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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"

32688 results found.

  1. IPN triangulation of GRB020124 (HETE 1896)
  2. GRB 020124: Optical afterglow
  3. GRB020124(=H1896): Localization of a Long GRB by HETE
  4. GRB optical counterpart candidate in GCN 1217 is M dwarf
  5. GRB011212, Optical Observations
  6. GRB011211: BeppoSAX/GRBM data
  7. Optical polarization observations for GRB011211
  8. Color indices of the afterglow of GRB011211
  9. GRB011212: Optical observations at Gunma
  10. GRB 011211, spectrum and optical photometry
  11. GRB 011130: Optical Observations of X-ray and Radio Sources
  12. GRB 011130, Radio/X-ray Comparison
  13. GRB011212: Optical observations
  14. GRB 011212: optical observation at Asiago
  15. GRB 011211: Evidence for an Optical Break
  16. GRB 011211: TNG Spectroscopic Observations
  17. optical follow-up of GRB(XRF) 011211
  18. GRB 011212: optical observation at Oslo (relayed)
  19. GRB 011211: Optical Spectroscopy
  20. GRB 011211, Optical Observations
  21. GRB011212, BVRI field photometry
  22. GRB011211, BVRI field photometry
  23. GRB011212: Optical observations
  24. GRB 011211: BVRi-band photometry
  25. Fading of the optical source associated of XRF 011211
  26. XMM-Newton observation of GRB011211
  27. GRB 011211 Optical Observations: Likely Afterglow
  28. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  29. GRB 011130: Optical Observations of Chandra Sources
  30. GRB 011130: Optical Observations of Chandra sources
  31. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  32. GRB 011130: Magellan spectroscopy
  33. GRB011130, optical observations
  34. GRB011130, optical observations
  35. GRB011130 (=XRF011130): Second Revised Localization by HETE
  36. GRB 011130 I-band Observation
  37. GRB011130 (XRF011130) optical observations
  38. GRB011130 (XRF011130) SDSS PT i-band observations
  39. XRF011130: Infrared Observations
  40. GRB011130, Radio Observations
  41. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  42. GRB011130 (=XRF011130), Optical Observations
  43. XRF011130: NEAT Optical Observations
  44. GRB011130 (=XRF011130): Revised Localization of an X-ray
  45. GRB001109, Radio Monitoring
  46. GRB 011121: Errata URL
  47. GRB 011121
  48. GRB 011121: J-band observations
  49. GRB 011121: NIR observations, host galaxy?
  50. GRB010921 - Milagro GeV/TeV Observations
  51. GRB 011121: HST Scheduled
  52. GRB011121: fainter still
  53. Correction: GCN1157 (GRB 011121)
  54. GRB011121: UBRI Observations
  55. GRB011121
  56. GRB 011121: Radio Observations
  57. GRB 011121 J-Band Astrometry
  58. GRB011121: continued decay
  59. GRB 011121: Detection of Bright IR Counterpart
  60. GRB011121: possible redshift, continued decay
  61. GRB011121: fading behavior
  62. GRB011121: possible optical counterpart
  63. IPN triangulation of GRB011121
  64. GRB 011030: TNG K-band observation
  65. XRF011030: J and K band observations
  66. XRF011030: Chandra Observations
  67. GRB 011030: K-band observations
  68. GRB011030: Z-band observations
  69. GRB 011030 I-band Observation
  70. The X-ray Flash 011030 ('GRB 011030')
  71. The Radio Afterglow from the X-ray Rich GRB 011030
  72. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  73. GRB 000131: HST Detection of the Host Galaxy
  74. GRB 011019 optical observation
  75. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  76. GRB011019: Subaru Optical Observations
  77. GRB 011030 I-band Observations
  78. GRB 011030 K-band Observations
  79. GRB010921, optical observations
  80. GRB 011030, WSRT radio observations
  81. GRB011030 - further refinement WFC position
  82. GRB 011030, Radio observations
  83. GRB011030: radio search
  84. GRB 011030, R-band observations
  85. BeppoSAX ALERT: Possible X-ray rich GRB011030
  86. GRB 010921: Possible supernova component
  87. GRB011019: ROTSE-III optical observations
  88. GRB 010921, I-band observations
  89. GRB011019: Optical observations
  90. GRB011019, optical observations -- correction
  91. GRB011019, optical observations
  92. GRB010921: Spectroscopy of the Host Galaxy
  93. GRB 010921: The afterglow of HETE #1761
  94. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  95. GRB010923 as seen by BeppoSAX GRBM
  96. GRB010928(=H1770): Localization of a Long GRB by HETE
  97. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  98. GRB010921, negative optical observations
  99. GRB010921 field photometry
  100. GRB 010921 DPOSS Images Available

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