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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"

27037 results found.

  1. GRB 011130 I-band Observation
  2. GRB011130 (XRF011130) optical observations
  3. GRB011130 (XRF011130) SDSS PT i-band observations
  4. Detection of the X-ray afterglow of GRB011121 by BeppoSAX
  5. GRB011130 (=XRF011130), Optical Observations
  6. GRB011130 (=XRF011130): Revised Localization of an X-ray
  7. GRB001109, Radio Monitoring
  8. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  9. GRB 011121: J-band observations
  10. GRB011121: UBRI Observations
  11. GRB011121
  12. GRB 011121: Radio Observations
  13. GRB 011121 J-Band Astrometry
  14. GRB 011121: Detection of Bright IR Counterpart
  15. BEPPOSAX GRB011121
  16. GRB 011030: TNG K-band observation
  17. XRF011030: J and K band observations
  18. GRB011030, optical observation
  19. XRF011030: Chandra Observations
  20. GRB 011030: K-band observations
  21. GRB011030: Z-band observations
  22. The X-ray Flash 011030 ('GRB 011030')
  23. The Radio Afterglow from the X-ray Rich GRB 011030
  24. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  25. GRB 970828: HST Observations of the Host Galaxy
  26. GRB 000131: HST Detection of the Host Galaxy
  27. GRB 970828: HST Observations of the Host Galaxy
  28. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  29. GRB010921, optical observations
  30. GRB 011030, Radio observations
  31. GRB011030: radio search
  32. X-ray rich GRB011030: BeppoSAX refined positions
  33. BeppoSAX ALERT: Possible X-ray rich GRB011030
  34. GRB 010921: Possible supernova component
  35. GRB011019: ROTSE-III optical observations
  36. GRB 010921, I-band observations
  37. GRB011019: Optical observations
  38. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  39. GRB 010921: The afterglow of HETE #1761
  40. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  41. GRB010923 as seen by BeppoSAX GRBM
  42. GRB010928(=H1770): Localization of a Long GRB by HETE
  43. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  44. H1761: A Bright GRB Detected by HETE
  45. GRB000926, Host Galaxy Observations
  46. GRB001109, Host Galaxy Spectroscopic Observations
  47. Probable SGR or Short Duration GRB Detected by HETE
  48. GRB000926 Host Galaxy Observations
  49. BeppoSAX/GRBM detection of GRB 010801
  50. GCN and HETE status
  51. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  52. BeppoSAX/GRBM detection of GRB010728
  53. GRB 010222 - WHT BVRI images
  54. SGR1900+14 burst seen by HETE: BeppoSAX data
  55. SGR1900+14: High Fluence Burst Localized by HETE
  56. GRB010629: A Burst Localized by HETE
  57. SGR1900+14: Second Burst Localized by HETE
  58. SGR1900+14: A Burst Localized by HETE
  59. SGR1806-20: A Second, Intense Burst Localized by HETE
  60. GRB 00630: Host Galaxy
  61. SGR1806-20: Localization by HETE
  62. HETE Fully-Automated GCN Notices
  63. GRB010518: a faint BeppoSAX detection
  64. GRB000418: HST/STIS Second-epoch Observations
  65. X-ray precursors to the large flare from SGR 1900+14
  66. GRB010214, optical observations
  67. GRB010427, Gamma Ray Observations
  68. SGR 1900+14: No evidence of extended X-ray emission
  69. SGR 1900+14 : RXTE observations
  70. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  71. Millimeter observation of SGR 1900+14
  72. SGR 1900+14: Detection of extended X-ray emission
  73. SGR 1900+14, Chandra observations
  74. SGR1900+14, I-band observations
  75. Giant flare from SGR1900+14
  76. GRB010412: Optical observations
  77. GRB010412: Optical observations
  78. GRB010412: BeppoSAX GRBM and WFC observations
  79. BeppoSAX GRB ALERT: GRB010412
  80. GRB010324, revised field photometry
  81. GRB 980326: Late-time HST/STIS observations
  82. GRB010222, CXO X-ray observations
  83. GRB 010326B: Optical observations
  84. GRB010326B: Localization by HETE (2nd GRB for this date)
  85. GRB010326: Refined Localization by HETE
  86. GRB010326: Localization by HETE
  87. GRB010222, late-time optical observation
  88. GRB 010222 - HEGRA GeV/TeV Observations
  89. GRB010222: Chandra X-ray Observatory Observation
  90. GRB010222: Sub-millimeter vanishing act
  91. GRB010220 optical obsercations
  92. GRB 010222: High-Resolution Keck Spectroscopy
  93. GRB 010214, I-band data
  94. GRB 010222
  95. GRB 010222 HST/Chandra TOO
  96. GRB 010222
  97. GRB010222 further R-band photometry
  98. GRB010222 Optical observations
  99. GRB 010222: Keck Spectroscopy
  100. GRB010222 further R-band photometry

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