dileptons and photons at collider energies
DESCRIPTION
Dileptons and Photons at Collider Energies. K. Dusling , C.H. Lee and I . Zahed. QM14. Outline. Set up Rates, Evolution Experiments. Formally. acceptance. evolution. rate. time. Rates: Hadrons. Equilibrium averaging. l +. l +. l -. l -. Resonance Gas. + …. 1,2,3, …-Pi,. - PowerPoint PPT PresentationTRANSCRIPT
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!