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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"

37943 results found.

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

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