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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"

24610 results found.

  1. GRB 011121 J-Band Astrometry
  2. GRB 011121: Detection of Bright IR Counterpart
  3. GRB011121: possible redshift, continued decay
  4. GRB 011030: TNG K-band observation
  5. XRF011030: J and K band observations
  6. XRF011030: Chandra Observations
  7. GRB011030: Z-band observations
  8. GRB 011030 R band observations
  9. GRB 011030 I-band Observation
  10. The X-ray Flash 011030 ('GRB 011030')
  11. Non-triggered burst 011030 ("GRB 011030")
  12. The Radio Afterglow from the X-ray Rich GRB 011030
  13. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  14. GRB 970828: HST Observations of the Host Galaxy
  15. GRB 000131: HST Detection of the Host Galaxy
  16. GRB 970828: HST Observations of the Host Galaxy
  17. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  18. GRB011019: Subaru Optical Observations
  19. GRB 011030 I-band Observations
  20. GRB 011030 K-band Observations
  21. GRB010921, optical observations
  22. GRB011030 - further refinement WFC position
  23. GRB 011030, Radio observations
  24. GRB011030: radio search
  25. GRB 010921: Possible supernova component
  26. GRB010921, optical observation at early time
  27. GRB 010921, I-band observations
  28. GRB011019, optical observations
  29. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  30. GRB 010921: The afterglow of HETE #1761
  31. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  32. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  33. GRB010923 as seen by BeppoSAX GRBM
  34. GRB010928(=H1770): Localization of a Long GRB by HETE
  35. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  36. GRB010921, negative optical observations
  37. GRB010921 field photometry
  38. H1761: A Bright GRB Detected by HETE
  39. GRB000926, Host Galaxy Observations
  40. GRB001109, Host Galaxy Spectroscopic Observations
  41. Probable SGR or Short Duration GRB Detected by HETE
  42. GCN and HETE status
  43. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  44. GRB 010222 - WHT BVRI images
  45. SGR1900+14 burst seen by HETE: BeppoSAX data
  46. GRB 010629 Optical Observations
  47. SGR1900+14: High Fluence Burst Localized by HETE
  48. GRB010629, optical observations
  49. GRB010629: A Burst Localized by HETE
  50. SGR1900+14: Second Burst Localized by HETE
  51. SGR1900+14: A Burst Localized by HETE
  52. SGR1806-20: A Second, Intense Burst Localized by HETE
  53. SGR1806-20: Localization by HETE
  54. HETE Fully-Automated GCN Notices
  55. GRB000301C: Late-time HST/STIS observation
  56. GRB010518: a faint BeppoSAX detection
  57. GRB000418: HST/STIS Second-epoch Observations
  58. X-ray precursors to the large flare from SGR 1900+14
  59. GRB010427, Gamma Ray Observations
  60. SGR 1900+14: No evidence of extended X-ray emission
  61. SGR 1900+14 : RXTE observations
  62. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  63. SGR 1900+14: Correction to GCN 1049
  64. GRB 010222 /corrections to VBT data
  65. Millimeter observation of SGR 1900+14
  66. SGR 1900+14: Detection of extended X-ray emission
  67. SGR 1900+14, Chandra observations
  68. SGR1900+14, I-band observations
  69. GRB010412, field photometry
  70. Giant flare from SGR1900+14
  71. GRB 010326b Optical Observations
  72. GRB010412: BeppoSAX GRBM and WFC observations
  73. GRB010324, revised field photometry
  74. REVISED LOCATION OF GRB010326A
  75. GRB 980326: Late-time HST/STIS observations
  76. GRB010324, field photometry
  77. GRB010326B, field photometry
  78. GRB010326, field photometry
  79. GRB010220, field photometry
  80. Further Optical Observations of GRB 010324
  81. GRB010222, CXO X-ray observations
  82. GRB010324, optical observations
  83. GRB010326B: Localization by HETE (2nd GRB for this date)
  84. GRB 010326 optical observations
  85. GRB010326: Refined Localization by HETE
  86. GRB010326: Localization by HETE
  87. Optical Observations of GRB 010324
  88. GRB010222, late-time optical observation
  89. Support extension to the BeppoSAX mission
  90. GRB 010222 - HEGRA GeV/TeV Observations
  91. GRB010222: Chandra X-ray Observatory Observation
  92. GRB010222: Sub-millimeter vanishing act
  93. GRB010222 - Optical observation
  94. GRB 010222, Optical Observations
  95. GRB010222 - Optical observation
  96. GRB 010222: High-Resolution Keck Spectroscopy
  97. GRB 010214, I-band data
  98. GRB 010222
  99. GRB010222 further R-band photometry
  100. GRB010222: R-band data

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