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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"

24705 results found.

  1. XRF011030: Chandra Observations
  2. GRB011030: Z-band observations
  3. GRB 011030 R band observations
  4. GRB 011030 I-band Observation
  5. The X-ray Flash 011030 ('GRB 011030')
  6. Non-triggered burst 011030 ("GRB 011030")
  7. The Radio Afterglow from the X-ray Rich GRB 011030
  8. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  9. GRB 970828: HST Observations of the Host Galaxy
  10. GRB 000131: HST Detection of the Host Galaxy
  11. GRB 970828: HST Observations of the Host Galaxy
  12. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  13. GRB011019: Subaru Optical Observations
  14. GRB 011030 I-band Observations
  15. GRB 011030 K-band Observations
  16. GRB010921, optical observations
  17. GRB011030 - further refinement WFC position
  18. GRB 011030, Radio observations
  19. GRB011030: radio search
  20. GRB 010921: Possible supernova component
  21. GRB010921, optical observation at early time
  22. GRB 010921, I-band observations
  23. GRB011019, optical observations
  24. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  25. GRB 010921: The afterglow of HETE #1761
  26. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  27. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  28. GRB010923 as seen by BeppoSAX GRBM
  29. GRB010928(=H1770): Localization of a Long GRB by HETE
  30. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  31. GRB010921, negative optical observations
  32. GRB010921 field photometry
  33. H1761: A Bright GRB Detected by HETE
  34. GRB000926, Host Galaxy Observations
  35. GRB001109, Host Galaxy Spectroscopic Observations
  36. Probable SGR or Short Duration GRB Detected by HETE
  37. GCN and HETE status
  38. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  39. GRB 010222 - WHT BVRI images
  40. SGR1900+14 burst seen by HETE: BeppoSAX data
  41. GRB 010629 Optical Observations
  42. SGR1900+14: High Fluence Burst Localized by HETE
  43. GRB010629, optical observations
  44. GRB010629: A Burst Localized by HETE
  45. SGR1900+14: Second Burst Localized by HETE
  46. SGR1900+14: A Burst Localized by HETE
  47. SGR1806-20: A Second, Intense Burst Localized by HETE
  48. SGR1806-20: Localization by HETE
  49. HETE Fully-Automated GCN Notices
  50. GRB000301C: Late-time HST/STIS observation
  51. GRB010518: a faint BeppoSAX detection
  52. GRB000418: HST/STIS Second-epoch Observations
  53. X-ray precursors to the large flare from SGR 1900+14
  54. GRB010427, Gamma Ray Observations
  55. SGR 1900+14: No evidence of extended X-ray emission
  56. SGR 1900+14 : RXTE observations
  57. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  58. SGR 1900+14: Correction to GCN 1049
  59. GRB 010222 /corrections to VBT data
  60. Millimeter observation of SGR 1900+14
  61. SGR 1900+14: Detection of extended X-ray emission
  62. SGR 1900+14, Chandra observations
  63. SGR1900+14, I-band observations
  64. GRB010412, field photometry
  65. Giant flare from SGR1900+14
  66. GRB 010326b Optical Observations
  67. GRB010412: BeppoSAX GRBM and WFC observations
  68. GRB010324, revised field photometry
  69. REVISED LOCATION OF GRB010326A
  70. GRB 980326: Late-time HST/STIS observations
  71. GRB010324, field photometry
  72. GRB010326B, field photometry
  73. GRB010326, field photometry
  74. GRB010220, field photometry
  75. Further Optical Observations of GRB 010324
  76. GRB010222, CXO X-ray observations
  77. GRB010324, optical observations
  78. GRB010326B: Localization by HETE (2nd GRB for this date)
  79. GRB 010326 optical observations
  80. GRB010326: Refined Localization by HETE
  81. GRB010326: Localization by HETE
  82. Optical Observations of GRB 010324
  83. GRB010222, late-time optical observation
  84. Support extension to the BeppoSAX mission
  85. GRB 010222 - HEGRA GeV/TeV Observations
  86. GRB010222: Chandra X-ray Observatory Observation
  87. GRB010222: Sub-millimeter vanishing act
  88. GRB010222 - Optical observation
  89. GRB 010222, Optical Observations
  90. GRB010222 - Optical observation
  91. GRB 010222: High-Resolution Keck Spectroscopy
  92. GRB 010214, I-band data
  93. GRB 010222
  94. GRB010222 further R-band photometry
  95. GRB010222: R-band data
  96. GRB 010222: Keck Spectroscopy
  97. GRB010214, field photometry
  98. GRB010222, field photometry
  99. GRB010222 further R-band photometry
  100. GRB010222, possible increase of optical decay slope

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