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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"

42627 results found.

  1. GRB011211: BeppoSAX/GRBM data
  2. Optical polarization observations for GRB011211
  3. GRB 011211: Detection of the Probable Host Galaxy
  4. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  5. Color indices of the afterglow of GRB011211
  6. GRB011212: Optical observations at Gunma
  7. GRB 011211, spectrum and optical photometry
  8. GRB 011130, Radio/X-ray Comparison
  9. GRB011212: Optical observations
  10. GRB 011212: optical observation at Asiago
  11. GRB 011211: Evidence for an Optical Break
  12. GRB 011211: TNG Spectroscopic Observations
  13. GRB 011212: optical observation at Oslo (relayed)
  14. GRB 011211: Optical Spectroscopy
  15. GRB 011211, Optical Observations
  16. GRB011212, BVRI field photometry
  17. GRB011211, BVRI field photometry
  18. GRB 011211: BVRi-band photometry
  19. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  20. Fading of the optical source associated of XRF 011211
  21. XMM-Newton observation of GRB011211
  22. GRB 011211 Optical Observations: Likely Afterglow
  23. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  24. GRB 011130: Optical Observations of Chandra Sources
  25. GRB011130 (XRF011130) Chandra Observations
  26. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  27. GRB 011130: Magellan spectroscopy
  28. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  29. GRB011130, optical observations
  30. GRB 011130, K band observations
  31. GRB011130, optical observations
  32. GRB011130 (=XRF011130): Second Revised Localization by HETE
  33. GRB 011130 I-band Observation
  34. GRB011130 (XRF011130) optical observations
  35. GRB011130 (XRF011130) SDSS PT i-band observations
  36. XRF011130: Infrared Observations
  37. GRB011130, Radio Observations
  38. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  39. GRB011130 (=XRF011130), Optical Observations
  40. GRB011130 (=XRF011130): Revised Localization of an X-ray
  41. GRB001109, Radio Monitoring
  42. GRB 011121
  43. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  44. GRB 011121: J-band observations
  45. GRB 011121: NIR observations, host galaxy?
  46. GRB010921 - Milagro GeV/TeV Observations
  47. GRB 011121: HST Scheduled
  48. GRB011121: fainter still
  49. GRB011121: UBRI Observations
  50. GRB011121
  51. GRB 011121: Radio Observations
  52. GRB 011121 J-Band Astrometry
  53. GRB011121: continued decay
  54. GRB 011121: Detection of Bright IR Counterpart
  55. GRB011121: possible redshift, continued decay
  56. GRB011121: fading behavior
  57. GRB011121: possible optical counterpart
  58. GRB011121: BeppoSAX-WFC refined positions
  59. IPN triangulation of GRB011121
  60. BEPPOSAX GRB011121
  61. GRB 011030: TNG K-band observation
  62. XRF011030: J and K band observations
  63. XRF011030: Chandra Observations
  64. GRB 011030: K-band observations
  65. GRB011030: Z-band observations
  66. GRB 011030 R band observations
  67. GRB 011030 I-band Observation
  68. The X-ray Flash 011030 ('GRB 011030')
  69. Non-triggered burst 011030 ("GRB 011030")
  70. The Radio Afterglow from the X-ray Rich GRB 011030
  71. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  72. GRB 970828: HST Observations of the Host Galaxy
  73. GRB 000131: HST Detection of the Host Galaxy
  74. GRB 970828: HST Observations of the Host Galaxy
  75. GRB010921, optical observation
  76. GRB 011019 optical observation
  77. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  78. GRB 011030 I-band Observations
  79. GRB 011030 K-band Observations
  80. GRB010921, optical observations
  81. GRB 011030, WSRT radio observations
  82. GRB011030 - further refinement WFC position
  83. GRB 011030, Radio observations
  84. GRB011030: radio search
  85. GRB 011030, R-band observations
  86. BeppoSAX ALERT: Possible X-ray rich GRB011030
  87. GRB 010921: Possible supernova component
  88. GRB011019: NEAT Optical Observations
  89. GRB011019: ROTSE-III optical observations
  90. GRB010921, optical observation at early time
  91. GRB 010921, I-band observations
  92. GRB011019: Optical observations
  93. GRB011019, optical observations -- correction
  94. GRB011019, optical observations
  95. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  96. GRB010921: Spectroscopy of the Host Galaxy
  97. GRB 010921: The afterglow of HETE #1761
  98. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  99. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  100. GRB010923 as seen by BeppoSAX GRBM

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