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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"

24373 results found.

  1. GRB 970828: HST Observations of the Host Galaxy
  2. GRB 000131: HST Detection of the Host Galaxy
  3. GRB 970828: HST Observations of the Host Galaxy
  4. GRB010921, optical observation
  5. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  6. GRB011019: Subaru Optical Observations
  7. GRB010921, optical observation at early time
  8. GRB 010921, I-band observations
  9. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  10. GRB010921: Spectroscopy of the Host Galaxy
  11. GRB010923 as seen by BeppoSAX GRBM
  12. GRB010928(=H1770): Localization of a Long GRB by HETE
  13. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  14. GRB010921, negative optical observations
  15. GRB010921 Optical Observations
  16. H1761: A Bright GRB Detected by HETE
  17. HETE Trigger #1760 (GRB 010920B?): a new optical source
  18. HETE Trigger #1759 (GRB 010920?) optical observations
  19. GRB 010222: HST observations -- host galaxy and late-time decay
  20. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  21. SGR1900+14 burst seen by HETE: BeppoSAX data
  22. SGR1900+14: High Fluence Burst Localized by HETE
  23. GRB010629: A Burst Localized by HETE
  24. SGR1900+14: Second Burst Localized by HETE
  25. SGR1900+14: A Burst Localized by HETE
  26. Possible burst from SGR1806-20
  27. IPN detection of SGR1900+14
  28. SGR1806-20: A Second, Intense Burst Localized by HETE
  29. SGR1806-20: Localization by HETE
  30. HETE Fully-Automated GCN Notices
  31. GRB000301C: Late-time HST/STIS observation
  32. GRB010518: a faint BeppoSAX detection
  33. GRB000418: HST/STIS Second-epoch Observations
  34. X-ray precursors to the large flare from SGR 1900+14
  35. GRB010427, Gamma Ray Observations
  36. SGR 1900+14 : RXTE observations
  37. Chandra Observations of SGR 1900+14
  38. Possible precursor to the SGR1900+14 giant burst
  39. SGR1900+14, I-band observations
  40. IPN Triangulation of the Giant Flare from SGR1900+14
  41. Giant flare from SGR1900+14
  42. GRB010412: BeppoSAX GRBM and WFC observations
  43. BeppoSAX GRB: extension of BSAX operations upto April 30, 2002
  44. REVISED LOCATION OF GRB010326A
  45. GRB 980326: Late-time HST/STIS observations
  46. GRB010324, field photometry
  47. GRB010326B, field photometry
  48. GRB010326, field photometry
  49. Further Optical Observations of GRB 010324
  50. GRB010324: BeppoSAX/GRBM data
  51. GRB010324, optical observations
  52. GRB010326B: Localization by HETE (2nd GRB for this date)
  53. GRB010326: Refined Localization by HETE
  54. GRB010326: Localization by HETE
  55. Duration, ECT, peak flux and fluence of GRB010324
  56. GRB010222, late-time optical observation
  57. Support extension to the BeppoSAX mission
  58. GRB010222: Sub-millimeter vanishing act
  59. Sub-millimeter Excess/GRB 010222
  60. GRB 010222
  61. GRB010222 further R-band photometry
  62. GRB 010222: Keck Spectroscopy
  63. GRB010222 further R-band photometry
  64. GRB010222, possible increase of optical decay slope
  65. GRB010220, Optical Observations
  66. GRB010222 R-BAND OBSERVATION
  67. GRB 010222: Near-IR Observations
  68. GRB010222, optical observations
  69. Redshift of the Optical Transient of GRB010222
  70. GRB010214B,Gamma Ray Observations
  71. GRB 010220, simultaneous optical observations
  72. GRB010220: BeppoSAX WFC and GRBM preliminary data
  73. GRB010214: BeppoSAX WFC and GRBM preliminary data
  74. GRB 010214: X-Ray afterglow
  75. J-Band Observation of GRB 010214.
  76. GRB010214, optical observations
  77. GRB010213, optical observations
  78. Possible InfraRed Transient of GRB 010214.
  79. GRB010214 Optical Observation
  80. GRB010213 detected by HETE
  81. IPN Status Report
  82. HETE Status
  83. GRB010126 opt. obs.
  84. GRB010126: CONCAM crude optical limits during GRB
  85. GRB010126, TNG R-band observations
  86. GRB010126 optical observations
  87. GRB010126: Optical observations
  88. IPN/RXTE TRIANGULATION OF GRB010126
  89. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  90. GRB 001212 Optical Observation
  91. GRB 001212 Optical Observation
  92. GRB 001212 optical observation
  93. GRB 001212 possible OA
  94. Confirmation of IPN position for GRB001204
  95. GRB 001105, R-band observation
  96. GRB 001025B, Optical obervations
  97. GRB 991208: HST Imaging of the Host Galaxy
  98. ASM Localization of GRB 001025
  99. GRB001018, Gamma Ray Observations
  100. V,R,I band observations of GRB000926

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