ハドロン状態

QQGGPPの生成発見から物性研究へ〜

RRHHIICCからLLHHCCへ
筑波大学 三明康郎

QGP
状態

OBOG会 (2013.9.28)〜

建設

テスト実験

国際

和HH44〜HH2244の学位論文の総数
修士論文

博士論文

75

60

45

30

15

0
1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012
OBOG会 (2013.9.28)✓〜2200年間• 修士；6644• 博士；11226クォーク・グルオンプラズマ（QQGGPP）とは✓ハドロンの構造；• ハドロン（陽子、中性子や中間子）は、11ffmm
程度の大きさを持ち、クォークとグルオンから構成されている。

• クォークとグルオンはハドロンに閉じ込め• 量子色力学（QQCCDD）の世界➡クォークの閉じ込め➡漸近的自由度✓大きさを持つハドロンを狭い空間に多重発生させると（高温・高密度状態）、ハドロンが連結した状態が起こる？

• クォーク・グルオンが比較的大きな体積中を自由に飛び回る状態が実現する。
クォーク・グルオンプラズマ状態
OBOG会 (2013.9.28)

7

宇宙の歴史から見ると、✓QQGGPP  →  陽子や中性子• 時間：ビックバンから数μ秒後• エネルギー密度：>>  11  GGeeVV//ffmm33✓宇宙の晴れ上がり• 時間：ビックバンから4400万年後• 温度：２兆度  KK

OBOG会 (2013.9.28)

8米国・ブルックヘブン国立研究所 (BNL)

スイス・欧州共同原子核研究機構 (CERN)RHIC 加速器 (2000-), 周長 3.8 km

LHC 加速器 (2009-), 周長 27 km√sNN = 200 GeV Au+Au√sNN = 2.76, 5.5 TeV Pb-Pb

RHIC & LHC
高エネルギー重イオン実験の２大拠点

Very HotεBj =Char. Energy Loss of Parton

1 1 dE T
πR 2 cτ 0 dy

≈ 4.6 GeV/fm3> εc ≈ 0.6 −1.2GeV/fm3

２((++11))大トピックス
Very Early thermalization/Strong coupling

CentralPeripheral

25
OBOG会 (2013.9.28)

10

et”.

10-8

10

10-9

10-7

（１）ジェットクエンチ

10-8

10-10

10-11
0

10-9
2

4

6

8

10

12

14

16

18

20

0

2

4

6

（パートンのQQGGPP中の特徴的エネルギー損失）
p (GeV/c)

8

10

12

14

16

18

20

p (GeV/c)

T

T

Fig. 15. Invariant +0 yields measured by PHENIX in peripheral (left) and central (right)”hot/dense/dpT dy
AuAu collisions (squares) [89],compared toQCDmedium”
the (TAA -scaled) pp → +0 + Xdn
cross(cirAAsectionR== [119].
cles) [134] and to a AA
NLO pQCD calculation(curvesandyellowband)”QCD vacuum”N· dn /dp dybinaryT

RAA

Au+Au - 200 GeV (central collisions):
Direct 2 , 2 * [PHENIX]
Inclusive h± [STAR]+0 [PHENIX]. [PHENIX]g
GLV energy loss (dN /dy = 1400)

10Ncoll scaling

1

10-1

pp

Npart scaling

0

2

4

6

8

10

12

14

16
18
20
p (GeV/c)T

Fig. 16. RAA (pT ) measured in central AuAu at 200 GeV for +0 [89] and . [135] mesons,chargedhadrons[114], scatand direct photons [136, 137] compared to theoretical predictions forquenching” in a head-on nucleus-nucleus collision. Two quarks
suffera hardparton energy loss in a dense medium with dN g /dy = 1400 (yellow curve) [138].

✓ １）高運動量粒子の減少
goes out directly to the vacuum, radiates a few gluons and hadronises, the other
低エネルギー衝突では見られないh the dense•･ plasma
created (characterised by transport coefficient q̂, gluon density
topgluonstrahlung
RHIC energies is veryd temperature T ), suffers energy loss due to medium-induced
andclose to the “participant scaling”, (N /2)/N ≈ 0.17,
expected in the strong quenching limit where only hadrons coming from partons✓ ２）相反ジェットの消失
ments outside
into a (quenched) jet.
produced at the surface of the medium show no final-state modifications in theirspectra[141]. From the R one can approximately obtain the fraction of energy✓ エネルギー損失〜数GGeeVV//ffmm
lost, ! = &p /p , via,(36)
ハドロンガスでは考えられないf the first •･proposed“smoking guns” of QGP formation was “jet quench- ! ≈ 1 − Rpedestal and flow subtracted
e. the attenuation or disappearance of the spray of hadrons
resultingwhen the
AuAu and frompp invariant spectra are both a power-law with exponent n, i.e.
→QQGGPP生成の証拠のひとつ•･
dN/dplasmap # p pro[142]. At RHIC (n ≈ 8, R ≈ 0.2), one finds ! ≈ 0.2.
entation of a parton having suffered energy loss in the1/p
dense
part

coll

AA

T

loss

T

loss

T

OBOG会 (2013.9.28)

T

−n
T

1/(n−2)
AA

AA

loss

The high-pT AuAu suppression can be well reproduced by parton energy loss 11

Energy losses in QEDQQEEDD  の場合、

As an illustrative example, we show in Fig. 4 the stopping power of muons in coper. At low and high energies, the collisional (aka “Bethe-Bloch”) and the radiative
nergy losses dominate respectively.

Stopping power [MeV cm2/g]

Energy loss of charged particle in a matter

CCoolllliissiioonnaall✓BBeetthhee--BBlloocchh
Bremsstrahlungµ+ on Cu

100

LindhardScharff

10µ

RRaaddiiaattiivvee✓BBeetthhee--HHeeiittlleerr((tthhiinn;;  LL<<<<λ))✓LLaannddaauu--

3
Bethe-BlochRadiative

AndersonZiegler

Eµc
Minimum
ionization

NuclearlossesPPoommeerraanncchhuukk-MMiiggddaall((tthhiicckk;;  LL>>>>λ))Radiative
lossesRadiative
effects
reach 1%

Without 0
1
0.001

0.01

0.1

1

10

0.1

1

10

100

1

[MeV/c]

12

100

1000

10 4

10 5

10 6

10

100

1

10

100

[GeV/c]Muon momentum[TeV/c]✓ddEE//ddxx  測定→物性を決定
Fig. 4. Stopping
power, −dE/dl, for positive muons in copper as a function of 12 = p/Mc (ormomentum p). The solid curve indicates the total stopping power [15].

• QQEEDDプラズマ中でのエネルギー損失  →  TT  &&  mmDD  を与える

OBOG会 (2013.9.28)

12the parton-medium cross section. Higher-order scatterings (often encoded in a
“K-factor” ≈ 2 – 4) could well result in much larger values of q̂.
QCD example•3, letconsiderconstantan equilibrated
gluon plasma
theusdiffusionD, characterising
the dynamics of heavy non-relativistic
and a strong coupling's ≈(mass
0.5 [10].
At speedthis temperature,
particlesM andv) traversingthe
the plasma, is connected, via the Ein2
density is )g = 16/+
· T 3 ≈ 15 fm−3 (!g = 8+2 /15 · T 4
stein ,(3)relations
2 fm−3 ).
.e. 100 times denser than normal nuclear matterD()
0.15
==2T
/- = T /(M .D )(3)(LO), the Debye mass is mD = (4+'s )1/2 T ≈ 1 GeV. The LO
2 /(2m2 ) ≈ 1.5
to themomentum
diffusion- –freethe average momentum squared gaineds section is *gg # 9+'
mb. Thecoefficient
gluon meansDthe particle per unit-time (related to the transport coefficient as - ≈ q̂ v) – anddium is (g = 1/()byg *gg ) # 0.45 fm (the quark mean-free-path ismomentum drag coefficient .D . colour
1 fm, where CA /Cthe
F = 9/4 is the ratio of gluon-to-quark
sport coefficient is therefore q̂ # m2D /(g # 2.2 GeV2 /fm. Noterical value has2.2
beenobtained witha LO expression
in loss's forMechanisms
of in-medium
energym cross section. Higher-order scatterings (often encoded in aa generalway,
the values
total energy4) could well In
resultin muchlargerof q̂. loss of a particle traversing a medium is the sum of
4 : non-relativistic
stant D, characterising
dynamics
heavycollisionaltheandradiativeofterms&E = &Ecoll + &Erad . Depending on the kinematic
5 inEinM and speed v) region,
traversing
the plasma,is connected,
via thea (colour)chargecan lose energy
a plasma with temperature T mainly by
two mechanisms6 .
D = 2T 2 /- = T /(M .D )
(3)

ria

QQGGPPに特徴的なエネルギー損失

E-!E
diffusion coefficient - – theEaverage momentum
squared gainedr unit-time (related to the transport coefficient as - ≈ q̂ v) – andE
ag coefficient .D .

CCoolllliissiioonnaall

EE-!E

!E

in-medium energy loss!E1

total energy loss of a particle traversing a medium is the sum ofX
ive terms4 : &E = &Ecoll + &Erad . Depending on the kinematic (medium)rge can lose energy5 in a plasma with temperature T mainly by
Fig. 3. Diagrams for collisional (left) and radiative (right) energy losses of a quark of energy
E traversing a quark-gluon medium.

E-!E

•
!E

E

!E

RRaaddiiaattiivvee

Collisional energy loss through elastic scatterings with the medium constituents(Fig. 3, left) dominates at low particle momentum. The average energy loss inE

2

E-!E by powers of ! c # 0.2 GeV fm (other useful equalities:
3 For unit conversion, multiply
10 mb = 1 fm2 , and 1 GeV−2 = 0.389 mb).

4 In addition, synchrotron-,X
Čerenkov- and transition-radiation energy losses can take placerespectively(medium)if the particle interacts with the medium magnetic field, if its velocity is greaterthan the local phase velocity of light, or if it crosses suddenly from one medium to another.
llisional (left) and radiative (right) energy losses of a quark of energy
Also, plasma instabilities may lead to energy losses. Yet, those effects – studied e.g. in [11,uon medium.
12, 13, 14] for QCD plasmas – are generally less important in terms of the amount of Eloss .
5 Note that if the energy of the particle is similar to the plasma temperature, E ∼ O(T ), theparticle can also gain energy while traversing it.
6 Note thatgy loss through elastic
scatterings
with themediumconstituentsthe separation
is notso clear-cut
since the diagrams assume well-defined asympminates at low particle
momentum.
Theoutgoingaverageparticles
energymay
lossstillin be in the medium and further rescatter.
totic outstates, but the

E

2
C
q̂
L
S R

ppQQCCDD• グルーオン放射によるエネルギー損失が支配的✓ddEE//ddxx  測定→物性やJJeett  TToommooggrraapphhyy, multiply by powers of ! c # 0.2 GeV fm (other useful equalities:
1 GeV−2 = 0.389 mb).
tron-, Čerenkov- and transition-radiation energy losses can take place
rticle interacts with the medium magnetic field, if its velocity is greater
velocity of light, or if it crosses suddenly from one medium to another.
lities may lead to energy losses. Yet, those effects – studied e.g. in [11,plasmas – are generally less important in terms of the amount of Eloss .
gy of the particle is similar to the plasma temperature, E ∼ O(T ), then energy while traversing it.
ion is not so clear-cut since the diagrams assume well-defined asymphe outgoing particles may still be in the medium and further rescatter.

• QGPの物性研究にジェット（高エネルギーパートン）は大変有効なプローブ

OBOG会 (2013.9.28)

13

筑波大GGの戦略；

粒子識別n index = 1.012
n pe ≈ 20

σ TOF ≤ 100ps

385cm
200cm

€

€

200cm

Preliminarye+ PHENIXπ++
KProtonp
Ke-

OBOG会 (2013.9.28)

π-

14

TTOOFF  CCoonnssttrruuccttiioonn  aatt  TTssuukkuubbaa  

((11999966--11999988))

OBOG会 (2013.9.28)

15

TTOOFF  CCoonnssttrruuccttiioonn  aatt  BBNNLL  

((11999988--11999999))

OBOG会 (2013.9.28)

16

TTOOFF  IInnssttaallllaattiioonn  iinn  PPHHEENNIIXX  

((AAuugguusstt  11999999))

t0 counter

OBOG会 (2013.9.28)

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AAeerrooggeell  CCoonnssttrruuccttiioonn  &&  IInnssttaallllaattiioonn

OBOG会 (2013.9.28)

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(anti-) Proton /π Ratio((22))  SSuurrpprriissee!!  ((BBaarryyoonn  AAnnoommaallyy))
PHENIX: PRL 91, 172301 (2003), PRC 69, 034909 (2004)

CentralPeripheral

中條達也氏（筑波大）が原子核談話会新人賞受賞！

✓ 他の高エネルギー粒子衝突反応に比べて、多くの陽子や反陽子が生成されることを発見！
• 全く異なるハドロン生成メカニズム➡ 中條達也氏（現筑波大・講師）；原子核談話会新人賞受賞
三明＠原子核物理特論19

クォーク融合反応((QQuuaarrkk  CCooaalleesscceennccee))✓QGP特有のハドロン生成
メカニズム？

ハドロン

中間子の運動量分布(2q)；

W M ( pt ) ≈ CM ⋅ w 2 ( pt 2 )陽子の運動量分布(3q)；

W B ( pt ) ≈ CB ⋅ w 3 ( pt )3€w(pt)；

QGP
三明＠原子核物理特論

ユニバーサルな
€
クォークの
運動量分布
｛急激な減少を示す分布形｝
20

（２）方位角異方性
PyR
pl eacan tio
e n

Z

Pz

変換
Px

座標空間
Y
X

運動量空間

p2y p2xv2 = ⇥ 2⇤2
py + px

y 2 x2⇤
ecc = ⇥ 22
y +x
hhyyddrrooddyynnaammiiccss  !!

/R

0

λ

/R

0 と共に変換効率が高く流体力学に近づく

OBOG会 (2013.9.28)

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大きな方位角異方性  vv22

方位角異方性/クォーク数

PHENIX PRL 98(2007)162301
Au+Au 200 GeV

横運動エネルギー/クォーク数✓大きな楕円的方位角異方性  ((vv22))  の観測
➡ 極めて早い  tthheerrmmaalliizzaattiioonn〜  00..66  ffmm//cc  
➡ 完全流体!!  →強結合  QQGGPP  の発見

✓クォーク数  ((nnqq))  スケーリング
OBOG会 (2013.9.28)• →  uunniivveerrssaallな分布、  パートンレベルで異方性が決定

22

クォーク数((nn))スケーリング

クォークの統計
力学的分布✓クォーク融合反応の証拠• Universal quark distribution
中間子の運動量分布(2q)；dN M∝ w 2 = (1+ 2v 2,q cos2φ ) 2dφ≈ (1+ 4v 2,q cos2φ )陽子の運動量分布(3q)；€dN B∝ w 3 = (1+ 2v 2,q cos2φ ) 3dφ≈ (1+ 6v 2,q cos2φ )w；クォークの方位角分布€
OBOG会 (2013.9.28)

w ∝ (1+ 2v 2,q cos2φ )
23

0.3

vn

0.2

0.15
0.1

0.05
0

-4

-2

0

2

y

4

0.3

vn

0.15

2

2.5

3

PHENIX v2
PHENIX v3
PHENIX v4

0.1
0.05
0
0

0.3
0.25
0.2

uctuations (parts per million variations in temperature) as
iment (left) compared to seed fluctuations (corresponding
lated heavy ion collisions at RHIC (right). The measured
m fluctuations at the earliest moments of the explosion (bigaterial properties of the rippling fluid that ensues. Obserollisions reveal different and complementary properties ofcroseconds old universe.

0.05

ted States at RHIC, and it was there that we first
discovery was the top physics story across all areas✓ RRHHIICCにおける方位角異方性

OBOG会 (2013.9.28)

1.5

4
5

0.2

0.1

0

1

v2 20-30%
v3 20-30%

solid: a=0.115 fm
dashed: a=0.2 fm0.15

ics are substantially more affected by the system’s shear
viscosity than v2 and hence are a much more sensitive
probe of η/s. This behavior is expected because diffusive processes smear out finer structures corresponding
to higher n more efficiently than larger scale structures,and has been pointed out previously in [18].
So far all results were obtained using initial conditions
with a Gaussian width σ0 = 0.4 fm. We now study theeffect of the initial state granularity on the flow harmonics by varying σ0 . Decreasing σ0 causes finer structures
to appear and hence strengthens the effect of hot spots.
This results in a hardening of the spectra as previously
demonstrated in [17]. Because we want to compare to experimental data, we readjust the slopes to match the experimental pT -spectra by modifying the freeze-out temperature (see Table I).
Fig. 9 shows the dependence of vn (pT ) on the value of
σ0 , which we vary from 0.2 fm to 0.8 fm. While v2 isalmost independent of σ0 , higher flow harmonics show avery strong dependence. In Fig. 10 we present the dependence of the pT -integrated vn on the initial state granuT
larity characterized by σ0 .
Higher flow harmonics turn out to be a more sensitive probe of initial state granularity than v2 . While weare not yet attempting an exact extraction of η/s using
higher flow harmonics, our results give a first quantitative overview of the effects of both the initial state granularity and η/s on all higher flow harmonics up to v5 .
Comparing Figs. 7 and 9, we see that v4 (pT ) obtained
0from simulations
using η/s = 0.16 is about a factor of 2
below the experimental result, and that decreasing σ0 by
a factor of two does not increase it nearly as much. Notethat σ0 = 0.2 fm is already a very small value given that
we assign this width to a wounded nucleon. It is hence
unlikely that a higher initial state granularity will be able
to compensate for the large effect of the shear viscosity.

0

0.5

で合う！
/s = 0.08η/s=0.08
20-30% central 0.25 vv 20-30%
20-30%

vv
v4v5

FIG. 6. (Color online) Positive pion average pT as a functionof rapidity y for 20-30%
central Au+Au collisions from ideal2
and viscous (η/s = 0.08) including resonances up to the φ3
meson.

0.2

0pT [GeV]
BB..SScchheennkkee,,  aarrXXiivv::11110099..66228899

0.5

1h+/- dN/dηp

0.3

0.25

19

v2 20-30%
v3 20-30%
v4 20-30%
v5 20-30%
PHENIX v2
PHENIX v3
PHENIX v4

0.25

高次の方位角異方性

重イオン衝突の揺らぎ→HHiigghheerr  HHaarrmmoonniiccss

diat
mom
!pT "

was shown in [1] that v4 is very sensitive to the lattice
0.7
ideal
spacing if0.65itη/s=0.08
is not chosen small enough. Fig.η/s=0
4 shows
0.6 η/s=0.08 no δfvn (pT ) for
two different lattice spacings, our standard
0.55
value of a 0.5= 0.115 fm and a largerHigher
a = 0.2 fm. Differences
0.45
are within
the statistical error bars from averaging over
0.4
Harmonics
0.35 each.
100 events
π+ 〈pT〉 [GeV]rom quark-gluon plasma is likely to be the earliest
ever be re-enacted in the laboratory. Each nuclear
uon plasma, exploding in a "little bang" which recotons and neutrons were formed. These experimental nuclear force, as described via the theory of
ts is challenging due to the short lifetime and smallof billions of little bangs to study as well as a surditions.

0.15

0.5

1

1.5
pT [GeV]v2 20-30%
v3 20-30%
v4 20-30%
v5 20-30%
PHENIX v2
PHENIX v3
PHENIX v4

2

2.5

3

η/s=0.16

0.1
0.05

1.5
2
0
0
0.5
p [GeV]

2.5
1

3

1.5
pT [GeV]

2

2.5

3

FIG. 7. (Color online) pT -differential v2 to v5 from ideal hydrodynamics (left), viscous hydrodynamics with η/s = 0.08
(middle), and η/s = 0.16 (right). Results are averaged over
200 events each. Experimental data from PHENIX [58].

FIG
cent
reson

FIG. 4. →(Coloronline) Charged hadron v（  最小  !!!!  ）2 to v5 for η/s =比ずれ粘性  ((η//ss))  ~~  00..11
0.08 and σ = 0.4 fm as a function oftransverse
Similararguments hold for momentumv (p ).
→
ストリング理論における量子リミット  ((11//44π))！
•A
detailed
systematic
analysisof differentpT averaged over 100 single events thefor
lattice spacingsa models= forIn
initial state with a sophisticated description of fluctuations
isneededto
makemore
precisestatementson
0.115 ✓
fm  高次異方性の測定により重イオン衝突の初期条件(solid lines) and a = 0.2 fm the(dashedlines).
value of η/s. It is however clear from the present shea
3T

analysis that the utilization of higher flow harmonics canconstrain models for the initial state and values of trans- 200に制限がかけられるようになってきた（ee..gg..カラー
imen
グラス凝縮  ((CCGGCC))  など）..
Because we are presenting the first (3+1)-dimensional 24 usin

SSoopphhiissttiiccaatteedd  HHBBTT  AAnnaallyyssiiss
新井田貴文氏φpair

Ψ3

Ψ2R2µ [fm2]

25

20

20

15

15

0

2 15

10

side
out

-2

0

2

10

-2

0

2

φ - Ψ [rad]23✓横運動量依存性-20✓HHBBTTの運動量３DD解析
TT..  NNiiiiddaa,,  JJPPSS,,  MMaarrcchh  2299,,22001133

25➡CCeennttrraalliittyy  依存性

➡kktt依存性

Au+Au 200GeV π+π++π- π0-10%-215 30-60%✓衝突度を各事象で決定

φpair

2

φ - Ψ3 [rad]RRoouutt  ;;  FFllooww  により小さく
FIG. 2: (Color online) The azimuthal dependence of Rs and(2013.9.28)
ROBOG会for charged
pions with respect to 2nd - and 3rd -order event➡RRssiiddee、RRoouuttを測定✓ψ22（反応平面）、ψ３を各事象で決定➡（φーψnn）依存性• 時空発展の様子➡RRssiiddeeは幾何学的形状を主に反映➡RRoouuttはoouuttwwaarrdd  fflloowwとlliiffee  ttiimmee

25

QQGGPP生成の
主な証拠と
主要論文
((RRHHIICC--PPHHEENNIIXX))★ PPHHEENNIIXX  実験レビュー論文  ((NNuuccll..  PPhhyyss..  AA775577,,  118844--228833,,  ((22000033))))::  引用数  11447788..
•･

熱光子の観測（秋葉,,  PPRRLL  110044  ((22001100))  113322330011,,  引用数  118888）←超高温物質•･

JJ//ψ  抑制（郡司,,  PPRRLL  9988  ((22000077))  223322330011,,  引用数  334488）  ←カラー遮蔽•･

高横運動量ハドロン抑制（大山,,  PPRRLL  8888  ((22000022))  002222330011,,  引用数  669900）  ←ジェット抑制•･

大きな方位角異方性、クォーク数スケーリング（江角,,  PPRRLL  9911  ((22000033))  118822330011,,  引用数  
449911）  ←強結合QQGGPP、クォーク再結合•･

バリオン生成異常（中條,,  PPRRCC  6699  ((22000044))  003344990099,,  引用数  555522）  ←クォーク再結合•･

重クォーク抑制と方位角異方性（坂井,,  PPRRLL  9988  ((22000077))  117722330011,,  引用数  441188）  ←熱平衡
* 引用数は SPIRES における2013.2.7 現在のもの。名前は日本人で論文作成に主に関わったもの

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RRHHIICC  vvss  LLHHCC

RRHHIICCLLHHCC√  ssNNNN  ((GGeeVV))

22000055550000

TT//TTcc

11..9933..00--44..22

ε((GGeeVV//ffmm33))

55

1155--6600

τQQGGPP  ((ffmm//cc))

22--44>>1100✓HHoommee  wwoorrkk  ttoo  tthhee  LLHHCC,,  pphhyyssiiccss  ooff  jjeett  qquueenncchh➡  LLHHCC  hhaass  ssuuppeerriioorr  aaddvvaannttaaggee  iinn  hhaarrdd  pprroobbeess
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LLHHCC加速器による重イオン衝突（２０１０--）と初期成果✓初期温度、  RRHHIICC  の  11..44  倍を達成..  
✓大きな集団膨張、方位角異方性を確認✓大きなジェット抑制の観測✓励起Υ状態の消滅（高温状態生成の証拠）

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初期条件→前平衡→パートン散乱→熱化(QGP)→ハドロン生成→膨張✓ 衝突初期条件の解明（カラーグラス凝縮？）✓ Thermalizationのメカニズム✓ QGP物性量(比粘性、輸送係数等)の温度依存性✓ 相図の構造-- QQCCDD  ccrriittiiccaall  ppooiinntt  の探査  ((RRHHIICC))

鍵となる測定量：(1) ジェット (high pT)

η/s / (1/4π)

今後1100年間の展開

比ずれ粘性 : η/s/(1/4π)

The Physics Case for sPHENIX

What

String Theory Bound (KSS)pQCD (AMY)hydro+IQCD
Hadron Gas
Lattice QCD (gluodynamics)
semi-QGPQPM (finite µ )BHydro Fit (Niemi et al.)Hydro Fit (Song - a)Hydro Fit (Song - b)

40
35
30
25
20
15
10
5
0
0

KSS Bound
0.5

1

1.5

2

2.5

3
3.5
4
Temperature (T/Tc)

Figure 1.5: (Left) Shear 温度
Viscosity
divided(T/Tc) by econjectured KSS bound as a function of the redu
lations for the quark-gluon plasma case. See tex
LHC Experiments
conjectured scenarios for the quark-gluon plasm
Full-energy RHIC experimentsbound (as a near perfect fluid) to the weakly cou

more perfect at LHC energy.”

Shown in Figure 1.5 (right panel) are three p
modification of the medium from the strong t
the most rapid change in /s( T ) following th
III has the least rapid change going through t
imperative to map out this region in the ‘cond
the underlying reason for the change.

The above discussion has focused on /s as thquark-gluon plasma. However, both /s andto quark）
the underlying coupling of the ma(2) より高次の異方性（ 種々のハドロン、フォトン、light quark,sensitive
heavy
example the behavior of q̂ around the critical
te29
OBOG会 (2013.9.28)

ジェット測定で分かるQQGGPP物性
5-1C$+(&/8%&V%4$A#&✓ LLHHCC  エネルギー：•   RRHHIICC  に比べてハードプロセスが支配的✓   ジェットを基軸とした新たな観測量：•

  ジェット通過によるQQGGPP媒質応答•

  重クォークジェット、ジェット対、光子--ジェット•

  失ったエネルギーの再分配、EEOOSS、音速•

  重いクォークの強結合系QQGGPPとの相互作用（熱化、相互作用の強さ）✓ → データ読み出し高速化が必要✓ RRHHIICC  エネルギー：_8%+&41%.&/8%&./-1+()0&<1AI)%4&CA)9&D)1S%-&#1#%+/-"+.$61+&/1&"&G%"9)0&<1AI)%4&I-1C%&D=$(=%-&#1#%+/• 既存の装置はジェット測定に特化されてなく、収量や精度の点で、ジェットの直接測定が困難•   22  πカロリメータを設置..  HHiigghh  ppTT  化を図り、RRHHIICC  
エネルギーでのジェット測定が可能に• →ジェットエネルギー損失の温度依存性
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高次異方性 (higher harmonics)で分かる
QGP物性
FFlluuccttuuaattiioonnss  ooff  tthhee  UUnniivveerrssee

FFlluuccttuuaattiioonnss  ooff  LLiittttllee  bbaanngg

AALLIICCEE,,  SSeepp,,22001111

Power spectrum

8th

WMAP
宇宙論パラメータの決定

重イオン衝突衝突初期条件, QGP物性量 (例； η/s)

レアプローブ（種々のハドロン、フォトン、lepton, light quark, heavy quark）の
高次異方性測定により、熱化メカニズム、 衝突初期条件、 QGP物性（粘性等）がわかる→ 測定装置の高速化と High-pT 化が鍵OBOG会 (2013.9.28)

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今後の計画
H26-H35. 国内研究拠点（筑波／東大／広島／理研／RCNP） 総額約30億円.
CERN-ALICE＋RHIC-PHENIX実験での新測定器建設・高度化・実験遂行

ALICE実験

PHENIX実験

ジェット測定とQQGGPPとの相互作用

AALLIICCEE実験測定器群
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高精度測定による衝突初期のエネルギー密度の空間揺らぎ

次世代PPHHEENNIIXX実験
測定器群

EEnneerrggyy  
ddeennssiittyy

まとめ“HHoollooggrraapphhyy  aanndd  ccoolllliiddiinngg  ggrraavviittaattiioonnaall  sshhoocckk  wwaavveess  iinn  aassyymmppttoottiiccaallllyy  AAddSS55”
PPRRLL110066,,002211660011((22001111))

E/µ4

TTiimmee µv←µz

QQGGPP生成に刺激され、ストリング理論の若い理論家が多く参入�✓ 高エネルギー重イオン衝突による高温高密度QCD物質の研究は、原子核物理分野における最も重要な研究
課題の一つ。

✓ この１０年で高温高密度QCD物質の研究が大きく進展した。
• QGP相生成の確認• クォークレベルの統計力学、流体力学✓ 今後10年、LHC-ALICE実験、及び RHIC-PHENIX実験の両加速器及び測定器両面において大きな改良時期を迎え、さらなる研究進展が期待。

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CCMM）

大学院生向�けのQQGGPPの教科書！

す
ま も）
え
買 語版
で 国
nn
oo 中
zz
aa く
mm
AA もな
ま
（

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