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pdn, ωn, K + - , K 0 reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10, 2009

pd n, ωn, K + -, K 0 reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

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Page 1: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

pdn, ωn, K+-, K0 reactions at PANDA facility

Yu. Rogov, First seminar of FRRC Fellows

FAIR – Russia Research Center,

Moscow June, 9 - 10, 2009

Page 2: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

OZI rule*

NN→φπ is forbidden, NN→ωπ is allowed• φ production is possible only via mixing,

because φ and ω are mixture of ω0 and ω8: = cos 8 - sin 0

= sin 8 + cos 0

*Okubo S. // Phys. Rev. 1977. V.16. P.2336

0)()(

)(2

ddCBAMuuCBAM

ssCBAMZ

)(3

10 ssdduu

)2(6

18 ssdduu

Page 3: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

OZI rule

• Introducing ideal mixing angle Θi, cosΘi=(2/3)1/2, sinΘi=(1/3)1/2, Θi=35.5°

• Θ(mφ,mω,mω8), mω8=m(K*,ρ), Θ=39°

• If Z=0, then

• R(φ/ω)=tan2(Θ-Θi)f = 4.2·10-3

)cos()sin()(2

1 ii ssdduu

)tan()(

)(iCBAM

CBAM

Page 4: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

OZI rule

• Okubo: production of ss states in the non-strange hadrons interactions is forbidden

• - production in pp (pp) interaction is possible either due to admixture of light quarks in the wave function or due to strange quarks admixture in the nucleon.

0)()(

)(2

ddCBAMuuCBAM

ssCBAMZ

32 102.4)(tan)(

)(

iCBA

CBA

)cos()sin()(2

1 ii ssdduu

= -i =3.70

Page 5: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

OZI rule predicitions

32 104)(tan)(

)(

iCBA

CBA

• Universal, does not depend on energy or other properties of the initial state.

• Depends on the masses of the meson in the nonet

3

2

2 1016))1270((

))1525((

fCBA

fCBA

25.1)(

)(

CBA

CBA

Page 6: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

Comparison with experiment

R(/)=tg2(-I)=4.2 10-3

Weighted average of all experimental data

N

R(/)=(3.300.34)10-3

• NN

R(/)=(12.780.34)10-

3

NN

R(/)=(14.551.92)10-

3

Page 7: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

The OZI rule is always correct, its violation is only apparent

Violation indicates on non-trivial physics:

• Strange degrees of freedom in the nucleon

• Role of gluon degrees of freedom

Page 8: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

About hydrogen target

• Proton annihilation at rest• Slow antiproton capture on an orbit of

ppbar atom with large principal quantum number n~30.

• Low pressure gas (~mbar): cascade to lower level, annihilation from P levels with n=2

• Liquid H: Stark mixing between various angular momentum states, annihilation from large n and L=0, i.e. S states.

Page 9: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

• Crystal Barrel, 1995, LQ hydrogen targetp + p → + p + p → +

• R() = (29497) 10-3

• R()OZI = 4.2 10-3

• L=0, S=0 1S0 spin singlet

Page 10: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

• OBELIX, 1995, LQ, NTP, 5 mbp + p → + p + p → +

• R() = (11410) 10-3

• R()OZI = 4.2 10-3

• L=0, S=1 3S1

• spin triplet

Page 11: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

• Different situation for annihilation from S- and P-waves

• R() = (12012) 10-

3 3S1

• R() < 7.2 10-3 1 P1

• spin triplet – enhanced• spin singlet – suppressed

Page 12: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

f2’(1525)/f2(1270)

• Tensor mesons:

L=1, S=1, J=2

f2(1270) normal qq

f2’ (1525) ss

• R(f2’f2) = (4714) 10-3 3S1

• R(f2’f2) = (14920) 10-3 1

P1

• spin triplet – suppressed• spin singlet – enhanced

Page 13: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

• OBELIX, 1995, NTP,

5 mb p + p → + + + -

p + p → + + + -

For all events:• R() = (5-6) 10-3

• R()OZI = 4.2 10-3

For events with M=300-500 MeV

• R() = (16-30) 10-

3

Page 14: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

nn

• OBELIX, Crystal Barrelp + d → + np + d → + nB.Pontecorvo, 1956One-meson annihilation• R() = (15629)

10-3

• R()OZI = 4.2 10-3

Page 15: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

/

p

p

s

s

s

s

pp

• If it were a normal quark reaction

()exp ~ 4 b• why is it so large?() was not

measured

nbtg i 10)()()( 4

Page 16: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

At LEAR experiemts

Strong violation of the OZI rule was found in

pp pp, pp (3S1)

pdn

Does it depend on – spin– orbital angular

momentum– momentum transfer– isospin?

Page 17: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

Pontecorvo reactions

• Largest momentum transfer:q2=-0.782 GeV2/c2 inpdn, compared toq2=-0.360 GeV2/c2 inpp0

• Interesting physics*:two-step modelpp0, nnR() = (15629) 10-3

Rth() = (9227) 10-3

R() decreases with energy

*Kondratyuk L.A., Sapozhnikov M.G., Phys.Lett., 1989, B220, 333.

*Kondratyuk L.A. et al., Yad.Fiz., 1998, 61, 1670.

Page 18: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

Pontecorvo reactions

• Reactions p + d+K0, 0+K0

R=Y(K)/Y(K) = 0.920.15two-step model R=0.012 because σ(KNX) > σ(KN X)

• Is two-step model correct?

Page 19: pd  n, ωn, K +  -, K 0  reactions at PANDA facility Yu. Rogov, First seminar of FRRC Fellows FAIR – Russia Research Center, Moscow June, 9 - 10,

Pontecorvo reactions at PANDA

• Energy region never measured before

• High statistics expected

• Noone really knows why OZI rule is violated in such selective manner

• Assuming that OZI rule is precisely correct, we have a hint to non-trivial physics