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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"

32533 results found.

  1. GRB 011121: Radio Observations
  2. GRB 011121 J-Band Astrometry
  3. GRB011121: continued decay
  4. GRB 011121: Detection of Bright IR Counterpart
  5. GRB011121: possible redshift, continued decay
  6. GRB011121: fading behavior
  7. GRB011121: possible optical counterpart
  8. IPN triangulation of GRB011121
  9. GRB 011030: TNG K-band observation
  10. XRF011030: J and K band observations
  11. XRF011030: Chandra Observations
  12. GRB 011030: K-band observations
  13. GRB011030: Z-band observations
  14. GRB 011030 I-band Observation
  15. The X-ray Flash 011030 ('GRB 011030')
  16. The Radio Afterglow from the X-ray Rich GRB 011030
  17. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  18. GRB 000131: HST Detection of the Host Galaxy
  19. GRB 011019 optical observation
  20. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  21. GRB011019: Subaru Optical Observations
  22. GRB 011030 I-band Observations
  23. GRB 011030 K-band Observations
  24. GRB010921, optical observations
  25. GRB 011030, WSRT radio observations
  26. GRB011030 - further refinement WFC position
  27. GRB 011030, Radio observations
  28. GRB011030: radio search
  29. GRB 011030, R-band observations
  30. BeppoSAX ALERT: Possible X-ray rich GRB011030
  31. GRB 010921: Possible supernova component
  32. GRB011019: ROTSE-III optical observations
  33. GRB 010921, I-band observations
  34. GRB011019: Optical observations
  35. GRB011019, optical observations -- correction
  36. GRB011019, optical observations
  37. GRB010921: Spectroscopy of the Host Galaxy
  38. GRB 010921: The afterglow of HETE #1761
  39. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  40. GRB010923 as seen by BeppoSAX GRBM
  41. GRB010928(=H1770): Localization of a Long GRB by HETE
  42. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  43. GRB010921, negative optical observations
  44. GRB010921 field photometry
  45. GRB 010921 DPOSS Images Available
  46. IPN triangulation of GRB010921 (=H1761)
  47. H1761: A Bright GRB Detected by HETE
  48. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  49. GRB001109, Host Galaxy Astrometry
  50. GRB000926, Host Galaxy Observations
  51. GRB001109, Host Galaxy Spectroscopic Observations
  52. Probable SGR or Short Duration GRB Detected by HETE
  53. GCN and HETE status
  54. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  55. GRB 010222 - WHT BVRI images
  56. SGR1900+14 burst seen by HETE: BeppoSAX data
  57. GRB 010629 Optical Observations
  58. GRB010629: Optical Observations
  59. SGR1900+14: High Fluence Burst Localized by HETE
  60. GRB010629, optical observations
  61. IPN triangulation of GRB010629
  62. SGR1900+14: Second Burst Localized by HETE
  63. SGR1900+14: A Burst Localized by HETE
  64. Possible burst from SGR1806-20
  65. SGR1806-20: A Second, Intense Burst Localized by HETE
  66. IPN triangulation of GRB010613
  67. IPN triangulation of GRB010612
  68. IPN triangulation of GRB010612
  69. HETE Fully-Automated GCN Notices
  70. GRB000301C: Late-time HST/STIS observation
  71. GRB000418: HST/STIS Second-epoch Observations
  72. X-ray precursors to the large flare from SGR 1900+14
  73. GRB010214, optical observations
  74. SGR 1900+14: No evidence of extended X-ray emission
  75. SGR 1900+14 : RXTE observations
  76. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  77. SGR1900+14 - correction
  78. SGR1900+14
  79. SGR 1900+14: Correction to GCN 1049
  80. Millimeter observation of SGR 1900+14
  81. SGR 1900+14: Detection of extended X-ray emission
  82. Chandra Observations of SGR 1900+14
  83. SGR 1900+14, Chandra observations
  84. Chandra Observations of SGR 1900+14
  85. Possible precursor to the SGR1900+14 giant burst
  86. SGR1900+14, I-band observations
  87. IPN Triangulation of the Giant Flare from SGR1900+14
  88. GRB 010326b Optical Observations
  89. GRB010412: Optical observations
  90. GRB010412: Optical observations
  91. IPN Triangulation of GRB010412
  92. GRB Observation Report
  93. REVISED LOCATION OF GRB010326A
  94. GRB 980326: Late-time HST/STIS observations
  95. GRB010324, field photometry
  96. GRB010326B, field photometry
  97. GRB010326, field photometry
  98. GRB010220, field photometry
  99. Further Optical Observations of GRB 010324
  100. GRB010222, CXO X-ray observations

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