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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"

45515 results found.

  1. GRB010921, optical observation
  2. GRB 011019 optical observation
  3. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  4. GRB011019: Subaru Optical Observations
  5. GRB 011030 I-band Observations
  6. GRB 011030 K-band Observations
  7. GRB010921, optical observations
  8. GRB 011030, WSRT radio observations
  9. GRB011030 - further refinement WFC position
  10. GRB 011030, Radio observations
  11. GRB011030: radio search
  12. GRB 011030, R-band observations
  13. X-ray rich GRB011030: BeppoSAX refined positions
  14. BeppoSAX ALERT: Possible X-ray rich GRB011030
  15. GRB 010921: Possible supernova component
  16. GRB011019: NEAT Optical Observations
  17. GRB011019: ROTSE-III optical observations
  18. GRB010921, optical observation at early time
  19. GRB 010921, I-band observations
  20. GRB011019: Optical observations
  21. GRB011019, optical observations
  22. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  23. GRB010921: Spectroscopy of the Host Galaxy
  24. GRB 010921: The afterglow of HETE #1761
  25. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  26. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  27. GRB010923 as seen by BeppoSAX GRBM
  28. GRB010928(=H1770): Localization of a Long GRB by HETE
  29. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  30. GRB010921, negative optical observations
  31. GRB010921 field photometry
  32. GRB010921 Optical Observations
  33. GRB 010921 DPOSS Images Available
  34. IPN triangulation of GRB010921 (=H1761)
  35. H1761: A Bright GRB Detected by HETE
  36. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  37. HETE Trigger #1760 (GRB 010920B?): a new optical source
  38. HETE Trigger #1759 (GRB 010920?) optical observations
  39. GRB001109, Host Galaxy Astrometry
  40. GRB000926, Host Galaxy Observations
  41. GRB001109, Host Galaxy Spectroscopic Observations
  42. Probable SGR or Short Duration GRB Detected by HETE
  43. GRB000926 Host Galaxy Observations
  44. GRB 010222: HST observations -- host galaxy and late-time decay
  45. BeppoSAX/GRBM detection of GRB 010801
  46. GCN and HETE status
  47. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  48. BeppoSAX/GRBM detection of GRB010728
  49. GRB 010222 - WHT BVRI images
  50. SGR1900+14 burst seen by HETE: BeppoSAX data
  51. GRB 010629 Optical Observations
  52. GRB010629: Optical Observations
  53. SGR1900+14: High Fluence Burst Localized by HETE
  54. GRB010629, optical observations
  55. IPN triangulation of GRB010629
  56. GRB010629: A Burst Localized by HETE
  57. SGR1900+14: Second Burst Localized by HETE
  58. SGR1900+14: A Burst Localized by HETE
  59. Possible burst from SGR1806-20
  60. IPN detection of SGR1900+14
  61. SGR1806-20: A Second, Intense Burst Localized by HETE
  62. GRB 00630: Host Galaxy
  63. SGR1806-20: Localization by HETE
  64. IPN triangulation of GRB010613
  65. IPN triangulation of GRB010612
  66. IPN triangulation of GRB010612
  67. HETE Fully-Automated GCN Notices
  68. GRB000301C: Late-time HST/STIS observation
  69. GRB010518: a faint BeppoSAX detection
  70. GRB000418: HST/STIS Second-epoch Observations
  71. X-ray precursors to the large flare from SGR 1900+14
  72. GRB010214, optical observations
  73. GRB010427, Gamma Ray Observations
  74. SGR 1900+14: No evidence of extended X-ray emission
  75. SGR 1900+14 : RXTE observations
  76. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  77. SGR1900+14
  78. SGR 1900+14: Correction to GCN 1049
  79. GRB 010222 /corrections to VBT data
  80. Millimeter observation of SGR 1900+14
  81. SGR 1900+14: Detection of extended X-ray emission
  82. Chandra Observations of SGR 1900+14
  83. SGR 1900+14, Chandra observations
  84. Chandra Observations of SGR 1900+14
  85. Possible precursor to the SGR1900+14 giant burst
  86. SGR1900+14, I-band observations
  87. IPN Triangulation of the Giant Flare from SGR1900+14
  88. GRB010412, field photometry
  89. Giant flare from SGR1900+14
  90. GRB 010326b Optical Observations
  91. GRB010412: Optical observations
  92. GRB010412: Optical observations
  93. GRB010412: BeppoSAX GRBM and WFC observations
  94. IPN Triangulation of GRB010412
  95. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  96. BeppoSAX GRB ALERT: GRB010412
  97. GRB Observation Report
  98. GRB010324, revised field photometry
  99. REVISED LOCATION OF GRB010326A
  100. GRB 980326: Late-time HST/STIS observations

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