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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"

32484 results found.

  1. GRB000926, Host Galaxy Observations
  2. GRB001109, Host Galaxy Spectroscopic Observations
  3. Probable SGR or Short Duration GRB Detected by HETE
  4. GCN and HETE status
  5. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  6. GRB 010222 - WHT BVRI images
  7. SGR1900+14 burst seen by HETE: BeppoSAX data
  8. GRB 010629 Optical Observations
  9. GRB010629: Optical Observations
  10. SGR1900+14: High Fluence Burst Localized by HETE
  11. GRB010629, optical observations
  12. IPN triangulation of GRB010629
  13. SGR1900+14: Second Burst Localized by HETE
  14. SGR1900+14: A Burst Localized by HETE
  15. Possible burst from SGR1806-20
  16. SGR1806-20: A Second, Intense Burst Localized by HETE
  17. IPN triangulation of GRB010613
  18. IPN triangulation of GRB010612
  19. IPN triangulation of GRB010612
  20. HETE Fully-Automated GCN Notices
  21. GRB000301C: Late-time HST/STIS observation
  22. GRB000418: HST/STIS Second-epoch Observations
  23. X-ray precursors to the large flare from SGR 1900+14
  24. GRB010214, optical observations
  25. SGR 1900+14: No evidence of extended X-ray emission
  26. SGR 1900+14 : RXTE observations
  27. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  28. SGR1900+14 - correction
  29. SGR1900+14
  30. SGR 1900+14: Correction to GCN 1049
  31. Millimeter observation of SGR 1900+14
  32. SGR 1900+14: Detection of extended X-ray emission
  33. Chandra Observations of SGR 1900+14
  34. SGR 1900+14, Chandra observations
  35. Chandra Observations of SGR 1900+14
  36. Possible precursor to the SGR1900+14 giant burst
  37. SGR1900+14, I-band observations
  38. IPN Triangulation of the Giant Flare from SGR1900+14
  39. GRB 010326b Optical Observations
  40. GRB010412: Optical observations
  41. GRB010412: Optical observations
  42. IPN Triangulation of GRB010412
  43. GRB Observation Report
  44. REVISED LOCATION OF GRB010326A
  45. GRB 980326: Late-time HST/STIS observations
  46. GRB010324, field photometry
  47. GRB010326B, field photometry
  48. GRB010326, field photometry
  49. GRB010220, field photometry
  50. Further Optical Observations of GRB 010324
  51. GRB010222, CXO X-ray observations
  52. GRB010324: BeppoSAX/GRBM data
  53. GRB010324, optical observations
  54. Duration, ECT, peak flux and fluence of GRB010324
  55. Optical Observations of GRB 010324
  56. IPN TRIANGULATION OF GRB010324
  57. GRB990705, VLT-FORS1 observations of the host galaxy
  58. GRB010222, late-time optical observation
  59. GRB 010222 - HEGRA GeV/TeV Observations
  60. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  61. GRB010222: Chandra X-ray Observatory Observation
  62. GRB010222: Sub-millimeter vanishing act
  63. GRB010222 - Optical observation
  64. GRB 010222, Optical Observations
  65. GRB010220 optical obsercations
  66. GRB010222 - Optical observation
  67. GRB 010222: High-Resolution Keck Spectroscopy
  68. GRB010222: Optical observation and decay
  69. GRB 010214, I-band data
  70. Sub-millimeter Excess/GRB 010222
  71. GRB 010222
  72. GRB 010222 HST/Chandra TOO
  73. GRB010222 further R-band photometry
  74. GRB010222: R-band data
  75. GRB010222 Optical observations
  76. GRB 010222: Keck Spectroscopy
  77. GRB010222 further R-band photometry
  78. GRB010222, possible increase of optical decay slope
  79. GRB010222: fading behavior
  80. GRB 010222 BV optical observations
  81. GRB010222 R-BAND OBSERVATION
  82. GRB 010220: Near-IR Observations
  83. GRB010214 follow-up from Hanle
  84. GRB 010222: Near-IR Observations
  85. GRB 010222: Optical Observations
  86. GRB 010222, Decay Slope Confirmed
  87. GRB010222: Another absorption line system
  88. GRB010222: Optical decay slope
  89. GRB 010214, Optical Observations
  90. GRB010222: Sub-millimeter detection
  91. GRB010222: R-band fading behavior
  92. GRB010222: Optical Observations
  93. GRB010222, radio observations
  94. GRB010222, optical observations
  95. GRB010222: BeppoSAX/NFI Observations
  96. Redshift of the Optical Transient of GRB010222
  97. GRB010222: possible optical counterpart
  98. GRB010222
  99. GRB010222: BeppoSAX refined position
  100. ALERT: GRB010222: the brightest GRB observed by BeppoSAX

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