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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"

24603 results found.

  1. GRB 011030 R band observations
  2. GRB 011030 I-band Observation
  3. The X-ray Flash 011030 ('GRB 011030')
  4. Non-triggered burst 011030 ("GRB 011030")
  5. The Radio Afterglow from the X-ray Rich GRB 011030
  6. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  7. GRB 970828: HST Observations of the Host Galaxy
  8. GRB 000131: HST Detection of the Host Galaxy
  9. GRB 970828: HST Observations of the Host Galaxy
  10. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  11. GRB011019: Subaru Optical Observations
  12. GRB 011030 I-band Observations
  13. GRB 011030 K-band Observations
  14. GRB010921, optical observations
  15. GRB011030 - further refinement WFC position
  16. GRB 011030, Radio observations
  17. GRB011030: radio search
  18. GRB 010921: Possible supernova component
  19. GRB010921, optical observation at early time
  20. GRB 010921, I-band observations
  21. GRB011019, optical observations
  22. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  23. GRB 010921: The afterglow of HETE #1761
  24. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  25. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  26. GRB010923 as seen by BeppoSAX GRBM
  27. GRB010928(=H1770): Localization of a Long GRB by HETE
  28. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  29. GRB010921, negative optical observations
  30. GRB010921 field photometry
  31. H1761: A Bright GRB Detected by HETE
  32. GRB000926, Host Galaxy Observations
  33. GRB001109, Host Galaxy Spectroscopic Observations
  34. Probable SGR or Short Duration GRB Detected by HETE
  35. GCN and HETE status
  36. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  37. GRB 010222 - WHT BVRI images
  38. SGR1900+14 burst seen by HETE: BeppoSAX data
  39. GRB 010629 Optical Observations
  40. SGR1900+14: High Fluence Burst Localized by HETE
  41. GRB010629, optical observations
  42. GRB010629: A Burst Localized by HETE
  43. SGR1900+14: Second Burst Localized by HETE
  44. SGR1900+14: A Burst Localized by HETE
  45. SGR1806-20: A Second, Intense Burst Localized by HETE
  46. SGR1806-20: Localization by HETE
  47. HETE Fully-Automated GCN Notices
  48. GRB000301C: Late-time HST/STIS observation
  49. GRB010518: a faint BeppoSAX detection
  50. GRB000418: HST/STIS Second-epoch Observations
  51. X-ray precursors to the large flare from SGR 1900+14
  52. GRB010427, Gamma Ray Observations
  53. SGR 1900+14: No evidence of extended X-ray emission
  54. SGR 1900+14 : RXTE observations
  55. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  56. SGR 1900+14: Correction to GCN 1049
  57. GRB 010222 /corrections to VBT data
  58. Millimeter observation of SGR 1900+14
  59. SGR 1900+14: Detection of extended X-ray emission
  60. SGR 1900+14, Chandra observations
  61. SGR1900+14, I-band observations
  62. GRB010412, field photometry
  63. Giant flare from SGR1900+14
  64. GRB 010326b Optical Observations
  65. GRB010412: BeppoSAX GRBM and WFC observations
  66. GRB010324, revised field photometry
  67. REVISED LOCATION OF GRB010326A
  68. GRB 980326: Late-time HST/STIS observations
  69. GRB010324, field photometry
  70. GRB010326B, field photometry
  71. GRB010326, field photometry
  72. GRB010220, field photometry
  73. Further Optical Observations of GRB 010324
  74. GRB010222, CXO X-ray observations
  75. GRB010324, optical observations
  76. GRB010326B: Localization by HETE (2nd GRB for this date)
  77. GRB 010326 optical observations
  78. GRB010326: Refined Localization by HETE
  79. GRB010326: Localization by HETE
  80. Optical Observations of GRB 010324
  81. GRB010222, late-time optical observation
  82. Support extension to the BeppoSAX mission
  83. GRB 010222 - HEGRA GeV/TeV Observations
  84. GRB010222: Chandra X-ray Observatory Observation
  85. GRB010222: Sub-millimeter vanishing act
  86. GRB010222 - Optical observation
  87. GRB 010222, Optical Observations
  88. GRB010222 - Optical observation
  89. GRB 010222: High-Resolution Keck Spectroscopy
  90. GRB 010214, I-band data
  91. GRB 010222
  92. GRB010222 further R-band photometry
  93. GRB010222: R-band data
  94. GRB 010222: Keck Spectroscopy
  95. GRB010214, field photometry
  96. GRB010222, field photometry
  97. GRB010222 further R-band photometry
  98. GRB010222, possible increase of optical decay slope
  99. GRB 010222 Kyoto optical observation
  100. GRB010222 R-BAND OBSERVATION

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