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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"

27415 results found.

  1. GRB 090510: Swift-BAT refined analysis
  2. GRB 090510: Fermi GBM detection
  3. GRB 090509: Swift-BAT refined analysis
  4. Fermi LAT detection of GRB 090510
  5. GRB 090510: Swift/UVOT Detection of a Candidate Optical Afterglow
  6. GRB 090510: Swift detection of a short hard burst
  7. GRB 090408: optical upper limit
  8. GRB 090509: GROND further analysis and redshift limit
  9. GRB 090509: REM NIR afterglow
  10. GRB 090509: GROND afterglow candidate
  11. GRB 090509: Swift detection of a burst
  12. GRB 090323: optical observations
  13. GRB 090424: optical observations
  14. GRB 090429A: ROVOR magnitude limit
  15. GRB 090428B: Suzaku WAM observation of the prompt emission
  16. GRB 090426: optical observations
  17. GRB 090429D: Fermi GBM detection
  18. GRB 090429C: Fermi GBM detection
  19. GRB 090429B: Swift/UVOT Upper Limits
  20. GRB 090429A: Swift/UVOT Upper Limits
  21. GRB 090424: YNAO-GMG observations
  22. GRB 090429A: GROND upper limits
  23. GRB 090427C: Fermi GBM detection
  24. GRB 090427B: Fermi GBM detection
  25. GRB 090426C: Fermi GBM detection
  26. GRB 090426B: Fermi GBM detection/observation
  27. GRB 090429B: Swift XRT refined analysis
  28. GRB 090428B: Fermi GBM detection
  29. GRB 090428: Fermi GBM detection
  30. GRB 090426: GAO 150cm telescope Optical Observation
  31. GRB 090429B: RIMOTS optical upper limits
  32. GRB 090429B: Swift-BAT refined analysis
  33. GRB 090429A: Swift-BAT refined analysis
  34. GRB 090426: YNAO-GMG observations
  35. GRB 090429B: GROND Observations
  36. GRB 090429B: Super-LOTIS early observations
  37. GRB 090429B: Swift detection of a burst
  38. GRB 090429: Swift detection of a burst
  39. GRB 090423: pseudo burst at z=1 and its relation to GRB 080913
  40. GRB 090426: Swift/BAT spectral lag results
  41. GRB 090425: Fermi GBM detection
  42. GRB 090424: Suzaku WAM observation of the prompt emission
  43. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  44. GRB090426 Swift/UVOT observations
  45. GRB 090426 Keck LRIS redshift
  46. GRB 090426: Swift-BAT refined analysis
  47. GRB 090426: Swift-XRT refined analysis
  48. GRB 090423: GROND second epoch imaging and refined SED
  49. GRB 090426, RIMOTS optical upper limits
  50. GRB 090426: TNT confimation of optical counterpart
  51. GRB 090426: Swift detection of a burst with an optical counterpart
  52. GRB 090424: MASTER-Net prompt optical limit
  53. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  54. GRB 090424 Gemini-South Redshift
  55. GRB 090423: Swift/BAT spectral lag results
  56. GRB 090424 : TAOS optical detection
  57. GRB 090424: Swift-XRT refined analysis
  58. Swift/UVOT observations of GRB 090424
  59. GRB 090424: Swift-BAT refined analysis
  60. GRB 090424: Fermi GBM Observation
  61. GRB 090423: Fermi GBM observation
  62. GRB 090422: Fermi GBM observation
  63. GRB 090423: Ep,i - Eiso correlation
  64. GRB 090424: TNT optical observations
  65. GRB 090424: ROTSE-III Confimation of Optical Counterpart
  66. GRB 090424: Swift detection of a burst with an optical counterpart
  67. GRB 090423 limiting magnitudes
  68. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  69. GRB 090423: GROND detection and preliminary photo-z
  70. GRB 090423: NOT z-band limit
  71. GRB 090423: Swift-XRT refined analysis
  72. GRB090418A Rc-band photometry
  73. GRB090423 - Swift/UVOT upper limits.
  74. GRB 090422: Swift-XRT refined analysis
  75. GRB090423, RIMOTS optical upper limits
  76. GRB 090423: Swift-BAT refined analysis
  77. GRB 090422: Swift/UVOT Upper Limits
  78. GRB 090423: Faulkes Telescope South observations
  79. GRB 090423: Swift detection of a burst
  80. GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis
  81. GRB 090422: Swift-BAT refined analysis
  82. GRB 090418B: RTT150 optical observations
  83. GRB 080410: GAO 150cm telescope Optical Observation
  84. GRB 080408A: GAO 150cm telescope Optical Observation
  85. GRB 090422: Liverpool Telescope observations
  86. GRB 090422: Swift detection of a burst
  87. GRB 090418C: Fermi GBM Detection
  88. Swift-BAT trigger 349718 is not a burst
  89. GRB 090418B: GRAS002 observatios
  90. GRB 090417B: Optical observation
  91. GRB 090418B: GROND observations
  92. GRB 090419: Swift/UVOT Observations
  93. GRB 090418B: Faulkes Telescope North observations
  94. GRB 090418A: Swift/UVOT Observations
  95. GRB 090417B: Swift/UVOT Upper Limits
  96. GRB 090417B Correction to the BAT refined analysis position
  97. GRB 090419: Swift-XRT refined analysis
  98. Konus-Wind observation of GRB 090418B
  99. GRB 090419: GROND detection of afterglow candidate
  100. GRB 090419: Swift-BAT refined analysis

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