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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"

22194 results found.

  1. GRB011130 (=XRF011130), Optical Observations
  2. XRF011130: NEAT Optical Observations
  3. GRB 011121
  4. GRB 011121: J-band observations
  5. GRB 011121: NIR observations, host galaxy?
  6. GRB010921 - Milagro GeV/TeV Observations
  7. GRB 011121: HST Scheduled
  8. GRB011121: fainter still
  9. GRB011121: UBRI Observations
  10. GRB011121
  11. GRB 011121: Radio Observations
  12. GRB011121: continued decay
  13. GRB 011121: Detection of Bright IR Counterpart
  14. GRB011121: possible redshift, continued decay
  15. GRB011121: fading behavior
  16. GRB011121: possible optical counterpart
  17. GRB 011030: TNG K-band observation
  18. XRF011030: J and K band observations
  19. XRF011030: Chandra Observations
  20. GRB 011030: K-band observations
  21. GRB011030: Z-band observations
  22. GRB 011030 R band observations
  23. The X-ray Flash 011030 ('GRB 011030')
  24. Non-triggered burst 011030 ("GRB 011030")
  25. The Radio Afterglow from the X-ray Rich GRB 011030
  26. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  27. GRB 970828: HST Observations of the Host Galaxy
  28. GRB 970828: HST Observations of the Host Galaxy
  29. GRB010921, optical observation
  30. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  31. GRB011019: Subaru Optical Observations
  32. GRB 011030 I-band Observations
  33. GRB 011030 K-band Observations
  34. GRB010921, optical observations
  35. GRB 011030, WSRT radio observations
  36. GRB 011030, Radio observations
  37. GRB 011030, R-band observations
  38. GRB 010921: Possible supernova component
  39. GRB011019: NEAT Optical Observations
  40. GRB011019: ROTSE-III optical observations
  41. GRB 010921, I-band observations
  42. GRB011019: Optical observations
  43. GRB011019, optical observations -- correction
  44. GRB011019, optical observations
  45. GRB 010921: The afterglow of HETE #1761
  46. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  47. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  48. GRB010928(=H1770): Localization of a Long GRB by HETE
  49. GRB010921, negative optical observations
  50. GRB010921 Optical Observations
  51. GRB 010921 DPOSS Images Available
  52. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  53. HETE Trigger #1760 (GRB 010920B?): a new optical source
  54. HETE Trigger #1759 (GRB 010920?) optical observations
  55. GRB000926, Host Galaxy Observations
  56. GRB001109, Host Galaxy Spectroscopic Observations
  57. GRB000926 Host Galaxy Observations
  58. GRB 010222: HST observations -- host galaxy and late-time decay
  59. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  60. GRB 010222 - WHT BVRI images
  61. GRB 010629 Optical Observations
  62. GRB010629: Optical Observations
  63. SGR1900+14: High Fluence Burst Localized by HETE
  64. GRB010629, optical observations
  65. GRB010629: A Burst Localized by HETE
  66. SGR1900+14: Second Burst Localized by HETE
  67. SGR1900+14: A Burst Localized by HETE
  68. SGR1806-20: A Second, Intense Burst Localized by HETE
  69. GRB 00630: Host Galaxy
  70. SGR1806-20: Localization by HETE
  71. GRB000418: HST/STIS Second-epoch Observations
  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. GRB 010222 /corrections to VBT data
  77. Millimeter observation of SGR 1900+14
  78. Chandra Observations of SGR 1900+14
  79. SGR 1900+14, Chandra observations
  80. Chandra Observations of SGR 1900+14
  81. SGR1900+14, I-band observations
  82. GRB 010326b Optical Observations
  83. GRB010412: Optical observations
  84. GRB010412: Optical observations
  85. GRB010412: BeppoSAX GRBM and WFC observations
  86. GRB Observation Report
  87. GRB 980326: Late-time HST/STIS observations
  88. GRB010326B, field photometry
  89. Further Optical Observations of GRB 010324
  90. GRB010222, CXO X-ray observations
  91. GRB 010326A: Further optical observations
  92. GRB 010326B: Optical observations
  93. GRB010324, optical observations
  94. GRB010326B: Localization by HETE (2nd GRB for this date)
  95. GRB 010326: Optical observations
  96. GRB 010326 optical observations
  97. GRB010326: Refined Localization by HETE
  98. GRB010326: Localization by HETE
  99. Optical Observations of GRB 010324
  100. IPN TRIANGULATION OF GRB010324

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