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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"

20815 results found.

  1. GRB 011130, K band observations
  2. GRB011130, optical observations
  3. GRB011130 (XRF011130) SDSS PT i-band observations
  4. XRF011130: Infrared Observations
  5. GRB011130 (=XRF011130), Optical Observations
  6. GRB 011121
  7. GRB 011121: J-band observations
  8. GRB 011121: NIR observations, host galaxy?
  9. GRB011121: UBRI Observations
  10. GRB 011121: Radio Observations
  11. GRB 011121 J-Band Astrometry
  12. GRB 011121: Detection of Bright IR Counterpart
  13. GRB011121: possible redshift, continued decay
  14. IPN triangulation of GRB011121
  15. GRB 011030: TNG K-band observation
  16. XRF011030: J and K band observations
  17. XRF011030: Chandra Observations
  18. GRB011030: Z-band observations
  19. The X-ray Flash 011030 ('GRB 011030')
  20. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  21. GRB 970828: HST Observations of the Host Galaxy
  22. GRB 000131: HST Detection of the Host Galaxy
  23. GRB 970828: HST Observations of the Host Galaxy
  24. GRB011019: Subaru Optical Observations
  25. GRB011030 - further refinement WFC position
  26. GRB 011030, Radio observations
  27. GRB011030: radio search
  28. X-ray rich GRB011030: BeppoSAX refined positions
  29. GRB 010921: Possible supernova component
  30. GRB010921, optical observation at early time
  31. GRB 010921, I-band observations
  32. GRB011019, optical observations
  33. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  34. GRB 010921: The afterglow of HETE #1761
  35. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  36. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  37. GRB010928(=H1770): Localization of a Long GRB by HETE
  38. GRB010921, negative optical observations
  39. GRB010921 field photometry
  40. GRB010921 Optical Observations
  41. IPN triangulation of GRB010921 (=H1761)
  42. H1761: A Bright GRB Detected by HETE
  43. HETE Trigger #1760 (GRB 010920B?): a new optical source
  44. HETE Trigger #1759 (GRB 010920?) optical observations
  45. GRB000926, Host Galaxy Observations
  46. GRB001109, Host Galaxy Spectroscopic Observations
  47. GCN and HETE status
  48. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  49. GRB 010222 - WHT BVRI images
  50. GRB 010629 Optical Observations
  51. GRB010629: Optical Observations
  52. SGR1900+14: High Fluence Burst Localized by HETE
  53. GRB010629, optical observations
  54. IPN triangulation of GRB010629
  55. GRB010629: A Burst Localized by HETE
  56. SGR1900+14: Second Burst Localized by HETE
  57. SGR1900+14: A Burst Localized by HETE
  58. SGR1806-20: A Second, Intense Burst Localized by HETE
  59. SGR1806-20: Localization by HETE
  60. IPN triangulation of GRB010613
  61. IPN triangulation of GRB010612
  62. HETE Fully-Automated GCN Notices
  63. GRB000301C: Late-time HST/STIS observation
  64. GRB010518: a faint BeppoSAX detection
  65. GRB000418: HST/STIS Second-epoch Observations
  66. X-ray precursors to the large flare from SGR 1900+14
  67. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  68. Millimeter observation of SGR 1900+14
  69. SGR 1900+14: Detection of extended X-ray emission
  70. SGR 1900+14, Chandra observations
  71. SGR1900+14, I-band observations
  72. GRB010412, field photometry
  73. Giant flare from SGR1900+14
  74. GRB 010326b Optical Observations
  75. GRB010412: BeppoSAX GRBM and WFC observations
  76. IPN Triangulation of GRB010412
  77. GRB Observation Report
  78. GRB010324, revised field photometry
  79. REVISED LOCATION OF GRB010326A
  80. GRB 980326: Late-time HST/STIS observations
  81. GRB010324, field photometry
  82. GRB010326B, field photometry
  83. GRB010326, field photometry
  84. GRB010220, field photometry
  85. Further Optical Observations of GRB 010324
  86. GRB010222, CXO X-ray observations
  87. GRB010324, optical observations
  88. GRB010326B: Localization by HETE (2nd GRB for this date)
  89. GRB 010326 optical observations
  90. GRB010326: Refined Localization by HETE
  91. GRB010326: Localization by HETE
  92. Optical Observations of GRB 010324
  93. GRB990705, VLT-FORS1 observations of the host galaxy
  94. GRB010222, late-time optical observation
  95. Support extension to the BeppoSAX mission
  96. GRB 010222, Optical Observations
  97. GRB010220 optical obsercations
  98. GRB 010222: High-Resolution Keck Spectroscopy
  99. GRB 010214, I-band data
  100. GRB 010222

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