実験技術

• 検出器• 粒子（Object）同定• シミュレーション（QCD）

粒子と物質との相互作用

2

荷電 中性

電磁シャワー作る e± γ(π0)

電磁シャワー作らないハドロン レプトン

π±, K±, p μ±

ハドロン レプトン

n ν

荷電粒子

3

荷電 中性EM e± γ No EM

Had Lepπ±, K±, p μ±

Had Lepn ν

4 27. Passage of particles through matter

1

2

3

4

5

6

8

10

1.0 10 100 1000 10 0000.1

Pion momentum (GeV/c)

Proton momentum (GeV/c)

1.0 10 100 10000.1

1.0 10 100 10000.1

1.0 10 100 1000 10 0000.1

!dE/d

x (M

eV g!1 c

m2 )

"# = p/Mc

Muon momentum (GeV/c)

H2 liquid

He gas

CAl

FeSn

Pb

Figure 27.3: Mean energy loss rate in liquid (bubble chamber) hydrogen, gaseoushelium, carbon, aluminum, iron, tin, and lead. Radiative e!ects, relevant formuons and pions, are not included. These become significant for muons in iron for!" >! 1000, and at lower momenta for muons in higher-Z absorbers. See Fig. 27.21.

and atomic excitation. Since dE/dx depends only on !, R/M is a function of E/M orpc/M . In practice, range is a useful concept only for low-energy hadrons (R <! #I , where#I is the nuclear interaction length), and for muons below a few hundred GeV (abovewhich radiative e!ects dominate). R/M as a function of !" = p/Mc is shown for avariety of materials in Fig. 27.4.

The mass scaling of dE/dx and range is valid for the electronic losses described by theBethe-Bloch equation, but not for radiative losses, relevant only for muons and pions.

For a particle with mass M and momentum M!"c, Tmax is given by

Tmax =2mec2 !2"2

1 + 2"me/M + (me/M)2. (27.2)

August 29, 2007 11:19

2 27. Passage of particles through matter

27.2. Electronic energy loss by heavy particles [1–22, 24–30, 82]

Moderately relativistic charged particles other than electrons lose energy in matterprimarily by ionization and atomic excitation. The mean rate of energy loss (or stoppingpower) is given by the Bethe-Bloch equation,

!dE

dx= Kz2 Z

A

1!2

!12

ln2mec2!2"2Tmax

I2 ! !2 ! #(!")2

". (27.1)

Here Tmax is the maximum kinetic energy which can be imparted to a free electron in asingle collision, and the other variables are defined in Table 27.1. With K as defined inTable 27.1 and A in g mol!1, the units are MeV g!1cm2.

In this form, the Bethe-Bloch equation describes the energy loss of pions in a materialsuch as copper to about 1% accuracy for energies between about 6 MeV and 6 GeV(momenta between about 40 MeV/c and 6 GeV/c). At lower energies various corrections

Muon momentum

1

10

100

Sto

ppin

g po

wer

[M

eV c

m2 /

g]

Lin

dhar

d-Sch

arff

Bethe-Bloch Radiative

Radiativeeffects

reach 1%

!" on Cu

Without !

Radiativelosses

"#0.001 0.01 0.1 1 10 100 1000 104 105 106

[MeV/c] [GeV/c]

1001010.1 100101 100101

[TeV/c]

Anderson-Ziegler

Nuclearlosses

Minimumionization

E!c

!$

Fig. 27.1: Stopping power (= "!dE/dx#) for positive muons in copperas a function of !" = p/Mc over nine orders of magnitude in momentum(12 orders of magnitude in kinetic energy). Solid curves indicate thetotal stopping power. Data below the break at !" $ 0.1 are taken fromICRU 49 [2], and data at higher energies are from Ref. 1. Verticalbands indicate boundaries between di!erent approximations discussedin the text. The short dotted lines labeled “µ! ” illustrate the “Barkase!ect,” the dependence of stopping power on projectile charge at very lowenergies [3].

August 29, 2007 11:19

イオン化損失

低運動領域ではdE/dxと運動量から粒子識別可能

電子と光子

電子は制動放射で光子を放出光子は電子・陽電子対を生成

4

27. Passage of particles through matter 15

Results using this formula agree with Tsai’s values to better than 2.5% for all elementsexcept helium, where the result is about 5% low.

Bremsstrahlung

Lead (Z = 82)Positrons

Electrons

Ionization

Møller (e!)

Bhabha (e!)

Positronannihilation

1.0

0.5

0.20

0.15

0.10

0.05(c

m2

g!1 )

E (MeV)1

010 100 1000

1 E!

dE dx

(X0!

1 )

Figure 27.10: Fractional energy loss per radiation length in lead as a function ofelectron or positron energy. Electron (positron) scattering is considered as ionizationwhen the energy loss per collision is below 0.255 MeV, and as Møller (Bhabha)scattering when it is above. Adapted from Fig. 3.2 from Messel and Crawford,Electron-Photon Shower Distribution Function Tables for Lead, Copper, and AirAbsorbers, Pergamon Press, 1970. Messel and Crawford use X0(Pb) = 5.82 g/cm2,but we have modified the figures to reflect the value given in the Table of Atomicand Nuclear Properties of Materials (X0(Pb) = 6.37 g/cm2).

The radiation length in a mixture or compound may be approximated by

1/X0 =!

wj/Xj , (27.23)

where wj and Xj are the fraction by weight and the radiation length for the jth element.

27.4.2. Energy loss by electrons : At low energies electrons and positrons primarilylose energy by ionization, although other processes (Møller scattering, Bhabha scattering,e+ annihilation) contribute, as shown in Fig. 27.10. While ionization loss rates riselogarithmically with energy, bremsstrahlung losses rise nearly linearly (fractional loss isnearly independent of energy), and dominates above a few tens of MeV in most materials

Ionization loss by electrons and positrons di!ers from loss by heavy particles becauseof the kinematics, spin, and the identity of the incident electron with the electrons whichit ionizes. Complete discussions and tables can be found in Refs. 7, 8, and 27.

August 29, 2007 11:19

27. Passage of particles through matter 19

!"#$#%&'%()*+

,&-.

,&/.

,&.

,0&1.,0&(2 ,&/(2 ,&-(2 ,&3(2 ,00&3(2

4.5&6(78&4!&9&:;5

<&(=>()?1(%$7@&!$#$!>A(A

""

B)#CC&C(D$?#%&&4.7)%CE7$#15

B)#CC&C(D$?#%&&4.7)%CE7$#15

,0&1.

,&.

,&/.

,&-.

475&B7).#%&4!#9&F5

!G7+@(?*"

!*A8A)A

!B#1>$#%

!B#1>$#%

!G7+@(?*"

"%HD

"%HD

""

!>A(A

<&(=>()?1(%$7@&!$#$

Figure 27.14: Photon total cross sections as a function of energy in carbon andlead, showing the contributions of di!erent processes:

!p.e. = Atomic photoelectric e!ect (electron ejection, photon absorption)!Rayleigh = Rayleigh (coherent) scattering–atom neither ionized nor excited!Compton = Incoherent scattering (Compton scattering o! an electron)

"nuc = Pair production, nuclear field"e = Pair production, electron field

!g.d.r. = Photonuclear interactions, most notably the Giant Dipole Reso-nance [46]. In these interactions, the target nucleus is broken up.

Data from [47]; parameters for !g.d.r. from [48]. Curves for these and otherelements, compounds, and mixtures may be obtained fromhttp://physics.nist.gov/PhysRefData. The photon total cross section isapproximately flat for at least two decades beyond the energy range shown. Originalfigures courtesy J.H. Hubbell (NIST).

August 29, 2007 11:19

荷電 中性EM e± γ No EM

Had Lepπ±, K±, p μ±

Had Lepn ν

⇒電磁シャワー

ハドロン

強い相互作用によるシャワー‣ Gluon radiation‣ クォークの対生成๏ 実際にはハドロンの生成と消滅✓π0は電磁シャワーになる• E/h=1が良いとされた

5

荷電 中性EM e± γ No EM

Had Lepπ±, K±, p μ±

Had Lepn ν

Radiation / Interaction Length

電磁シャワーのエネルギーが1/e⇐ 1 radiation length (X0)ハドロニックシャワーのエネルギーが1/e⇐ 1 interaction length (λI)

6

X0 (cm) λI (cm)鉛 0.56 17.59鉄 1.76 16.78

アルミニウム 8.90 39.72水 36.08 83.3

7

強い相互作用

電磁相互作用

ATLAS検出器

8

CMS検出器

9

Drift Tube Chambers ( ) DT

Resistive Plate Chambers ( )RPC

MUON BARREL

ECAL

SUPERCONDUCTINGCOIL

IRON YOKE

TRACKER

MUONENDCAPS

HCAL

CALORIMETERS

Cathode Strip Chambers ( )CSCResistive Plate Chambers ( )RPC

silicon pixels/microstrips

plastic scintillator/brass sandwich

scintillating PbWO4 crystals

Total weight: 12,500 tOverall diameter: 15 mOverall length: 21.6 mMagnetic field: 4 Tesla

検出器

検出器の分類

荷電粒子のdE/dxを変換‣ 光（シンチレーション，チェレンコフ）๏ 固体　プラスチック，様々な結晶๏ 液体　水，液体アルゴン，などなど‣ 電気信号を電極から読み出す๏ 固体　シリコン等๏ ガス　様々なチェンバー

11

位置，エネルギー，時間情報

シンチレータ

最も基本的な検出器の一つ粒子のdE/dxにより蛍光‣ 有機，無機，液体などなど様々な種類‣ 反応速度の速いものが多い単体でカロリメータとして用いるときは高い密度が必要‣ エネルギーを全て落とすように

光電子増倍管(PMT)などの光検出器が必要12

13

シリコン検出器

S/Nが格段に大きい‣ バンドギャップが小さい๏ Egap = 1.12eVE(e-h pair) = 3.6eV~30 eV for gas

‣ 密度が高い 2.33g/cm3๏ 106 e-h /μm for MIP信号の移動速度が速い固体なので構造を作りやすい

14

ガスチェンバーdE/dxでガスをイオン化電極としてワイヤや極板ガスの工夫比較的遅い比較的安い

15

28. Particle detectors 1

28. PARTICLE DETECTORSRevised 2007 (see the various sections for authors).

28.1. Summary of detector spatial resolution, temporal resolution,and deadtime

In this section we give various parameters for common detector components. Thequoted numbers are usually based on typical devices, and should be regarded only asrough approximations for new designs. More detailed discussions of detectors and theirunderlying physics can be found in books by Ferbel [1], Grupen [2], Kleinknecht [3],Knoll [4], and Green [5]. In Table 28.1 are given typical resolutions and deadtimes ofcommon detectors.

Table 28.1: Typical resolutions and deadtimes of common detectors. RevisedSeptember 2003 by R. Kadel (LBNL).

Resolution DeadDetector Type Accuracy (rms) Time Time

Bubble chamber 10–150 µm 1 ms 50 msa

Streamer chamber 300 µm 2 µs 100 msProportional chamber 50–300 µmb,c,d 2 ns 200 nsDrift chamber 50–300 µm 2 nse 100 nsScintillator — 100 ps/nf 10 nsEmulsion 1 µm — —Liquid Argon Drift [Ref. 6] !175–450 µm ! 200 ns ! 2 µsGas Micro Strip [Ref. 7] 30–40 µm < 10 ns —Resistive Plate chamber [Ref. 8] ! 10 µm 1–2 ns —Silicon strip pitch/(3 to 7)g h h

Silicon pixel 2 µmi h h

a Multiple pulsing time.b 300 µm is for 1 mm pitch.c Delay line cathode readout can give ±150 µm parallel to anode wire.d wirespacing/

"12.

e For two chambers.f n = index of refraction.g The highest resolution (“7”) is obtained for small-pitch detectors (! 25 µm) with

pulse-height-weighted center finding.h Limited by the readout electronics [9]. (Time resolution of # 25 ns is planned for

the ATLAS SCT.)i Analog readout of 34 µm pitch, monolithic pixel detectors.

CITATION: W.-M. Yao et al., Journal of Physics G 33, 1 (2006)

available on the PDG WWW pages (URL: http://pdg.lbl.gov/) November 29, 2007 14:50

飛跡検出器

荷電粒子の位置の測定‣ （磁場中で）運動量の測定

๏ 運動量分解能 ~ 1/(BL2)

‣ 粒子の衝突・崩壊地点の同定

16

pT (GeV/c) = 0.3Br(T · m)mv2

r= q(v ×B) → pT = qBr

s ∼=L2

8r=

0.3L2B

8pT

σpT

pT|meas =

σ(s)s

∼=σ(x) · pT

0.3 · BL2

�720/(N + 4)

σvertex ∼ σposition(1 + Rin/Rout)Rin

Rout

実際にはsagittaを測る

位置分解能

Binary情報（ヒットのあるなし）のみ

アナログ情報をプラス

17

�∆x2� =

� d/2−d/2 x2dx� d/2−d/2 dx

=d2

12σ =

d√12

η =QR

QL + QR=

x

d

σ ∼ N

S× (

dη

dx)−1

37!"#$%&'()*+,-++./0+12

d

x

QL

QR

xp

3456

• 43789:;<=>?@A<B<C xpD

EF

• G<=>?@AHQLI

J<=>?@AHQR<

34DKLMNOP

飛跡検出器開発で考えること

位置分解能向上 ⇒ 微細な分割‣ データ量の増大による読み出し速度の低下クーロン多重散乱 ⇒ 物質量を減らす

‣ シリコン検出器では冷却が必要 (耐放射線)๏ 冷却系と物質量との兼ね合い主流はシリコンとガスチェンバー‣ 高精度→シリコン，大きな検出器→ガス‣ 最近はファイバートラッカーも流行

18

12 27. Passage of particles through matter

1 30.3 30 30010 100 1000!"!!(= p/m"

0.50

0.55

0.60

0.65

0.70

0.75

0.80

0.85

0.90

0.95

1.00

(#p/x" / d

E/dx m

in

80 #m (18.7 mg/cm2)160 #m (37.4 mg/cm2)

x = 640 #m (149 mg/cm2)

320 #m (74.7 mg/cm2)

Figure 27.8: Most probable energy loss in silicon, scaled to the mean loss of aminimum ionizing particle, 388 eV/µm (1.66 MeV g!1cm2). See full-color versionon color pages at end of book.

If we define

!0 = ! rmsplane =

1!2

!rmsspace . (27.11)

then it is su!cient for many applications to use a Gaussian approximation for the central98% of the projected angular distribution, with a width given by [32,33]

!0 =13.6 MeV

"cpz

!x/X0

"1 + 0.038 ln(x/X0)

#. (27.12)

Here p, "c, and z are the momentum, velocity, and charge number of the incident particle,and x/X0 is the thickness of the scattering medium in radiation lengths (defined below).This value of !0 is from a fit to Moliere distribution [31] for singly charged particles with" = 1 for all Z, and is accurate to 11% or better for 10!3 < x/X0 < 100.

Eq. (27.12) describes scattering from a single material, while the usual problem involvesthe multiple scattering of a particle traversing many di"erent layers and mixtures. Since itis from a fit to a Moliere distribution, it is incorrect to add the individual !0 contributionsin quadrature; the result is systematically too small. It is much more accurate to applyEq. (27.12) once, after finding x and X0 for the combined scatterer.

Lynch and Dahl have extended this phenomenological approach, fitting Gaussiandistributions to a variable fraction of the Moliere distribution for arbitrary scatterers [33],and achieve accuracies of 2% or better.

August 29, 2007 11:19

電磁カロリメータ

電磁シャワー‣ 制動輻射 + 対生成

‣ Critical Energy Ec (制動輻射とdE/dxによるエネルギー損失が等しい）まで続く

19

エネルギーに依存しないλpair =

97X0E = E0e

−x/X0

27. Passage of particles through matter 23

so that distance is measured in units of radiation length and energy in units of criticalenergy.

0.000

0.025

0.050

0.075

0.100

0.125

0

20

40

60

80

100

(1/E

0)dE/d

t

t = depth in radiation lengths

Nu

mbe

r cros

sin

g pl

ane

30 GeV electronincident on iron

Energy

Photons! 1/6.8

Electrons

0 5 10 15 20

Figure 27.18: An EGS4 simulation of a 30 GeV electron-induced cascade in iron.The histogram shows fractional energy deposition per radiation length, and thecurve is a gamma-function fit to the distribution. Circles indicate the number ofelectrons with total energy greater than 1.5 MeV crossing planes at X0/2 intervals(scale on right) and the squares the number of photons with E ! 1.5 MeV crossingthe planes (scaled down to have same area as the electron distribution).

Longitudinal profiles from an EGS4 [52] simulation of a 30 GeV electron-inducedcascade in iron are shown in Fig. 27.18. The number of particles crossing a plane (veryclose to Rossi’s ! function [4]) is sensitive to the cuto" energy, here chosen as a totalenergy of 1.5 MeV for both electrons and photons. The electron number falls o" morequickly than energy deposition. This is because, with increasing depth, a larger fractionof the cascade energy is carried by photons. Exactly what a calorimeter measures dependson the device, but it is not likely to be exactly any of the profiles shown. In gas countersit may be very close to the electron number, but in glass Cherenkov detectors and otherdevices with “thick” sensitive regions it is closer to the energy deposition (total tracklength). In such detectors the signal is proportional to the “detectable” track length Td,which is in general less than the total track length T . Practical devices are sensitive toelectrons with energy above some detection threshold Ed, and Td = T F (Ed/Ec). Ananalytic form for F (Ed/Ec) obtained by Rossi [4] is given by Fabjan [53]; see alsoAmaldi [54].

The mean longitudinal profile of the energy deposition in an electromagnetic cascade

August 29, 2007 11:19

エネルギー測定[検出器の反応 ∝ エネルギー] が重要分解能

‣ エネルギーあたりの信号が大きいほどよい‣ 一般に

ハドロンカロリメータでも一緒20

ノイズcalibration, non-linearityなど

ハドロンシャワー

非常に複雑な発展‣ 電磁シャワーに比べて分解能が悪い電磁シャワーよりも長く，広く拡がる‣ λI > X0

21

X0

λa

X0, λ a

[cm

]

Z

λa and X0 in cm

サンプリング・カロリメータ

Absorber (シャワーを発生) ＋ detector （荷電粒子のdE/dxを測定）‣ Samplingによるシャワー生成のfluctuationが分解能を制限Absorber‣ 電磁：鉛など大きなZ‣ ハドロン：鉄，銅など（Aが大きく廉価）Detector‣ シンチレータ

22

全吸収型カロリメータAbsorber = Detector‣ 全エネルギーを検出するので分解能がよいシンチレータかチェレンコフ‣ 最近はシンチレータが主流

23

16 28. Particle detectors

Table 28.4: Properties of several inorganic crystal scintillators. Most of the notation isdefined in Sec. 6 of this Review.

Parameter: ! MP X!0 R!

M dE/dx "!I #decay "max n! Relative Hygro- d(LY)/dT

output† scopic?Units: g/cm3 "C cm cm MeV/cm cm ns nm %/"C‡

NaI(Tl) 3.67 651 2.59 4.13 4.8 42.9 230 410 1.85 100 yes !0.2

BGO 7.13 1050 1.12 2.23 9.0 22.8 300 480 2.15 21 no !0.9

BaF2 4.89 1280 2.03 3.10 6.6 30.7 630s 300s 1.50 36s no !1.3s

0.9f 220f 3.4f "0f

CsI(Tl) 4.51 621 1.86 3.57 5.6 39.3 1300 560 1.79 165 slight 0.3

CsI(pure) 4.51 621 1.86 3.57 5.6 39.3 35s 420s 1.95 3.6s slight !1.3

6f 310f 1.1f

PbWO4 8.3 1123 0.89 2.00 10.2 20.7 30s 425s 2.20 0.083s no !2.7

10f 420f 0.29f

LSO(Ce) 7.40 2050 1.14 2.07 9.6 20.9 40 420 1.82 83 no !0.2

GSO(Ce) 6.71 1950 1.38 2.23 8.9 22.2 600s 430 1.85 3s no !0.1

56f 30f

! Numerical values calculated using formulae in this review.! Refractive index at the wavelength of the emission maximum.† Relative light output measured for samples of 1.5 X0 cube with a Tyvek paperwrapping and a full end face coupled to a photodetector. The quantum e!ciencies of thephotodetector is taken out.‡ Variation of light yield with temperature evaluated at the room temperature.f = fast component, s = slow component

where L is the path length in the radiator, !(E) is the e!ciency for collecting theCherenkov light and transducing it in photoelectrons, and "2/(re mec2) = 370 cm"1eV"1.

The quantities ! and #c are functions of the photon energy E. However, since thetypical energy dependent variation of the index of refraction is modest, a quantity calledthe Cherenkov detector quality factor N0 can be defined as

N0 ="2z2

re mec2

!! dE , (28.5)

so thatNp.e. ! LN0"sin2 #c# . (28.6)

We take z = 1, the usual case in high-energy physics, in the following discussion.This definition of the quality factor N0 is not universal, nor, indeed, very useful for

situations where the geometrical photon collection e!ciency (!coll) varies substantially for

November 29, 2007 14:50

電磁カロリメータの性能比較

24

48 28. Particle detectors

Table 28.7: Resolution of typical electromagnetic calorimeters. E is in GeV.

Technology (Experiment) Depth Energy resolution Date

NaI(Tl) (Crystal Ball) 20X0 2.7%/E1/4 1983

Bi4Ge3O12 (BGO) (L3) 22X0 2%/!

E " 0.7% 1993

CsI (KTeV) 27X0 2%/!

E " 0.45% 1996

CsI(Tl) (BaBar) 16–18X0 2.3%/E1/4 " 1.4% 1999

CsI(Tl) (BELLE) 16X0 1.7% for E! > 3.5 GeV 1998

PbWO4 (PWO) (CMS) 25X0 3%/!

E " 0.5% " 0.2/E 1997

Lead glass (OPAL) 20.5X0 5%/!

E 1990

Liquid Kr (NA48) 27X0 3.2%/!

E" 0.42% " 0.09/E 1998

Scintillator/depleted U 20–30X0 18%/!

E 1988(ZEUS)

Scintillator/Pb (CDF) 18X0 13.5%/!

E 1988

Scintillator fiber/Pb 15X0 5.7%/!

E " 0.6% 1995spaghetti (KLOE)

Liquid Ar/Pb (NA31) 27X0 7.5%/!

E " 0.5% " 0.1/E 1988

Liquid Ar/Pb (SLD) 21X0 8%/!

E 1993

Liquid Ar/Pb (H1) 20–30X0 12%/!

E " 1% 1998

Liquid Ar/depl. U (DØ) 20.5X0 16%/!

E " 0.3% " 0.3/E 1993

Liquid Ar/Pb accordion 25X0 10%/!

E " 0.4% " 0.3/E 1996(ATLAS)

in the power-law approximation the ratio of the responses for incident pions and incidentelectrons is given by “!/e”= 1 # (1 # h/e)(E/E0)m!1. With or without the power-lawapproximation the response for pions is not a linear function of energy for e/h $= 1. (Butin any case, as the energy increases a larger and larger fraction of the energy is transferredto !0’s, and “!/e”% 1.) If e/h = 1.0 the calorimeter is said to be compensating. Ife/h di!ers from unity by more than 5% or 10%, detector performance is compromisedbecause of fluctuations in the !0 content of the cascades. This results in (a) a skewedsignal distribution and (b) an almost-constant contribution to detector resolution whichis proportional to the degree of noncompensation |1 # h/e|. The coe"cient relating thesize of the constant term to |1 # h/e| is 14% according to FLUKA simulations [130],and 21% according to Wigmans’ calculations [131]. (Wigmans now prefers a di!erentapproach to the “constant term” [125]. )

November 29, 2007 14:50

sampling

全吸収

チェレンコフ

シンチレーター

シンチレーター

液体アルゴン

ミューオン検出器考えるべきこと‣ ハドロンのpunch throughを除くための十分な物質量

‣ 1番外側 ⇒ 巨大 ⇒ たくさん安く๏ ガスチェンバーが主流‣ 磁場 (Solenoid+Toroid vs Solenoid only)

25Imagnet

B

coil

solenoid

!"#$%&'

()*#+,-./01

2.3456

toroid

Imagnet

B

789:;()<2.=

>?4@AB9'CD=

EF4GH

789:GHII,IJKL9:GH

()MNO4PQ

ATLASDzero

CMSCDF

トリガー

ゴミの山から針を探すLHCの場合‣ 40MHzで衝突‣ O(100Hz)で記録๏ 105減らす๏ 2MB x 400Hz = 800MB / s

๏ 1年を107秒として8PB / year

26

（例として）ミューオントリガー

数多くの違った閾値，prescale27

[GeV]µµm1 10 210

]-1 [G

eVµ

µ/d

mµ

µdN

-110

1

10

210

310

410

510

[GeV]µµm1 10 210

]-1 [G

eVµ

µ/d

mµ

µdN

-110

1

10

210

310

410

510

ATLAS Preliminary= 7 TeVsData 2010,

-1 40 pb L EF_mu15

/J/

’ (1S)(2S) Z

ATLAS vs CMS (1)

ATLASは検出器数が多過ぎる28

ATLAS CMS

Tracker si-pixel, si-strip, transition radiation tube

si-pixel, si-strip

EM Cal. Pb + L.Ar PbWO4

Had. Cal. (π) Fe+scintillator, Cu+L.Ar, Cu+W+L.Ar

Cu + scintillator

muon RPC, drift tube, TGC drift tube, RPC

magnet solenoid (2T) + toroid solenoid (4T)

ATLAS vs CMS (2)

コメントは口頭で

29

ATLAS |η| resolution CMS |η| resolution

Tracker 2.5 2.5

EM Cal. 3.2 3.0

Had. Cal. (π)

4.9 3.0

muon 2.7 2.5% @100GeV 2.4 2% @100GeV

σpT

pT∼ 0.036%× pT ⊕ 1.3%

σpT

pT∼ 0.015%× pT ⊕ 0.5%

σE

E∼ 10%√

E⊕ 0.7%

σE

E∼ 2.7%√

E⊕ 0.6%

σE

E∼ 50%√

E⊕ 3%

σE

E∼ 65%√

E⊕ 5%