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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"

36042 results found.

  1. GRB 011211: TNG Spectroscopic Observations
  2. optical follow-up of GRB(XRF) 011211
  3. GRB 011212: optical observation at Oslo (relayed)
  4. GRB 011211: Optical Spectroscopy
  5. GRB 011211, Optical Observations
  6. GRB011212, BVRI field photometry
  7. GRB011211, BVRI field photometry
  8. GRB011212: Optical observations
  9. GRB 011211: BVRi-band photometry
  10. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  11. Fading of the optical source associated of XRF 011211
  12. GRB 011211 Optical Observations: Likely Afterglow
  13. BeppoSAX Alert: GRB011211(=XRF011211)
  14. GRB 011130: Optical Observations of Chandra Sources
  15. GRB 011130: Optical Observations of Chandra sources
  16. GRB 011130: Magellan spectroscopy
  17. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  18. GRB011130, optical observations
  19. GRB 011130, K band observations
  20. GRB011130, optical observations
  21. GRB 011130 I-band Observation
  22. GRB011130 (XRF011130) optical observations
  23. GRB011130 (XRF011130) SDSS PT i-band observations
  24. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  25. XRF011130: NEAT Optical Observations
  26. GRB011130 (=XRF011130): Revised Localization of an X-ray
  27. GRB001109, Radio Monitoring
  28. GRB 011121: Errata URL
  29. GRB 011121
  30. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  31. GRB 011121: J-band observations
  32. GRB 011121: NIR observations, host galaxy?
  33. GRB 011121: HST Scheduled
  34. GRB011121: fainter still
  35. Correction: GCN1157 (GRB 011121)
  36. GRB 011121: Radio Observations
  37. GRB 011121 J-Band Astrometry
  38. GRB011121: continued decay
  39. GRB 011121: Detection of Bright IR Counterpart
  40. GRB011121: possible redshift, continued decay
  41. IPN triangulation of GRB011121
  42. BEPPOSAX GRB011121
  43. GRB 011030: TNG K-band observation
  44. XRF011030: Chandra Observations
  45. GRB 011030: K-band observations
  46. GRB 011030 R band observations
  47. GRB 011030 I-band Observation
  48. The X-ray Flash 011030 ('GRB 011030')
  49. Non-triggered burst 011030 ("GRB 011030")
  50. The Radio Afterglow from the X-ray Rich GRB 011030
  51. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  52. GRB 970828: HST Observations of the Host Galaxy
  53. GRB 000131: HST Detection of the Host Galaxy
  54. GRB 970828: HST Observations of the Host Galaxy
  55. GRB010921, optical observation
  56. GRB 011019 optical observation
  57. GRB011019: Subaru Optical Observations
  58. GRB 011030 I-band Observations
  59. GRB 011030 K-band Observations
  60. GRB010921, optical observations
  61. GRB 011030, WSRT radio observations
  62. GRB011030 - further refinement WFC position
  63. GRB 011030, Radio observations
  64. GRB 011030, R-band observations
  65. BeppoSAX ALERT: Possible X-ray rich GRB011030
  66. GRB 010921: Possible supernova component
  67. GRB011019: NEAT Optical Observations
  68. GRB010921, optical observation at early time
  69. GRB 010921, I-band observations
  70. GRB011019: Optical observations
  71. GRB011019, optical observations
  72. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  73. GRB010921: Spectroscopy of the Host Galaxy
  74. GRB 010921: The afterglow of HETE #1761
  75. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  76. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  77. GRB010923 as seen by BeppoSAX GRBM
  78. GRB010928(=H1770): Localization of a Long GRB by HETE
  79. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  80. GRB010921, negative optical observations
  81. GRB010921 field photometry
  82. GRB010921 Optical Observations
  83. GRB 010921 DPOSS Images Available
  84. IPN triangulation of GRB010921 (=H1761)
  85. H1761: A Bright GRB Detected by HETE
  86. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  87. HETE Trigger #1760 (GRB 010920B?): a new optical source
  88. HETE Trigger #1759 (GRB 010920?) optical observations
  89. GRB001109, Host Galaxy Astrometry
  90. GRB000926, Host Galaxy Observations
  91. GRB001109, Host Galaxy Spectroscopic Observations
  92. Probable SGR or Short Duration GRB Detected by HETE
  93. GRB000926 Host Galaxy Observations
  94. GRB 010222: HST observations -- host galaxy and late-time decay
  95. BeppoSAX/GRBM detection of GRB 010801
  96. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  97. GRB 010222 - WHT BVRI images
  98. GRB 010629 Optical Observations
  99. GRB010629: Optical Observations
  100. GRB010629, optical observations

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