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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"

38337 results found.

  1. GRB 011019 optical observation
  2. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  3. GRB011019: Subaru Optical Observations
  4. GRB 011030 I-band Observations
  5. GRB 011030 K-band Observations
  6. GRB010921, optical observations
  7. GRB 011030, WSRT radio observations
  8. GRB011030 - further refinement WFC position
  9. GRB 011030, Radio observations
  10. GRB011030: radio search
  11. GRB 011030, R-band observations
  12. X-ray rich GRB011030: BeppoSAX refined positions
  13. BeppoSAX ALERT: Possible X-ray rich GRB011030
  14. GRB 010921: Possible supernova component
  15. GRB011019: NEAT Optical Observations
  16. GRB011019: ROTSE-III optical observations
  17. GRB010921, optical observation at early time
  18. GRB 010921, I-band observations
  19. GRB011019, optical observations
  20. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  21. GRB010921: Spectroscopy of the Host Galaxy
  22. GRB 010921: The afterglow of HETE #1761
  23. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  24. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  25. GRB010923 as seen by BeppoSAX GRBM
  26. GRB010928(=H1770): Localization of a Long GRB by HETE
  27. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  28. GRB010921, negative optical observations
  29. GRB010921 field photometry
  30. GRB010921 Optical Observations
  31. GRB 010921 DPOSS Images Available
  32. IPN triangulation of GRB010921 (=H1761)
  33. H1761: A Bright GRB Detected by HETE
  34. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  35. HETE Trigger #1760 (GRB 010920B?): a new optical source
  36. HETE Trigger #1759 (GRB 010920?) optical observations
  37. GRB001109, Host Galaxy Astrometry
  38. GRB000926, Host Galaxy Observations
  39. GRB001109, Host Galaxy Spectroscopic Observations
  40. Probable SGR or Short Duration GRB Detected by HETE
  41. GRB000926 Host Galaxy Observations
  42. GRB 010222: HST observations -- host galaxy and late-time decay
  43. BeppoSAX/GRBM detection of GRB 010801
  44. GCN and HETE status
  45. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  46. BeppoSAX/GRBM detection of GRB010728
  47. GRB 010222 - WHT BVRI images
  48. SGR1900+14 burst seen by HETE: BeppoSAX data
  49. GRB 010629 Optical Observations
  50. GRB010629: Optical Observations
  51. SGR1900+14: High Fluence Burst Localized by HETE
  52. GRB010629, optical observations
  53. IPN triangulation of GRB010629
  54. GRB010629: A Burst Localized by HETE
  55. SGR1900+14: Second Burst Localized by HETE
  56. SGR1900+14: A Burst Localized by HETE
  57. Possible burst from SGR1806-20
  58. IPN detection of SGR1900+14
  59. SGR1806-20: A Second, Intense Burst Localized by HETE
  60. GRB 00630: Host Galaxy
  61. SGR1806-20: Localization by HETE
  62. IPN triangulation of GRB010613
  63. IPN triangulation of GRB010612
  64. HETE Fully-Automated GCN Notices
  65. GRB000301C: Late-time HST/STIS observation
  66. GRB010518: a faint BeppoSAX detection
  67. GRB000418: HST/STIS Second-epoch Observations
  68. X-ray precursors to the large flare from SGR 1900+14
  69. GRB010214, optical observations
  70. GRB010427, Gamma Ray Observations
  71. SGR 1900+14 : RXTE observations
  72. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  73. SGR1900+14
  74. SGR 1900+14: Correction to GCN 1049
  75. GRB 010222 /corrections to VBT data
  76. Millimeter observation of SGR 1900+14
  77. SGR 1900+14: Detection of extended X-ray emission
  78. Chandra Observations of SGR 1900+14
  79. SGR 1900+14, Chandra observations
  80. Chandra Observations of SGR 1900+14
  81. Possible precursor to the SGR1900+14 giant burst
  82. SGR1900+14, I-band observations
  83. IPN Triangulation of the Giant Flare from SGR1900+14
  84. GRB010412, field photometry
  85. GRB 010326b Optical Observations
  86. GRB010412: Optical observations
  87. GRB010412: Optical observations
  88. GRB010412: BeppoSAX GRBM and WFC observations
  89. IPN Triangulation of GRB010412
  90. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  91. BeppoSAX GRB ALERT: GRB010412
  92. GRB010324, revised field photometry
  93. REVISED LOCATION OF GRB010326A
  94. GRB 980326: Late-time HST/STIS observations
  95. GRB010324, field photometry
  96. GRB010326B, field photometry
  97. GRB010326, field photometry
  98. GRB010220, field photometry
  99. Further Optical Observations of GRB 010324
  100. GRB010222, CXO X-ray observations

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