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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').
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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"

20360 results found.

  1. Fading of the optical source associated of XRF 011211
  2. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  3. GRB011130 (XRF011130) Chandra Observations
  4. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  5. GRB 011130: Magellan spectroscopy
  6. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  7. GRB 011130, K band observations
  8. GRB011130, optical observations
  9. GRB011130 (XRF011130) SDSS PT i-band observations
  10. XRF011130: Infrared Observations
  11. GRB011130 (=XRF011130): Revised Localization of an X-ray
  12. GRB 011121
  13. GRB 011121: J-band observations
  14. GRB 011121: NIR observations, host galaxy?
  15. GRB010921 - Milagro GeV/TeV Observations
  16. GRB 011121: HST Scheduled
  17. GRB011121: UBRI Observations
  18. GRB011121
  19. GRB 011121 J-Band Astrometry
  20. GRB 011121: Detection of Bright IR Counterpart
  21. GRB011121: possible redshift, continued decay
  22. GRB 011030: TNG K-band observation
  23. XRF011030: J and K band observations
  24. XRF011030: Chandra Observations
  25. GRB011030: Z-band observations
  26. The X-ray Flash 011030 ('GRB 011030')
  27. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  28. GRB 970828: HST Observations of the Host Galaxy
  29. GRB 000131: HST Detection of the Host Galaxy
  30. GRB 970828: HST Observations of the Host Galaxy
  31. GRB011019: Subaru Optical Observations
  32. GRB011030 - further refinement WFC position
  33. GRB011030: radio search
  34. GRB 010921: Possible supernova component
  35. GRB010921, optical observation at early time
  36. GRB 010921, I-band observations
  37. GRB011019, optical observations
  38. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  39. GRB010921: Spectroscopy of the Host Galaxy
  40. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  41. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  42. GRB010923 as seen by BeppoSAX GRBM
  43. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  44. GRB010921, negative optical observations
  45. GRB010921 field photometry
  46. GRB010921 Optical Observations
  47. HETE Trigger #1760 (GRB 010920B?): a new optical source
  48. GRB000926, Host Galaxy Observations
  49. GRB001109, Host Galaxy Spectroscopic Observations
  50. GRB 010222: HST observations -- host galaxy and late-time decay
  51. BeppoSAX/GRBM detection of GRB 010801
  52. GCN and HETE status
  53. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  54. GRB 010222 - WHT BVRI images
  55. GRB 010629 Optical Observations
  56. GRB010629: Optical Observations
  57. SGR1900+14: High Fluence Burst Localized by HETE
  58. GRB010629, optical observations
  59. GRB010629: A Burst Localized by HETE
  60. SGR1900+14: Second Burst Localized by HETE
  61. SGR1900+14: A Burst Localized by HETE
  62. SGR1806-20: A Second, Intense Burst Localized by HETE
  63. SGR1806-20: Localization by HETE
  64. IPN triangulation of GRB010613
  65. HETE Fully-Automated GCN Notices
  66. GRB000301C: Late-time HST/STIS observation
  67. GRB010518: a faint BeppoSAX detection
  68. GRB000418: HST/STIS Second-epoch Observations
  69. X-ray precursors to the large flare from SGR 1900+14
  70. SGR 1900+14 : RXTE observations
  71. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  72. Millimeter observation of SGR 1900+14
  73. SGR 1900+14, Chandra observations
  74. Chandra Observations of SGR 1900+14
  75. SGR1900+14, I-band observations
  76. IPN Triangulation of the Giant Flare from SGR1900+14
  77. GRB010412, field photometry
  78. Giant flare from SGR1900+14
  79. GRB 010326b Optical Observations
  80. GRB010412: BeppoSAX GRBM and WFC observations
  81. GRB010324, revised field photometry
  82. GRB 980326: Late-time HST/STIS observations
  83. GRB010324, field photometry
  84. GRB010326B, field photometry
  85. GRB010326, field photometry
  86. GRB010220, field photometry
  87. Further Optical Observations of GRB 010324
  88. GRB010222, CXO X-ray 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. Optical Observations of GRB 010324
  95. GRB010222, late-time optical observation
  96. Support extension to the BeppoSAX mission
  97. GRB 010222 - HEGRA GeV/TeV Observations
  98. GRB010222 - Optical observation
  99. GRB 010222, Optical Observations
  100. GRB 010214, I-band data

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