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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"

42572 results found.

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

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