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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"

27118 results found.

  1. GRB011130 (=XRF011130): Second Revised Localization by HETE
  2. GRB011130 (XRF011130) SDSS PT i-band observations
  3. XRF011130: Infrared Observations
  4. GRB 011121
  5. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  6. GRB 011121: J-band observations
  7. GRB 011121: NIR observations, host galaxy?
  8. GRB011121: UBRI Observations
  9. GRB 011121 J-Band Astrometry
  10. GRB 011121: Detection of Bright IR Counterpart
  11. GRB011121: possible redshift, continued decay
  12. GRB 011030: TNG K-band observation
  13. XRF011030: J and K band observations
  14. XRF011030: Chandra Observations
  15. GRB011030: Z-band observations
  16. GRB 011030 R band observations
  17. GRB 011030 I-band Observation
  18. The X-ray Flash 011030 ('GRB 011030')
  19. Non-triggered burst 011030 ("GRB 011030")
  20. The Radio Afterglow from the X-ray Rich GRB 011030
  21. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  22. GRB 970828: HST Observations of the Host Galaxy
  23. GRB 000131: HST Detection of the Host Galaxy
  24. GRB 970828: HST Observations of the Host Galaxy
  25. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  26. GRB011019: Subaru Optical Observations
  27. GRB 011030 I-band Observations
  28. GRB 011030 K-band Observations
  29. GRB010921, optical observations
  30. GRB011030 - further refinement WFC position
  31. GRB 011030, Radio observations
  32. GRB011030: radio search
  33. GRB 010921: Possible supernova component
  34. GRB010921, optical observation at early time
  35. GRB 010921, I-band observations
  36. GRB011019, optical observations
  37. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  38. GRB 010921: The afterglow of HETE #1761
  39. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  40. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  41. GRB010923 as seen by BeppoSAX GRBM
  42. GRB010928(=H1770): Localization of a Long GRB by HETE
  43. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  44. GRB010921, negative optical observations
  45. GRB010921 field photometry
  46. H1761: A Bright GRB Detected by HETE
  47. GRB000926, Host Galaxy Observations
  48. GRB001109, Host Galaxy Spectroscopic Observations
  49. Probable SGR or Short Duration GRB Detected by HETE
  50. GCN and HETE status
  51. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  52. GRB 010222 - WHT BVRI images
  53. SGR1900+14 burst seen by HETE: BeppoSAX data
  54. GRB 010629 Optical Observations
  55. SGR1900+14: High Fluence Burst Localized by HETE
  56. GRB010629, optical observations
  57. GRB010629: A Burst Localized by HETE
  58. SGR1900+14: Second Burst Localized by HETE
  59. SGR1900+14: A Burst Localized by HETE
  60. SGR1806-20: A Second, Intense Burst Localized by HETE
  61. SGR1806-20: Localization by HETE
  62. HETE Fully-Automated GCN Notices
  63. GRB000301C: Late-time HST/STIS observation
  64. GRB010518: a faint BeppoSAX detection
  65. GRB000418: HST/STIS Second-epoch Observations
  66. X-ray precursors to the large flare from SGR 1900+14
  67. GRB010427, Gamma Ray Observations
  68. SGR 1900+14: No evidence of extended X-ray emission
  69. SGR 1900+14 : RXTE observations
  70. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  71. SGR 1900+14: Correction to GCN 1049
  72. GRB 010222 /corrections to VBT data
  73. Millimeter observation of SGR 1900+14
  74. SGR 1900+14: Detection of extended X-ray emission
  75. SGR 1900+14, Chandra observations
  76. SGR1900+14, I-band observations
  77. GRB010412, field photometry
  78. Giant flare from SGR1900+14
  79. GRB 010326b Optical Observations
  80. GRB010412: BeppoSAX GRBM and WFC observations
  81. GRB010324, revised field photometry
  82. REVISED LOCATION OF GRB010326A
  83. GRB 980326: Late-time HST/STIS observations
  84. GRB010324, field photometry
  85. GRB010326B, field photometry
  86. GRB010326, field photometry
  87. GRB010220, field photometry
  88. Further Optical Observations of GRB 010324
  89. GRB010222, CXO X-ray observations
  90. GRB010324, optical observations
  91. GRB010326B: Localization by HETE (2nd GRB for this date)
  92. GRB 010326 optical observations
  93. GRB010326: Refined Localization by HETE
  94. GRB010326: Localization by HETE
  95. Optical Observations of GRB 010324
  96. GRB010222, late-time optical observation
  97. Support extension to the BeppoSAX mission
  98. GRB 010222 - HEGRA GeV/TeV Observations
  99. GRB010222: Chandra X-ray Observatory Observation
  100. GRB010222: Sub-millimeter vanishing act

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