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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').

17956 results found.

  1. GRB 070508, Swift-BAT refined analysis
  2. GRB 070508: Swift-XRT refined analysis
  3. GRB 070508: TAROT La Silla observatory optical observations
  4. GRB 070508: Swift detection of an intense burst with an optical counterpart
  5. GRB070412: MAGIC telescope GeV observation
  6. Swift-BAT trigger 278809 is not a GRB
  7. GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
  8. GRB070506: Swift/UVOT Observations
  9. GRB070506: Swift XRT refined analysis
  10. GRB 070506, Swift-BAT Refined Analysis
  11. GRB 070506: Swift detection of a burst with optical afterglow
  12. GRB 070429A: Swift XRT further analysis
  13. GRB 070309: Swift-XRT afterglow confirmation
  14. VLA observation of GRB 070429B
  15. Swift/UVOT observations of GRB070429B
  16. GRB 070429B, Swift-BAT refined analysis
  17. Swift/UVOT observations of GRB070429A
  18. GRB 070429A: Swift XRT refined analysis
  19. GRB 070429A, Swift-BAT refined analysis
  20. GRB 070429B: Swift XRT refined analysis
  21. GRB 070429B: ROTSE-III Optical Limits
  22. GRB 070429B: Swift detection of a short burst
  23. GRB 070429: ROTSE-III Optical Limits
  24. GRB 070429: Swift detection of a burst
  25. GRB 070427, Swift-BAT Refined Analysis
  26. GRB 070427: Swift detection of a burst
  27. GRB070419B: Suzaku WAM observation of the prompt emission
  28. GRB 070411, deep LBT photometry
  29. GRB 070420: pseudo-z~1.56 from spectral parameters of the prompt
  30. GRB 070420 Swift-BAT Refined Analysis
  31. GRB070419A: Kuiper Optical detection
  32. GRB070419a: Swift UVOT observations
  33. GRB 070419A: MARGE Observations
  34. GRB 070420: optical rebrightening observed at Mt. John
  35. GRB 070420: Swift XRT refined analysis
  36. GRB070420: Swift UVOT continuing observations
  37. GRB 070420: Faulkes Telescope South Observations
  38. GBR 070419A: Swift/XRT refined analysis
  39. GRB 070420: TAROT La Silla observatory optical observations
  40. GRB 070420: NIR and optical afterglow confirmed
  41. GRB 070420: Swift detection of a burst with optical afterglow
  42. GRB 070419A: Early Super-LOTIS Observations
  43. GRB 070419B, Swift-BAT refined analysis
  44. GRB 070419A Swift-BAT Refined Analysis
  45. GRB 070419A: RAPTOR Detection of Early Emission
  46. GRB 070419B: Swift XRT refined analysis
  47. GRB 070419A, Optical observations
  48. GRB070419 - SDSS Pre-Burst Observations
  49. GRB 070419A: Faulkes Telescope North Optical Observations
  50. GRB 070419B optical afterglow candidate
  51. GRB 070419B: optical afterglow candidate
  52. GRB070419A, optical observation
  53. GRB070330: Correction to UVOT position
  54. GRB 070419B: Swift detection of a burst
  55. GRB 070419A: ROTSE-III Optical Limits
  56. GRB 070419: Swift detection of a burst
  57. Swift-BAT Trigger 276045 is a Cosmic Ray Shower event
  58. Trigger 276045: Swift detection of a possible burst
  59. GRB 070406: Swift XRT refined analysis
  60. GRB 070411: TLS data shows plateau, flares
  61. GRB070412: Swift UVOT observations
  62. GRB 070411: Swift/UVOT observations
  63. GRB 070412, Swift-BAT refined analysis
  64. GRB 070412: Swift-XRT refined analysis
  65. GRB 070411: Swift-XRT refined analysis
  66. GRB 070412: Optical observations at Crni Vrh
  67. GRB 070412: Swift-XRT refined position
  68. GRB 070411, Swift-BAT refined analysis
  69. GRB 070412: Swift detection of a burst
  70. GRB 070411: ROTSE-III Detection of Optical Counterpart
  71. GRB 070411: Tautenburg RRM Afterglow Confirmation
  72. GRB 070411: Swift detection of a burst with optical afterglow
  73. GRB 070406: Swift XRT team further analysis
  74. SUBJECT: GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  75. GRB 070406, Swift-BAT refined analysis
  76. GRB070406: Swift UVOT observations
  77. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  78. GRB 070406: SARA upper limit
  79. GRB 070406: Xinglong TNT optical Upper Limit
  80. GRB 070406: Swift detection of a burst
  81. INTEGRAL ToO Observation of SGR1806-20
  82. UVOT observations of GRB070330
  83. GRB 070330, Swift-BAT refined analysis
  84. GRB 070330: TAROT La Silla observatory optical observations
  85. GRB 070330: Swift-XRT refined analysis
  86. GRB 070330: Swift detection of a burst
  87. GRB 070328: pseudo-z~2.75 from spectral parameters of the prompt
  88. Konus-Wind observation of GRB 070328
  89. GRB 070328: Swift/UVOT Upper Limits
  90. GRB 070328: Swift/XRT Refined Analysis
  91. GRB 070328, Swift-BAT refined analysis
  92. GRB 070328: Swift detection of a burst
  93. GRB070318: Swift UVOT indicates unusual optical/UV afterglow
  94. GRB 070318: Gemini + Magellan spectra
  95. GRB070318: Swift UVOT continuing observations
  96. GRB070318: Swift-XRT refined analysis
  97. GRB 070318: Swift/UVOT Continued Observations
  98. GRB 070318, Swift-BAT refined analysis
  99. GRB 070318: Swift detection of a burst with an optical afterglow
  100. GRB 070311: Late Central Engine Activity Optical Flare??

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