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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"

36145 results found.

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

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