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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"

42203 results found.

  1. GRB010324, optical observations
  2. GRB010326B: Localization by HETE (2nd GRB for this date)
  3. GRB 010326: Optical observations
  4. GRB 010326 optical observations
  5. GRB010326: Refined Localization by HETE
  6. GRB010326: Localization by HETE
  7. Duration, ECT, peak flux and fluence of GRB010324
  8. Optical Observations of GRB 010324
  9. GRB990705, VLT-FORS1 observations of the host galaxy
  10. GRB010222, late-time optical observation
  11. Support extension to the BeppoSAX mission
  12. GRB 010222 - HEGRA GeV/TeV Observations
  13. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  14. GRB010222: Chandra X-ray Observatory Observation
  15. GRB010222: Sub-millimeter vanishing act
  16. GRB010222 - Optical observation
  17. GRB 010222, Optical Observations
  18. GRB010220 optical obsercations
  19. GRB010222 - Optical observation
  20. GRB 010222: High-Resolution Keck Spectroscopy
  21. GRB010222: Optical observation and decay
  22. GRB 010214, I-band data
  23. Sub-millimeter Excess/GRB 010222
  24. GRB 010222
  25. GRB 010222 HST/Chandra TOO
  26. GRB 010222
  27. GRB010222 further R-band photometry
  28. GRB010222: R-band data
  29. GRB010222 Optical observations
  30. GRB 010222: Keck Spectroscopy
  31. GRB010214, field photometry
  32. GRB010222, field photometry
  33. GRB010222 further R-band photometry
  34. GRB010222, possible increase of optical decay slope
  35. GRB 010222 Kyoto optical observation
  36. GRB010222: fading behavior
  37. GRB 010222 BV optical observations
  38. GRB010220, Optical Observations
  39. GRB010222 R-BAND OBSERVATION
  40. GRB 010220: Near-IR Observations
  41. GRB010214 follow-up from Hanle
  42. GRB 010222: Near-IR Observations
  43. GRB 010222: Optical Observations
  44. GRB 010222, Decay Slope Confirmed
  45. GRB010222: Another absorption line system
  46. GRB010222: Optical decay slope
  47. GRB 010214, Optical Observations
  48. GRB010222: Sub-millimeter detection
  49. GRB010222: R-band fading behavior
  50. GRB010222: Optical Observations
  51. GRB010222, radio observations
  52. GRB010222, optical observations
  53. GRB010222: BeppoSAX/NFI Observations
  54. Redshift of the Optical Transient of GRB010222
  55. GRB010222: possible optical counterpart
  56. GRB010222
  57. GRB010220, Radio and Optical Observations
  58. GRB 010220, simultaneous optical observations
  59. GRB010220: BeppoSAX WFC and GRBM preliminary data
  60. GRB010214, candidate optical afterglow
  61. GRB010214, optical observations
  62. GRB010214: BeppoSAX WFC and GRBM preliminary data
  63. GRB 010214: X-Ray afterglow
  64. GRB 010214, Optical Observations
  65. GRB 010214 optical observation
  66. GRB010213, Radio Observations
  67. GRB010213 Optical Observation
  68. GRB010213, Radio Observations
  69. J-Band Observation of GRB 010214.
  70. GRB010214, Radio Observations
  71. GRB010214, optical observations
  72. GRB010213, optical observations
  73. GRB010213, Near-IR observations
  74. Possible InfraRed Transient of GRB 010214.
  75. GRB010214 Optical Observation
  76. GRB010213 (HETE) TAROT observations
  77. GRB 010214, optical observations
  78. GRB010213 detected by HETE
  79. HETE Status
  80. GRB010126 opt. obs.
  81. IPN/RXTE TRIANGULATION OF GRB010126
  82. GRB010126: CONCAM crude optical limits during GRB
  83. GRB010126, TNG R-band observations
  84. GRB010126 Optical Observations
  85. GRB010126 optical observations
  86. GRB010126: Optical observations
  87. IPN/RXTE TRIANGULATION OF GRB010126
  88. GRB 010119, optical observations
  89. GRB010119: Optical observations
  90. Optical Observations of GRB 001018 at Keck
  91. GRB010119, Radio observations
  92. Optical observations of GRB 001018 with JCAM
  93. IPN TRIANGULATION OF GRB010109
  94. IPN TRIANGULATION OF GRB010109
  95. GRB010103, optical observations
  96. IPN triangulation of GRB010103
  97. GRB 001204: Ks observations
  98. H band observation of GRB 001212
  99. IPN triangulation of GRB001219
  100. GRB 001212 Optical Observation

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