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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"

27319 results found.

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

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