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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"
  1. GRB010324, field photometry
  2. GRB010326B, field photometry
  3. GRB010326, field photometry
  4. GRB010220, field photometry
  5. Further Optical Observations of GRB 010324
  6. GRB010222, CXO X-ray observations
  7. GRB 010326A: Further optical observations
  8. GRB010324: BeppoSAX/GRBM data
  9. GRB 010326B: Optical observations
  10. GRB010324, optical observations
  11. GRB010326B: Localization by HETE (2nd GRB for this date)
  12. GRB 010326: Optical observations
  13. GRB 010326 optical observations
  14. GRB010326: Refined Localization by HETE
  15. GRB010326: Localization by HETE
  16. Duration, ECT, peak flux and fluence of GRB010324
  17. Optical Observations of GRB 010324
  18. IPN TRIANGULATION OF GRB010324
  19. GRB990705, VLT-FORS1 observations of the host galaxy
  20. GRB010222, late-time optical observation
  21. Support extension to the BeppoSAX mission
  22. GRB 010222 - HEGRA GeV/TeV Observations
  23. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  24. GRB010222: Chandra X-ray Observatory Observation
  25. GRB010222: Sub-millimeter vanishing act
  26. GRB010222 - Optical observation
  27. GRB 010222, Optical Observations
  28. GRB010220 optical obsercations
  29. GRB010222 - Optical observation
  30. GRB 010222: High-Resolution Keck Spectroscopy
  31. GRB010222: Optical observation and decay
  32. GRB 010214, I-band data
  33. Sub-millimeter Excess/GRB 010222
  34. GRB 010222
  35. GRB 010222 HST/Chandra TOO
  36. GRB 010222
  37. GRB010222 further R-band photometry
  38. GRB010222: R-band data
  39. GRB010222 Optical observations
  40. GRB 010222: Keck Spectroscopy
  41. GRB010214, field photometry
  42. GRB010222, field photometry
  43. GRB010222 further R-band photometry
  44. GRB010222, possible increase of optical decay slope
  45. GRB 010222 Kyoto optical observation
  46. GRB010222: fading behavior
  47. GRB 010222 BV optical observations
  48. GRB010220, Optical Observations
  49. GRB010222 R-BAND OBSERVATION
  50. GRB 010220: Near-IR Observations
  51. GRB010214 follow-up from Hanle
  52. GRB 010222: Near-IR Observations
  53. GRB 010222: Optical Observations
  54. GRB 010222, Decay Slope Confirmed
  55. GRB010222: Another absorption line system
  56. GRB010222: Optical decay slope
  57. GRB 010214, Optical Observations
  58. GRB010222: Sub-millimeter detection
  59. GRB010222: R-band fading behavior
  60. GRB010222: Optical Observations
  61. GRB010222, radio observations
  62. GRB010222, optical observations
  63. GRB010222: BeppoSAX/NFI Observations
  64. Redshift of the Optical Transient of GRB010222
  65. GRB010214B,Gamma Ray Observations
  66. GRB010222: possible optical counterpart
  67. GRB010222
  68. GRB010222
  69. GRB010222: BeppoSAX refined position
  70. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  71. GRB010220, Radio and Optical Observations
  72. GRB 010220, simultaneous optical observations
  73. GRB010220: BeppoSAX WFC and GRBM preliminary data
  74. GRB010214, candidate optical afterglow
  75. GRB010214, optical observations
  76. BeppoSAX GRB010220: refined position
  77. BeppoSAX ALERT: GRB010220
  78. GRB010214: BeppoSAX WFC and GRBM preliminary data
  79. GRB 010214: X-Ray afterglow
  80. GRB 010214, Optical Observations
  81. GRB 010214 optical observation
  82. GRB010213, Radio Observations
  83. GRB010213 Optical Observation
  84. GRB010213, Radio Observations
  85. J-Band Observation of GRB 010214.
  86. GRB010214, Radio Observations
  87. GRB010214, optical observations
  88. GRB010213, optical observations
  89. GRB010213, Near-IR observations
  90. Possible InfraRed Transient of GRB 010214.
  91. GRB010214 Optical Observation
  92. GRB010214: BeppoSAX/NFI Observations
  93. GRB010213 (HETE) TAROT observations
  94. GRB 010214, optical observations
  95. GRB010213 detected by HETE
  96. GRB010214 refined WFC position
  97. BeppoSAX ALERT: GRB010214
  98. IPN Status Report
  99. HETE Status
  100. GRB010126 opt. obs.

Advanced

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