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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"

45452 results found.

  1. GRB 090809: Swift-XRT refined analysis
  2. GRB090809: Swift/UVOT observations
  3. GRB 090809: Enhanced Swift-XRT position
  4. GRB 090809: Swift-BAT refined analysis
  5. GRB 090809: afterglow confirmation at the NOT
  6. GRB 090809: Swift detection of a burst with a possible optical counterpart
  7. GRB 090807: Liverpool Telescope observations
  8. GRB 090807: MITSuME optical upper limit
  9. GRB 090807: Swift/UVOT Upper Limits
  10. GRB 090807: Swift-XRT refined analysis
  11. GRB 090807, Swift-BAT refined analysis
  12. GRB 090807: Enhanced Swift-XRT position
  13. GRB 090807, RIMOTS optical upper limits
  14. GRB 090807: Swift detection of a burst
  15. Fermi Gamma-ray Burst Monitor trigger 271275771 is not a GRB
  16. GRB 090802B: Fermi GBM detection
  17. IPN Triangulation and Konus-Wind observaions of GRB090727B
  18. GRB 090802: Fermi GBM detection
  19. GRB 090726: optical observation
  20. Swift-BAT trigger 358760 is most likely not a GRB
  21. Swift trigger 358760 is probably a noise event
  22. GRB 090717A: Suzaku WAM observation of the prompt emission
  23. GRB 090709A : Quick look analysis of the Suzaku observation
  24. GRB 090728: Swift-BAT refined analysis
  25. GRB 090727: GRT Optical Observation
  26. GRB 090728: Swift XRT refined analysis
  27. GRB 090727: optical observations
  28. GRB 090726: GRT Optical Observation
  29. GRB 090727: Swift/UVOT Upper Limits
  30. GRB 090728: Swift/UVOT Upper Limits
  31. GRB 090728: Enhanced Swift-XRT position
  32. GRB 090727: I-band observations from 1.23m CAHA
  33. GRB 090728, RIMOTS optical upper limits
  34. GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
  35. GRB 090728: Swift detection of a burst
  36. GRB 090727: Swift-BAT refined analysis
  37. GRB 090727: Swift-XRT refined analysis
  38. GRB 090727: Liverpool Telescope Afterglow Confirmation and Optical Flare
  39. GRB 090727: Enhanced Swift-XRT position
  40. GRB 090715B: Late-time Lick 3m observations
  41. GRB 090727: Liverpool Telescope possible OT candidate
  42. GRB 090727: Swift detection of a burst
  43. GRB090726: Swift/UVOT observations
  44. GRB 090726, Swift-BAT refined analysis
  45. GRB 090726: Afterglow candidate photometryfrom Crni Vrh
  46. GRB 090726: D50 optical observations
  47. GRB 090711: Fermi GBM detection
  48. GRB090726: 6-meter telescope redshift
  49. GRB 090726: Swift-XRT Team refined analysis
  50. GRB 090726: Enhanced Swift-XRT position
  51. GRB 090726: optical transient candidate
  52. GRB 090726: Swift/UVOT Finding Chart Observation
  53. GRB 090726: Swift-XRT position of probable counterpart
  54. GRB 090726: Swift detection of a burst
  55. Swift Trigger 358354 is not a GRB
  56. Konus-Wind and Konus-RF observations of GRB 090719
  57. Konus-RF and Konus-Wind observations of GRB 090718B
  58. Fermi Gamma-ray Burst Monitor triggers 269935914 through 270021937 are not GRBs
  59. Konus-Wind observations of bright hard GRB 090720B
  60. IPN Triangulation of bright GRB 090720B
  61. GRB 090720: Gemini-North Imaging and Optical Afterglow
  62. GRB 090720B: Fermi GBM detection
  63. Swift XRT and UVOT refned analysis of GRB 090720
  64. GRB 090709A: Swift XRT Timing Analysis
  65. GRB 090715B: VLA radio detection
  66. GRB 090720 Source found in ground processing of Swift-BAT data
  67. GRB 090717B: Fermi GBM detection
  68. GRB 090717: Fermi GBM detection
  69. GRB 090719: Fermi GBM detection
  70. GRB 090718B: Fermi GBM detection
  71. GRB 090718: Fermi GBM detection
  72. GRB 090720: Fermi GBM detection
  73. GRB 090715B: further NOT optical observations
  74. GRB 090715A: Suzaku WAM observation of the prompt emission
  75. GRB 090709A - CARMA mm Observations
  76. GRB 090715B: Lick observations
  77. GRB 090715A: VLA observations
  78. Konus-Wind observations of short/hard GRB 090715A
  79. GRB 090715B: MASTER optical limit
  80. GRB 090715A: Swift-BAT refined analysis
  81. Konus-Wind and Konus-RF observations of GRB 090715B
  82. GRB 090715B: Swift/UVOT followup observations
  83. GRB 090715B: break in the optical afterglow decay
  84. GRB 090715B: Enhanced Swift-XRT position
  85. GRB 090715B: Observation of the optical afterglow
  86. GRB 090715B: Swift XRT Refined Analysis
  87. GRB090715B: WHT redshift
  88. GRB 090715B: Swift-BAT refined analysis
  89. GRB 090715B: NOT optical observations
  90. GRB 090715B: Swift detection of a burst with a possible optical counterpart
  91. GRB 090715A: ROTSE-III Optical Limits
  92. GRB 090715: Swift detection of a short hard burst
  93. Detection of GRB 090618 by RT-2 Experiment onboard the CORONAS-PHOTON Satellite
  94. Swift satellite anomaly
  95. GRB090713 optical limit by "Pi of the Sky"
  96. GRB 090712: Fermi GBM observation
  97. GRB 090713: Fermi GBM detection
  98. GRB 090712: Swift-BAT refined analysis
  99. GRB 090712: Swift detection of a burst
  100. GRB 090709A: Xinglong TNT optical upper limit

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