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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').

18345 results found.

  1. GRB 050319: Swift-UVOT detection of the afterglow
  2. GRB 050315: Variability Analysis of Swift BAT Time History
  3. GRB050319: BR optical photometry
  4. GRB 050318: SWIFT-UVOT refined analysis
  5. GRB 050319: Swift-BAT refined analysis
  6. GRB050319,optical observation
  7. Swift Detection of GRB 050319
  8. GRB 050319: Detection of Possible Optical Counterpart
  9. GRB 050318: Swift/UVOT detection of afterglow emission
  10. GRB050318: Swift XRT position
  11. Swift-BAT detection of GRB 050318
  12. GRB050223: analysis of the XMM-Newton observation
  13. GRB 050306: ROTSE-III early limits
  14. GRB 050315: Swift-BAT further refined analysis
  15. GRB050315: Swift-BAT Refined analysis
  16. Non-detection of GRB050315 in ATCA Radio Observations
  17. GRB 050315: Swift XRT Position
  18. GRB 050315: Early Observations with Swift/UVOT
  19. Swift-BAT detection of GRB 050315
  20. GRB050223: No XMM-Newton OM detection of afterglow emission
  21. GRB050309: CONCAM pre-trigger and trigger coincident optical
  22. GRB 050126: Redshift determination
  23. Swift-BAT trigger 107873: No Swift XRT counterpart
  24. GRB 050306: Confirmation of X-ray afterglow
  25. GRB 050309, Early optical limits from RAPTOR
  26. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  27. GRB 050309 : Lulin R-band observation
  28. Swift 107873: P60 Optical Observations
  29. GRB 050306: CORRECTION to date of observation
  30. GRB 050306: No Swift UVOT Optical Counterpart Detected
  31. GRB 050306: Possible X-ray Afterglow Position from the Swift
  32. Swift trigger 107518: optical observation
  33. GRB 050306,optical observation
  34. GRB 050306: Swift-BAT detection of a long burst
  35. GRB050215B: Late-Time Swift UVOT Observations
  36. PROMPT VRcIc Observations of GRB 050223
  37. GRB 050223: optical observations
  38. GRB050223 XMM-Newton observation
  39. INTEGRAL detection of GRB 050223
  40. GRB050223: No Swift UVOT Detection of Afterglow Emission
  41. GRB050223: ROTSE-III Optical Observations
  42. GRB 050223 Swift/BAT detection of a burst
  43. GRB 050223: Swift XRT Position
  44. GRB050219b: CORRECTION to time of UVOT observations
  45. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  46. GRB 050219b: CORRECTION to refined XRT position
  47. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  48. GRB 050219b: Refined XRT position
  49. GRB 050219b: Swift-BAT detection of a burst
  50. GRB 050219b: CORRECTION: Swift XRT Position
  51. GRB 050219b: Swift XRT Position
  52. GRB 050219a, optical observations
  53. GRB 050219a: Refined XRT position
  54. GRB050219a: No Swift UVOT Detection of Afterglow Emission
  55. GRB 050219: Swift-BAT detection of a burst
  56. GRB050215b: Swift UVOT Detection of Afterglow Emission
  57. GRB 050219: Prompt X-ray position
  58. GRB 050215b: XRT confirmation of IR afterglow candidate
  59. GRB050215b: P60 Optical Observations
  60. GRB 050215b: Swift XRT Source Variability
  61. GRB 050215B: candidate afterglow
  62. GRB 050215b : Lulin follow-up observation
  63. GRB 050215b, BOOTES-2 simultaneous optical observations
  64. GRB 050215B: UKIRT K-band imaging
  65. GRB 050215b: Swift XRT Observations
  66. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  67. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  68. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  69. GRB050215B: ROTSE-III optical observations
  70. GRB050215A: ROTSE-III Optical Observations
  71. short/hard GRB 050202, optical observations
  72. GRB 050128: Radio observations
  73. Further analysis of the short Swift-BAT GRB 050202
  74. GRB 050202: Second epoch radio observations
  75. GRB050202: Radio Observations
  76. GRB 050202: Short burst detected by Swift-BAT
  77. SGR1806-20: Swift-BAT detection of a large normal burst
  78. GRB050128: Faulkes Telescope South observations
  79. GRB050128,optical observations
  80. GRB050126: Updated Swift XRT Position
  81. GRB 050126: Radio Observations
  82. GRB050128 Swift-BAT observations
  83. GRB 050128: Swift XRT prompt afterglow position
  84. GRB 050124: K-band afterglow observations
  85. GRB050126: MASTER optical limit for KECK OT
  86. GRB050126: Burst Parameters Measured by BAT
  87. GRB050126: MASTER optical observations
  88. GRB 050126: Prompt XRT detection and localization
  89. GRB050124: No Swift UVOT Detection of Afterglow Emission
  90. GRB 050117a: Radio Observations
  91. GRB050124,optical observation
  92. GRB050124: Updated Swift XRT Position and Fluxes
  93. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  94. GRB050124: Refined BAT position, spectral and fluence information
  95. GRB050124: Swift-BAT position of a double-peaked burst
  96. GRB050117a: Radio Observations
  97. GRB050117a: Refined analysis
  98. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  99. GRB050117b: Swift-BAT detection of a weak burst
  100. GRB050117: optical observation

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