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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"

32494 results found.

  1. GRB010923 as seen by BeppoSAX GRBM
  2. GRB010928(=H1770): Localization of a Long GRB by HETE
  3. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  4. GRB010921, negative optical observations
  5. GRB010921 field photometry
  6. GRB 010921 DPOSS Images Available
  7. IPN triangulation of GRB010921 (=H1761)
  8. H1761: A Bright GRB Detected by HETE
  9. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  10. GRB001109, Host Galaxy Astrometry
  11. GRB000926, Host Galaxy Observations
  12. GRB001109, Host Galaxy Spectroscopic Observations
  13. Probable SGR or Short Duration GRB Detected by HETE
  14. GCN and HETE status
  15. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  16. GRB 010222 - WHT BVRI images
  17. SGR1900+14 burst seen by HETE: BeppoSAX data
  18. GRB 010629 Optical Observations
  19. GRB010629: Optical Observations
  20. SGR1900+14: High Fluence Burst Localized by HETE
  21. GRB010629, optical observations
  22. IPN triangulation of GRB010629
  23. SGR1900+14: Second Burst Localized by HETE
  24. SGR1900+14: A Burst Localized by HETE
  25. Possible burst from SGR1806-20
  26. SGR1806-20: A Second, Intense Burst Localized by HETE
  27. IPN triangulation of GRB010613
  28. IPN triangulation of GRB010612
  29. IPN triangulation of GRB010612
  30. HETE Fully-Automated GCN Notices
  31. GRB000301C: Late-time HST/STIS observation
  32. GRB000418: HST/STIS Second-epoch Observations
  33. X-ray precursors to the large flare from SGR 1900+14
  34. GRB010214, optical observations
  35. SGR 1900+14: No evidence of extended X-ray emission
  36. SGR 1900+14 : RXTE observations
  37. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  38. SGR1900+14 - correction
  39. SGR1900+14
  40. SGR 1900+14: Correction to GCN 1049
  41. Millimeter observation of SGR 1900+14
  42. SGR 1900+14: Detection of extended X-ray emission
  43. Chandra Observations of SGR 1900+14
  44. SGR 1900+14, Chandra observations
  45. Chandra Observations of SGR 1900+14
  46. Possible precursor to the SGR1900+14 giant burst
  47. SGR1900+14, I-band observations
  48. IPN Triangulation of the Giant Flare from SGR1900+14
  49. GRB 010326b Optical Observations
  50. GRB010412: Optical observations
  51. GRB010412: Optical observations
  52. IPN Triangulation of GRB010412
  53. GRB Observation Report
  54. REVISED LOCATION OF GRB010326A
  55. GRB 980326: Late-time HST/STIS observations
  56. GRB010324, field photometry
  57. GRB010326B, field photometry
  58. GRB010326, field photometry
  59. GRB010220, field photometry
  60. Further Optical Observations of GRB 010324
  61. GRB010222, CXO X-ray observations
  62. GRB010324: BeppoSAX/GRBM data
  63. GRB010324, optical observations
  64. Duration, ECT, peak flux and fluence of GRB010324
  65. Optical Observations of GRB 010324
  66. IPN TRIANGULATION OF GRB010324
  67. GRB990705, VLT-FORS1 observations of the host galaxy
  68. GRB010222, late-time optical observation
  69. GRB 010222 - HEGRA GeV/TeV Observations
  70. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  71. GRB010222: Chandra X-ray Observatory Observation
  72. GRB010222: Sub-millimeter vanishing act
  73. GRB010222 - Optical observation
  74. GRB 010222, Optical Observations
  75. GRB010220 optical obsercations
  76. GRB010222 - Optical observation
  77. GRB 010222: High-Resolution Keck Spectroscopy
  78. GRB010222: Optical observation and decay
  79. GRB 010214, I-band data
  80. Sub-millimeter Excess/GRB 010222
  81. GRB 010222
  82. GRB 010222 HST/Chandra TOO
  83. GRB010222 further R-band photometry
  84. GRB010222: R-band data
  85. GRB010222 Optical observations
  86. GRB 010222: Keck Spectroscopy
  87. GRB010222 further R-band photometry
  88. GRB010222, possible increase of optical decay slope
  89. GRB010222: fading behavior
  90. GRB 010222 BV optical observations
  91. GRB010222 R-BAND OBSERVATION
  92. GRB 010220: Near-IR Observations
  93. GRB010214 follow-up from Hanle
  94. GRB 010222: Near-IR Observations
  95. GRB 010222: Optical Observations
  96. GRB 010222, Decay Slope Confirmed
  97. GRB010222: Another absorption line system
  98. GRB010222: Optical decay slope
  99. GRB 010214, Optical Observations
  100. GRB010222: Sub-millimeter detection

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