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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"

36186 results found.

  1. GRB011019: Subaru Optical Observations
  2. GRB 011030 I-band Observations
  3. GRB 011030 K-band Observations
  4. GRB010921, optical observations
  5. GRB 011030, WSRT radio observations
  6. GRB011030 - further refinement WFC position
  7. GRB 011030, Radio observations
  8. GRB 011030, R-band observations
  9. BeppoSAX ALERT: Possible X-ray rich GRB011030
  10. GRB 010921: Possible supernova component
  11. GRB011019: NEAT Optical Observations
  12. GRB010921, optical observation at early time
  13. GRB 010921, I-band observations
  14. GRB011019: Optical observations
  15. GRB011019, optical observations
  16. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  17. GRB010921: Spectroscopy of the Host Galaxy
  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. GRB010921 Optical Observations
  27. GRB 010921 DPOSS Images Available
  28. IPN triangulation of GRB010921 (=H1761)
  29. H1761: A Bright GRB Detected by HETE
  30. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  31. HETE Trigger #1760 (GRB 010920B?): a new optical source
  32. HETE Trigger #1759 (GRB 010920?) optical observations
  33. GRB001109, Host Galaxy Astrometry
  34. GRB000926, Host Galaxy Observations
  35. GRB001109, Host Galaxy Spectroscopic Observations
  36. Probable SGR or Short Duration GRB Detected by HETE
  37. GRB000926 Host Galaxy Observations
  38. GRB 010222: HST observations -- host galaxy and late-time decay
  39. BeppoSAX/GRBM detection of GRB 010801
  40. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  41. GRB 010222 - WHT BVRI images
  42. GRB 010629 Optical Observations
  43. GRB010629: Optical Observations
  44. GRB010629, optical observations
  45. IPN triangulation of GRB010629
  46. GRB010629: A Burst Localized by HETE
  47. Possible burst from SGR1806-20
  48. IPN detection of SGR1900+14
  49. GRB 00630: Host Galaxy
  50. IPN triangulation of GRB010613
  51. IPN triangulation of GRB010612
  52. HETE Fully-Automated GCN Notices
  53. GRB000301C: Late-time HST/STIS observation
  54. GRB010518: a faint BeppoSAX detection
  55. GRB000418: HST/STIS Second-epoch Observations
  56. GRB010427, Gamma Ray Observations
  57. SGR1900+14
  58. GRB 010222 /corrections to VBT data
  59. Possible precursor to the SGR1900+14 giant burst
  60. IPN Triangulation of the Giant Flare from SGR1900+14
  61. GRB010412, field photometry
  62. GRB 010326b Optical Observations
  63. GRB010412: Optical observations
  64. GRB010412: Optical observations
  65. IPN Triangulation of GRB010412
  66. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  67. BeppoSAX GRB ALERT: GRB010412
  68. GRB Observation Report
  69. GRB010324, revised field photometry
  70. REVISED LOCATION OF GRB010326A
  71. GRB 980326: Late-time HST/STIS observations
  72. GRB010324, field photometry
  73. GRB010326B, field photometry
  74. GRB010326, field photometry
  75. GRB010220, field photometry
  76. Further Optical Observations of GRB 010324
  77. GRB 010326A: Further optical observations
  78. GRB010324: BeppoSAX/GRBM data
  79. GRB 010326B: Optical observations
  80. GRB010324, optical observations
  81. GRB010326B: Localization by HETE (2nd GRB for this date)
  82. GRB 010326: Optical observations
  83. GRB 010326 optical observations
  84. GRB010326: Refined Localization by HETE
  85. GRB010326: Localization by HETE
  86. Duration, ECT, peak flux and fluence of GRB010324
  87. Optical Observations of GRB 010324
  88. IPN TRIANGULATION OF GRB010324
  89. GRB990705, VLT-FORS1 observations of the host galaxy
  90. GRB010222, late-time optical observation
  91. Support extension to the BeppoSAX mission
  92. GRB 010222 - HEGRA GeV/TeV Observations
  93. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  94. GRB010222: Chandra X-ray Observatory Observation
  95. GRB010222: Sub-millimeter vanishing act
  96. GRB 010222, Optical Observations
  97. GRB 010222: High-Resolution Keck Spectroscopy
  98. GRB 010214, I-band data
  99. Sub-millimeter Excess/GRB 010222
  100. GRB 010222

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