A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov...

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A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency of data on the total photoabsorption cross section for the deuteron in the Δ region

description

Partial channels in below 500 MeV 1)Deuteron photodisintegration ; 2)Coherent photoproduction ; 3)Incoherent photoproduction ; 4)Incoherent photoproduction ; 5)Incoherent photoproduction

Transcript of A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov...

Page 1: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

A.I. L’vov,P.N. Lebedev Institute of Physics, Moscow, Russia

andM.I. Levchuk,

B.I. Stepanov Institute of Physics, Minsk, Belarus

On possible inconsistency of data on the total photoabsorption cross section for the

deuteron in the Δ region

Page 2: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

There are two measurements of the total photoabsorption cross section on the deuteron in the first resonance region:1) Armstrong T.A. et al. The total deuteron hadronic cross section

in the energy range 0.265–4.215 GeV, Nucl. Phys. B41, 445 (1972). (Daresbury, England)

2) MacCormick M. et al. Total photoabsorption cross sections for from 200 to 800 MeV, Phys. Rev. C53, 41 (1996). (Mainz, Germany)

PDG2014

1 2 3H, H, and He

Page 3: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

Partial channels in below 500 MeV

1) Deuteron photodisintegration ;2) Coherent photoproduction ;3) Incoherent photoproduction ; 4) Incoherent photoproduction ; 5) Incoherent photoproduction

d X

d pn 0 0d d 0 0d pn

d pp .d nn

Page 4: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

Armstrong T.A. et al. Nucl. Phys. B41, 445 (1972)

Page 5: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

Summing over five channels1) Deuteron photodisintegration.There is rich experimental information on this channel. We take the total cross section from experiments with tagged photons only and fit them using the following formula

Data are from Arends J. et al., Nucl. Phys. A412, 509 (1984) (○);Crawford R. et al., Nucl. Phys. A603, 303 (1996) (●);Blanpied G. et al., Phys. Rev. C61, 024604 (1999) (□).

2 3 41 2

6 5

( )1 ( )

Cd pn

C CC eC C

Page 6: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

2) Coherent photoproduction . .There are data from MainzKrusche B. et al., Eur. Phys. J. A6, 309 (1999) (□);Siodlaczek U. et al, Eur. Phys. J. A10, 365 (2001) (●).We fit them using the following formula

0 0d d

0

2 31 2 3 4

26 5

( )1 ( )d d

D D D DD D

Page 7: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

3) Incoherent photoproduction .There are data from Mainz obtained in the same experimentsKrusche B. et al., Eur. Phys. J. A6, 309 (1999) (○);Siodlaczek U. et al, Eur. Phys. J. A10, 365 (2001) (●).We fit them using the same formula

0 0d pn

0

2 31 2 3 4

26 5

( )1 ( )d pn

D D D DD D

Page 8: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

4) Incoherent photoproduction .There are data from Benz P. et al, Nucl. Phys. B65, 158 (1973) (∎);Chiefari G. et al. Lett. Nuovo Cim. 13, 129 (1975) (Δ); Asai M. et al, Phys. Rev. C42, 837 (1990) (□).

We also use our modelL.M. et al. Phys. Rev. C74, 014004 (2006);L.M. Phys. Rev. C82, 044002 (2010).

d pp

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5) Incoherent photoproduction .There are no data on this reaction.

d nn

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Final results

Armstrong T.A. et al. Nucl. Phys. B41, 445 (1972) ();MacCormick M. et al. Phys. Rev. C53, 41 (1996) ().

Page 11: A.I. L’vov, P.N. Lebedev Institute of Physics, Moscow, Russia and M.I. Levchuk, B.I. Stepanov Institute of Physics, Minsk, Belarus On possible inconsistency.

A consequence for the Baldin sum rule

An assumption

is not quite true.One should use the following integral equation

where

2 2

( ).

2th

N XN N d

n d p

ˆ( ) [ ( ) ( )] ( ),d p n pnF eff

effˆ ( ) ( ) ( ) .N z N zF W p d p

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Babusci D. et al. Phys. Rev. C57, 291 (1998)

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L’vov A.I. & L.M. Nucl. Phys. A674, 449 (2000)

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Thank you for your attention!