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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').

10044 results found.

  1. GRB 050223: Swift XRT Position
  2. HETE-2 Observations of GRB 050215b (=U11570): A Likely X-Ray Flash
  3. GRB050219b: CORRECTION to time of UVOT observations
  4. GRB050215b: Faulkes North and SDSS limits on UKIRT candidate
  5. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  6. GRB 050219b: CORRECTION to refined XRT position
  7. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  8. GRB 050219b: Refined XRT position
  9. GRB 050219b: Swift-BAT detection of a burst
  10. GRB 050219b: CORRECTION: Swift XRT Position
  11. GRB 050219b: Swift XRT Position
  12. GRB 050219a: Refined XRT position
  13. GRB050219a: No Swift UVOT Detection of Afterglow Emission
  14. GRB 050219: Swift-BAT detection of a burst
  15. GRB050215b: Swift UVOT Detection of Afterglow Emission
  16. GRB 050219: Prompt X-ray position
  17. GRB 050215b: XRT confirmation of IR afterglow candidate
  18. GRB 050215b: Swift XRT Source Variability
  19. GRB 050215B: candidate afterglow
  20. GRB 050215B: UKIRT K-band imaging
  21. GRB 050215b: Swift XRT Observations
  22. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  23. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  24. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  25. GRB 050209(=U11568): Duration and spectrum
  26. GRB 050209 I-band observation
  27. GRB050209 (=U11568): A Long GRB Detected by HETE
  28. Further analysis of the short Swift-BAT GRB 050202
  29. GRB 050202: Short burst detected by Swift-BAT
  30. GRB 050128 Optical observation with REM
  31. SGR1806-20: Swift-BAT detection of a large normal burst
  32. GRB050128: Faulkes Telescope South observations
  33. GRB050126: Updated Swift XRT Position
  34. GRB050128 Swift-BAT observations
  35. GRB 050128: Swift XRT prompt afterglow position
  36. GRB050126: Burst Parameters Measured by BAT
  37. GRB 050126: Prompt XRT detection and localization
  38. GRB050124: No Swift UVOT Detection of Afterglow Emission
  39. GRB 050124 I-band observation
  40. GRB050124: Updated Swift XRT Position and Fluxes
  41. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  42. GRB050124: Refined BAT position, spectral and fluence information
  43. GRB050124: Swift-BAT position of a double-peaked burst
  44. GRB 050123 : I-band follow-up observation
  45. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  46. GRB050117a: Refined analysis
  47. GRB050117b: Swift-BAT detection of a weak burst
  48. GRB050117: Refined XRT position
  49. GRB050117: Swift-BAT detection of a long multi-peaked burst
  50. GRB050117: Swift XRT Position
  51. SGR 1806-20: RXTE/PCA pulse frequency during flare
  52. SGR1806-20: Swift-BAT observations of two additional bursts
  53. SGR1806: Detection of a Sudden Ionospheric Disturbance
  54. SGR1806-20: Swift-BAT observation of the 041227 super-flare
  55. GRB041228: Swift-BAT detection of a burst
  56. GRB041226: Swift-BAT detection of a burst
  57. GRB 041223: XRT afterglow spectrum and light curve
  58. GRB 041223 Fluence measured by Swift-BAT
  59. GRB041224: Swift-BAT detection of a soft burst
  60. GRB041223: optical and NIR observations with REM
  61. Swift-BAT Time History of GRB041219
  62. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  63. GRB041223: Swift-BAT detection of a bright long burst
  64. GRB041220: Swift-BAT burst
  65. GRB041219c: Third Burst in One Day from Swift-BAT
  66. GRB041219b: A Swift-BAT burst
  67. Swift-BAT detection of the bright long burst GRB041219
  68. GRB 041218: Optical observations
  69. GRB041217: The First GRB Located On-Board Swift
  70. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  71. GRB970815: Discovery of Optical Afterglow
  72. GRB041006: RTT150 Optical Observations
  73. GRB041006: RTT150 Optical Observations
  74. GRB 041016: Optical limits in V, R, I
  75. GRB041006: Fading X-ray Afterglow Observed with Chandra
  76. GRB041006, optical observation in CrAO
  77. GRB041006: Liverpool Telescope optical observations
  78. GRB 041006: Colour measurement
  79. GRB041006: break in the light curve
  80. GRB041006 (= H3570): Chandra Observations In Progress
  81. GRB 041006: Optical decay
  82. GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
  83. GRB 041006: Finding chart
  84. GRB 041006: Optical afterglow candidate
  85. GRB040924, RTT150 optical observation
  86. GRB 040924: detection of possible host galaxy by Subaru
  87. GRB040924, RTT150 optical observation
  88. GRB 040924: NIR finding chart
  89. GRB 040924: RTT150 optical observations
  90. IPN triangulation of GRB040924 (H3564)
  91. GRB 040924(=H3564): A Short, Bright GRB Localized in Real Time by HETE
  92. GRB040912(=H3557): Chandra Candidate X-ray Afterglow
  93. XRF040916: continuing decay of OT
  94. GRB040912(=H3557): Candidate Optical Afterglow
  95. XRF040916: Optical Transient Candidate by Subaru
  96. XRF 040912 (=H3557): Spectral and Temporal Properties
  97. GRB040912(=H3557): Observations with the Chandra X-ray Observatory
  98. GRB040916: Optical observations
  99. GRB040916 (= H3558): Improved Localization from HETE WXM
  100. GRB040916 (= H3558): A Long XRF Localized by HETE

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