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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"

26357 results found.

  1. GRB050319: VLA Observations
  2. GRB050319: radio observation
  3. GRB 050319: Swift-UVOT detection of the afterglow
  4. GRB 050315: Variability Analysis of Swift BAT Time History
  5. GRB050319: Radio Observations
  6. GRB 050319: NIR afterglow candidate
  7. GRB 050319:Near IR afterglow
  8. GRB 050318: SWIFT-UVOT refined analysis
  9. GRB 050319 : Confirmation of optical afterglow decay
  10. GRB 050319: Swift-BAT refined analysis
  11. GRB050319,optical observation
  12. GRB 050318: Swift/UVOT detection of afterglow emission
  13. RXTE Observations of GRB050318
  14. GRB050223: analysis of the XMM-Newton observation
  15. GRB050316: MASTER before, simultanious and follow up optical
  16. GRB 050306: ROTSE-III early limits
  17. GRB050316: MASTER optical observations
  18. GRB 050315: Swift-BAT further refined analysis
  19. GRB 050315 I-band observations
  20. GRB050315: Radio afterglow
  21. GRB050315: Swift-BAT Refined analysis
  22. Non-detection of GRB050315 in ATCA Radio Observations
  23. GRB 050219b: Gemini/GNIRS near-infrared spectroscopy
  24. GRB 050315: Early Observations with Swift/UVOT
  25. GRB 050306: Radio Observations
  26. GRB050306: 250 GHz upper limit with MAMBO at the IRAM 30m
  27. GRB 050306: optical afterglow
  28. Swift-BAT trigger 107873: No Swift XRT counterpart
  29. GRB 050306: Confirmation of X-ray afterglow
  30. GRB 050306: further TAROT optical data
  31. GRB050309: Early optical limit from P60
  32. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  33. GRB 050309 : Lulin R-band observation
  34. Swift 107873: P60 Optical Observations
  35. GRB 050306: R-band observations
  36. GRB 050306: REM optical-infrared observations
  37. GRB 050306: Possible X-ray Afterglow Position from the Swift
  38. GRB 050306: TAROT optical observations
  39. GRB 050306,optical observation
  40. Ongoing activity of SGR 1806-20 after the giant flare
  41. GRB050215B: Late-Time Swift UVOT Observations
  42. PROMPT VRcIc Observations of GRB 050223
  43. XRF/GRB 050215B: Radio Observations
  44. XMM-Newton Images of GRB 050223
  45. GRB 050219b: candidate NIR afterglow
  46. Confirmed XRF nature for GRB050215b
  47. GRB050223 XMM-Newton observation
  48. INTEGRAL detection of GRB 050223
  49. GRB050223: ROTSE-III Optical Observations
  50. GRB 050223 Swift/BAT detection of a burst
  51. GRB 050223: Swift XRT Position
  52. HETE-2 Observations of GRB 050215b (=U11570): A Likely X-Ray Flash
  53. GRB050215b: Faulkes North and SDSS limits on UKIRT candidate
  54. GRB 050219a: Optical observations from LCO
  55. GRB 050219b: Optical and near-IR observations from LCO
  56. GRB 050219b: Swift-BAT detection of a burst
  57. GRB 050219b: CORRECTION: Swift XRT Position
  58. GRB 050219b: Swift XRT Position
  59. GRB 050219: Swift-BAT detection of a burst
  60. GRB 050215b: XRT confirmation of IR afterglow candidate
  61. GRB050215b: P60 Optical Observations
  62. GRB 050215b: Swift XRT Source Variability
  63. GRB 050215B: candidate afterglow
  64. GRB 050215b : Lulin follow-up observation
  65. GRB 050215b, BOOTES-2 simultaneous optical observations
  66. GRB050215A: ROTSE-III Optical Observations
  67. GRB050209: TAROT optical observations
  68. GRB 050209(=U11568): Duration and spectrum
  69. GRB050209: REM optical observations
  70. GRB 050209 I-band observation
  71. GRB 050209 Optical observations
  72. GRB050209: P60 Optical Observations
  73. GRB 050128: Radio observations
  74. Further analysis of the short Swift-BAT GRB 050202
  75. GRB 050202: Short burst detected by Swift-BAT
  76. GRB 050128 Optical observation with REM
  77. SGR1806-20: Swift-BAT detection of a large normal burst
  78. GRB 050128: near-infrared observations with REM
  79. GRB050128,optical observations
  80. GRB050128 Swift-BAT observations
  81. GRB 050128: Swift XRT prompt afterglow position
  82. GRB050126: MASTER optical limit for KECK OT
  83. GRB050126: Burst Parameters Measured by BAT
  84. GRB050126: MASTER optical observations
  85. GRB 050124 I-band observation
  86. GRB050124,optical observation
  87. GRB 050124 : Lulin R-band follow-up observation
  88. GRB050124: Updated Swift XRT Position and Fluxes
  89. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  90. GRB050124: Refined BAT position, spectral and fluence information
  91. GRB 050123 : I-band follow-up observation
  92. GRB050123,optical observation
  93. GRB 050123: KAIT observations
  94. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  95. GRB050117: Refined XRT position
  96. GRB050117: MASTER optical observations
  97. MASTER:GRB050117 SWIFT
  98. GRB050117: Swift XRT Position
  99. Triangulation of Short Hard GRB050112 (large error box)
  100. SGR 1806-20: Further VLA Observations

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