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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"

24671 results found.

  1. GRB001109, Host Galaxy Spectroscopic Observations
  2. Probable SGR or Short Duration GRB Detected by HETE
  3. GCN and HETE status
  4. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  5. GRB 010222 - WHT BVRI images
  6. SGR1900+14 burst seen by HETE: BeppoSAX data
  7. GRB 010629 Optical Observations
  8. SGR1900+14: High Fluence Burst Localized by HETE
  9. GRB010629, optical observations
  10. GRB010629: A Burst Localized by HETE
  11. SGR1900+14: Second Burst Localized by HETE
  12. SGR1900+14: A Burst Localized by HETE
  13. SGR1806-20: A Second, Intense Burst Localized by HETE
  14. SGR1806-20: Localization by HETE
  15. HETE Fully-Automated GCN Notices
  16. GRB000301C: Late-time HST/STIS observation
  17. GRB010518: a faint BeppoSAX detection
  18. GRB000418: HST/STIS Second-epoch Observations
  19. X-ray precursors to the large flare from SGR 1900+14
  20. GRB010427, Gamma Ray Observations
  21. SGR 1900+14: No evidence of extended X-ray emission
  22. SGR 1900+14 : RXTE observations
  23. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  24. SGR 1900+14: Correction to GCN 1049
  25. GRB 010222 /corrections to VBT data
  26. Millimeter observation of SGR 1900+14
  27. SGR 1900+14: Detection of extended X-ray emission
  28. SGR 1900+14, Chandra observations
  29. SGR1900+14, I-band observations
  30. GRB010412, field photometry
  31. Giant flare from SGR1900+14
  32. GRB 010326b Optical Observations
  33. GRB010412: BeppoSAX GRBM and WFC observations
  34. GRB010324, revised field photometry
  35. REVISED LOCATION OF GRB010326A
  36. GRB 980326: Late-time HST/STIS observations
  37. GRB010324, field photometry
  38. GRB010326B, field photometry
  39. GRB010326, field photometry
  40. GRB010220, field photometry
  41. Further Optical Observations of GRB 010324
  42. GRB010222, CXO X-ray observations
  43. GRB010324, optical observations
  44. GRB010326B: Localization by HETE (2nd GRB for this date)
  45. GRB 010326 optical observations
  46. GRB010326: Refined Localization by HETE
  47. GRB010326: Localization by HETE
  48. Optical Observations of GRB 010324
  49. GRB010222, late-time optical observation
  50. Support extension to the BeppoSAX mission
  51. GRB 010222 - HEGRA GeV/TeV Observations
  52. GRB010222: Chandra X-ray Observatory Observation
  53. GRB010222: Sub-millimeter vanishing act
  54. GRB010222 - Optical observation
  55. GRB 010222, Optical Observations
  56. GRB010222 - Optical observation
  57. GRB 010222: High-Resolution Keck Spectroscopy
  58. GRB 010214, I-band data
  59. GRB 010222
  60. GRB010222 further R-band photometry
  61. GRB010222: R-band data
  62. GRB 010222: Keck Spectroscopy
  63. GRB010214, field photometry
  64. GRB010222, field photometry
  65. GRB010222 further R-band photometry
  66. GRB010222, possible increase of optical decay slope
  67. GRB 010222 Kyoto optical observation
  68. GRB010222 R-BAND OBSERVATION
  69. GRB010214 follow-up from Hanle
  70. GRB 010222: Near-IR Observations
  71. GRB 010222: Optical Observations
  72. GRB010222: Optical decay slope
  73. GRB 010214, Optical Observations
  74. GRB010222, radio observations
  75. GRB010222, optical observations
  76. GRB010222: BeppoSAX/NFI Observations
  77. GRB010214B,Gamma Ray Observations
  78. GRB 010220, simultaneous optical observations
  79. GRB010220: BeppoSAX WFC and GRBM preliminary data
  80. GRB010214, candidate optical afterglow
  81. GRB010214, optical observations
  82. GRB010214: BeppoSAX WFC and GRBM preliminary data
  83. GRB 010214: X-Ray afterglow
  84. GRB 010214 optical observation
  85. GRB010213, Radio Observations
  86. J-Band Observation of GRB 010214.
  87. GRB010213, Near-IR observations
  88. Possible InfraRed Transient of GRB 010214.
  89. GRB 010214, optical observations
  90. GRB010213 detected by HETE
  91. IPN Status Report
  92. HETE Status
  93. IPN/RXTE TRIANGULATION OF GRB010126
  94. GRB010126 Optical Observations
  95. IPN TRIANGULATION OF GRB010126
  96. Optical Observations of GRB 001018 at Keck
  97. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  98. Optical observations of GRB 001018 with JCAM
  99. IPN TRIANGULATION OF GRB010115
  100. IPN TRIANGULATION OF GRB010109

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