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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"

38356 results found.

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