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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"

45648 results found.

  1. GRB 011030: TNG K-band observation
  2. XRF011030: J and K band observations
  3. GRB011030, optical observation
  4. XRF011030: Chandra Observations
  5. GRB 011030: K-band observations
  6. GRB011030: Z-band observations
  7. GRB 011030 R band observations
  8. GRB 011030 I-band Observation
  9. The X-ray Flash 011030 ('GRB 011030')
  10. Non-triggered burst 011030 ("GRB 011030")
  11. The Radio Afterglow from the X-ray Rich GRB 011030
  12. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  13. GRB 970828: HST Observations of the Host Galaxy
  14. GRB 000131: HST Detection of the Host Galaxy
  15. GRB 970828: HST Observations of the Host Galaxy
  16. GRB010921, optical observation
  17. GRB 011019 optical observation
  18. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  19. GRB011019: Subaru Optical Observations
  20. GRB 011030 I-band Observations
  21. GRB 011030 K-band Observations
  22. GRB010921, optical observations
  23. GRB 011030, WSRT radio observations
  24. GRB011030 - further refinement WFC position
  25. GRB 011030, Radio observations
  26. GRB011030: radio search
  27. GRB 011030, R-band observations
  28. X-ray rich GRB011030: BeppoSAX refined positions
  29. BeppoSAX ALERT: Possible X-ray rich GRB011030
  30. GRB 010921: Possible supernova component
  31. GRB011019: NEAT Optical Observations
  32. GRB011019: ROTSE-III optical observations
  33. GRB010921, optical observation at early time
  34. GRB 010921, I-band observations
  35. GRB011019: Optical observations
  36. GRB011019, optical observations -- correction
  37. GRB011019, optical observations
  38. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  39. GRB010921: Spectroscopy of the Host Galaxy
  40. GRB 010921: The afterglow of HETE #1761
  41. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  42. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  43. GRB010923 as seen by BeppoSAX GRBM
  44. GRB010928(=H1770): Localization of a Long GRB by HETE
  45. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  46. GRB010921, negative optical observations
  47. GRB010921 field photometry
  48. GRB010921 Optical Observations
  49. GRB 010921 DPOSS Images Available
  50. IPN triangulation of GRB010921 (=H1761)
  51. H1761: A Bright GRB Detected by HETE
  52. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  53. HETE Trigger #1760 (GRB 010920B?): a new optical source
  54. HETE Trigger #1759 (GRB 010920?) optical observations
  55. GRB001109, Host Galaxy Astrometry
  56. GRB000926, Host Galaxy Observations
  57. GRB001109, Host Galaxy Spectroscopic Observations
  58. Probable SGR or Short Duration GRB Detected by HETE
  59. GRB000926 Host Galaxy Observations
  60. GRB 010222: HST observations -- host galaxy and late-time decay
  61. BeppoSAX/GRBM detection of GRB 010801
  62. GCN and HETE status
  63. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  64. BeppoSAX/GRBM detection of GRB010728
  65. GRB 010222 - WHT BVRI images
  66. SGR1900+14 burst seen by HETE: BeppoSAX data
  67. GRB 010629 Optical Observations
  68. GRB010629: Optical Observations
  69. SGR1900+14: High Fluence Burst Localized by HETE
  70. GRB010629, optical observations
  71. IPN triangulation of GRB010629
  72. GRB010629: A Burst Localized by HETE
  73. SGR1900+14: Second Burst Localized by HETE
  74. SGR1900+14: A Burst Localized by HETE
  75. Possible burst from SGR1806-20
  76. IPN detection of SGR1900+14
  77. SGR1806-20: A Second, Intense Burst Localized by HETE
  78. GRB 00630: Host Galaxy
  79. SGR1806-20: Localization by HETE
  80. IPN triangulation of GRB010613
  81. IPN triangulation of GRB010612
  82. IPN triangulation of GRB010612
  83. HETE Fully-Automated GCN Notices
  84. GRB000301C: Late-time HST/STIS observation
  85. GRB010518: a faint BeppoSAX detection
  86. GRB000418: HST/STIS Second-epoch Observations
  87. X-ray precursors to the large flare from SGR 1900+14
  88. GRB010214, optical observations
  89. GRB010427, Gamma Ray Observations
  90. SGR 1900+14: No evidence of extended X-ray emission
  91. SGR 1900+14 : RXTE observations
  92. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  93. SGR1900+14 - correction
  94. SGR1900+14
  95. SGR 1900+14: Correction to GCN 1049
  96. GRB 010222 /corrections to VBT data
  97. Millimeter observation of SGR 1900+14
  98. SGR 1900+14: Detection of extended X-ray emission
  99. Chandra Observations of SGR 1900+14
  100. SGR 1900+14, Chandra observations

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