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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"

35946 results found.

  1. GRB000926 Host Galaxy Observations
  2. GRB 010222: HST observations -- host galaxy and late-time decay
  3. BeppoSAX/GRBM detection of GRB 010801
  4. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  5. GRB 010222 - WHT BVRI images
  6. GRB 010629 Optical Observations
  7. GRB010629: Optical Observations
  8. GRB010629, optical observations
  9. IPN triangulation of GRB010629
  10. GRB010629: A Burst Localized by HETE
  11. Possible burst from SGR1806-20
  12. IPN detection of SGR1900+14
  13. GRB 00630: Host Galaxy
  14. IPN triangulation of GRB010613
  15. IPN triangulation of GRB010612
  16. HETE Fully-Automated GCN Notices
  17. GRB000301C: Late-time HST/STIS observation
  18. GRB010518: a faint BeppoSAX detection
  19. GRB000418: HST/STIS Second-epoch Observations
  20. GRB010427, Gamma Ray Observations
  21. SGR1900+14
  22. GRB 010222 /corrections to VBT data
  23. Possible precursor to the SGR1900+14 giant burst
  24. IPN Triangulation of the Giant Flare from SGR1900+14
  25. GRB010412, field photometry
  26. GRB 010326b Optical Observations
  27. GRB010412: Optical observations
  28. GRB010412: Optical observations
  29. IPN Triangulation of GRB010412
  30. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  31. BeppoSAX GRB ALERT: GRB010412
  32. GRB Observation Report
  33. GRB010324, revised field photometry
  34. REVISED LOCATION OF GRB010326A
  35. GRB 980326: Late-time HST/STIS observations
  36. GRB010324, field photometry
  37. GRB010326B, field photometry
  38. GRB010326, field photometry
  39. GRB010220, field photometry
  40. Further Optical Observations of GRB 010324
  41. GRB 010326A: Further optical observations
  42. GRB010324: BeppoSAX/GRBM data
  43. GRB 010326B: Optical observations
  44. GRB010324, optical observations
  45. GRB010326B: Localization by HETE (2nd GRB for this date)
  46. GRB 010326: Optical observations
  47. GRB 010326 optical observations
  48. GRB010326: Refined Localization by HETE
  49. GRB010326: Localization by HETE
  50. Duration, ECT, peak flux and fluence of GRB010324
  51. Optical Observations of GRB 010324
  52. IPN TRIANGULATION OF GRB010324
  53. GRB990705, VLT-FORS1 observations of the host galaxy
  54. GRB010222, late-time optical observation
  55. Support extension to the BeppoSAX mission
  56. GRB 010222 - HEGRA GeV/TeV Observations
  57. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  58. GRB010222: Chandra X-ray Observatory Observation
  59. GRB010222: Sub-millimeter vanishing act
  60. GRB 010222, Optical Observations
  61. GRB 010222: High-Resolution Keck Spectroscopy
  62. GRB 010214, I-band data
  63. Sub-millimeter Excess/GRB 010222
  64. GRB 010222
  65. GRB 010222 HST/Chandra TOO
  66. GRB 010222
  67. GRB010222 further R-band photometry
  68. GRB010222: R-band data
  69. GRB010222 Optical observations
  70. GRB 010222: Keck Spectroscopy
  71. GRB010214, field photometry
  72. GRB010222, field photometry
  73. GRB010222 further R-band photometry
  74. GRB010222, possible increase of optical decay slope
  75. GRB 010222 Kyoto optical observation
  76. GRB010222: fading behavior
  77. GRB 010222 BV optical observations
  78. GRB 010220: Near-IR Observations
  79. GRB010214 follow-up from Hanle
  80. GRB 010222: Near-IR Observations
  81. GRB 010222: Optical Observations
  82. GRB 010222, Decay Slope Confirmed
  83. GRB010222: Another absorption line system
  84. GRB010222: Optical decay slope
  85. GRB 010214, Optical Observations
  86. GRB010222: Sub-millimeter detection
  87. GRB010222: R-band fading behavior
  88. GRB010222: Optical Observations
  89. GRB010222, optical observations
  90. GRB010222: BeppoSAX/NFI Observations
  91. Redshift of the Optical Transient of GRB010222
  92. GRB010214B,Gamma Ray Observations
  93. GRB010222
  94. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  95. GRB 010220, simultaneous optical observations
  96. GRB010220: BeppoSAX WFC and GRBM preliminary data
  97. BeppoSAX ALERT: GRB010220
  98. GRB010214: BeppoSAX WFC and GRBM preliminary data
  99. GRB 010214: X-Ray afterglow
  100. GRB 010214, Optical Observations

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