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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

26176 results found.

  1. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  2. GRB010921, negative optical observations
  3. GRB010921 field photometry
  4. H1761: A Bright GRB Detected by HETE
  5. GRB000926, Host Galaxy Observations
  6. GRB001109, Host Galaxy Spectroscopic Observations
  7. Probable SGR or Short Duration GRB Detected by HETE
  8. GCN and HETE status
  9. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  10. GRB 010222 - WHT BVRI images
  11. SGR1900+14 burst seen by HETE: BeppoSAX data
  12. GRB 010629 Optical Observations
  13. SGR1900+14: High Fluence Burst Localized by HETE
  14. GRB010629, optical observations
  15. GRB010629: A Burst Localized by HETE
  16. SGR1900+14: Second Burst Localized by HETE
  17. SGR1900+14: A Burst Localized by HETE
  18. SGR1806-20: A Second, Intense Burst Localized by HETE
  19. SGR1806-20: Localization by HETE
  20. HETE Fully-Automated GCN Notices
  21. GRB000301C: Late-time HST/STIS observation
  22. GRB010518: a faint BeppoSAX detection
  23. GRB000418: HST/STIS Second-epoch Observations
  24. X-ray precursors to the large flare from SGR 1900+14
  25. GRB010427, Gamma Ray Observations
  26. SGR 1900+14: No evidence of extended X-ray emission
  27. SGR 1900+14 : RXTE observations
  28. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  29. SGR 1900+14: Correction to GCN 1049
  30. GRB 010222 /corrections to VBT data
  31. Millimeter observation of SGR 1900+14
  32. SGR 1900+14: Detection of extended X-ray emission
  33. SGR 1900+14, Chandra observations
  34. SGR1900+14, I-band observations
  35. GRB010412, field photometry
  36. Giant flare from SGR1900+14
  37. GRB 010326b Optical Observations
  38. GRB010412: BeppoSAX GRBM and WFC observations
  39. GRB010324, revised field photometry
  40. REVISED LOCATION OF GRB010326A
  41. GRB 980326: Late-time HST/STIS observations
  42. GRB010324, field photometry
  43. GRB010326B, field photometry
  44. GRB010326, field photometry
  45. GRB010220, field photometry
  46. Further Optical Observations of GRB 010324
  47. GRB010222, CXO X-ray observations
  48. GRB010324, optical observations
  49. GRB010326B: Localization by HETE (2nd GRB for this date)
  50. GRB 010326 optical observations
  51. GRB010326: Refined Localization by HETE
  52. GRB010326: Localization by HETE
  53. Optical Observations of GRB 010324
  54. GRB010222, late-time optical observation
  55. Support extension to the BeppoSAX mission
  56. GRB 010222 - HEGRA GeV/TeV Observations
  57. GRB010222: Chandra X-ray Observatory Observation
  58. GRB010222: Sub-millimeter vanishing act
  59. GRB010222 - Optical observation
  60. GRB 010222, Optical Observations
  61. GRB010222 - Optical observation
  62. GRB 010222: High-Resolution Keck Spectroscopy
  63. GRB 010214, I-band data
  64. GRB 010222
  65. GRB010222 further R-band photometry
  66. GRB010222: R-band data
  67. GRB 010222: Keck Spectroscopy
  68. GRB010214, field photometry
  69. GRB010222, field photometry
  70. GRB010222 further R-band photometry
  71. GRB010222, possible increase of optical decay slope
  72. GRB 010222 Kyoto optical observation
  73. GRB010222 R-BAND OBSERVATION
  74. GRB010214 follow-up from Hanle
  75. GRB 010222: Near-IR Observations
  76. GRB 010222: Optical Observations
  77. GRB010222: Optical decay slope
  78. GRB 010214, Optical Observations
  79. GRB010222, radio observations
  80. GRB010222, optical observations
  81. GRB010222: BeppoSAX/NFI Observations
  82. GRB010214B,Gamma Ray Observations
  83. GRB 010220, simultaneous optical observations
  84. GRB010220: BeppoSAX WFC and GRBM preliminary data
  85. GRB010214, candidate optical afterglow
  86. GRB010214, optical observations
  87. GRB010214: BeppoSAX WFC and GRBM preliminary data
  88. GRB 010214: X-Ray afterglow
  89. GRB 010214 optical observation
  90. GRB010213, Radio Observations
  91. J-Band Observation of GRB 010214.
  92. GRB010213, Near-IR observations
  93. Possible InfraRed Transient of GRB 010214.
  94. GRB 010214, optical observations
  95. GRB010213 detected by HETE
  96. IPN Status Report
  97. HETE Status
  98. IPN/RXTE TRIANGULATION OF GRB010126
  99. GRB010126 Optical Observations
  100. IPN TRIANGULATION OF GRB010126

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