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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"

42193 results found.

  1. GRB020127 Optical Observations -- Erratum to GCN 1230
  2. GRB010921 Optical Observations
  3. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  4. GRB020124: Optical observations
  5. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  6. GRB020124: Optical observations
  7. GRB 020124: Optical observations
  8. GRB 020124 Optical Observations
  9. IPN triangulation of GRB020124 (HETE 1896)
  10. IPN observations of SGR1806-20
  11. GRB 020124: Optical afterglow
  12. GRB020124(=H1896): Localization of a Long GRB by HETE
  13. HETE 1896: Optical observations
  14. GRB optical counterpart candidate in GCN 1217 is M dwarf
  15. Possible optical counterpart to a GRB
  16. GRB011212, Optical Observations
  17. GRB011211: BeppoSAX/GRBM data
  18. Optical polarization observations for GRB011211
  19. GRB 011211: Detection of the Probable Host Galaxy
  20. GRB 011130 and GRB 011212 - Milagro GeV/TeV Observations
  21. Color indices of the afterglow of GRB011211
  22. GRB011212: Optical observations at Gunma
  23. GRB 011211, spectrum and optical photometry
  24. GRB 011130: Optical Observations of X-ray and Radio Sources
  25. GRB 011130, Radio/X-ray Comparison
  26. GRB011212: Optical observations
  27. GRB 011212: optical observation at Asiago
  28. GRB 011211: Evidence for an Optical Break
  29. GRB 011211: TNG Spectroscopic Observations
  30. optical follow-up of GRB(XRF) 011211
  31. GRB 011212: optical observation at Oslo (relayed)
  32. GRB 011211: Optical Spectroscopy
  33. GRB 011211, Optical Observations
  34. GRB011212, BVRI field photometry
  35. GRB011211, BVRI field photometry
  36. GRB011212: Optical observations
  37. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  38. Fading of the optical source associated of XRF 011211
  39. XMM-Newton observation of GRB011211
  40. GRB 011211 Optical Observations: Likely Afterglow
  41. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  42. BeppoSAX Alert: GRB011211(=XRF011211)
  43. GRB 011130: Optical Observations of Chandra Sources
  44. GRB 011130: Optical Observations of Chandra sources
  45. GRB011130 (XRF011130) Chandra Observations
  46. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  47. GRB 011130: Magellan spectroscopy
  48. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  49. GRB011130, optical observations
  50. GRB 011130, K band observations
  51. GRB011130, optical observations
  52. GRB011130 (=XRF011130): Second Revised Localization by HETE
  53. GRB 011130 I-band Observation
  54. GRB011130 (XRF011130) optical observations
  55. GRB011130 (XRF011130) SDSS PT i-band observations
  56. XRF011130: Infrared Observations
  57. GRB011130, Radio Observations
  58. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  59. GRB011130 (=XRF011130), Optical Observations
  60. XRF011130: NEAT Optical Observations
  61. GRB011130 (=XRF011130): Revised Localization of an X-ray
  62. GRB001109, Radio Monitoring
  63. GRB 011121
  64. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  65. GRB 011121: J-band observations
  66. GRB 011121: NIR observations, host galaxy?
  67. GRB010921 - Milagro GeV/TeV Observations
  68. GRB 011121: HST Scheduled
  69. GRB011121: fainter still
  70. GRB011121: UBRI Observations
  71. GRB011121
  72. GRB 011121: Radio Observations
  73. GRB 011121 J-Band Astrometry
  74. GRB011121: continued decay
  75. GRB 011121: Detection of Bright IR Counterpart
  76. GRB011121: possible redshift, continued decay
  77. GRB011121: fading behavior
  78. GRB011121: possible optical counterpart
  79. GRB 011030: TNG K-band observation
  80. XRF011030: J and K band observations
  81. GRB011030, optical observation
  82. XRF011030: Chandra Observations
  83. GRB 011030: K-band observations
  84. GRB011030: Z-band observations
  85. GRB 011030 R band observations
  86. GRB 011030 I-band Observation
  87. The X-ray Flash 011030 ('GRB 011030')
  88. Non-triggered burst 011030 ("GRB 011030")
  89. The Radio Afterglow from the X-ray Rich GRB 011030
  90. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  91. GRB 970828: HST Observations of the Host Galaxy
  92. GRB 000131: HST Detection of the Host Galaxy
  93. GRB 970828: HST Observations of the Host Galaxy
  94. GRB010921, optical observation
  95. GRB 011019 optical observation
  96. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  97. GRB011019: Subaru Optical Observations
  98. GRB 011030 I-band Observations
  99. GRB 011030 K-band Observations
  100. GRB010921, optical observations

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