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B. Ramstein,
C. Mosbacher,
T. Hennino,
W. Augustyniak,
D. Bachelier,
H.G. Bohlen,
J.L. Boyard,
R. Dahl,
C. Ellegaard, C. Gaarde, [......],
D. L'Hôte,
H.P. Morsch,
M. Österlund,
J. Poitou,
P. Radvanyi,
M. Roy-Stephan,
T. Sams,
M. Skousen,
S. Tarlé-Rousteau,
P. Zupranski
[show abstract]
[hide abstract]
ABSTRACT: The exclusive 2H( 3He, t)2p reaction has been studied at 2 GeV for energy transfers up to 500 MeV and triton angles up to 3.4°. The protons were measured in the large acceptance magnetic detector DIOGENE, in coincidence with the forward tritons detected
in a dedicated magnetic arm. The energy transfer spectra extend well above the pion threshold. However, in the region of Δ
excitation, the yield is less than 10% of the inclusive 2H( 3He, t) cross-section, which indicates the small contribution of the ΔN ↦ NN process. The angular distributions of the two
protons in their center of mass have been analysed as a function of energy transfer and triton angle and a Legendre polynomial
decomposition has been achieved. These data have been compared to a model based on a coupled-channel approach for describing
the NN and NΔ systems.
European Physical Journal A 01/2003; 16(4):583-597. · 2.19 Impact Factor
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L. V. Malinina,
G. D. Alkhazov,
W. Augustyniak,
M. Boivin,
J.-L. Boyard,
R. Dahl,
M. Drews,
C. Ellegaard,
L. Fahri, C. Gaarde, [......],
B. V. Razmyslovich,
M. Roy-Stephan,
I. M. Sitnik,
M. Skousen,
E. A. Strokovsky,
I. I. Tkach,
E. Tomasi-Gustafsson,
S. S. Volkov,
A. A. Zhdanov,
P. Zupranski
[show abstract]
[hide abstract]
ABSTRACT: A study of inelastic scattering of polarized 3.73-GeV/c deuterons on protons in the energy region of the Roper N(1440) and the Δ(1232) resonances excitation has been performed in an exclusive experiment at LNS (Laboratoire National SATURNE, Saclay, France) using the SPES4-π setup. Tensor and vector analyzing powers of pion production for the reactions: d+p⃗d+n+π+, d+p⃗d+p+π0, d+p⃗d+N+ππ have been measured as functions of the squared deuteron four-momentum transfer t, of the effective mass of the subsystems Nπ, Nππ, and of the pion emission angle. A strong dependence of these analyzing powers upon the pion emission angle is observed. It is found that Ayy values for the considered reaction channels are systematically larger than the known inclusive p(d,d′)X world data at the nearest beam energy.
Phys. Rev. C. 11/2001; 64(6).
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B. Ramstein,
C.A. Mosbacher,
D. Bachelier,
I. Berquist,
M. Boivin,
J.L. Boyard,
A. Brockstedt,
L. Carlén,
R. Dahl,
P. Ekström,
C. Ellegaard, C. Gaarde,
T. Hennino,
J.C. Jourdain,
C. Goodman,
J.S. Larsen,
P. Radvanyi,
M. Roy-Stephan
[show abstract]
[hide abstract]
ABSTRACT: The inclusive 2(3He,t) reaction has been studied at 2 GeV for energy transfers up to 500 MeV and scattering angles from 0.250 up to 40. Data are well reproduced by a model based on a coupled-channel approach for describing the NN and N( systems. The effect of final state interaction is important in the low energy part of the spectra. In the delta region, the cross-section is very sensitive to the effects of (-N interaction and (N M NN process. The latter has also a large influence well below the pion threshold. The calculation underestimates the experimental cross-section between the quasi-elastic and the delta peaks; this is possibly due to projectile excitation or purely mesonic exchange currents.
European Physical Journal A 09/1999; 6(2):225-233. · 2.19 Impact Factor
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T.N. Taddeucci,
W.P. Alford,
M. Barlett,
R.C. Byrd,
T.A. Carey,
D.E. Ciskowski,
C.C. Foster, C. Gaarde,
C.D. Goodman,
C.A. Goulding, [......],
D.J. Horen,
J. Larsen,
D. Marchlenski,
J.B. McClelland,
D. Prout,
J. Rapaport,
L.J. Rybarcyk,
W.C. Sailor,
E. Sugarbaker,
C.A. Jr. Whitten
[show abstract]
[hide abstract]
ABSTRACT: Differential-cross-section distributions for the {sup 7}Li({ital p},{ital n}){sup 7}Be(g.s.+0.43-MeV) reaction have been measured for {ital E}{sub {ital p}}=80, 120, 160, 200, 494, 644, and 795 MeV. These distributions have been integrated and normalized to independent values for the total cross section obtained from parametrizations of {sup 7}Li({ital p},{ital n}) activation measurements. Zero-degree cross sections obtained from this normalization are reported.
Physical Review, C (Nuclear Physics); (USA). 05/1990; 41:6.
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T. N. Taddeucci,
C. D. Goodman,
R. C. Byrd,
I. J. van Heerden,
T. A. Carey,
D. J. Horen,
J. S. Larsen, C. Gaarde,
J. Rapaport,
T. P. Welch,
E. Sugarbaker
[show abstract]
[hide abstract]
ABSTRACT: The transverse polarization transfer for the 90Zr(p,n)
reaction has been measured for Ep=160 MeV and theta=0°. A
sequence of alternating unnatural parity and natural parity excitations
is clearly revealed. Some of the observed features are consistent with
the known or predicted excitation energies of ΔL=0 and ΔL=1
resonances.
Physical Review C 01/1986; 33:746-748. · 3.31 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: Angular correlations have been measured between light particles emitted in compound nucleus decay for different nuclei formed in heavy ion reactions. The reactions used were 16O+27Al at Elab = 50 and 60 MeV, 16O+natCa and 16O+58Ni at 70 MeV. The αα, αp and pp correlations were measured in a plane perpendicular to the beam axis as a function of the relative azimuthal angle. The anisotropies wre around 5:1, 2:1 and 1.2:1 for the αα, αp and pp correlations respectively. Detailed calculations of the αα correlations in the geometry show that the correlation is sensitive to the angular momentum in the entrance channel. The yield for Δø = 180 primarily comes from the high angular momenta whereas the yield at Δø = 90° has contributions from all the angular momenta.
Nuclear Physics A. 316:189-204.
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[show abstract]
[hide abstract]
ABSTRACT: The 40Ca(p,n) reaction at Ep=159.3 MeV excites a state at Ex=2.7±0.1 MeV in 40Sc. The energy dependence and differential cross section angular distribution for this reaction indicate that this state is the Tz=-1 analog of a known 1+ state at Ex=10.32 MeV in 40Ca. We find that the Gamow-Teller strength for this 0+→1+ (p,n) transition is B(GT)=0.21±0.04. Comparison of B(GT) to B(M1)↑ for the analogous M1 transition in 40Ca indicates a substantial orbital-current contribution to the M1 strength. The 40Ca(p,n) reaction also strongly excites a 2- state at Ex=0.77 MeV in 40Sc. Good agreement is found between properly normalized distorted-wave impulse approximation calculations and the measured differential cross sections for this transition at 159.3 MeV.NUCLEAR REACTIONS 40Ca(p,n)40Sc, Ep=59.3, 118.3, 159.3 MeV, Ex=0.0, 0.77, 2.35, 2.7, 4.3 MeV, measured σ(θ), θ=0-24°, deduced B(GT) for 2.7 MeV state. 42Ca(p,n)42Sc(0.611 MeV), Ep=159.3 MeV, measured σ(θ), θ=0-20°.
Phys. Rev. C. 28(6).
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[show abstract]
[hide abstract]
ABSTRACT: Angular distributions for the ground-state (ΔJr=1+) and 0.96-MeV (ΔJπ=2+) transitions in the 12C(p,n)12N reaction have been measured at incident energies of 120, 160, and 200 MeV. The measured values of the differential cross section align themselves into smooth curves independent of incident energy when converted into plane-wave cross section values and plotted versus momentum transfer. This information supports the hypothesis that the spinisospin term of the effective interaction is almost energy independent in this energy region. Microscopic distortedwave impulse approximation calculations are presented.[NUCLEAR REACTIONS 12C(p,n)12N, E=120,160,200 MeV; measured neutron spectra at several angles between θ=0∘ and θ=30∘; extracted σ(E,θ) to g.s. and 0.96-MeV states of 12N. Compared angular distributions with microscopic calculations. Deduced plane-wave cross sections versus momentum transfer.]
Phys. Rev. C. 24(2).
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T. N. Taddeucci,
J. Rapaport,
D. E. Bainum,
C. D. Goodman,
C. C. Foster, C. Gaarde,
J. Larsen,
C. A. Goulding,
D. J. Horen,
T. Masterson,
E. Sugarbaker
[show abstract]
[hide abstract]
ABSTRACT: Information concerning the ratio of the isovector effective interaction strengths |Jστ/Jτ| may be obtained from the ratio of (p,n) Gamow-Teller and isobaric analog state 0° differential cross sections. We have examined 0° (p,n) data for the energy range 5-200 MeV and find that for energies larger than 50 MeV and for targets with A=7-42 the product of the interaction-strength and distortion-factor ratios |Jστ/Jτ|(Nστ/Nτ)1/2 appears to be mass independent and linear as a function of bombarding energy.NUCLEAR REACTIONS 7Li, 13, 14C, 26Mg, 37Cl, 41Ca(p,n), measured σ(θ=0°), GT, IAS transitions, Ep=60-200 MeV. Deduced energy dependence, interaction strength ratio |Jστ/Jτ|.
Phys. Rev. C. 25(2).
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J. Rapaport,
D. Wang,
J. A. Carr,
F. Petrovich,
C. C. Foster,
C. D. Goodman, C. Gaarde,
J. Larsen,
C. A. Goulding,
T. N. Taddeucci,
D. Horen,
E. Sugarbaker
[show abstract]
[hide abstract]
ABSTRACT: Differential cross sections and analyzing powers for the (p→,n) reaction on carbon isotopes have been measured for angles up to θlab=50° using 160 MeV protons. The angular distributions for the stronger transitions are compared with the results of distorted-wave impulse approximation calculations which utilize transition densities from existing shell model calculations. The total observed Gamow-Teller strength is also compared with the shell model predictions. In addition, the shapes of these angular distributions are discussed emphasizing decomposition into longitudinal, transverse, and non-normal-parity-transfer components. Some comparisons of the present (p,n) data with corresponding (p,p’) data and with other relevant (p,n) data are also made.
Phys. Rev. C. 36(2).
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C. Ellegaard, C. Gaarde,
T.S. Jørgensen,
J.S. Larsen,
B. Million,
C. Goodman,
A. Brockstedt,
P. Ekström,
M. Österlund,
M. Bedjidian,
D. Contardo,
D. Bachelier,
J.L. Boyard,
T. Hennino,
J.C. Jourdain,
M. Roy-Stephan,
P. Radvanyi,
P. Zupranski
[show abstract]
[hide abstract]
ABSTRACT: Spin structure and cross section data for Δ production in the (, -like reaction (, 2p[1S0]) on p, d and 12C targets are presented. At laboratory kinetic energies 2 GeV and 1.6 GeV, and forward scattering angles, we find dominance of spin transverse over spin longitudinal cross section for free Δ production. On the nucleus 12C we find significant enhancement of the transverse dominance, and a large downwards shift in the peak position of the laboratory energy transfer associated with the production of the Δ.
Physics Letters B.
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D. Bachelier,
J.L. Boyard,
T. Hennino,
J.C. Jourdain,
M. Roy-Stephan,
D. Contardo,
J.Y. Grossiord,
A. Guichard,
J.R. Pizzi,
P. Radvanyi,
J. Tinsley,
C. Ellegaard, C. Gaarde,
J.S. Larsen
[show abstract]
[hide abstract]
ABSTRACT: Excitation of the Δ resonance is observed for the first time with heavy ions. It is very strong in the two mirror charge-exchange reactions ( and at 950 MeV per nucleon. With similar incident energies per nucleon, the Δ is weakly excited with a beam and nearly absent with a beam. The role of the ejectile bound states is discussed.
Physics Letters B.
-
B. Ramstein,
C. Mosbacher,
T. Hennino,
W. Augustyniak,
D. Bachelier,
H.G. Bohlen,
J. L. Boyard,
R. Dahl,
C. Ellegaard, C. Gaarde, [......],
D. L'Hote,
H. P. Morsch,
M. Osterlund,
J Poitou,
P. Radvanyi,
M. Roy-Stephan,
T Sams,
M. Skousen,
S. Tarle-Rousteau,
P. Zupranski
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J. Rapaport,
T.N. Taddeucci,
T.P. Welch,
D.J. Horen, C. Gaarde,
J. Larsen,
E. Sugarbaker,
P. Koncz,
C.C. Foster,
C.D. Goodman,
C.A. Goulding,
T. Masterson
-
T.N. Taddeucci,
J. Rapaport,
D.E. Bainum,
C.D. Goodman,
C.C. Foster, C. Gaarde,
J. Larsen,
C.A. Goulding,
D.J. Horen,
T. Masterson,
E. Sugarbaker
[show abstract]
[hide abstract]
ABSTRACT: This work was supported by the National Science Foundation Grants NSF PHY 78-22774 A03, NSF PHY 81-14339, and by Indiana University
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C.D. Goodman,
C.C. Foster,
S.D. Bloom, C. Gaarde,
J. Larsen,
C.A. Goulding,
D.J. Horen,
T.G. Masterson,
J. Rapaport,
T.N. Taddeucci,
E. Sugarbaker
[show abstract]
[hide abstract]
ABSTRACT: This work was supported by the National Science Foundation Grants NSF PHY 78-22774 A03, NSF PHY 81-14339, and by Indiana University
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J. Rapaport,
T. Taddeucci,
C.D. Goodman,
C.C. Foster,
C.A. Goulding,
E. Sugarbaker,
D.E. Bainum,
T.G. Masterson,
D. Lind, C. Gaarde,
D. Horen
[show abstract]
[hide abstract]
ABSTRACT: This work was supported by the National Science Foundation Grant NSF PHY 78-22774 A02 & A03 and by Indiana University
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C.D. Goodman,
C.C. Foster, C. Gaarde,
J. Larsen,
J. Rapaport,
T.N. Taddeucci,
E. Sugarbaker,
D.J. Horen,
C.A. Goulding,
D.E. Bainum,
M.B. Greenfield
[show abstract]
[hide abstract]
ABSTRACT: This work was supported by the National Science Foundation Grant NSF PHY 78-22774 A02 & A03 and by Indiana University
-
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E. Sugarbaker,
P. Koncz,
D Krofcheck,
C.D. Goodman,
C.C. Foster,
J. Rapaport,
T.N. Taddeucci,
P. Welch,
S. Austin,
A. Galonsky, C. Gaarde,
J. Larsen,
D. Horen,
T. Masterson
[show abstract]
[hide abstract]
ABSTRACT: This work was supported by the National Science Foundation Grants NSF PHY 78-22774 A03, NSF PHY 81-14339, and by Indiana University
