
  73. GRB 090418A: Swift/UVOT Observations
  74. GRB 090419: Swift-XRT refined analysis
  75. VLA radio detection of GRB 090418
  76. GRB 090418: Swift XRT refined analysis
  77. GRB 090418: Swift-BAT refined analysis
  78. GRB 090418: Enhanced Swift-XRT position
  79. GRB 090418: Swift detection of a burst with optical afterglow
  80. GRB 090418 OA candidate
  81. GRB 090408b: IPN Triangulation
  82. GRB 090328b: IPN Triangulation
  83. GRB 090407: GROND upper limits
  84. GRB 090407: Swift-XRT refined analysis
  85. GRB 090404: Swift-XRT Team refined analysis
  86. GRB 090401A: Suzaku WAM observation of the prompt emission
  87. GRB 090401B: Swift XRT Refined Analysis
  88. GRB 090328: Radio afterglow detection
  89. GRB 090328B: Fermi GBM Detection
  90. GRB 090328: GROND Detection of the Optical/NIR Afterglow
  91. GRB 090323: WSRT Radio Detection
  92. GRB 090327: Fermi GBM detection
  93. GRB 090320B: MASTER-Net prompt optical observations
  94. GRB 090323: Swift-XRT refined analysis
  95. GRB 090324: SuperAGILE Localization of a Long GRB
  96. GRB 090323 Gemini-South Redshift
  97. GRB 090323: P60 Afterglow Confirmation
  98. GRB 090323: GROND Detection of the Afterglow and Photo-z
  99. SGR J1550-5418: two Fermi GBM triggers on March 22
  100. GRB 090319: Fermi GBM detection

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