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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

16023 results found.

  1. GRB020305: Properties of the Candidate Optical Afterglow
  2. GRB 011121: HST Observations reveal an intermediate-time multicolor
  3. GRB020305: Subaru Optical Observations
  4. GRB 020305: Optical observations
  5. XRF/GRB 011030: Detection of the Probable Host Galaxy
  6. GRB 020305: Candidate optical afterglow
  7. Type Ic SN2002bl (SN/GRB?) Radio Observations
  8. GRB020305, optical observations
  9. GRB020305: Optical Observations
  10. IPN triangulation of GRB020305 (HETE 1939)
  11. GRB020305 (=H1939): Localization of a GRB by HETE
  12. GRB 020305: Optical observations
  13. HST Imaging of the afterglow and host of GRB 011121
  14. GRB020124 BVRI field photometry
  15. GRB020127: Palomar and VLA Observations of Possible Counterparts
  16. SN2002ap (SN/GRB?) optical spectrographic observations
  17. GRB020127 Optical Observations
  18. Type Ib/c SN2002ap (SN/GRB?)
  19. Type Ib/c SN2002ap (SN/GRB?) Radio Observations
  20. GRB020124, optical observations
  21. GRB020127: Optical observations
  22. IPN triangulation of GRB020127 (=H1902)
  23. GRB020127 Optical Observations -- Erratum to GCN 1230
  24. GRB010921 Optical Observations
  25. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  26. GRB020124: Optical observations
  27. VLT observations of GRB 020124: The fading optical/near-infrared afterglow
  28. GRB020124: Optical observations
  29. GRB 020124: Optical observations
  30. GRB 020124 Optical Observations
  31. IPN triangulation of GRB020124 (HETE 1896)
  32. GRB 020124: Optical afterglow
  33. GRB020124(=H1896): Localization of a Long GRB by HETE
  34. HETE 1896: Optical observations
  35. GRB optical counterpart candidate in GCN 1217 is M dwarf
  36. Possible optical counterpart to a GRB
  37. GRB011212, Optical Observations
  38. Optical polarization observations for GRB011211
  39. Color indices of the afterglow of GRB011211
  40. GRB011212: Optical observations at Gunma
  41. GRB 011211, spectrum and optical photometry
  42. GRB 011130: Optical Observations of X-ray and Radio Sources
  43. GRB011212: Optical observations
  44. GRB 011212: optical observation at Asiago
  45. GRB 011211: Evidence for an Optical Break
  46. optical follow-up of GRB(XRF) 011211
  47. GRB 011212: optical observation at Oslo (relayed)
  48. GRB 011211: Optical Spectroscopy
  49. GRB 011211, Optical Observations
  50. GRB011212, BVRI field photometry
  51. GRB011211, BVRI field photometry
  52. GRB011212: Optical observations
  53. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  54. Fading of the optical source associated of XRF 011211
  55. GRB 011211 Optical Observations: Likely Afterglow
  56. GRB 011130: Optical Observations of Chandra Sources
  57. GRB 011130: Optical Observations of Chandra sources
  58. GRB 011130: Magellan spectroscopy
  59. GRB011130, optical observations
  60. GRB 011130, K band observations
  61. GRB011130, optical observations
  62. GRB011130 (=XRF011130): Second Revised Localization by HETE
  63. GRB 011130 I-band Observation
  64. GRB011130 (XRF011130) optical observations
  65. XRF011130: Infrared Observations
  66. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  67. GRB011130 (=XRF011130), Optical Observations
  68. XRF011130: NEAT Optical Observations
  69. GRB011130 (=XRF011130): Revised Localization of an X-ray
  70. GRB001109, Radio Monitoring
  71. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  72. GRB 011121: J-band observations
  73. GRB 011121: HST Scheduled
  74. GRB011121: UBRI Observations
  75. GRB 011121: Radio Observations
  76. GRB 011121 J-Band Astrometry
  77. GRB011121: fading behavior
  78. GRB011121: possible optical counterpart
  79. GRB011030, optical observation
  80. GRB 011030 I-band Observation
  81. The X-ray Flash 011030 ('GRB 011030')
  82. Non-triggered burst 011030 ("GRB 011030")
  83. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  84. GRB 970828: HST Observations of the Host Galaxy
  85. GRB 000131: HST Detection of the Host Galaxy
  86. GRB 970828: HST Observations of the Host Galaxy
  87. GRB010921, optical observation
  88. GRB 011019 optical observation
  89. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  90. GRB011019: Subaru Optical Observations
  91. GRB010921, optical observations
  92. GRB 011030, R-band observations
  93. GRB 010921: Possible supernova component
  94. GRB011019: NEAT Optical Observations
  95. GRB011019: ROTSE-III optical observations
  96. GRB010921, optical observation at early time
  97. GRB011019: Optical observations
  98. GRB011019, optical observations -- correction
  99. GRB011019, optical observations
  100. GRB011019: A Faint, X-ray Rich GRB localized by HETE

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