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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

41685 results found.

  1. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  2. GRB010921: Spectroscopy of the Host Galaxy
  3. GRB 010921: The afterglow of HETE #1761
  4. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  5. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  6. GRB010923 as seen by BeppoSAX GRBM
  7. GRB010928(=H1770): Localization of a Long GRB by HETE
  8. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  9. GRB010921, negative optical observations
  10. GRB010921 field photometry
  11. GRB010921 Optical Observations
  12. GRB 010921 DPOSS Images Available
  13. IPN triangulation of GRB010921 (=H1761)
  14. H1761: A Bright GRB Detected by HETE
  15. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  16. HETE Trigger #1760 (GRB 010920B?): a new optical source
  17. HETE Trigger #1759 (GRB 010920?) optical observations
  18. GRB001109, Host Galaxy Astrometry
  19. GRB000926, Host Galaxy Observations
  20. GRB001109, Host Galaxy Spectroscopic Observations
  21. Probable SGR or Short Duration GRB Detected by HETE
  22. GRB000926 Host Galaxy Observations
  23. GRB 010222: HST observations -- host galaxy and late-time decay
  24. BeppoSAX/GRBM detection of GRB 010801
  25. GCN and HETE status
  26. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  27. BeppoSAX/GRBM detection of GRB010728
  28. GRB 010222 - WHT BVRI images
  29. SGR1900+14 burst seen by HETE: BeppoSAX data
  30. GRB 010629 Optical Observations
  31. GRB010629: Optical Observations
  32. SGR1900+14: High Fluence Burst Localized by HETE
  33. GRB010629, optical observations
  34. IPN triangulation of GRB010629
  35. GRB010629: A Burst Localized by HETE
  36. SGR1900+14: Second Burst Localized by HETE
  37. SGR1900+14: A Burst Localized by HETE
  38. Possible burst from SGR1806-20
  39. IPN detection of SGR1900+14
  40. SGR1806-20: A Second, Intense Burst Localized by HETE
  41. GRB 00630: Host Galaxy
  42. SGR1806-20: Localization by HETE
  43. IPN triangulation of GRB010613
  44. IPN triangulation of GRB010612
  45. IPN triangulation of GRB010612
  46. HETE Fully-Automated GCN Notices
  47. GRB000301C: Late-time HST/STIS observation
  48. GRB010518: a faint BeppoSAX detection
  49. GRB000418: HST/STIS Second-epoch Observations
  50. X-ray precursors to the large flare from SGR 1900+14
  51. GRB010214, optical observations
  52. GRB010427, Gamma Ray Observations
  53. SGR 1900+14: No evidence of extended X-ray emission
  54. SGR 1900+14 : RXTE observations
  55. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  56. SGR1900+14 - correction
  57. SGR1900+14
  58. SGR 1900+14: Correction to GCN 1049
  59. GRB 010222 /corrections to VBT data
  60. Millimeter observation of SGR 1900+14
  61. SGR 1900+14: Detection of extended X-ray emission
  62. Chandra Observations of SGR 1900+14
  63. SGR 1900+14, Chandra observations
  64. Chandra Observations of SGR 1900+14
  65. Possible precursor to the SGR1900+14 giant burst
  66. SGR1900+14, I-band observations
  67. IPN Triangulation of the Giant Flare from SGR1900+14
  68. GRB010412, field photometry
  69. Giant flare from SGR1900+14
  70. GRB 010326b Optical Observations
  71. GRB010412: Optical observations
  72. GRB010412: Optical observations
  73. GRB010412: BeppoSAX GRBM and WFC observations
  74. IPN Triangulation of GRB010412
  75. GRB Observation Report
  76. GRB010324, revised field photometry
  77. REVISED LOCATION OF GRB010326A
  78. GRB 980326: Late-time HST/STIS observations
  79. GRB010324, field photometry
  80. GRB010326B, field photometry
  81. GRB010326, field photometry
  82. GRB010220, field photometry
  83. Further Optical Observations of GRB 010324
  84. GRB010222, CXO X-ray observations
  85. GRB 010326A: Further optical observations
  86. GRB010324: BeppoSAX/GRBM data
  87. GRB 010326B: Optical observations
  88. GRB010324, optical observations
  89. GRB010326B: Localization by HETE (2nd GRB for this date)
  90. GRB010326: Localization by HETE
  91. Duration, ECT, peak flux and fluence of GRB010324
  92. Optical Observations of GRB 010324
  93. IPN TRIANGULATION OF GRB010324
  94. GRB990705, VLT-FORS1 observations of the host galaxy
  95. GRB010222, late-time optical observation
  96. Support extension to the BeppoSAX mission
  97. GRB 010222 - HEGRA GeV/TeV Observations
  98. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  99. GRB010222: Chandra X-ray Observatory Observation
  100. GRB010222: Sub-millimeter vanishing act

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