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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"

36036 results found.

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

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