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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').
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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"

24598 results found.

  1. GRB 010921: HST Detection of the Afterglow and Host Galaxy
  2. GRB 970828: HST Observations of the Host Galaxy
  3. GRB 000131: HST Detection of the Host Galaxy
  4. GRB 970828: HST Observations of the Host Galaxy
  5. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  6. GRB011019: Subaru Optical Observations
  7. GRB 011030 I-band Observations
  8. GRB 011030 K-band Observations
  9. GRB010921, optical observations
  10. GRB011030 - further refinement WFC position
  11. GRB 011030, Radio observations
  12. GRB011030: radio search
  13. GRB 010921: Possible supernova component
  14. GRB010921, optical observation at early time
  15. GRB 010921, I-band observations
  16. GRB011019, optical observations
  17. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  18. GRB 010921: The afterglow of HETE #1761
  19. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  20. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  21. GRB010923 as seen by BeppoSAX GRBM
  22. GRB010928(=H1770): Localization of a Long GRB by HETE
  23. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  24. GRB010921, negative optical observations
  25. GRB010921 field photometry
  26. H1761: A Bright GRB Detected by HETE
  27. GRB000926, Host Galaxy Observations
  28. GRB001109, Host Galaxy Spectroscopic Observations
  29. Probable SGR or Short Duration GRB Detected by HETE
  30. GCN and HETE status
  31. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  32. GRB 010222 - WHT BVRI images
  33. SGR1900+14 burst seen by HETE: BeppoSAX data
  34. GRB 010629 Optical Observations
  35. SGR1900+14: High Fluence Burst Localized by HETE
  36. GRB010629, optical observations
  37. GRB010629: A Burst Localized by HETE
  38. SGR1900+14: Second Burst Localized by HETE
  39. SGR1900+14: A Burst Localized by HETE
  40. SGR1806-20: A Second, Intense Burst Localized by HETE
  41. SGR1806-20: Localization by HETE
  42. HETE Fully-Automated GCN Notices
  43. GRB000301C: Late-time HST/STIS observation
  44. GRB010518: a faint BeppoSAX detection
  45. GRB000418: HST/STIS Second-epoch Observations
  46. X-ray precursors to the large flare from SGR 1900+14
  47. GRB010427, Gamma Ray Observations
  48. SGR 1900+14: No evidence of extended X-ray emission
  49. SGR 1900+14 : RXTE observations
  50. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  51. SGR 1900+14: Correction to GCN 1049
  52. GRB 010222 /corrections to VBT data
  53. Millimeter observation of SGR 1900+14
  54. SGR 1900+14: Detection of extended X-ray emission
  55. SGR 1900+14, Chandra observations
  56. SGR1900+14, I-band observations
  57. GRB010412, field photometry
  58. Giant flare from SGR1900+14
  59. GRB 010326b Optical Observations
  60. GRB010412: BeppoSAX GRBM and WFC observations
  61. GRB010324, revised field photometry
  62. REVISED LOCATION OF GRB010326A
  63. GRB 980326: Late-time HST/STIS observations
  64. GRB010324, field photometry
  65. GRB010326B, field photometry
  66. GRB010326, field photometry
  67. GRB010220, field photometry
  68. Further Optical Observations of GRB 010324
  69. GRB010222, CXO X-ray observations
  70. GRB010324, optical observations
  71. GRB010326B: Localization by HETE (2nd GRB for this date)
  72. GRB 010326 optical observations
  73. GRB010326: Refined Localization by HETE
  74. GRB010326: Localization by HETE
  75. Optical Observations of GRB 010324
  76. GRB010222, late-time optical observation
  77. Support extension to the BeppoSAX mission
  78. GRB 010222 - HEGRA GeV/TeV Observations
  79. GRB010222: Chandra X-ray Observatory Observation
  80. GRB010222: Sub-millimeter vanishing act
  81. GRB010222 - Optical observation
  82. GRB 010222, Optical Observations
  83. GRB010222 - Optical observation
  84. GRB 010222: High-Resolution Keck Spectroscopy
  85. GRB 010214, I-band data
  86. GRB 010222
  87. GRB010222 further R-band photometry
  88. GRB010222: R-band data
  89. GRB 010222: Keck Spectroscopy
  90. GRB010214, field photometry
  91. GRB010222, field photometry
  92. GRB010222 further R-band photometry
  93. GRB010222, possible increase of optical decay slope
  94. GRB 010222 Kyoto optical observation
  95. GRB010222 R-BAND OBSERVATION
  96. GRB010214 follow-up from Hanle
  97. GRB 010222: Near-IR Observations
  98. GRB 010222: Optical Observations
  99. GRB010222: Optical decay slope
  100. GRB 010214, Optical Observations

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