Dileptons and Photons at Collider Energies K. Dusling, C.H. Lee and I. Zahed. QM14
Jan 12, 2016
Dileptons and Photons at Collider Energies
K. Dusling, C.H. Lee and I. Zahed.
QM14
Outline
• Set up• Rates, • Evolution• Experiments
Formally
time
evolution rate
acceptance
Rates: Hadrons
Equilibrium averaging
)0(),()()(
41
21
604
2
2
2
2
23
2
4
JxJxexdqWq
m
q
m
qqd
dR xiqll
)0()()( with )(Im1
2),( *4
/
00
JxJTexdiqWqW
eqqW xiqFF
Tq
l+
l-
l+
l-
Chiral Reduction
i d4 x e iqx 0T*J (x)J(0)0 i
a
d d4 x e iqx ina (k)T*J (x)J(0) in
a (k)
is,I
dN d4 x e iqx N ins,I (k)T*J (x)J(0) N in
s,I (k)
1,2,3, …-Pi,
Resonance Gas
1,2,3-N l
l
,,,, 11 Ka
ia
d d4 x e iqx ina (k)T*J (x)J(0) in
a (k) + …
ll
N
N
,
,N ,N
is,I
dN d4 x e iqx N ins,I (k)T*J (x)J(0) N in
s,I (k) + …
l l
l l
,,
i d4 x e iqx 0T*J (x)J(0)0
Vector-Axial Mixing: κ
d3k n(k0)
(2 3)2k0 f2 W1
F (q,k)
W1F 12q2 ImV (q2)
6(k q)2 ImA[(k q)2]
8((k q)2 m2q2)ImV (q2) Re[R (k q)]
(q q)
ia
d d4 x e iqx ina (k)T*J (x)J(0) in
a (k)
Chiral Limit and zero-mtm pion:
)()(Im12)0,( 222
1 qqqqW AV
F
κ
VA-Mixing explicitly
Dey, Eletsky, Ioffe 96
Rates
Electric Conductivity:
Flavour Susceptibility:
Rates: sQGP
sQGP:
ImW11R
1
4NC eq
2
q
q
2 12Tq
lnn
n
l+
l-
l+
l-
ImW11R
1
4NC eq
2
q
q
2 s
A4
2 4 2
Tq
n 1 n n 1 n
Hansson and Zahed 91’
sQGP Rates
Evolution
Sample hydro evolution
Faster cooling x higher rates: same
V2 Flow @ 2.76 TeV
Dileptons: NA60, Phenix, Star
NA60 : dN/dη=140 95’
PHENIX: 07’
Only!
Beam Energy Scan: STAR 13’
Photons: WA90, PHENIX
WA98
0<qT (GeV) <4 0<qT (GeV)<0.8
PHENIX
RHIC1 RHIC2
V2 PHENIX
Achievements
1. EM “OK”*
2. LxR “restored”
3. QGP “visible”
4. V2 “low”
(* π<<ρ)
Na45: 95’
Na60:03’
Phenix: 07’
Star: 13’
Vector Spectral Function
PHENIX extrapolation: γ
PHENIX: M<<qv
1 15% Systematics!