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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').

18318 results found.

  1. GRB 060507: Swift detection of a burst
  2. GRB060505: Swift/UVOT Observations
  3. GRB 060505: Swift XRT Team Refined Analysis
  4. GRB 060505: Swift XRT afterglow canditate position
  5. GRB 060505: Swift-BAT detection of a weak burst
  6. GRB 060502B MDM Follow-up Observation
  7. GRB060502A, optical observation
  8. GRB 060502B: Swift/UVOT upper limits
  9. GRB 060502A: Swift/UVOT source detection
  10. GRB 060502B: MDM Optical Observation
  11. GRB 060502B: Refined analysis of the Swift-BAT short burst
  12. GRB060502B: Swift XRT Team refined analysis
  13. GRB060502B: correction to XRT position
  14. GRB 060502B: MASTER optical observations
  15. GRB 060502B: Swift detection of a short burst
  16. GRB060502: Swift-XRT refined analysis
  17. GRB 060502: Swift-BAT refined analysis
  18. GRB 060502: APO Spectroscopic Observations
  19. GRB060501: Swift UVOT followup observations
  20. GRB060502: Super-LOTIS Observations
  21. GRB 060502: Swift detection of a burst with an optical counterpart
  22. GRB 060501: MDM Observations
  23. GRB060501: Super-LOTIS observations
  24. GRB060501: P60 imaging and afterglow candidate
  25. GRB 060501: Refined analysis of the Swift-BAT burst
  26. GRB060501: Swift XRT position
  27. GRB 060501: ROTSE-III Optical Limits
  28. GRB 060501: Swift detection of a burst
  29. GRB060428B: optical observation
  30. GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
  31. GRB 060428B: MDM Observations
  32. GRB060428B: Swift XRT Team refined analysis
  33. GRB 060427B: IPN localization of a short hard burst
  34. GRB 060428B: Refined analysis of the Swift-BAT burst
  35. GRB 060428B: KAIT observations
  36. GRB060428A: Swift/UVOT observations.
  37. GRB060428B, optical observation
  38. GRB 060428A: Refined analysis of the Swift-BAT burst
  39. GRB060428A: Swift XRT Team refined analysis
  40. GRB 060428B: Swift detection of a burst
  41. GRB 060428: Swift detection of a burst
  42. GRB 060427: NOT observations
  43. GRB 060427: Swift/UVOT upper limits.
  44. GRB 060427: Refined analysis of the Swift-BAT burst
  45. GRB060427: Swift XRT Team refined analysis
  46. GRB060418: Swift XRT Team Further Refined Analysis
  47. GRB 060427, optical observation
  48. GRB 060427: Swift detection of a burst
  49. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  50. GRB 060424: Refined analysis of the Swift-BAT burst
  51. GRB 060424: Swift detection of a burst
  52. Swift-BAT detection of Mrk 421
  53. GRB060421: Swift/UVOT observations
  54. GRB 060421: Swift-BAT Refined Analysis
  55. GRB 060421: Swift-XRT refined analysis
  56. GRB 060418: prediction of t_break
  57. Konus-Wind observation of GRB 060418
  58. GRB(?)060421:MASTER optical limit
  59. GRB(?)060421 : XRT position
  60. Possible GRB060421: BART limits
  61. GRB(?) 060421: Swift detection of a burst
  62. GRB060418: Swift/UVOT Observations
  63. GRB 060418: FRAM early afterglow observation
  64. GRB 060418: Refined Analysis of the Swift-BAT burst
  65. VLT/UVES observations of GRB060418
  66. GRB060418: Swift XRT Team Refined Analysis
  67. GRB060418: Magellan/MIKE Spectroscopic Redshift
  68. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  69. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  70. GRB060413: Swift/UVOT upper limits
  71. SGR 1900+14: Swift detection of an outburst
  72. GRB 060413: Refined analysis of the Swift-BAT burst
  73. GRB 060413: XRT refined analysis
  74. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  75. GRB 060413: Swift detection of a burst
  76. GRB060403: XRT refined analysis
  77. GRB 060403: Swift/UVOT upper limits
  78. SGR 1900+14: BAT observations
  79. GRB 060403: Refined analysis of the Swift-BAT burst
  80. GRB060403: Swift XRT refined position
  81. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  82. GRB 060403: Swift detection of a burst
  83. GRB060331: Swift/UVOT upper limits
  84. Swift XRT observations of the HETE transient H4043
  85. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  86. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  87. SGR 1900+14: Swift-BAT detection of a bright outburst
  88. GRB 060323 : WIDGET simultaneous optical observations
  89. GRB 060322: Confirmation of Swift XRT afterglow
  90. GRB060323: optical limit
  91. SGR 1900+14: CORRECTION to GCN 4923
  92. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  93. SGR 1900+14: Swift detection of renewed activity
  94. GRB060323: NOT optical observations
  95. GRB 060322: IAC80 optical observations
  96. GRB 060322: Swift XRT afterglow candidate
  97. GRB 060323: Swift/UVOT Observations
  98. GRB060323: NOT observations
  99. GRB 060323: Refined analysis of the Swift-BAT burst
  100. GRB 060323: Swift XRT refined analysis

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