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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"

18634 results found.

  1. GRB 070429B: Swift detection of a short burst
  2. GRB 070429: ROTSE-III Optical Limits
  3. GRB 070429: Swift detection of a burst
  4. GRB 070427, Swift-BAT Refined Analysis
  5. GRB 070427: Swift detection of a burst
  6. GRB070419B: Suzaku WAM observation of the prompt emission
  7. GRB 070411, deep LBT photometry
  8. GRB 070420: pseudo-z~1.56 from spectral parameters of the prompt
  9. GRB 070420 Swift-BAT Refined Analysis
  10. GRB070419A: Kuiper Optical detection
  11. GRB070419a: Swift UVOT observations
  12. GRB 070419A: MARGE Observations
  13. GRB 070420: optical rebrightening observed at Mt. John
  14. GRB 070420: Swift XRT refined analysis
  15. GRB070420: Swift UVOT continuing observations
  16. GRB 070420: Faulkes Telescope South Observations
  17. GBR 070419A: Swift/XRT refined analysis
  18. GRB 070420: TAROT La Silla observatory optical observations
  19. GRB 070420: NIR and optical afterglow confirmed
  20. GRB 070420: Swift detection of a burst with optical afterglow
  21. GRB 070419A: Early Super-LOTIS Observations
  22. GRB 070419B, Swift-BAT refined analysis
  23. GRB 070419A Swift-BAT Refined Analysis
  24. GRB 070419A: RAPTOR Detection of Early Emission
  25. GRB 070419B: Swift XRT refined analysis
  26. GRB 070419A, Optical observations
  27. GRB070419 - SDSS Pre-Burst Observations
  28. GRB 070419A: Faulkes Telescope North Optical Observations
  29. GRB 070419B optical afterglow candidate
  30. GRB 070419B: optical afterglow candidate
  31. GRB070419A, optical observation
  32. GRB070330: Correction to UVOT position
  33. GRB 070419B: Swift detection of a burst
  34. GRB 070419A: ROTSE-III Optical Limits
  35. GRB 070419: Swift detection of a burst
  36. Swift-BAT Trigger 276045 is a Cosmic Ray Shower event
  37. Trigger 276045: Swift detection of a possible burst
  38. GRB 070406: Swift XRT refined analysis
  39. GRB 070411: TLS data shows plateau, flares
  40. GRB070412: Swift UVOT observations
  41. GRB 070411: Swift/UVOT observations
  42. GRB 070412, Swift-BAT refined analysis
  43. GRB 070412: Swift-XRT refined analysis
  44. GRB 070411: Swift-XRT refined analysis
  45. GRB 070412: Optical observations at Crni Vrh
  46. GRB 070412: Swift-XRT refined position
  47. GRB 070411, Swift-BAT refined analysis
  48. GRB 070412: Swift detection of a burst
  49. GRB 070411: ROTSE-III Detection of Optical Counterpart
  50. GRB 070411: Tautenburg RRM Afterglow Confirmation
  51. GRB 070411: Swift detection of a burst with optical afterglow
  52. GRB 070406: Swift XRT team further analysis
  53. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  54. GRB 070406, Swift-BAT refined analysis
  55. GRB070406: Swift UVOT observations
  56. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  57. GRB 070406: SARA upper limit
  58. GRB 070406: Xinglong TNT optical Upper Limit
  59. GRB 070406: Swift detection of a burst
  60. INTEGRAL ToO Observation of SGR1806-20
  61. UVOT observations of GRB070330
  62. GRB 070330, Swift-BAT refined analysis
  63. GRB 070330: TAROT La Silla observatory optical observations
  64. GRB 070330: Swift-XRT refined analysis
  65. GRB 070330: Swift detection of a burst
  66. GRB 070328: pseudo-z~2.75 from spectral parameters of the prompt
  67. Konus-Wind observation of GRB 070328
  68. GRB 070328: Swift/UVOT Upper Limits
  69. GRB 070328: Swift/XRT Refined Analysis
  70. GRB 070328, Swift-BAT refined analysis
  71. GRB 070328: Swift detection of a burst
  72. GRB070318: Swift UVOT indicates unusual optical/UV afterglow
  73. GRB 070318: Gemini + Magellan spectra
  74. GRB070318: Swift UVOT continuing observations
  75. GRB070318: Swift-XRT refined analysis
  76. GRB 070318: Swift/UVOT Continued Observations
  77. GRB 070318, Swift-BAT refined analysis
  78. GRB 070318: Swift detection of a burst with an optical afterglow
  79. GRB 070311: Late Central Engine Activity Optical Flare??
  80. VLA observation of GRB 070311
  81. GRB 070309: variability of the XRT afterglow candidate
  82. GRB 070311: Swift/UVOT Upper Limits
  83. GRB 070311: Swift-XRT refined analysis
  84. GRB070309: Swift/XRT possible afterglow detection
  85. GRB 070125: Chandra X-ray Confirmation of Jet Break
  86. GRB 070309: Swift/UVOT Upper Limits
  87. Swift UVOT Finding Charts for GRB 070309
  88. GRB 070125: X-ray light curve analysis
  89. VLA observation of GRB 070306
  90. GRB 070306: NOT observations
  91. GRB 070306 Swift/UVOT refined analysis
  92. GRB 070306, Swift-BAT refined analysis
  93. GRB 070306: XRT Team Refined Analysis
  94. GRB070306 - SDSS Pre-burst Observations
  95. GRB 070306: Swift detection of a burst
  96. GRB070227: Swift-XRT refined analysis
  97. GRB 070125, deep late-time optical observation
  98. VLA observation of GRB 070224
  99. GRB 070227: optical observations
  100. GRB 070223: Optical Observations

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