Investigation of the conjectured nucleon deformation at low momentum transfer

Sparveris, N.F.; Alarcon, R.; Bernstein, A.M.; Bertozzi, W.; Botto, T.; Bourgeois, P.; Calarco, J.; Casagrande, F.; Distler, M.O.; Dow, K.

doi:10.1103/PhysRevLett.94.022003

Investigation of the conjectured nucleon deformation at low momentum transfer

OOPS

Collaboration

•

N.F. Sparveris
(
- IASA, Athens and
- Athens U.
)

Aug, 2004

4 pages

Published in:

Phys.Rev.Lett. 94 (2005) 022003

e-Print:

nucl-ex/0408003 [nucl-ex]

DOI:

10.1103/PhysRevLett.94.022003

Experiments:

BATES-OOPS

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Abstract:

We report new precise H

(e,e^\prime p)\pi^0

measurements at the

\Delta(1232)

resonance at

Q^2= 0.127

(GeV/c)

^2

using the MIT/Bates out-of-plane scattering (OOPS) facility. The data reported here are particularly sensitive to the transverse electric amplitude (

E2

) of the

\gamma^* N\to\Delta

transition. Analyzed together with previous data yield precise quadrupole to dipole amplitude ratios

EMR = (-2.3 \pm 0.3_{stat+sys} \pm 0.6_{model})%

and

CMR = (-6.1 \pm 0.2_{stat+sys}\pm 0.5_{model})%

and for

M^{3/2}_{1+} = (41.4 \pm 0.3_{stat+sys}\pm 0.4_{model})(10^{-3}/m_{\pi^+})

. They give credence to the conjecture of deformation in hadronic systems favoring, at low

Q^2

, the dominance of mesonic effects.

13.60.Le
13.40.Gp
14.20.Gk
electron-nucleus reactions
photon-nucleon interactions
Delta baryons

References(26)

Figures(0)

The unmellisonant quark

Sheldon L. Glashow
(
- Harvard U.
)

- Physica A 96 (1979) 1-2, 27-30
•
DOI:
- 10.1016/0378-4371(79)90192-4

Determination of the E2 / M1 ratio in the gamma N ---> Delta (1232) transition from a simultaneous measurement of p(polarized gamma, p) pi0 and p(polarized gamma, pi+)n

R. Beck
(
- Mainz U., Inst. Kernphys.
)
,
H.P. Krahn
(
- Mainz U., Inst. Kernphys.
)
,
J. Ahrens
(
- Mainz U., Inst. Kernphys.
)
,
J.R.M. Annand
(
- Glasgow U.
)
,
H.J. Arends
(
- Mainz U., Inst. Kernphys.
)

et al.

- Phys.Rev.C 61 (2000) 035204
•
e-Print:
- nucl-ex/9908017
•
DOI:
- 10.1103/PhysRevC.61.035204

N --> Delta Transition from Simultaneous Measurements of p (gamma -->, pi) and p (gamma -->, gamma)

et al.

- Phys.Rev.Lett. 79 (1997) 4337-4340
•
DOI:
- 10.1103/PhysRevLett.79.4337

Measurement of the beam helicity asymmetry in the p(polarized-e, e-prime p) pi0 reaction at the energy of the Delta(1232) resonance

et al.

- Phys.Rev.Lett. 88 (2002) 142001
•
e-Print:
- nucl-ex/0112009
•
DOI:
- 10.1103/PhysRevLett.88.142001

Q**2 dependence of quadrupole strength in the gamma* p ---> Delta+(1232) ---> p pi0 transition

CLAS

Collaboration

•

K. Joo

et al.

- Phys.Rev.Lett. 88 (2002) 122001
•
e-Print:
- hep-ex/0110007
•
DOI:
- 10.1103/PhysRevLett.88.122001

Electroproduction of the Delta (1232) resonance at high momentum transfer

V.V. Frolov
(
- Rensselaer Poly.
)
,
G.S. Adams
(
- Rensselaer Poly.
)
,
A. Ahmidouch
(
- Kent State U.
)
,
C.S. Armstrong
(
- William-Mary Coll.
)
,
K. Assamagan
(
- Hampton U.
)

et al.

- Phys.Rev.Lett. 82 (1999) 45-48
•
e-Print:
- hep-ex/9808024
•
DOI:
- 10.1103/PhysRevLett.82.45

Measurement of the recoil polarization in the p (polarized e, e-prime polarized p) pi0 reaction at the Delta(1232) resonance

et al.

- Phys.Rev.Lett. 86 (2001) 2959-2962
•
e-Print:
- nucl-ex/0010020
•
DOI:
- 10.1103/PhysRevLett.86.2959

Search for quadrupole strength in the electroexcitation of the delta(1232)

C. Mertz
(
- Arizona State U. and
- Athens U.
)
,
C. Vellidis
(
- Athens U.
)
,
R. Alarcon
(
- Arizona State U.
)
,
D.H. Barkhuff
(
- Virginia U.
)
,
A.M. Bernstein
(
- MIT, LNS and
- MIT, Bates Linear Accelerator
)

et al.

- Phys.Rev.Lett. 86 (2001) 2963-2966
•
e-Print:
- nucl-ex/9902012
•
DOI:
- 10.1103/PhysRevLett.86.2963

Measurement of the transverse longitudinal cross-sections in the p (polarized-e, e-prime p) pi0 reaction in the Delta region

MIT-Bates OOPS

Collaboration

•

C. Kunz
(
- MIT, LNS
)

et al.

- Phys.Lett.B 564 (2003) 21-26
•
e-Print:
- nucl-ex/0302018
•
DOI:
- 10.1016/S0370-2693(03)00675-0

Spin-dependent electron proton scattering in the Delta-excitation region

L.D. van Buuren
(
- Nikhef, Amsterdam and
- Vrije U., Amsterdam
)
,
D. Szczerba
(
- Zurich, ETH
)
,
R. Alarcon
(
- Arizona State U.
)
,
D.J. Boersma
(
- Nikhef, Amsterdam
)
,
J.F. J. van den Brand
(
- Nikhef, Amsterdam and
- Vrije U., Amsterdam
)

et al.

- Phys.Rev.Lett. 89 (2002) 012001
•
DOI:
- 10.1103/PhysRevLett.89.012001

Induced proton polarization for pi0 electroproduction at Q2 = 0.126-GeV2 / c**2 around the Delta (1232) resonance

M.I.T.-Bates OOPS and
FPP

Collaborations

•

G.A. Warren
(
- MIT and
- MIT, LNS and
- MIT, Bates Linear Accelerator
)

et al.

- Phys.Rev.C 58 (1998) 3722
•
e-Print:
- nucl-ex/9901004
•
DOI:
- 10.1103/PhysRevC.58.3722

Measurement of the R(LT) response function for pi0 electroproduction at Q2 = 0.070 (GeV/c)2 in the N ---> Delta transition

OOPS

Collaboration

•

N.F. Sparveris
(
- IASA, Athens and
- Athens U.
)

et al.

- Phys.Rev.C 67 (2003) 058201
•
e-Print:
- nucl-ex/0212022
•
DOI:
- 10.1103/PhysRevC.67.058201

Dynamical study of the Delta excitation in N (e, e-prime pi) reactions

T. Sato
(
- Osaka U. and
- Argonne, PHY
)
,
T.S.H. Lee
(
- Argonne, PHY
)

- Phys.Rev.C 63 (2001) 055201
•
e-Print:
- nucl-th/0010025
•
DOI:
- 10.1103/PhysRevC.63.055201

A Unitary isobar model for pion photoproduction and electroproduction on the proton up to 1-GeV

- Nucl.Phys.A 645 (1999) 145-174
•
e-Print:
- nucl-th/9807001
•
DOI:
- 10.1016/S0375-9474(98)00572-7

Pi0 photoproduction and electroproduction at threshold within a dynamical model

S.S. Kamalov
(
- Taiwan, Natl. Taiwan U.
)
,
Guan-Yeu Chen
(
- Taiwan, Natl. Taiwan U.
)
,
Shin-Nan Yang
(
- Taiwan, Natl. Taiwan U.
)
,
D. Drechsel
(
- Mainz U., Inst. Kernphys.
)
,
L. Tiator
(
- Mainz U., Inst. Kernphys.
)

- Phys.Lett.B 522 (2001) 27-36
•
e-Print:
- nucl-th/0107017
•
DOI:
- 10.1016/S0370-2693(01)01241-2

Pion cloud and the Q**2 dependence of gamma* N <---> Delta transition form-factors

- Phys.Rev.Lett. 83 (1999) 4494-4497
•
e-Print:
- nucl-th/9904072
•
DOI:
- 10.1103/PhysRevLett.83.4494

Threshold pion photoproduction on nucleons

D. Drechsel
(
- Mainz U., Inst. Phys.
)
,
L. Tiator
(
- Mainz U., Inst. Phys.
)

- J.Phys.G 18 (1992) 449-497
•
DOI:
- 10.1088/0954-3899/18/3/004

Multipole amplitudes of pion photoproduction on nucleons up to 2-Gev within dispersion relations and unitary isobar model

I.G. Aznauryan
(
- Yerevan Phys. Inst.
)

- Phys.Rev.C 67 (2003) 015209
•
e-Print:
- nucl-th/0206033
•
DOI:
- 10.1103/PhysRevC.67.015209

Analysis of pion photoproduction data

R.A. Arndt
(
- George Washington U.
)
,
W.J. Briscoe
(
- George Washington U.
)
,
I.I. Strakovsky
(
- George Washington U.
)
,
R.L. Workman
(
- George Washington U.
)

- Phys.Rev.C 66 (2002) 055213
•
e-Print:
- nucl-th/0205067
•
DOI:
- 10.1103/PhysRevC.66.055213

N to Delta electromagnetic transition form-factors from lattice QCD

C. Alexandrou
(
- Cyprus U.
)
,
Ph. de Forcrand
(
- Zurich, ETH and
- CERN
)
,
Th. Lippert
(
- Wuppertal U.
)
,
H. Neff
(
- IASA, Athens and
- Boston U.
)
,
John W. Negele
(
- MIT, LNS
)

et al.

- Phys.Rev.D 69 (2004) 114506
•
e-Print:
- hep-lat/0307018
•
DOI:
- 10.1103/PhysRevD.69.114506

Nucleon deformation

C.N. Papanicolas
(
- Athens U. and
- IASA, Athens
)

- Eur.Phys.J.A 18 (2003) 141-145
•
DOI:
- 10.1140/epja/i2002-10289-y

Deviation of the nucleon shape from spherical symmetry: Experimental status

A.M. Bernstein
(
- MIT, LNS
)

- Eur.Phys.J.A 17 (2003) 349-355
•
e-Print:
- hep-ex/0212032
•
DOI:
- 10.1140/epja/i2002-10176-7

Out-of-plane spectrometry: Why and how

C.N. Papanicolas
(
- Illinois U., Urbana
)
,
R. Alarcon
(
- Illinois U., Urbana
)
,
L.S. Cardman
(
- Illinois U., Urbana
)
,
S. Dolfini
(
- Illinois U., Urbana
)
,
R.M. Laszewski
(
- Illinois U., Urbana
)

et al.

- Nucl.Phys.A 497 (1989) 509C-518C
•
DOI:
- 10.1016/0375-9474(89)90495-8

Design of an 830-MeV/c out-of-plane spectrometer

S.M. Dolfini
(
- Illinois U., Urbana
)
,
R. Beck
(
- Illinois U., Urbana
)
,
L.S. Cardman
(
- Illinois U., Urbana
)
,
R.M. Laszewski
(
- Illinois U., Urbana
)
,
J.B. Mandeville
(
- Illinois U., Urbana
)

et al.

- Nucl.Instrum.Meth.A 344 (1994) 571-582
•
DOI:
- 10.1016/0168-9002(94)90877-X

Measured properties of an out-of-plane spectrometer

J.B. Mandeville
(
- Illinois U., Urbana
)
,
L.S. Cardman
(
- Illinois U., Urbana
)
,
S.M. Dolfini
(
- Illinois U., Urbana
)
,
W. Kim
(
- Illinois U., Urbana
)
,
R.M. Laszewski
(
- Illinois U., Urbana
)

et al.

- Nucl.Instrum.Meth.A 344 (1994) 583-591
•
DOI:
- 10.1016/0168-9002(94)90878-8

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