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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"

32820 results found.

  1. GRB011130 (XRF011130) SDSS PT i-band observations
  2. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  3. XRF011130: NEAT Optical Observations
  4. GRB011130 (=XRF011130): Revised Localization of an X-ray
  5. GRB001109, Radio Monitoring
  6. GRB 011121: Errata URL
  7. GRB 011121
  8. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  9. GRB 011121: J-band observations
  10. GRB 011121: NIR observations, host galaxy?
  11. GRB 011121: HST Scheduled
  12. GRB011121: fainter still
  13. Correction: GCN1157 (GRB 011121)
  14. GRB 011121: Radio Observations
  15. GRB 011121 J-Band Astrometry
  16. GRB011121: continued decay
  17. GRB 011121: Detection of Bright IR Counterpart
  18. GRB011121: possible redshift, continued decay
  19. IPN triangulation of GRB011121
  20. BEPPOSAX GRB011121
  21. GRB 011030: TNG K-band observation
  22. XRF011030: Chandra Observations
  23. GRB 011030: K-band observations
  24. GRB 011030 R band observations
  25. GRB 011030 I-band Observation
  26. The X-ray Flash 011030 ('GRB 011030')
  27. Non-triggered burst 011030 ("GRB 011030")
  28. The Radio Afterglow from the X-ray Rich GRB 011030
  29. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  30. GRB 970828: HST Observations of the Host Galaxy
  31. GRB 000131: HST Detection of the Host Galaxy
  32. GRB 970828: HST Observations of the Host Galaxy
  33. GRB010921, optical observation
  34. GRB 011019 optical observation
  35. GRB011019: Subaru Optical Observations
  36. GRB 011030 I-band Observations
  37. GRB 011030 K-band Observations
  38. GRB010921, optical observations
  39. GRB 011030, WSRT radio observations
  40. GRB011030 - further refinement WFC position
  41. GRB 011030, Radio observations
  42. GRB 011030, R-band observations
  43. BeppoSAX ALERT: Possible X-ray rich GRB011030
  44. GRB 010921: Possible supernova component
  45. GRB011019: NEAT Optical Observations
  46. GRB010921, optical observation at early time
  47. GRB 010921, I-band observations
  48. GRB011019: Optical observations
  49. GRB011019, optical observations
  50. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  51. GRB010921: Spectroscopy of the Host Galaxy
  52. GRB 010921: The afterglow of HETE #1761
  53. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  54. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  55. GRB010923 as seen by BeppoSAX GRBM
  56. GRB010928(=H1770): Localization of a Long GRB by HETE
  57. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  58. GRB010921, negative optical observations
  59. GRB010921 field photometry
  60. GRB010921 Optical Observations
  61. GRB 010921 DPOSS Images Available
  62. IPN triangulation of GRB010921 (=H1761)
  63. H1761: A Bright GRB Detected by HETE
  64. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  65. HETE Trigger #1760 (GRB 010920B?): a new optical source
  66. HETE Trigger #1759 (GRB 010920?) optical observations
  67. GRB001109, Host Galaxy Astrometry
  68. GRB000926, Host Galaxy Observations
  69. GRB001109, Host Galaxy Spectroscopic Observations
  70. Probable SGR or Short Duration GRB Detected by HETE
  71. GRB000926 Host Galaxy Observations
  72. GRB 010222: HST observations -- host galaxy and late-time decay
  73. BeppoSAX/GRBM detection of GRB 010801
  74. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  75. GRB 010222 - WHT BVRI images
  76. GRB 010629 Optical Observations
  77. GRB010629: Optical Observations
  78. GRB010629, optical observations
  79. IPN triangulation of GRB010629
  80. GRB010629: A Burst Localized by HETE
  81. Possible burst from SGR1806-20
  82. IPN detection of SGR1900+14
  83. GRB 00630: Host Galaxy
  84. IPN triangulation of GRB010613
  85. IPN triangulation of GRB010612
  86. HETE Fully-Automated GCN Notices
  87. GRB000301C: Late-time HST/STIS observation
  88. GRB010518: a faint BeppoSAX detection
  89. GRB000418: HST/STIS Second-epoch Observations
  90. GRB010427, Gamma Ray Observations
  91. SGR1900+14
  92. GRB 010222 /corrections to VBT data
  93. Possible precursor to the SGR1900+14 giant burst
  94. IPN Triangulation of the Giant Flare from SGR1900+14
  95. GRB010412, field photometry
  96. GRB 010326b Optical Observations
  97. GRB010412: Optical observations
  98. GRB010412: Optical observations
  99. IPN Triangulation of GRB010412
  100. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002

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