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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"

23577 results found.

  1. GRB011211: BeppoSAX/GRBM data
  2. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  3. GRB011212: Optical observations at Gunma
  4. GRB 011211, spectrum and optical photometry
  5. GRB 011130, Radio/X-ray Comparison
  6. GRB011212: Optical observations
  7. GRB 011212: optical observation at Asiago
  8. GRB 011211: Evidence for an Optical Break
  9. GRB 011211: TNG Spectroscopic Observations
  10. optical follow-up of GRB(XRF) 011211
  11. GRB 011212: optical observation at Oslo (relayed)
  12. GRB 011211: Optical Spectroscopy
  13. GRB 011211, Optical Observations
  14. GRB011212, BVRI field photometry
  15. GRB011211, BVRI field photometry
  16. GRB011212: Optical observations
  17. GRB 011211: BVRi-band photometry
  18. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  19. XMM-Newton observation of GRB011211
  20. GRB 011211 Optical Observations: Likely Afterglow
  21. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  22. GRB 011130: Magellan spectroscopy
  23. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  24. GRB011130, optical observations
  25. GRB011130, optical observations
  26. GRB011130 (=XRF011130): Second Revised Localization by HETE
  27. GRB011130 (XRF011130) optical observations
  28. GRB011130 (XRF011130) SDSS PT i-band observations
  29. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  30. GRB011130 (=XRF011130), Optical Observations
  31. XRF011130: NEAT Optical Observations
  32. GRB011130 (=XRF011130): Revised Localization of an X-ray
  33. GRB 011121
  34. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  35. GRB 011121: J-band observations
  36. GRB011121: UBRI Observations
  37. GRB011121
  38. GRB 011121: Radio Observations
  39. GRB011121: possible redshift, continued decay
  40. GRB011121: fading behavior
  41. GRB011121: possible optical counterpart
  42. IPN triangulation of GRB011121
  43. GRB 011030: TNG K-band observation
  44. GRB011030, optical observation
  45. GRB 011030: K-band observations
  46. GRB011030: Z-band observations
  47. Non-triggered burst 011030 ("GRB 011030")
  48. GRB010921, optical observation
  49. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  50. GRB011019: Subaru Optical Observations
  51. GRB010921, optical observations
  52. GRB011030: radio search
  53. GRB 011030, R-band observations
  54. GRB011019: NEAT Optical Observations
  55. GRB011019: ROTSE-III optical observations
  56. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  57. GRB010921: Spectroscopy of the Host Galaxy
  58. GRB 010921: The afterglow of HETE #1761
  59. GRB010923 as seen by BeppoSAX GRBM
  60. GRB010928(=H1770): Localization of a Long GRB by HETE
  61. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  62. GRB010921 field photometry
  63. GRB010921 Optical Observations
  64. IPN triangulation of GRB010921 (=H1761)
  65. H1761: A Bright GRB Detected by HETE
  66. GRB000926, Host Galaxy Observations
  67. GRB001109, Host Galaxy Spectroscopic Observations
  68. Probable SGR or Short Duration GRB Detected by HETE
  69. GRB000926 Host Galaxy Observations
  70. GRB 010222: HST observations -- host galaxy and late-time decay
  71. BeppoSAX/GRBM detection of GRB 010801
  72. GCN and HETE status
  73. BeppoSAX/GRBM detection of GRB010728
  74. GRB 010222 - WHT BVRI images
  75. SGR1900+14 burst seen by HETE: BeppoSAX data
  76. GRB 010629 Optical Observations
  77. SGR1900+14: High Fluence Burst Localized by HETE
  78. IPN triangulation of GRB010629
  79. GRB010629: A Burst Localized by HETE
  80. SGR1900+14: Second Burst Localized by HETE
  81. SGR1900+14: A Burst Localized by HETE
  82. Possible burst from SGR1806-20
  83. IPN detection of SGR1900+14
  84. SGR1806-20: A Second, Intense Burst Localized by HETE
  85. SGR1806-20: Localization by HETE
  86. GRB000418: HST/STIS Second-epoch Observations
  87. X-ray precursors to the large flare from SGR 1900+14
  88. GRB010427, Gamma Ray Observations
  89. SGR 1900+14 : RXTE observations
  90. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  91. SGR1900+14
  92. GRB 010222 /corrections to VBT data
  93. Millimeter observation of SGR 1900+14
  94. Chandra Observations of SGR 1900+14
  95. Chandra Observations of SGR 1900+14
  96. Possible precursor to the SGR1900+14 giant burst
  97. IPN Triangulation of the Giant Flare from SGR1900+14
  98. GRB010412, field photometry
  99. GRB010412: BeppoSAX GRBM and WFC observations
  100. IPN Triangulation of GRB010412

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