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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"

36149 results found.

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

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