T?O??? ??? ???????G?? ?O? ????????O? ????O?

1
T?O??? ??? ???????G???O? ????????O? ????O?

• ?.?????OS??S
• ???????O? G.?S????I??S

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Ge???? ?e????af?

• ??sa????
• ?pa?t??µe?? ?e???a
• ??a?????s? ?e?t?????a?
• ???ß??µata ?a??? ?e?t?????a?

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ATLAS
Muon System RPC, TGC, CSC, MDT
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MDT
MONITORED DRIFT TUBES
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MDT

• 2 Multilayer
• 3 ? 4 Tubes t? ???e layer

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Drift Tube
???µa ?e???? 93.0 Ar , 7.0 CO2 ??es? 3 bar
?p????s?µ??? 3 ?at? ß????, ap? W / Re 973
rw 250.5µm Va 3080 V ?e?t?µ??? µe t?s?
3507g
r ? ap?stas? ap? t?? ????a t??
?????d???
S????a? router 1.5 ????µ????? p???? 40020 µm
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Te???a

• ????e?s?.
• ?at?????? e????e?a
• G?a e??e?? a???a s 107 barn
• ?e?a?t??? d?e??as?e? µp????? ?a d?s???
  ???t?sµ?
• ???t?sµ??.
• ?????e?a ?at?f????
• ? e?ap?µ????sa p?e? sta e-
• G?a ??p??a keV pa?ap??? ????µe d-rays

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Te???a

• ? p??a??t?ta ??a e- ?a ??e? e????e?a ? e??a?
• ? ?t?µ???? ????µ??
• ? ?t?µ??? ?????
• x Reduce Thickness e?? µe z t? f??t??
• ???????????ta? t?? P(E) ß??s???µe t? p????? t??
• d?e?e?µ???? e- µe ? ?0 ,????ta? t??
  µ???st?
• ep?t?ept? e????e?a p?? µp??e? ?a a?ta??a??e? se
  µ?a
• a?t?d?as? ap? s?et???st??? ????µat???

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Te???a

• ?p?? t? te?e?ta?? ?s??e? ?ta? ?0ltlt ?? .
• ?etaf??? e- ?a? ???t?? sta a???a
• Se ?e?µ??? ?s????p?a ?? ta??t?te? d????ta? ap?
• t?? ?ata??µ? Maxwell
• ???? t?? m p?? e??a? st?? pa????µast? uegtgtu???
• st??? 20?C ue104 m/s u??? 102 m/s

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Te???a

• ?p? t?? ????t??? ?e???a t?? ae???? ????µe t??
  e???t?s? t?? p?????? t?? f??t?sµ???? s?µat?d??? ?
  ap? t?? ??s? x µet? ap? ????? t

D s??te?est?? d????s??(u?/3) ?p?? ? ? µ?s?
e?e??e?? d?ad??µ? (??a ??ass??? ?da????
a???? e??a?
µe s0 t?? ????? e?e??? d?at?µ? t??
ae????)
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Te???a

• ? ?p? t?? ep?d?as? t?? ??e?t?. ?ed???
• e- ? ????d?, ???ta ? ???d?.
• ? ???? s??????se?? ap??t??? udrift
  (µe
• t t?? µ?s? ????? e?e??e???
• d?ad??µ??)
• p??
• ?pe?t??eta?
• st? ?e?µ???.

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Te???a

• ? ????t???t?ta µudrift/E.
• ? ?da???? a???a s?. Einstein

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Te???a

• ? ud,e- e?a?t?ta?
• ?s???? ap? t? ?.
• ?e ?1kV/cm
• ud,e-106m/s ?µ??
• t?te t? D a????eta?
• p????µe????
• d?asp???.

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Te???a

• ?e efa?µ??? ?a???t???? ped??? ? ???? d??aµ??
• Lorentz ? µe ?eH/m,
  e?? ? ????a t??
• ta??t?ta? µe t?? d??aµ???? ??aµµ?? e??a?
  a?arctan(?t)

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?????st?ß?da (Avalanche)

• ?? ta e- ap? t?? p??t??e?? ???t?sµ? ap??t?s???
• a??et? ? t?te p???a???? ?? a?t? ???t?sµ? st?
• a????. ?µ???? ?a? ta ??a, ?.?.?. ?p?te ???t? st?
  s??µa
• p?? ????µe µe???? ped?? ????µe ?????st?ß?da.

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?????st?ß?da (Avalanche)

• dnnadx
• ?p?? t? dn e??a? ta ??a e- p?? d?µ?????????a?
• st?? d?ad??µ? dx ap? n a?????.
• a1/? (s??te?. Townsend) d??e? t?? p??a??t?ta
• ???t?sµ?? a?? µ???da µ?????. ???????????ta?
• ????µe nn0eax µ?s? a?t?? ????µe t??
• p???ap?as?ast??? pa?????ta ? n/n0eax.
• ?µ?? ??a µ? ?µ??e??
• ped?a aa(x) ?p?te
• ?? ???? a???s?? t?? ? p??? t? breakdown d??eta?
• ap? t?? s?????? Raether ?ta? ax20 t?te ?108.

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?p????? ?e????

• ?e????? 10ade? a????? e- de? µp????? ?a d?s???
• s?µa ??a?? p??? a????e?s?. ? e??s??s? ???eta?
  µ?s?
• avalanche se ?at?????? µ??µa p?? pe????e? ?a?
• e????e? a???? (µ? ??e?t?a???t???). ?a Ar, Kr, Xe
• ????? µ???? d??aµ??? ???t?sµ?? a??? t? Ar e??a?
  t?
• f????te??.
• ??p??e? ap? t?? p???p???se?? e??a? µ? t?????, µ?
  
• e?f?e?ta, µ???? d????s?, resolution 80-90µm,
  a??a???
• se ?, ? 0,3 a??a?? se a????s? lt15µm, ?a?? gain.
• ??p???? e??s??se?? 102. ?? Ar de? ?pe?ßa??e?
  103-104.

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?p????? ?e????
Ar 11.6 eV
Al 5.9 eV
????

• G?a ap?f??? a?ep???µ?t?? d?e??as??? eµp???t????µe
• t? a???? µa? µe ???? (s?????? µe?a??µ????) p??
• ap????f? ta f?t???a µ?s? s?ed?se??, ??µ????
• d?e??as???, s??t???sµ?? ?.a.
• ? ?.?. t? CH4 ap????f? st?? pe????? 7,9-14,5 eV.
• ? ? d?ad??as?a ???eta? quenching.
• ? ?? ??? µ??µa µp??e? ?a ft?se? se e??s??s? sta
  106.

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Drift Tube
?????? ???????
S????a? a???µ?????
S??µa
???s??s? e- p??? t? s??µa
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MDT
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MDT
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??a?atas?e??
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??a?atas?e??
Track reconstruction µe p??sd????sµ?
efapt?µ???? t?? a?a?atas?e?asµ???? ?????? µe
???s? e??e?a? e?a??st?? tet?a?????.
?p? 2 ??????? ?? d??at?? efapt?µ??e? e??a? 4.
?p? pe??ss?te???? e??a? s?????? µ?a. ?.?. ap? 3.
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??a?atas?e??
St??? ??????? ap? t??? ?p????? de? pe???e? t? µ
(µp?e ??aµµ?) t? s?µa e??a? ????ß??.
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???ß??µata

• ?etat?p?s? t?? s??µat?? ap? t?? ??s? t?? ??e?
• ep?d?as? st?? ap?stas? p?? ?a ?????? ta e- ?a?

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???ß??µata

• f?s??? st?? ?ata??µ? t?? ped???.

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???ß??µata

• ? ???a?s? t?? ?a??µ?? e??a? ??a e??s?? µe????
• p??ß??µa.

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???ß??µata
40 cm ap? t?? ???d?
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???ß??µata
p??? ???t? st?? ???d?
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???ß??µata
???t?s? t?? BIL ???? d?af???? ?e?µ???as?a? 5 ?C
t?? 2 multilayer. ? ???µa?a e??a? se µm
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???ß??µata
??????t?a ???t?s? t?? BIL ?p? t?? ep?d?as? t??
ß????? t??. ? ???µa?a e??a? se µm
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S?????

• ????sµ?? ae???? a??? ?e?t?????a?
• T??aµ?? ???s??s?? MDT
• ???ß??µata

??ß?????af?a

• Principles of Operation of Multiwire Proportional
  and Drift Chambers, F. Sauli
• Studies on Ageing and Reanimation of Drift Tubes
  for the ATLAS Muon System, V. Paschhoff
• Atlas Muon Spectrometer Technical Design Report
• www.cern.ch
• www.google.com