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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"

35934 results found.

  1. GRB 011211, Optical Observations
  2. GRB011212, BVRI field photometry
  3. GRB011211, BVRI field photometry
  4. GRB011212: Optical observations
  5. GRB 011211: BVRi-band photometry
  6. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  7. Fading of the optical source associated of XRF 011211
  8. GRB 011211 Optical Observations: Likely Afterglow
  9. BeppoSAX Alert: GRB011211(=XRF011211)
  10. GRB 011130: Optical Observations of Chandra Sources
  11. GRB 011130: Optical Observations of Chandra sources
  12. GRB 011130: Magellan spectroscopy
  13. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  14. GRB011130, optical observations
  15. GRB 011130, K band observations
  16. GRB011130, optical observations
  17. GRB 011130 I-band Observation
  18. GRB011130 (XRF011130) optical observations
  19. GRB011130 (XRF011130) SDSS PT i-band observations
  20. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  21. XRF011130: NEAT Optical Observations
  22. GRB011130 (=XRF011130): Revised Localization of an X-ray
  23. GRB001109, Radio Monitoring
  24. GRB 011121: Errata URL
  25. GRB 011121
  26. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  27. GRB 011121: J-band observations
  28. GRB 011121: NIR observations, host galaxy?
  29. GRB 011121: HST Scheduled
  30. GRB011121: fainter still
  31. Correction: GCN1157 (GRB 011121)
  32. GRB 011121: Radio Observations
  33. GRB 011121 J-Band Astrometry
  34. GRB011121: continued decay
  35. GRB 011121: Detection of Bright IR Counterpart
  36. GRB011121: possible redshift, continued decay
  37. IPN triangulation of GRB011121
  38. BEPPOSAX GRB011121
  39. GRB 011030: TNG K-band observation
  40. XRF011030: Chandra Observations
  41. GRB 011030: K-band observations
  42. GRB 011030 R band observations
  43. GRB 011030 I-band Observation
  44. The X-ray Flash 011030 ('GRB 011030')
  45. Non-triggered burst 011030 ("GRB 011030")
  46. The Radio Afterglow from the X-ray Rich GRB 011030
  47. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  48. GRB 970828: HST Observations of the Host Galaxy
  49. GRB 000131: HST Detection of the Host Galaxy
  50. GRB 970828: HST Observations of the Host Galaxy
  51. GRB010921, optical observation
  52. GRB 011019 optical observation
  53. GRB011019: Subaru Optical Observations
  54. GRB 011030 I-band Observations
  55. GRB 011030 K-band Observations
  56. GRB010921, optical observations
  57. GRB 011030, WSRT radio observations
  58. GRB011030 - further refinement WFC position
  59. GRB 011030, Radio observations
  60. GRB 011030, R-band observations
  61. BeppoSAX ALERT: Possible X-ray rich GRB011030
  62. GRB 010921: Possible supernova component
  63. GRB011019: NEAT Optical Observations
  64. GRB010921, optical observation at early time
  65. GRB 010921, I-band observations
  66. GRB011019: Optical observations
  67. GRB011019, optical observations
  68. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  69. GRB010921: Spectroscopy of the Host Galaxy
  70. GRB 010921: The afterglow of HETE #1761
  71. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  72. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  73. GRB010923 as seen by BeppoSAX GRBM
  74. GRB010928(=H1770): Localization of a Long GRB by HETE
  75. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  76. GRB010921, negative optical observations
  77. GRB010921 field photometry
  78. GRB010921 Optical Observations
  79. GRB 010921 DPOSS Images Available
  80. IPN triangulation of GRB010921 (=H1761)
  81. H1761: A Bright GRB Detected by HETE
  82. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  83. HETE Trigger #1760 (GRB 010920B?): a new optical source
  84. HETE Trigger #1759 (GRB 010920?) optical observations
  85. GRB001109, Host Galaxy Astrometry
  86. GRB000926, Host Galaxy Observations
  87. GRB001109, Host Galaxy Spectroscopic Observations
  88. Probable SGR or Short Duration GRB Detected by HETE
  89. GRB000926 Host Galaxy Observations
  90. GRB 010222: HST observations -- host galaxy and late-time decay
  91. BeppoSAX/GRBM detection of GRB 010801
  92. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  93. GRB 010222 - WHT BVRI images
  94. GRB 010629 Optical Observations
  95. GRB010629: Optical Observations
  96. GRB010629, optical observations
  97. IPN triangulation of GRB010629
  98. GRB010629: A Burst Localized by HETE
  99. Possible burst from SGR1806-20
  100. IPN detection of SGR1900+14

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