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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

23154 results found.

  1. GRB011130, optical observations
  2. GRB011130, optical observations
  3. GRB011130 (=XRF011130): Second Revised Localization by HETE
  4. GRB011130 (XRF011130) optical observations
  5. GRB011130 (XRF011130) SDSS PT i-band observations
  6. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  7. GRB011130 (=XRF011130), Optical Observations
  8. XRF011130: NEAT Optical Observations
  9. GRB011130 (=XRF011130): Revised Localization of an X-ray
  10. GRB 011121
  11. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  12. GRB 011121: J-band observations
  13. GRB011121: UBRI Observations
  14. GRB011121
  15. GRB 011121: Radio Observations
  16. GRB011121: possible redshift, continued decay
  17. GRB011121: fading behavior
  18. GRB011121: possible optical counterpart
  19. IPN triangulation of GRB011121
  20. GRB 011030: TNG K-band observation
  21. GRB011030, optical observation
  22. GRB 011030: K-band observations
  23. GRB011030: Z-band observations
  24. Non-triggered burst 011030 ("GRB 011030")
  25. GRB010921, optical observation
  26. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  27. GRB011019: Subaru Optical Observations
  28. GRB010921, optical observations
  29. GRB011030: radio search
  30. GRB 011030, R-band observations
  31. GRB011019: NEAT Optical Observations
  32. GRB011019: ROTSE-III optical observations
  33. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  34. GRB010921: Spectroscopy of the Host Galaxy
  35. GRB 010921: The afterglow of HETE #1761
  36. GRB010923 as seen by BeppoSAX GRBM
  37. GRB010928(=H1770): Localization of a Long GRB by HETE
  38. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  39. GRB010921 field photometry
  40. GRB010921 Optical Observations
  41. IPN triangulation of GRB010921 (=H1761)
  42. H1761: A Bright GRB Detected by HETE
  43. GRB000926, Host Galaxy Observations
  44. GRB001109, Host Galaxy Spectroscopic Observations
  45. Probable SGR or Short Duration GRB Detected by HETE
  46. GRB000926 Host Galaxy Observations
  47. GRB 010222: HST observations -- host galaxy and late-time decay
  48. BeppoSAX/GRBM detection of GRB 010801
  49. GCN and HETE status
  50. BeppoSAX/GRBM detection of GRB010728
  51. GRB 010222 - WHT BVRI images
  52. SGR1900+14 burst seen by HETE: BeppoSAX data
  53. GRB 010629 Optical Observations
  54. SGR1900+14: High Fluence Burst Localized by HETE
  55. IPN triangulation of GRB010629
  56. GRB010629: A Burst Localized by HETE
  57. SGR1900+14: Second Burst Localized by HETE
  58. SGR1900+14: A Burst Localized by HETE
  59. Possible burst from SGR1806-20
  60. IPN detection of SGR1900+14
  61. SGR1806-20: A Second, Intense Burst Localized by HETE
  62. SGR1806-20: Localization by HETE
  63. GRB000418: HST/STIS Second-epoch Observations
  64. X-ray precursors to the large flare from SGR 1900+14
  65. GRB010427, Gamma Ray Observations
  66. SGR 1900+14 : RXTE observations
  67. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  68. SGR1900+14
  69. GRB 010222 /corrections to VBT data
  70. Millimeter observation of SGR 1900+14
  71. Chandra Observations of SGR 1900+14
  72. Chandra Observations of SGR 1900+14
  73. Possible precursor to the SGR1900+14 giant burst
  74. IPN Triangulation of the Giant Flare from SGR1900+14
  75. GRB010412, field photometry
  76. GRB010412: BeppoSAX GRBM and WFC observations
  77. IPN Triangulation of GRB010412
  78. GRB010412: refined positions from BeppoSAX
  79. GRB Observation Report
  80. REVISED LOCATION OF GRB010326A
  81. GRB 980326: Late-time HST/STIS observations
  82. GRB010324, field photometry
  83. GRB010326B, field photometry
  84. GRB010326, field photometry
  85. GRB010220, field photometry
  86. Further Optical Observations of GRB 010324
  87. GRB010324: BeppoSAX/GRBM data
  88. GRB 010326B: Optical observations
  89. GRB010324, optical observations
  90. GRB010326B: Localization by HETE (2nd GRB for this date)
  91. GRB 010326 optical observations
  92. GRB010326: Refined Localization by HETE
  93. GRB010326: Localization by HETE
  94. Duration, ECT, peak flux and fluence of GRB010324
  95. Optical Observations of GRB 010324
  96. GRB990705, VLT-FORS1 observations of the host galaxy
  97. GRB010222 - Optical observation
  98. GRB010222 - Optical observation
  99. GRB 010222: High-Resolution Keck Spectroscopy
  100. GRB010222: Optical observation and decay

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