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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').

18174 results found.

  1. GRB 050402: Early observations with Swift-UVOT
  2. Swift Trigger 113225: P60 Observations
  3. GRB050401: ROTSE-III Detection of Prompt Optical Counterpart
  4. GRB 050401: Optical afterglow candidate
  5. Swift-BAT detection of GRB 050401
  6. GRB 050401: Prompt XRT position
  7. Retraction of three Swift GRB triggers
  8. Swift-BAT detection of GRB 050331b
  9. GRB 050331: Swift UVOT Source
  10. Swift-BAT detection of GRB 050331
  11. GRB 050331: Swift XRT Position
  12. Swift Data Publicly Available Starting April 5, 2005
  13. Konus-Wind observation of GRB 050326
  14. GRB050326: optical limit
  15. GRB 050326: Early observations with Swift-UVOT
  16. GRB 050326 XMM-Newton observation
  17. GRB 050326 : Planned XMM-Newton observation
  18. GRB 050326: Swift XRT Position
  19. GRB050326: optical limit 33min before GRB
  20. GRB 050326 BAT refined analysis
  21. GRB050326: delayed XRT observation
  22. Swift-BAT detection of a bright GRB 050326
  23. GRB050319, optical observations
  24. GRB050319, color indices
  25. GRB050319: RTT150 Optical Observations
  26. Swift-BAT detection of a bright outburst from SGR1806-20
  27. Swift-BAT trigger 112060 is not a real GRB
  28. GRB 050319: ROTSE-III Refined Analysis
  29. GRB 050318: Swift-BAT refined analysis
  30. Refined Swift XRT positions for GRB050315, GRB050318 and GRB050319
  31. GRB 050319 R band observations
  32. GRB 050319: Swift-UVOT detection of the afterglow
  33. GRB 050315: Variability Analysis of Swift BAT Time History
  34. GRB050319: BR optical photometry
  35. GRB 050318: SWIFT-UVOT refined analysis
  36. GRB 050319: Swift-BAT refined analysis
  37. GRB050319,optical observation
  38. Swift Detection of GRB 050319
  39. GRB 050319: Detection of Possible Optical Counterpart
  40. GRB 050318: Swift/UVOT detection of afterglow emission
  41. GRB050318: Swift XRT position
  42. Swift-BAT detection of GRB 050318
  43. GRB050223: analysis of the XMM-Newton observation
  44. GRB 050306: ROTSE-III early limits
  45. GRB 050315: Swift-BAT further refined analysis
  46. GRB050315: Swift-BAT Refined analysis
  47. Non-detection of GRB050315 in ATCA Radio Observations
  48. GRB 050315: Swift XRT Position
  49. GRB 050315: Early Observations with Swift/UVOT
  50. Swift-BAT detection of GRB 050315
  51. GRB050223: No XMM-Newton OM detection of afterglow emission
  52. GRB050309: CONCAM pre-trigger and trigger coincident optical
  53. GRB 050126: Redshift determination
  54. Swift-BAT trigger 107873: No Swift XRT counterpart
  55. GRB 050306: Confirmation of X-ray afterglow
  56. GRB 050309, Early optical limits from RAPTOR
  57. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  58. GRB 050309 : Lulin R-band observation
  59. Swift 107873: P60 Optical Observations
  60. GRB 050306: CORRECTION to date of observation
  61. GRB 050306: No Swift UVOT Optical Counterpart Detected
  62. GRB 050306: Possible X-ray Afterglow Position from the Swift
  63. Swift trigger 107518: optical observation
  64. GRB 050306,optical observation
  65. GRB 050306: Swift-BAT detection of a long burst
  66. GRB050215B: Late-Time Swift UVOT Observations
  67. PROMPT VRcIc Observations of GRB 050223
  68. GRB 050223: optical observations
  69. GRB050223 XMM-Newton observation
  70. INTEGRAL detection of GRB 050223
  71. GRB050223: No Swift UVOT Detection of Afterglow Emission
  72. GRB050223: ROTSE-III Optical Observations
  73. GRB 050223 Swift/BAT detection of a burst
  74. GRB 050223: Swift XRT Position
  75. GRB050219b: CORRECTION to time of UVOT observations
  76. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  77. GRB 050219b: CORRECTION to refined XRT position
  78. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  79. GRB 050219b: Refined XRT position
  80. GRB 050219b: Swift-BAT detection of a burst
  81. GRB 050219b: CORRECTION: Swift XRT Position
  82. GRB 050219b: Swift XRT Position
  83. GRB 050219a, optical observations
  84. GRB 050219a: Refined XRT position
  85. GRB050219a: No Swift UVOT Detection of Afterglow Emission
  86. GRB 050219: Swift-BAT detection of a burst
  87. GRB050215b: Swift UVOT Detection of Afterglow Emission
  88. GRB 050219: Prompt X-ray position
  89. GRB 050215b: XRT confirmation of IR afterglow candidate
  90. GRB050215b: P60 Optical Observations
  91. GRB 050215b: Swift XRT Source Variability
  92. GRB 050215B: candidate afterglow
  93. GRB 050215b : Lulin follow-up observation
  94. GRB 050215b, BOOTES-2 simultaneous optical observations
  95. GRB 050215B: UKIRT K-band imaging
  96. GRB 050215b: Swift XRT Observations
  97. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  98. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  99. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  100. GRB050215B: ROTSE-III optical observations

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