Transcript Document

CBCOS-2014
Wuhan
K* in Dense and Hot Matter
Pornrad Srisawad
Naresuan University, Phitsanulok, Thailand
In corporation with
A Ilner, D Cabrera and E Bratkovskaya
Contents
•
•
•
•
•
Introduction
Medium effects of K* in dense nuclear matter
Medium effects of K* in hot hadronic matter
Results
Conclusions
The properties of kaon close to threshold energy have investigate in HIC at SIS
Decay mode K*(892)
K *  K
K * /  K *   K  K 
loop self energy diagram.
Good probes for dense matter
Kaons:
K   us  : NN  N K 
Ethr  1.58 GeV
 N  K 
K   us  : NN  NNK  K 
Ethr  2.5 GeV
K + use for probe of EOS at high densities.
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Kaons change their properties in dense matter
in-medium energy”
   iV 2  m*2     0

K  K
 

mK*  mK2 

f
KN
2

 s  V V 
 k *2  mK*2  K   0
In-medium energy
  k  m  V0
*2
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*2
K
U   , k      , k   0  k 
 k 2  mK2 
 KN
2


V
s
0  V0
*2
f
 k 2  mK2
BR potential
UK  0  30 MeV
 KN  450 MeV
f*2  0.6 f2 ; f*2  f2
KL potential U K  0  5 MeV
 KN  350 MeV
f*2  f2
Density dependence of the in-medium kaon potential
at zero momentum.
[NPA 567 (1994) 937],
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Probing in-medium kaon potential
• Total yields
○: w/o pot
●: with pot
Influence of in-medium K+ potential on the kaon yields
for central (b=0) Au +Au and C + C reactions.
○: w/o pot
●: with pot
♦: KaoS data
The K+ excitation functions in Au + Au (scaled by 10-1) and
C + C reactions are compared to data from KaoS [PRL 82
(99) 1640); PRC 66 (02) 054604].
K+ rapidity distributions in Ni + Ni reactions at 1.93 AGeV.
Data are from FOPI [NPA625 (97) 307] and KaoS [PLB 495
(2000) 26].
♦: KaoS ▲: FOPI
Δ: QMD w/o pot; ▲: QMD with pot.
Experiment activity HADES (GSI) performing measure
hadronic resonances in medium properties.
We present in this study of spectral function of K* base on
chirally motivated models of the meson selfenegies
dependence on density.
AK *   ,  N   C1
 2 *K   ,  N 
2
*
   2  M *2    2   *   ,   2
N
N
K
K
*
*

C1 is normalization constant as  AK  M ,  N  dM
*
0
M K*2* is in medium meson mass
M is kaon energy
1
In-medium decay width
*K *  M ,  N    decay   coll

 
 decay   ,  N    0K *  0

42 MeV 

892 MeV





2
  m

q 3   , M  A  M ,  N  dM

q 3  0 , M  A  M , 0  dM
0
0  m
M min
in _ vacuum
   , M , M 
q  , M  
2
2
2
   , M , M     2   M  M      2   M  M   


A  M ,  N   2 M   M 2  M K2  0.13M K2   /  0  

is K* energy

A.Ilnera,D. Cabreraa,P. Srisawad,E. Bratkovskaya arXiv:1312.5215 [hep-ph]
Medium effects in hot hadronic matter
In framework of Chiral Perturbation Theory
Kaon collision width
Mass shift
M K*  M K   M K
Mean-field potential
Self energy of kaons at rest
Attractive mass shift up to T = 100-120 MeV
B.V. Martemyanov, et al Nucl.Phys.56 (2006)1
We present in this study of spectral function of K base on
chirally motivated models of the meson selfenegies
dependent on temperature .
Ai  M , T   C1
2
M 2 *i  M , T 
  M 2  M i*2 T  2   M *i  M , T  2
A.Ilnera,D. Cabreraa,P. Srisawad,E. Bratkovskaya arXiv:1312.5215 [hep-ph]
In-medium decay width of K* in hot matter
2
*K *
 
1
  K * ,dec   , T    0  0 
3
   q  0 , mK 
  m

dMA( M , T )q 3   , M  F 2  ,  , M 
0
Form factor of dipole form
  2  q 2 (M K * , M K 
F  ,  , M   

2
2


q
(

,
M)


2
3
q
  , mK  F 2 ,  , m



0
0
 vac



  K*   3

K 
K*

q

,
m
 0 K
 
2
  1.5  2.1GeV
Off –shell in-medium width of the K*
A.Ilnera,D. Cabreraa,P. Srisawad,E. Bratkovskaya arXiv:1312.5215 [hep-ph]
We present in this study of spectral function of K* within
a Breit –Wigner quasi-particle picture dependent on temperature .
AK *   , T   C1
2
 2 *i   , T 
   2  M i*2 T  2   *i   , T  2
A.Ilnera,D. Cabreraa,P. Srisawad,E. Bratkovskaya arXiv:1312.5215 [hep-ph]
Conclusion
Medium effects in dense matter
1. K* experiences a mild repulsive mass shift from nucleons.
of about 5 % of normal nuclear matter density.
2. Decay width of K* is barely modified by the properties of K in medium
3. The spectral function of K* maintains a single –peak structure,
which facilitates it treatment in microscopic transport model.
Medium effects in hot matter
1. The changes in the k* width are accompanied by a small repulsive mass shift
which we have calculated by means of a dispersion relation.
2. K* resonances are only mildly sensitive to the hadronic medium
in absence of baryons for the typical temperature range expected
in the hadronic phase of ta heavy ion collisions.
Aims to facilitate the analysis of in-medium properties of K* in HIC within transport model
Thank you
for
your attention