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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"

41624 results found.

  1. IPN triangulation of GRB010921 (=H1761)
  2. HETE Trigger #1760 (GRB 010920B?): a new optical source
  3. HETE Trigger #1759 (GRB 010920?) optical observations
  4. GRB000926, Host Galaxy Observations
  5. GRB001109, Host Galaxy Spectroscopic Observations
  6. GRB000926 Host Galaxy Observations
  7. GRB 010222: HST observations -- host galaxy and late-time decay
  8. GCN and HETE status
  9. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  10. GRB 010222 - WHT BVRI images
  11. SGR1900+14 burst seen by HETE: BeppoSAX data
  12. GRB 010629 Optical Observations
  13. GRB010629: Optical Observations
  14. SGR1900+14: High Fluence Burst Localized by HETE
  15. GRB010629, optical observations
  16. IPN triangulation of GRB010629
  17. GRB010629: A Burst Localized by HETE
  18. SGR1900+14: Second Burst Localized by HETE
  19. SGR1900+14: A Burst Localized by HETE
  20. IPN detection of SGR1900+14
  21. SGR1806-20: A Second, Intense Burst Localized by HETE
  22. GRB 00630: Host Galaxy
  23. SGR1806-20: Localization by HETE
  24. IPN triangulation of GRB010613
  25. GRB000301C: Late-time HST/STIS observation
  26. GRB010518: a faint BeppoSAX detection
  27. GRB000418: HST/STIS Second-epoch Observations
  28. X-ray precursors to the large flare from SGR 1900+14
  29. GRB010214, optical observations
  30. GRB010427, Gamma Ray Observations
  31. SGR 1900+14: No evidence of extended X-ray emission
  32. SGR 1900+14 : RXTE observations
  33. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  34. SGR1900+14
  35. GRB 010222 /corrections to VBT data
  36. Millimeter observation of SGR 1900+14
  37. SGR 1900+14: Detection of extended X-ray emission
  38. Chandra Observations of SGR 1900+14
  39. SGR 1900+14, Chandra observations
  40. Chandra Observations of SGR 1900+14
  41. SGR1900+14, I-band observations
  42. GRB010412, field photometry
  43. GRB 010326b Optical Observations
  44. GRB010412: Optical observations
  45. GRB010412: Optical observations
  46. GRB010412: BeppoSAX GRBM and WFC observations
  47. IPN Triangulation of GRB010412
  48. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  49. GRB Observation Report
  50. GRB010324, revised field photometry
  51. REVISED LOCATION OF GRB010326A
  52. GRB 980326: Late-time HST/STIS observations
  53. GRB010324, field photometry
  54. GRB010326B, field photometry
  55. GRB010326, field photometry
  56. GRB010220, field photometry
  57. Further Optical Observations of GRB 010324
  58. GRB010222, CXO X-ray observations
  59. GRB 010326A: Further optical observations
  60. GRB010324: BeppoSAX/GRBM data
  61. GRB 010326B: Optical observations
  62. GRB010324, optical observations
  63. GRB010326B: Localization by HETE (2nd GRB for this date)
  64. GRB 010326: Optical observations
  65. GRB 010326 optical observations
  66. GRB010326: Refined Localization by HETE
  67. GRB010326: Localization by HETE
  68. Duration, ECT, peak flux and fluence of GRB010324
  69. Optical Observations of GRB 010324
  70. IPN TRIANGULATION OF GRB010324
  71. GRB990705, VLT-FORS1 observations of the host galaxy
  72. GRB010222, late-time optical observation
  73. GRB 010222 - HEGRA GeV/TeV Observations
  74. Congratulate Scott on the 1000th GRB Coordinates Network Circular!
  75. GRB010222: Chandra X-ray Observatory Observation
  76. GRB010222: Sub-millimeter vanishing act
  77. GRB010222 - Optical observation
  78. GRB 010222, Optical Observations
  79. GRB010220 optical obsercations
  80. GRB010222 - Optical observation
  81. GRB 010222: High-Resolution Keck Spectroscopy
  82. GRB010222: Optical observation and decay
  83. GRB 010214, I-band data
  84. Sub-millimeter Excess/GRB 010222
  85. GRB 010222
  86. GRB 010222 HST/Chandra TOO
  87. GRB010222 further R-band photometry
  88. GRB010222 Optical observations
  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: fading behavior
  96. GRB 010222 BV optical observations
  97. GRB010220, Optical Observations
  98. GRB010222 R-BAND OBSERVATION
  99. GRB 010220: Near-IR Observations
  100. GRB010214 follow-up from Hanle

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