Enhancement of the relative (ΔS=1)/(ΔS=0) response of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi mathvariant="normal">Ca</mml:mi></mml:mrow><mml:mprescripts /><mml:mrow /><mml:mrow><mml:mn>40</mml:mn></mml:mrow><mml:mrow /><mml:mrow /></mml:mmultiscripts></mml:mrow></mml:math>at high excitation energies

Glashausser, C.; Jones, K. W.; Baker, F. T.; Bimbot, L.; Esbensen, H.; Fergerson, R. W.; Green, A; Nanda, S.; Smith, R. K.

doi:10.1103/physrevlett.58.2404

Cited by 59 publications

(13 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This fact suggests that the A5'=0 and A5 = l isovector excitations have similar magnitudes in the continuum up to an excitation energy of 18 MeV. The present result seems to be in a striking contrast to the (p^,p^') result on '^^Ca [2] in which spin excitations have been shown to appear relatively suppressed at low excitation energies but surprisingly enhanced at higher excitation energies, at a similar linear momentum transfer to our case. Three explanations may be possible: (1) dominance of isospin interaction (Vr) in the (^Li,^Be) reaction, (2) isoscalar excitations in the (p^,p^') reaction, and (3) three-body reaction processes in the (^Li,^Be) reaction.…”

contrasting

confidence: 73%

See 1 more Smart Citation

Relative strength (ΔS=1)/[(ΔS=0)+(ΔS=1)] of isovector spin excitations in the high-lying resonance region ofC12

et al. 1991

View full text Add to dashboard Cite

The relative strength (A5' = 1)/[(A5'=0)4-(A5'==1)] of isovector spin excitations, P^u in the highlying resonance region of '^C was investigated with the (^Li,''Be) reaction at EL =*26 MeV/nucleon and ^L =0° by separately measuring the (^Li,^Beg.s.) and (''Li,^Beo.43Mev) reaction channels with the ^Be-/ coincidence technique. The relative strength Psf was derived up to an excitation energy of 18 MeV in '^B and found to have a constant value of 0.4-0.5 for the continuum irrespective of excitation energy and 0.5 for the isovector dipole resonance centered at Ex =7.6 MeV. PACS numbers: 25.7aEf, 24.30.Cz, The relative strength (A5' = 1)/[(A5'=0) + (A5' = 1)] of spin excitations, P^u is defined aswhere a{/S.S =0) and G{/S.S = I) denote the cross sections resulting from AS'^O and A5' = l spin transfers in nuclei, respectively. Measurements of Fsf provide important information on the nuclear spin-isospin response function. So far, for isovector excitations, Psf has been investigated with the spin-flip probability, 5yvA^, observed by using polarized protons, especially, in the ^ji) reaction [1]. The relative strength Psf is directly related to 5' yvyv [2] aswhere a is the spin-flip probability for AS = 1 transitions and is expressed as a combination of Clebsch-Gordan coefficients [3,4]. Thus, the (p,Jt) reaction has been an excellent spectroscopic tool with AT^ = -1 for wellresolved states and isolated resonances. However, for excitations in a continuum where states excited via various values of AL, A/, and AS coexist, a nuclear structure model is needed in order to derive Psf from ^' yvA' , because a in Eq.(2) depends on AL and AJ as well as AS [3]. Therefore, in order to provide definite information on Psf for the continuum containing overlapping resonances, another tool is necessary, in which no nuclear structure model need be included. The (^Li,'^Be) reaction provides, independent of the nuclear structure model, the relative strength Psf even for the continuum and overlapping resonances. In this reaction, ^Be ejectiles are populated in either the ground state (y~;^Beo) or the first excited state (y ~,^;c=0.43 MeV; ^Bei) (ejectile excitation). Under the assumption of dominance of a one-step reaction process, the (^Li, ^Beo) reaction proceeds through either A5'=0 or 1, and the (^Li,^Bei) reaction proceeds predominantly through AS = 1 [5,6]. We have shown that these two reaction channels are separately measured by using a ^Be-/ coincidence technique [7]. Magnitudes of the A5=0 and AS = 1 excitations can be derived from transitions to a high-lying resonance region as well as discrete states by comparing the cross sections for the ^Beo and ^Bei reaction channels. Therefore, the (^Li,^Be) reaction is an unambiguous, ATz = -^\, probe for obtaining Psf, with typically better energy resolution than the (p,Ji) reaction because ^Be ejectiles may be detected by a magnetic spectrograph.In this Letter, we report on a measurement of the relative strength of isovector spin excitations in the continuum and giant resonance regions of ...

show abstract

contrasting

confidence: 73%

“…So far, for isovector excitations, Psf has been investigated with the spin-flip probability, 5yvA^, observed by using polarized protons, especially, in the ^ji) reaction [1]. The relative strength Psf is directly related to 5' yvyv [2] as…”

mentioning

confidence: 99%

Relative strength (ΔS=1)/[(ΔS=0)+(ΔS=1)] of isovector spin excitations in the high-lying resonance region ofC12

et al. 1991

View full text Add to dashboard Cite

show abstract

“…This signature is used in the present work to detect isoscalar spin strength in Ca. The present results are compared to the total spin strength localized by (p, p') scattering [9,10,14]. Measurements were performed between 3' and 7' (for a momentum transfer q between 0.26 and 0.8 fm~) and for excitation energies ranging from 6.25 to 42 MeV.…”

Section: Introductionmentioning

confidence: 98%

Isoscalar spin excitation inCa40

et al. 1992

Self Cite

View full text Add to dashboard Cite

A signature S& of isoscalar spin-transfer strength has been tested in the inelastic scattering of 400 MeV deuterons from ' C. It was then applied to the study of Ca over an angular range from 3' to 7' (momentum transfer range from 0.26 to 0.8 fm ) and an excitation energy range from 6.25 to 42 MeV. This is the first study of isoscalar spin strength in the continuum. Spin excitations were found in the 9 MeV region, and over a broad range in the continuum with a cluster strength around 15 MeV. The results are compared with spin-Hip probability measurements in proton scattering. In contrast to the total relative spin response, which is strongly enhanced at high excitation, the isoscalar relative spin response is roughly consistent with noninteracting Fermi gas values.PACS number(s): 25.45. De, 21.10.Hw, 27.40.+z

show abstract

“…An example is the spin-flip probabilities reported in Ref. 9. Th^y show a dramatic deviation from the value for free scattering.…”

mentioning

confidence: 92%

Surface response model for quasielastic scattering

Esbensen¹

1987

AIP Conference Proceedings

View full text Add to dashboard Cite

show abstract

Enhancement of the relative (ΔS=1)/(ΔS=0) response ofCa40at high excitation energies

Cited by 59 publications

References 10 publications

Relative strength (ΔS=1)/[(ΔS=0)+(ΔS=1)] of isovector spin excitations in the high-lying resonance region ofC12

Relative strength (ΔS=1)/[(ΔS=0)+(ΔS=1)] of isovector spin excitations in the high-lying resonance region ofC12

Isoscalar spin excitation inCa40

Surface response model for quasielastic scattering

Contact Info

Product

Resources

About