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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"

35991 results found.

  1. The X-ray Flash 011030 ('GRB 011030')
  2. Non-triggered burst 011030 ("GRB 011030")
  3. The Radio Afterglow from the X-ray Rich GRB 011030
  4. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  5. GRB 970828: HST Observations of the Host Galaxy
  6. GRB 000131: HST Detection of the Host Galaxy
  7. GRB 970828: HST Observations of the Host Galaxy
  8. GRB010921, optical observation
  9. GRB 011019 optical observation
  10. GRB011019: Subaru Optical Observations
  11. GRB 011030 I-band Observations
  12. GRB 011030 K-band Observations
  13. GRB010921, optical observations
  14. GRB 011030, WSRT radio observations
  15. GRB011030 - further refinement WFC position
  16. GRB 011030, Radio observations
  17. GRB 011030, R-band observations
  18. BeppoSAX ALERT: Possible X-ray rich GRB011030
  19. GRB 010921: Possible supernova component
  20. GRB011019: NEAT Optical Observations
  21. GRB010921, optical observation at early time
  22. GRB 010921, I-band observations
  23. GRB011019: Optical observations
  24. GRB011019, optical observations
  25. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  26. GRB010921: Spectroscopy of the Host Galaxy
  27. GRB 010921: The afterglow of HETE #1761
  28. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  29. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  30. GRB010923 as seen by BeppoSAX GRBM
  31. GRB010928(=H1770): Localization of a Long GRB by HETE
  32. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  33. GRB010921, negative optical observations
  34. GRB010921 field photometry
  35. GRB010921 Optical Observations
  36. GRB 010921 DPOSS Images Available
  37. IPN triangulation of GRB010921 (=H1761)
  38. H1761: A Bright GRB Detected by HETE
  39. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  40. HETE Trigger #1760 (GRB 010920B?): a new optical source
  41. HETE Trigger #1759 (GRB 010920?) optical observations
  42. GRB001109, Host Galaxy Astrometry
  43. GRB000926, Host Galaxy Observations
  44. GRB001109, Host Galaxy Spectroscopic Observations
  45. Probable SGR or Short Duration GRB Detected by HETE
  46. GRB000926 Host Galaxy Observations
  47. GRB 010222: HST observations -- host galaxy and late-time decay
  48. BeppoSAX/GRBM detection of GRB 010801
  49. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  50. GRB 010222 - WHT BVRI images
  51. GRB 010629 Optical Observations
  52. GRB010629: Optical Observations
  53. GRB010629, optical observations
  54. IPN triangulation of GRB010629
  55. GRB010629: A Burst Localized by HETE
  56. Possible burst from SGR1806-20
  57. IPN detection of SGR1900+14
  58. GRB 00630: Host Galaxy
  59. IPN triangulation of GRB010613
  60. IPN triangulation of GRB010612
  61. HETE Fully-Automated GCN Notices
  62. GRB000301C: Late-time HST/STIS observation
  63. GRB010518: a faint BeppoSAX detection
  64. GRB000418: HST/STIS Second-epoch Observations
  65. GRB010427, Gamma Ray Observations
  66. SGR1900+14
  67. GRB 010222 /corrections to VBT data
  68. Possible precursor to the SGR1900+14 giant burst
  69. IPN Triangulation of the Giant Flare from SGR1900+14
  70. GRB010412, field photometry
  71. GRB 010326b Optical Observations
  72. GRB010412: Optical observations
  73. GRB010412: Optical observations
  74. IPN Triangulation of GRB010412
  75. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  76. BeppoSAX GRB ALERT: 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. GRB 010326A: Further optical observations
  87. GRB010324: BeppoSAX/GRBM data
  88. GRB 010326B: Optical observations
  89. GRB010324, optical observations
  90. GRB010326B: Localization by HETE (2nd GRB for this date)
  91. GRB 010326: Optical observations
  92. GRB 010326 optical observations
  93. GRB010326: Refined Localization by HETE
  94. GRB010326: Localization by HETE
  95. Duration, ECT, peak flux and fluence of GRB010324
  96. Optical Observations of GRB 010324
  97. IPN TRIANGULATION OF GRB010324
  98. GRB990705, VLT-FORS1 observations of the host galaxy
  99. GRB010222, late-time optical observation
  100. Support extension to the BeppoSAX mission

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