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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"

17643 results found.

  1. BeppoSAX/GRBM detection of GRB010728
  2. GRB 010222 - WHT BVRI images
  3. GRB 010629 Optical Observations
  4. SGR1900+14: High Fluence Burst Localized by HETE
  5. GRB010629, optical observations
  6. GRB010629: A Burst Localized by HETE
  7. SGR1900+14: Second Burst Localized by HETE
  8. SGR1900+14: A Burst Localized by HETE
  9. SGR1806-20: A Second, Intense Burst Localized by HETE
  10. SGR1806-20: Localization by HETE
  11. HETE Fully-Automated GCN Notices
  12. GRB000301C: Late-time HST/STIS observation
  13. GRB010518: a faint BeppoSAX detection
  14. GRB000418: HST/STIS Second-epoch Observations
  15. X-ray precursors to the large flare from SGR 1900+14
  16. GRB010427, Gamma Ray Observations
  17. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  18. Millimeter observation of SGR 1900+14
  19. SGR1900+14, I-band observations
  20. GRB010412, field photometry
  21. Giant flare from SGR1900+14
  22. GRB 010326b Optical Observations
  23. GRB010412: BeppoSAX GRBM and WFC observations
  24. GRB010324, revised field photometry
  25. GRB 980326: Late-time HST/STIS observations
  26. GRB010324, field photometry
  27. GRB010326B, field photometry
  28. GRB010326, field photometry
  29. GRB010220, field photometry
  30. Further Optical Observations of GRB 010324
  31. GRB010222, CXO X-ray observations
  32. GRB010324: BeppoSAX/GRBM data
  33. GRB010324, optical observations
  34. GRB010326B: Localization by HETE (2nd GRB for this date)
  35. GRB 010326 optical observations
  36. GRB010326: Refined Localization by HETE
  37. GRB010326: Localization by HETE
  38. Optical Observations of GRB 010324
  39. IPN TRIANGULATION OF GRB010324
  40. GRB010222, late-time optical observation
  41. Support extension to the BeppoSAX mission
  42. GRB 010222, Optical Observations
  43. GRB010220 optical obsercations
  44. GRB010222 - Optical observation
  45. GRB010222 further R-band photometry
  46. GRB 010222: Keck Spectroscopy
  47. GRB010214, field photometry
  48. GRB010222, field photometry
  49. GRB010222 further R-band photometry
  50. GRB 010222 Kyoto optical observation
  51. GRB010222 R-BAND OBSERVATION
  52. GRB010214 follow-up from Hanle
  53. GRB 010222: Near-IR Observations
  54. GRB 010222: Optical Observations
  55. GRB 010222, Decay Slope Confirmed
  56. GRB010222, radio observations
  57. GRB010222, optical observations
  58. GRB 010220, simultaneous optical observations
  59. GRB010220: BeppoSAX WFC and GRBM preliminary data
  60. GRB010214, optical observations
  61. GRB010214: BeppoSAX WFC and GRBM preliminary data
  62. GRB 010214: X-Ray afterglow
  63. GRB 010214 optical observation
  64. J-Band Observation of GRB 010214.
  65. GRB010214, optical observations
  66. GRB010213, optical observations
  67. GRB010213, Near-IR observations
  68. Possible InfraRed Transient of GRB 010214.
  69. GRB010214 Optical Observation
  70. GRB010213 detected by HETE
  71. HETE Status
  72. Optical Observations of GRB 001018 at Keck
  73. Optical observations of GRB 001018 with JCAM
  74. IPN TRIANGULATION OF GRB010109
  75. IPN triangulation of GRB010104
  76. IPN triangulation of GRB010103
  77. IPN triangulation of GRB001219
  78. GRB 001212 Optical Observation
  79. GRB 001212 Optical Observation
  80. GRB001120, optical observations
  81. GRB 001109: deep JHK upper limits
  82. GRB 001109 X-ray afterglow with BeppoSAX
  83. CORRECTION to XMM-Newton observation of GRB001025
  84. GRB001109, Radio observations
  85. GRB001105 BVRI field photometry correction
  86. GRB001105, BVRI field photometry
  87. GRB 001025B, Optical obervations
  88. GRB 991208: HST Imaging of the Host Galaxy
  89. GRB 001025B, I-band observations
  90. GRB 001025A, optical observation
  91. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  92. GRB001007: Optical observations
  93. GRB001007, Radio observations
  94. IPN TRIANGULATION OF GRB001020
  95. CORRECTION TO PEAK FLUX OF GRB001018
  96. IPN TRIANGULATION OF GRB 001017
  97. V,R,I band observations of GRB000926
  98. GRB000926 - Amateur Optical Observations
  99. CONCAM null result on GRB001005
  100. GRB000926 - Optical observations

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