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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"

42627 results found.

  1. GRB010928(=H1770): Localization of a Long GRB by HETE
  2. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  3. GRB010921, negative optical observations
  4. GRB010921 field photometry
  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. GCN and HETE status
  19. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  20. BeppoSAX/GRBM detection of GRB010728
  21. GRB 010222 - WHT BVRI images
  22. SGR1900+14 burst seen by HETE: BeppoSAX data
  23. GRB 010629 Optical Observations
  24. GRB010629: Optical Observations
  25. SGR1900+14: High Fluence Burst Localized by HETE
  26. GRB010629, optical observations
  27. IPN triangulation of GRB010629
  28. GRB010629: A Burst Localized by HETE
  29. SGR1900+14: Second Burst Localized by HETE
  30. SGR1900+14: A Burst Localized by HETE
  31. Possible burst from SGR1806-20
  32. IPN detection of SGR1900+14
  33. SGR1806-20: A Second, Intense Burst Localized by HETE
  34. GRB 00630: Host Galaxy
  35. SGR1806-20: Localization by HETE
  36. IPN triangulation of GRB010613
  37. IPN triangulation of GRB010612
  38. IPN triangulation of GRB010612
  39. HETE Fully-Automated GCN Notices
  40. GRB000301C: Late-time HST/STIS observation
  41. GRB010518: a faint BeppoSAX detection
  42. GRB000418: HST/STIS Second-epoch Observations
  43. X-ray precursors to the large flare from SGR 1900+14
  44. GRB010214, optical observations
  45. GRB010427, Gamma Ray Observations
  46. SGR 1900+14: No evidence of extended X-ray emission
  47. SGR 1900+14 : RXTE observations
  48. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  49. SGR1900+14
  50. SGR 1900+14: Detection of extended X-ray emission
  51. Chandra Observations of SGR 1900+14
  52. SGR 1900+14, Chandra observations
  53. Chandra Observations of SGR 1900+14
  54. Possible precursor to the SGR1900+14 giant burst
  55. SGR1900+14, I-band observations
  56. IPN Triangulation of the Giant Flare from SGR1900+14
  57. GRB010412, field photometry
  58. Giant flare from SGR1900+14
  59. GRB 010326b Optical Observations
  60. GRB010412: Optical observations
  61. GRB010412: Optical observations
  62. GRB010412: BeppoSAX GRBM and WFC observations
  63. IPN Triangulation of GRB010412
  64. BeppoSAX GRB ALERT: GRB010412
  65. GRB Observation Report
  66. GRB010324, revised field photometry
  67. REVISED LOCATION OF GRB010326A
  68. GRB 980326: Late-time HST/STIS observations
  69. GRB010324, field photometry
  70. GRB010326B, field photometry
  71. GRB010326, field photometry
  72. GRB010220, field photometry
  73. Further Optical Observations of GRB 010324
  74. GRB010222, CXO X-ray observations
  75. GRB 010326A: Further optical observations
  76. GRB010324: BeppoSAX/GRBM data
  77. GRB 010326B: Optical observations
  78. GRB010324, optical observations
  79. GRB010326B: Localization by HETE (2nd GRB for this date)
  80. GRB 010326: Optical observations
  81. GRB 010326 optical observations
  82. GRB010326: Refined Localization by HETE
  83. GRB010326: Localization by HETE
  84. Duration, ECT, peak flux and fluence of GRB010324
  85. Optical Observations of GRB 010324
  86. IPN TRIANGULATION OF GRB010324
  87. GRB990705, VLT-FORS1 observations of the host galaxy
  88. GRB010222, late-time optical observation
  89. Support extension to the BeppoSAX mission
  90. GRB 010222 - HEGRA GeV/TeV Observations
  91. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  92. GRB010222: Chandra X-ray Observatory Observation
  93. GRB010222: Sub-millimeter vanishing act
  94. GRB010222 - Optical observation
  95. GRB 010222, Optical Observations
  96. GRB010220 optical obsercations
  97. GRB010222 - Optical observation
  98. GRB 010222: High-Resolution Keck Spectroscopy
  99. GRB010222: Optical observation and decay
  100. GRB 010214, I-band data

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