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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"

36148 results found.

  1. BeppoSAX/GRBM detection of GRB 010801
  2. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  3. GRB 010222 - WHT BVRI images
  4. GRB 010629 Optical Observations
  5. GRB010629: Optical Observations
  6. GRB010629, optical observations
  7. IPN triangulation of GRB010629
  8. GRB010629: A Burst Localized by HETE
  9. Possible burst from SGR1806-20
  10. IPN detection of SGR1900+14
  11. GRB 00630: Host Galaxy
  12. IPN triangulation of GRB010613
  13. IPN triangulation of GRB010612
  14. HETE Fully-Automated GCN Notices
  15. GRB000301C: Late-time HST/STIS observation
  16. GRB010518: a faint BeppoSAX detection
  17. GRB000418: HST/STIS Second-epoch Observations
  18. GRB010427, Gamma Ray Observations
  19. SGR1900+14
  20. GRB 010222 /corrections to VBT data
  21. Possible precursor to the SGR1900+14 giant burst
  22. IPN Triangulation of the Giant Flare from SGR1900+14
  23. GRB010412, field photometry
  24. GRB 010326b Optical Observations
  25. GRB010412: Optical observations
  26. GRB010412: Optical observations
  27. IPN Triangulation of GRB010412
  28. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  29. BeppoSAX GRB ALERT: GRB010412
  30. GRB Observation Report
  31. GRB010324, revised field photometry
  32. REVISED LOCATION OF GRB010326A
  33. GRB 980326: Late-time HST/STIS observations
  34. GRB010324, field photometry
  35. GRB010326B, field photometry
  36. GRB010326, field photometry
  37. GRB010220, field photometry
  38. Further Optical Observations of GRB 010324
  39. GRB 010326A: Further optical observations
  40. GRB010324: BeppoSAX/GRBM data
  41. GRB 010326B: Optical observations
  42. GRB010324, optical observations
  43. GRB010326B: Localization by HETE (2nd GRB for this date)
  44. GRB 010326: Optical observations
  45. GRB 010326 optical observations
  46. GRB010326: Refined Localization by HETE
  47. GRB010326: Localization by HETE
  48. Duration, ECT, peak flux and fluence of GRB010324
  49. Optical Observations of GRB 010324
  50. IPN TRIANGULATION OF GRB010324
  51. GRB990705, VLT-FORS1 observations of the host galaxy
  52. GRB010222, late-time optical observation
  53. Support extension to the BeppoSAX mission
  54. GRB 010222 - HEGRA GeV/TeV Observations
  55. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  56. GRB010222: Chandra X-ray Observatory Observation
  57. GRB010222: Sub-millimeter vanishing act
  58. GRB 010222, Optical Observations
  59. GRB 010222: High-Resolution Keck Spectroscopy
  60. GRB 010214, I-band data
  61. Sub-millimeter Excess/GRB 010222
  62. GRB 010222
  63. GRB 010222 HST/Chandra TOO
  64. GRB 010222
  65. GRB010222 further R-band photometry
  66. GRB010222: R-band data
  67. GRB010222 Optical observations
  68. GRB 010222: Keck Spectroscopy
  69. GRB010214, field photometry
  70. GRB010222, field photometry
  71. GRB010222 further R-band photometry
  72. GRB010222, possible increase of optical decay slope
  73. GRB 010222 Kyoto optical observation
  74. GRB010222: fading behavior
  75. GRB 010222 BV optical observations
  76. GRB 010220: Near-IR Observations
  77. GRB010214 follow-up from Hanle
  78. GRB 010222: Near-IR Observations
  79. GRB 010222: Optical Observations
  80. GRB 010222, Decay Slope Confirmed
  81. GRB010222: Another absorption line system
  82. GRB010222: Optical decay slope
  83. GRB 010214, Optical Observations
  84. GRB010222: Sub-millimeter detection
  85. GRB010222: R-band fading behavior
  86. GRB010222: Optical Observations
  87. GRB010222, optical observations
  88. GRB010222: BeppoSAX/NFI Observations
  89. Redshift of the Optical Transient of GRB010222
  90. GRB010214B,Gamma Ray Observations
  91. GRB010222
  92. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  93. GRB 010220, simultaneous optical observations
  94. GRB010220: BeppoSAX WFC and GRBM preliminary data
  95. BeppoSAX ALERT: GRB010220
  96. GRB010214: BeppoSAX WFC and GRBM preliminary data
  97. GRB 010214: X-Ray afterglow
  98. GRB 010214, Optical Observations
  99. GRB 010214 optical observation
  100. GRB010213 Optical Observation

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