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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"

33764 results found.

  1. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  2. GRB010921, negative optical observations
  3. GRB010921 field photometry
  4. GRB010921 Optical Observations
  5. GRB 010921 DPOSS Images Available
  6. IPN triangulation of GRB010921 (=H1761)
  7. H1761: A Bright GRB Detected by HETE
  8. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  9. HETE Trigger #1760 (GRB 010920B?): a new optical source
  10. HETE Trigger #1759 (GRB 010920?) optical observations
  11. GRB001109, Host Galaxy Astrometry
  12. GRB000926, Host Galaxy Observations
  13. GRB001109, Host Galaxy Spectroscopic Observations
  14. Probable SGR or Short Duration GRB Detected by HETE
  15. GRB000926 Host Galaxy Observations
  16. GRB 010222: HST observations -- host galaxy and late-time decay
  17. BeppoSAX/GRBM detection of GRB 010801
  18. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  19. GRB 010222 - WHT BVRI images
  20. GRB 010629 Optical Observations
  21. GRB010629: Optical Observations
  22. GRB010629, optical observations
  23. IPN triangulation of GRB010629
  24. GRB010629: A Burst Localized by HETE
  25. Possible burst from SGR1806-20
  26. IPN detection of SGR1900+14
  27. GRB 00630: Host Galaxy
  28. IPN triangulation of GRB010613
  29. IPN triangulation of GRB010612
  30. HETE Fully-Automated GCN Notices
  31. GRB000301C: Late-time HST/STIS observation
  32. GRB010518: a faint BeppoSAX detection
  33. GRB000418: HST/STIS Second-epoch Observations
  34. GRB010427, Gamma Ray Observations
  35. SGR1900+14
  36. GRB 010222 /corrections to VBT data
  37. Possible precursor to the SGR1900+14 giant burst
  38. IPN Triangulation of the Giant Flare from SGR1900+14
  39. GRB010412, field photometry
  40. GRB 010326b Optical Observations
  41. GRB010412: Optical observations
  42. GRB010412: Optical observations
  43. IPN Triangulation of GRB010412
  44. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  45. BeppoSAX GRB ALERT: GRB010412
  46. GRB Observation Report
  47. GRB010324, revised field photometry
  48. REVISED LOCATION OF GRB010326A
  49. GRB 980326: Late-time HST/STIS observations
  50. GRB010324, field photometry
  51. GRB010326B, field photometry
  52. GRB010326, field photometry
  53. GRB010220, field photometry
  54. Further Optical Observations of GRB 010324
  55. GRB 010326A: Further optical observations
  56. GRB010324: BeppoSAX/GRBM data
  57. GRB 010326B: Optical observations
  58. GRB010324, optical observations
  59. GRB010326B: Localization by HETE (2nd GRB for this date)
  60. GRB 010326: Optical observations
  61. GRB 010326 optical observations
  62. GRB010326: Refined Localization by HETE
  63. GRB010326: Localization by HETE
  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. Support extension to the BeppoSAX mission
  70. GRB 010222 - HEGRA GeV/TeV Observations
  71. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  72. GRB010222: Chandra X-ray Observatory Observation
  73. GRB010222: Sub-millimeter vanishing act
  74. GRB 010222, Optical Observations
  75. GRB 010222: High-Resolution Keck Spectroscopy
  76. GRB 010214, I-band data
  77. Sub-millimeter Excess/GRB 010222
  78. GRB 010222
  79. GRB 010222 HST/Chandra TOO
  80. GRB 010222
  81. GRB010222 further R-band photometry
  82. GRB010222: R-band data
  83. GRB010222 Optical observations
  84. GRB 010222: Keck Spectroscopy
  85. GRB010214, field photometry
  86. GRB010222, field photometry
  87. GRB010222 further R-band photometry
  88. GRB010222, possible increase of optical decay slope
  89. GRB 010222 Kyoto optical observation
  90. GRB010222: fading behavior
  91. GRB 010222 BV optical observations
  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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