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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').

32081 results found.

  1. GRB011030 - further refinement WFC position
  2. GRB 011030, Radio observations
  3. GRB 011030, R-band observations
  4. BeppoSAX ALERT: Possible X-ray rich GRB011030
  5. GRB 010921: Possible supernova component
  6. GRB011019: NEAT Optical Observations
  7. GRB010921, optical observation at early time
  8. GRB 010921, I-band observations
  9. GRB011019: Optical observations
  10. GRB011019, optical observations
  11. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  12. GRB010921: Spectroscopy of the Host Galaxy
  13. GRB 010921: The afterglow of HETE #1761
  14. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  15. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  16. GRB010923 as seen by BeppoSAX GRBM
  17. GRB010928(=H1770): Localization of a Long GRB by HETE
  18. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  19. GRB010921, negative optical observations
  20. GRB010921 field photometry
  21. GRB010921 Optical Observations
  22. GRB 010921 DPOSS Images Available
  23. IPN triangulation of GRB010921 (=H1761)
  24. H1761: A Bright GRB Detected by HETE
  25. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  26. HETE Trigger #1760 (GRB 010920B?): a new optical source
  27. HETE Trigger #1759 (GRB 010920?) optical observations
  28. GRB001109, Host Galaxy Astrometry
  29. GRB000926, Host Galaxy Observations
  30. GRB001109, Host Galaxy Spectroscopic Observations
  31. Probable SGR or Short Duration GRB Detected by HETE
  32. GRB000926 Host Galaxy Observations
  33. GRB 010222: HST observations -- host galaxy and late-time decay
  34. BeppoSAX/GRBM detection of GRB 010801
  35. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  36. GRB 010222 - WHT BVRI images
  37. GRB 010629 Optical Observations
  38. GRB010629: Optical Observations
  39. GRB010629, optical observations
  40. IPN triangulation of GRB010629
  41. GRB010629: A Burst Localized by HETE
  42. Possible burst from SGR1806-20
  43. IPN detection of SGR1900+14
  44. GRB 00630: Host Galaxy
  45. IPN triangulation of GRB010613
  46. IPN triangulation of GRB010612
  47. HETE Fully-Automated GCN Notices
  48. GRB000301C: Late-time HST/STIS observation
  49. GRB010518: a faint BeppoSAX detection
  50. GRB000418: HST/STIS Second-epoch Observations
  51. GRB010427, Gamma Ray Observations
  52. SGR1900+14
  53. GRB 010222 /corrections to VBT data
  54. Possible precursor to the SGR1900+14 giant burst
  55. IPN Triangulation of the Giant Flare from SGR1900+14
  56. GRB010412, field photometry
  57. GRB 010326b Optical Observations
  58. GRB010412: Optical observations
  59. GRB010412: Optical observations
  60. IPN Triangulation of GRB010412
  61. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  62. BeppoSAX GRB ALERT: GRB010412
  63. GRB Observation Report
  64. GRB010324, revised field photometry
  65. REVISED LOCATION OF GRB010326A
  66. GRB 980326: Late-time HST/STIS observations
  67. GRB010324, field photometry
  68. GRB010326B, field photometry
  69. GRB010326, field photometry
  70. GRB010220, field photometry
  71. Further Optical Observations of GRB 010324
  72. GRB 010326A: Further optical observations
  73. GRB010324: BeppoSAX/GRBM data
  74. GRB 010326B: Optical observations
  75. GRB010324, optical observations
  76. GRB010326B: Localization by HETE (2nd GRB for this date)
  77. GRB 010326: Optical observations
  78. GRB 010326 optical observations
  79. GRB010326: Refined Localization by HETE
  80. GRB010326: Localization by HETE
  81. Duration, ECT, peak flux and fluence of GRB010324
  82. Optical Observations of GRB 010324
  83. IPN TRIANGULATION OF GRB010324
  84. GRB990705, VLT-FORS1 observations of the host galaxy
  85. GRB010222, late-time optical observation
  86. Support extension to the BeppoSAX mission
  87. GRB 010222 - HEGRA GeV/TeV Observations
  88. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  89. GRB010222: Chandra X-ray Observatory Observation
  90. GRB010222: Sub-millimeter vanishing act
  91. GRB 010222, Optical Observations
  92. GRB 010222: High-Resolution Keck Spectroscopy
  93. GRB 010214, I-band data
  94. Sub-millimeter Excess/GRB 010222
  95. GRB 010222
  96. GRB 010222 HST/Chandra TOO
  97. GRB 010222
  98. GRB010222 further R-band photometry
  99. GRB010222: R-band data
  100. GRB010222 Optical observations

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