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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"

32536 results found.

  1. Correction: GCN1157 (GRB 011121)
  2. GRB011121: UBRI Observations
  3. GRB011121
  4. GRB 011121: Radio Observations
  5. GRB 011121 J-Band Astrometry
  6. GRB011121: continued decay
  7. GRB 011121: Detection of Bright IR Counterpart
  8. GRB011121: possible redshift, continued decay
  9. GRB011121: fading behavior
  10. GRB011121: possible optical counterpart
  11. IPN triangulation of GRB011121
  12. GRB 011030: TNG K-band observation
  13. XRF011030: J and K band observations
  14. XRF011030: Chandra Observations
  15. GRB 011030: K-band observations
  16. GRB011030: Z-band observations
  17. GRB 011030 I-band Observation
  18. The X-ray Flash 011030 ('GRB 011030')
  19. The Radio Afterglow from the X-ray Rich GRB 011030
  20. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  21. GRB 000131: HST Detection of the Host Galaxy
  22. GRB 011019 optical observation
  23. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  24. GRB011019: Subaru Optical Observations
  25. GRB 011030 I-band Observations
  26. GRB 011030 K-band Observations
  27. GRB010921, optical observations
  28. GRB 011030, WSRT radio observations
  29. GRB011030 - further refinement WFC position
  30. GRB 011030, Radio observations
  31. GRB011030: radio search
  32. GRB 011030, R-band observations
  33. BeppoSAX ALERT: Possible X-ray rich GRB011030
  34. GRB 010921: Possible supernova component
  35. GRB011019: ROTSE-III optical observations
  36. GRB 010921, I-band observations
  37. GRB011019: Optical observations
  38. GRB011019, optical observations -- correction
  39. GRB011019, optical observations
  40. GRB010921: Spectroscopy of the Host Galaxy
  41. GRB 010921: The afterglow of HETE #1761
  42. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  43. GRB010923 as seen by BeppoSAX GRBM
  44. GRB010928(=H1770): Localization of a Long GRB by HETE
  45. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  46. GRB010921, negative optical observations
  47. GRB010921 field photometry
  48. GRB 010921 DPOSS Images Available
  49. IPN triangulation of GRB010921 (=H1761)
  50. H1761: A Bright GRB Detected by HETE
  51. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  52. GRB001109, Host Galaxy Astrometry
  53. GRB000926, Host Galaxy Observations
  54. GRB001109, Host Galaxy Spectroscopic Observations
  55. Probable SGR or Short Duration GRB Detected by HETE
  56. GCN and HETE status
  57. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  58. GRB 010222 - WHT BVRI images
  59. SGR1900+14 burst seen by HETE: BeppoSAX data
  60. GRB 010629 Optical Observations
  61. GRB010629: Optical Observations
  62. SGR1900+14: High Fluence Burst Localized by HETE
  63. GRB010629, optical observations
  64. IPN triangulation of GRB010629
  65. SGR1900+14: Second Burst Localized by HETE
  66. SGR1900+14: A Burst Localized by HETE
  67. Possible burst from SGR1806-20
  68. SGR1806-20: A Second, Intense Burst Localized by HETE
  69. IPN triangulation of GRB010613
  70. IPN triangulation of GRB010612
  71. IPN triangulation of GRB010612
  72. HETE Fully-Automated GCN Notices
  73. GRB000301C: Late-time HST/STIS observation
  74. GRB000418: HST/STIS Second-epoch Observations
  75. X-ray precursors to the large flare from SGR 1900+14
  76. GRB010214, optical observations
  77. SGR 1900+14: No evidence of extended X-ray emission
  78. SGR 1900+14 : RXTE observations
  79. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  80. SGR1900+14 - correction
  81. SGR1900+14
  82. SGR 1900+14: Correction to GCN 1049
  83. Millimeter observation of SGR 1900+14
  84. SGR 1900+14: Detection of extended X-ray emission
  85. Chandra Observations of SGR 1900+14
  86. SGR 1900+14, Chandra observations
  87. Chandra Observations of SGR 1900+14
  88. Possible precursor to the SGR1900+14 giant burst
  89. SGR1900+14, I-band observations
  90. IPN Triangulation of the Giant Flare from SGR1900+14
  91. GRB 010326b Optical Observations
  92. GRB010412: Optical observations
  93. GRB010412: Optical observations
  94. IPN Triangulation of GRB010412
  95. GRB Observation Report
  96. REVISED LOCATION OF GRB010326A
  97. GRB 980326: Late-time HST/STIS observations
  98. GRB010324, field photometry
  99. GRB010326B, field photometry
  100. GRB010326, field photometry

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