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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"

27017 results found.

  1. GRB 090515: Swift detection of a short burst
  2. GRB 090510: Suzaku WAM observation of the prompt emission
  3. GRB 090510: Swift/UVOT host galaxy candidates
  4. GRB 090510: Fermi-LAT follow-up analysis
  5. GRB 090509, further Swift-BAT refined analysis
  6. Fermi Gamma-ray Burst Monitor trigger 263649437 is not a GRB
  7. GRB 090510B: Fermi GBM detection
  8. GRB 090502: Fermi GBM detection
  9. Konus-Wind observation of GRB 090510
  10. GRB 090510: UVOT refined analysis
  11. GRB 090510: Swift XRT refined analysis
  12. GRB 090510: Swift-BAT refined analysis
  13. GRB 090510: Fermi GBM detection
  14. GRB 090509: Swift-BAT refined analysis
  15. Fermi LAT detection of GRB 090510
  16. GRB 090510: Swift/UVOT Detection of a Candidate Optical Afterglow
  17. GRB 090510: Swift detection of a short hard burst
  18. GRB 090408: optical upper limit
  19. GRB 090509: GROND further analysis and redshift limit
  20. GRB 090509: GROND afterglow candidate
  21. GRB 090509: Swift detection of a burst
  22. GRB 090323: optical observations
  23. GRB 090424: optical observations
  24. GRB 090429A: ROVOR magnitude limit
  25. GRB 090428B: Suzaku WAM observation of the prompt emission
  26. GRB 090426: optical observations
  27. GRB 090429D: Fermi GBM detection
  28. GRB 090429C: Fermi GBM detection
  29. GRB 090429B: Swift/UVOT Upper Limits
  30. GRB 090429A: Swift/UVOT Upper Limits
  31. GRB 090424: YNAO-GMG observations
  32. GRB 090429A: GROND upper limits
  33. GRB 090427C: Fermi GBM detection
  34. GRB 090427B: Fermi GBM detection
  35. GRB 090426C: Fermi GBM detection
  36. GRB 090426B: Fermi GBM detection/observation
  37. GRB 090429B: Swift XRT refined analysis
  38. GRB 090428B: Fermi GBM detection
  39. GRB 090428: Fermi GBM detection
  40. GRB 090426: GAO 150cm telescope Optical Observation
  41. GRB 090429B: RIMOTS optical upper limits
  42. GRB 090429B: Swift-BAT refined analysis
  43. GRB 090429A: Swift-BAT refined analysis
  44. GRB 090426: YNAO-GMG observations
  45. GRB 090429B: GROND Observations
  46. GRB 090429B: Super-LOTIS early observations
  47. GRB 090429B: Swift detection of a burst
  48. GRB 090429: Swift detection of a burst
  49. GRB 090425: Fermi GBM detection
  50. GRB 090424: Suzaku WAM observation of the prompt emission
  51. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  52. GRB090426 Swift/UVOT observations
  53. GRB 090426 Keck LRIS redshift
  54. GRB 090426: Swift-BAT refined analysis
  55. GRB 090426: Swift-XRT refined analysis
  56. GRB 090423: GROND second epoch imaging and refined SED
  57. GRB 090426, RIMOTS optical upper limits
  58. GRB 090426: TNT confimation of optical counterpart
  59. GRB 090426: Swift detection of a burst with an optical counterpart
  60. GRB 090424: MASTER-Net prompt optical limit
  61. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  62. GRB 090424 Gemini-South Redshift
  63. GRB 090424 : TAOS optical detection
  64. GRB 090424: Swift-XRT refined analysis
  65. Swift/UVOT observations of GRB 090424
  66. GRB 090424: Swift-BAT refined analysis
  67. GRB 090424: Fermi GBM Observation
  68. GRB 090423: Fermi GBM observation
  69. GRB 090422: Fermi GBM observation
  70. GRB 090424: TNT optical observations
  71. GRB 090424: ROTSE-III Confimation of Optical Counterpart
  72. GRB 090424: Swift detection of a burst with an optical counterpart
  73. GRB 090423 limiting magnitudes
  74. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  75. GRB 090423: GROND detection and preliminary photo-z
  76. GRB 090423: NOT z-band limit
  77. GRB 090423: Swift-XRT refined analysis
  78. GRB090418A Rc-band photometry
  79. GRB090423 - Swift/UVOT upper limits.
  80. GRB 090422: Swift-XRT refined analysis
  81. GRB090423, RIMOTS optical upper limits
  82. GRB 090423: Swift-BAT refined analysis
  83. GRB 090422: Swift/UVOT Upper Limits
  84. GRB 090423: Faulkes Telescope South observations
  85. GRB 090423: Swift detection of a burst
  86. GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis
  87. GRB 090422: Swift-BAT refined analysis
  88. GRB 080410: GAO 150cm telescope Optical Observation
  89. GRB 080408A: GAO 150cm telescope Optical Observation
  90. GRB 090422: Liverpool Telescope observations
  91. GRB 090418B: Suzaku WAM observation of the prompt emission
  92. GRB 090422: Swift detection of a burst
  93. GRB 090418C: Fermi GBM Detection
  94. Swift-BAT trigger 349718 is not a burst
  95. GRB 090419: Swift/UVOT Observations
  96. GRB 090418A: Swift/UVOT Observations
  97. GRB 090417B: Swift/UVOT Upper Limits
  98. GRB 090419: Swift-XRT refined analysis
  99. GRB 090419: GROND detection of afterglow candidate
  100. GRB 090419: Swift-BAT refined analysis

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