Experimental verification of the GDH sum rule: A survey including the extension of the GDH integral to virtual photons - INSPIRE

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Experimental verification of the GDH sum rule: A survey including the extension of the GDH integral to virtual photons

GDH

Collaboration

•

K. Helbing
(
- Erlangen - Nuremberg U.
)

for the collaboration.

Sep 15, 2003

13 pages

Part of Spin physics. Proceedings, 15th International Symposium, Spin 2002, Upton, USA, September 9-14, 2002., 33-45

Published in:

AIP Conf.Proc. 675 (2003) 1, 33-45

Contribution to:

15th International Spin Physics Symposium (SPIN 2002), 33-45

Published: Sep 15, 2003

DOI:

10.1063/1.1607114

Experiments:

MAINZ-GDH

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Abstract: (AIP)

Sum rules involving the spin structure of the nucleon like those due to Bjorken, Ellis and Jaffe and the one due to Gerasimov, Drell and Hearn offer the opportunity to study the structure of strong interactions. At long distance scales in the confinement regime the Gerasimov‐Drell‐Hearn (GDH) Sum Rule connects static properties of the nucleon like the anomalous magnetic moment κ and the nucleon mass m, with the spin dependent absorption of real photons with total cross sections σ3/2 and σ1/2: ∫ 0 ∞ dv v ( σ 3/2 (v) − σ 1/2 (v) ) = 2π 2 α m 2 ⋅ κ 2 (1) Hence the full spin‐dependent excitation spectrum of the nucleon is related to its static properties. The sum rule has not been investigated experimentally until recently. For the first time this fundamental sum rule is verified by the GDH‐Collaboration with circularly polarized real photons and longitudinally polarized nucleons at the two accelerators Elsa and Mami. The investigation of the response of the proton as well as of the neutron allows to perform an isospin decomposition. Data from the resonance region up to the onset of the Regge regime are shown. The “sum” on the left hand side of the GDH Sum Rule can be generalized to the case of virtual photons. This allows to establish a Q 2 dependency and to study the transition to the perturbative regime of QCD. This is the subject of several experiments e.g. at JLab for the resonance region and of the Hermes experiment at Desy for higher Q 2. Moreover, this paper covers the status of theory concerning the GDH Sum Rule, the different experimental approaches and the results for the absorption of real and virtual photons will be reviewed.

talk: Upton 2002/09/09

References(50)

Figures(0)

[1]

A Sum rule for magnetic moments and the damping of the nucleon magnetic moment in nuclei

S.B. Gerasimov
(
- Dubna, JINR
)

- Sov.J.Nucl.Phys. 2 (1966) 430-433,
- Yad.Fiz. 2 (1965) 598-602

[2]

S.D. Drell
,
A.C. Hearn

- Phys.Rev.Lett. 16 (1966) 906

[3]

M. Hosoda
,
K. Yamamoto

- Prog.Theor.Phys. 36 (1966) 425

[4]

C.K. Iddings

- Phys.Rev.B 138 (1965) 446

[5]

Scattering of light of very low frequency by systems of spin 1/2

F.E. Low
(
- Illinois U., Urbana
)

- Phys.Rev. 96 (1954) 1428-1432
•
DOI:
- 10.1103/PhysRev.96.1428

[6]

Scattering of low-energy photons by particles of spin 1/2

Murray Gell-Mann
(
- Chicago U.
)
,
M.L. Goldberger
(
- Chicago U.
)

- Phys.Rev. 96 (1954) 1433-1438
•
DOI:
- 10.1103/PhysRev.96.1433

[7]

Investigations on the foundation and possible modifications of the Gerasimov-Drell-Hearn sum rule

Ralf Pantforder
(
- Bonn U.
)

e-Print:
- hep-ph/9805434

[8]

The Gerasimov-Drell-Hearn sum rule and current algebras

- Phys.Lett.B 329 (1994) 514-518
•
e-Print:
- hep-ph/9403286
•
DOI:
- 10.1016/0370-2693(94)91097-9

[9]

The Gerasimov-Drell-Hearn sum rule and the infinite momentum limit

- Eur.Phys.J.C 1 (1998) 585-592
•
e-Print:
- hep-ph/9703368
•
DOI:
- 10.1007/s100520050107

[10]

S.M. Roy
,
V. Singh

- Phys.Rev.Lett. 21 (1968) 861

[11]

Gravitons and the Drell-Hearn-Gerasimov sum rule: Support for large extra dimensions?

Haim Goldberg
(
- Northeastern U.
)

- Phys.Lett.B 472 (2000) 280-286
•
e-Print:
- hep-ph/9904318
•
DOI:
- 10.1016/S0370-2693(99)01381-7

[12]

LOW-ENERGY THEOREMS, DISPERSION RELATIONS AND SUPERCONVERGENCE SUM RULES FOR COMPTON SCATTERING

- Phys.Rev. 165 (1968) 1594-1609
•
DOI:
- 10.1103/PhysRev.165.1594

[13]

First measurement of the Gerasimov-Drell-Hearn integral for Hydrogen from 200 to 800 MeV

GDH and
A2

Collaborations

•

J. Ahrens
(
- Mainz U., Inst. Phys.
)

et al.

- Phys.Rev.Lett. 87 (2001) 022003
•
e-Print:
- hep-ex/0105089
•
DOI:
- 10.1103/PhysRevLett.87.022003

[14]

Helicity dependence of gamma p --> N pi below 450-MeV and contribution to the Gerasimov-Drell-Hearn sum rule

GDH and
A2

Collaborations

•

J. Ahrens
(
- Mainz U.
)

et al.

- Phys.Rev.Lett. 84 (2000) 5950-5954
•
DOI:
- 10.1103/PhysRevLett.84.5950

[15]

The Helicity amplitudes A(1/2) and A(3/2) for the D(13)(1520) resonance obtained from the polarized-gamma polarized-p ---> p pi0 reaction

GDH and
A2

Collaborations

•

J. Ahrens

et al.

- Phys.Rev.Lett. 88 (2002) 232002
•
e-Print:
- hep-ex/0203006
•
DOI:
- 10.1103/PhysRevLett.88.232002

[16]

A new frozen-spin target for 4pi particle detection

et al.

- Nucl.Instrum.Meth.A 436 (1999) 430-442
•
DOI:
- 10.1016/S0168-9002(99)00383-6

[17]

The 50-kV inverted source of polarized electrons at ELSA

- AIP Conf.Proc. 570 (2001) 1, 961
•
DOI:
- 10.1063/1.1384233

[17]

The polarized electron beam at ELSA

M. Hoffmann
(
- Bonn U. and
- Erlangen - Nuremberg U., Theorie III
)
,
W. von Drachenfels
(
- Bonn U. and
- Erlangen - Nuremberg U., Theorie III
)
,
F. Frommberger
(
- Bonn U. and
- Erlangen - Nuremberg U., Theorie III
)
,
M. Gowin
(
- Bonn U. and
- Erlangen - Nuremberg U., Theorie III
)
,
K. Helbing
(
- Bonn U. and
- Erlangen - Nuremberg U., Theorie III
)

et al.

- AIP Conf.Proc. 570 (2001) 1, 756
•
DOI:
- 10.1063/1.1384159

[18]

The MAMI source of polarized electrons

K. Aulenbacher
(
- Mainz U., Inst. Phys.
)
,
C. Nachtigall
(
- Mainz U., Inst. Phys.
)
,
H.G. Andresen
(
- Mainz U., Inst. Phys.
)
,
J. Bermuth
(
- Mainz U., Inst. Phys.
)
,
T. Dombo
(
- Mainz U., Inst. Phys.
)

et al.

- Nucl.Instrum.Meth.A 391 (1997) 498-506
•
DOI:
- 10.1016/S0168-9002(97)00528-7

[19]

PhD thesis, Erlangen, 1996

B. Kiel

[20]

DAPHNE: A Large acceptance tracking detector for the study of photoreactions at intermediate-energies

et al.

- Nucl.Instrum.Meth.A 301 (1991) 473-481
•
DOI:
- 10.1016/0168-9002(91)90013-G

[21]

The GDH-detector

K. Helbing
(
- Erlangen - Nuremberg U.
)
,
G. Anton
(
- Erlangen - Nuremberg U.
)
,
T. Michel
(
- Erlangen - Nuremberg U.
)
,
T. Speckner
(
- Erlangen - Nuremberg U.
)
,
G. Zeitler
(
- Erlangen - Nuremberg U.
)

et al.

- Nucl.Instrum.Meth.A 484 (2002) 129-139
•
DOI:
- 10.1016/S0168-9002(01)01988-X

[22]

A Compact solid state detector for small angle particle tracking

S. Altieri
(
- Pavia U. and
- INFN, Pavia
)
,
O. Barnaba
(
- Pavia U.
)
,
A. Braghieri
(
- INFN, Pavia
)
,
M. Cambiaghi
(
- Pavia U. and
- INFN, Pavia
)
,
A. Lanza
(
- INFN, Pavia
)

et al.

- Nucl.Instrum.Meth.A 452 (2000) 185-191
•
e-Print:
- nucl-ex/9911001
•
DOI:
- 10.1016/S0168-9002(00)00421-6

[23]

diploma thesis, Erlangen, 1998

T. Speckner

[23]

diploma thesis, Erlangen, 1998

G. Zeitler

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