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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"
  1. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  2. Fading of the optical source associated of XRF 011211
  3. XMM-Newton observation of GRB011211
  4. GRB 011211 Optical Observations: Likely Afterglow
  5. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  6. GRB011211(=XRF011211): BeppoSAX refined positions
  7. BeppoSAX Alert: GRB011211(=XRF011211)
  8. GRB 011130: Optical Observations of Chandra Sources
  9. GRB 011130: Optical Observations of Chandra sources
  10. GRB011130 (XRF011130) Chandra Observations
  11. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  12. GRB 011130: Magellan spectroscopy
  13. Sub-mm and Centimeter Detections of the Host Galaxy of GRB000418
  14. GRB011130, optical observations
  15. GRB 011130, K band observations
  16. GRB011130, optical observations
  17. GRB011130 (=XRF011130): Second Revised Localization by HETE
  18. GRB 011130 I-band Observation
  19. GRB011130 (XRF011130) optical observations
  20. GRB011130 (XRF011130) SDSS PT i-band observations
  21. XRF011130: Infrared Observations
  22. GRB011130, Radio Observations
  23. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  24. GRB011130 (=XRF011130), Optical Observations
  25. XRF011130: NEAT Optical Observations
  26. GRB011130 (=XRF011130): Revised Localization of an X-ray
  27. GRB001109, Radio Monitoring
  28. GRB 011121: Errata URL
  29. GRB 011121
  30. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  31. GRB 011121: J-band observations
  32. GRB 011121: NIR observations, host galaxy?
  33. GRB010921 - Milagro GeV/TeV Observations
  34. GRB 011121: HST Scheduled
  35. GRB011121: fainter still
  36. Correction: GCN1157 (GRB 011121)
  37. GRB011121: UBRI Observations
  38. GRB011121
  39. GRB 011121: Radio Observations
  40. GRB 011121 J-Band Astrometry
  41. GRB011121: continued decay
  42. GRB 011121: Detection of Bright IR Counterpart
  43. GRB011121: possible redshift, continued decay
  44. GRB011121: fading behavior
  45. GRB011121: possible optical counterpart
  46. GRB011121: BeppoSAX-WFC refined positions
  47. IPN triangulation of GRB011121
  48. BEPPOSAX GRB011121
  49. GRB 011030: TNG K-band observation
  50. XRF011030: J and K band observations
  51. GRB011030, optical observation
  52. XRF011030: Chandra Observations
  53. GRB 011030: K-band observations
  54. GRB011030: Z-band observations
  55. GRB 011030 R band observations
  56. GRB 011030 I-band Observation
  57. The X-ray Flash 011030 ('GRB 011030')
  58. Non-triggered burst 011030 ("GRB 011030")
  59. The Radio Afterglow from the X-ray Rich GRB 011030
  60. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  61. GRB 970828: HST Observations of the Host Galaxy
  62. GRB 000131: HST Detection of the Host Galaxy
  63. GRB 970828: HST Observations of the Host Galaxy
  64. GRB010921, optical observation
  65. GRB 011019 optical observation
  66. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  67. GRB011019: Subaru Optical Observations
  68. GRB 011030 I-band Observations
  69. GRB 011030 K-band Observations
  70. GRB010921, optical observations
  71. GRB 011030, WSRT radio observations
  72. GRB011030 - further refinement WFC position
  73. GRB 011030, Radio observations
  74. GRB011030: radio search
  75. GRB 011030, R-band observations
  76. X-ray rich GRB011030: BeppoSAX refined positions
  77. BeppoSAX ALERT: Possible X-ray rich GRB011030
  78. GRB 010921: Possible supernova component
  79. GRB011019: NEAT Optical Observations
  80. GRB011019: ROTSE-III optical observations
  81. GRB010921, optical observation at early time
  82. GRB 010921, I-band observations
  83. GRB011019: Optical observations
  84. GRB011019, optical observations -- correction
  85. GRB011019, optical observations
  86. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  87. GRB010921: Spectroscopy of the Host Galaxy
  88. GRB 010921: The afterglow of HETE #1761
  89. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  90. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  91. GRB010923 as seen by BeppoSAX GRBM
  92. GRB010928(=H1770): Localization of a Long GRB by HETE
  93. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  94. GRB010921, negative optical observations
  95. GRB010921 field photometry
  96. GRB010921 Optical Observations
  97. GRB 010921 DPOSS Images Available
  98. IPN triangulation of GRB010921 (=H1761)
  99. H1761: A Bright GRB Detected by HETE
  100. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid

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