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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"

42193 results found.

  1. GRB 011030, WSRT radio observations
  2. GRB011030 - further refinement WFC position
  3. GRB 011030, Radio observations
  4. GRB 011030, R-band observations
  5. BeppoSAX ALERT: Possible X-ray rich GRB011030
  6. GRB 010921: Possible supernova component
  7. GRB011019: NEAT Optical Observations
  8. GRB011019: ROTSE-III optical observations
  9. GRB010921, optical observation at early time
  10. GRB011019: Optical observations
  11. GRB011019, optical observations -- correction
  12. GRB011019, optical observations
  13. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  14. GRB010921: Spectroscopy of the Host Galaxy
  15. GRB 010921: The afterglow of HETE #1761
  16. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  17. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  18. GRB010923 as seen by BeppoSAX GRBM
  19. GRB010928(=H1770): Localization of a Long GRB by HETE
  20. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  21. GRB010921, negative optical observations
  22. GRB010921 field photometry
  23. GRB010921 Optical Observations
  24. GRB 010921 DPOSS Images Available
  25. IPN triangulation of GRB010921 (=H1761)
  26. H1761: A Bright GRB Detected by HETE
  27. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  28. HETE Trigger #1760 (GRB 010920B?): a new optical source
  29. HETE Trigger #1759 (GRB 010920?) optical observations
  30. GRB000926, Host Galaxy Observations
  31. GRB001109, Host Galaxy Spectroscopic Observations
  32. Probable SGR or Short Duration GRB Detected by HETE
  33. GRB000926 Host Galaxy Observations
  34. GRB 010222: HST observations -- host galaxy and late-time decay
  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. GRB010629: Optical Observations
  41. SGR1900+14: High Fluence Burst Localized by HETE
  42. GRB010629, optical observations
  43. IPN triangulation of GRB010629
  44. GRB010629: A Burst Localized by HETE
  45. SGR1900+14: Second Burst Localized by HETE
  46. SGR1900+14: A Burst Localized by HETE
  47. Possible burst from SGR1806-20
  48. IPN detection of SGR1900+14
  49. SGR1806-20: A Second, Intense Burst Localized by HETE
  50. GRB 00630: Host Galaxy
  51. SGR1806-20: Localization by HETE
  52. IPN triangulation of GRB010613
  53. IPN triangulation of GRB010612
  54. IPN triangulation of GRB010612
  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. GRB010214, optical 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. SGR1900+14
  64. Millimeter observation of SGR 1900+14
  65. SGR 1900+14: Detection of extended X-ray emission
  66. Chandra Observations of SGR 1900+14
  67. SGR 1900+14, Chandra observations
  68. Chandra Observations of SGR 1900+14
  69. SGR1900+14, I-band observations
  70. GRB010412, field photometry
  71. Giant flare from SGR1900+14
  72. GRB 010326b Optical Observations
  73. GRB010412: Optical observations
  74. GRB010412: Optical observations
  75. GRB010412: BeppoSAX GRBM and WFC observations
  76. IPN Triangulation of GRB010412
  77. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  78. GRB Observation Report
  79. GRB010324, revised field photometry
  80. REVISED LOCATION OF GRB010326A
  81. GRB 980326: Late-time HST/STIS observations
  82. GRB010324, field photometry
  83. GRB010326B, field photometry
  84. GRB010326, field photometry
  85. GRB010220, field photometry
  86. Further Optical Observations of GRB 010324
  87. GRB010222, CXO X-ray observations
  88. GRB 010326A: Further optical observations
  89. GRB010324: BeppoSAX/GRBM data
  90. GRB 010326B: Optical observations
  91. GRB010324, optical observations
  92. GRB010326B: Localization by HETE (2nd GRB for this date)
  93. GRB 010326: Optical observations
  94. GRB 010326 optical observations
  95. GRB010326: Refined Localization by HETE
  96. GRB010326: Localization by HETE
  97. Duration, ECT, peak flux and fluence of GRB010324
  98. Optical Observations of GRB 010324
  99. GRB990705, VLT-FORS1 observations of the host galaxy
  100. GRB010222, late-time optical observation

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