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تسجيل مستخدم جديدThe Isoscalar Giant Dipole Resonance in 208Pb and the Nuclear incompressibility
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The isoscalar giant dipole resonance (ISGDR) has been investigated in 208Pb using inelastic scattering of 400 MeV alpha particles at forward angles, including 0deg. Using the superior capabilities of the Grand Raiden spectrometer, it has been possible to obtain spectra devoid of any instrumental background. The ISGDR strength distribution has been extracted from a multipole-composition of the observed spectra. The implication of these results on the experimental value of nuclear incompressibility are discussed.
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The excitation and subsequent proton decay of the isoscalar giant dipole resonance (ISGDR) in $^{208}$Pb have been investigated via the $^{208}$Pb($alpha, alpha^{prime}p)^{207}$Tl reaction at 400 MeV. Excitation of the ISGDR has been identified by th
e difference-of-spectra method. The enhancement of the ISGDR strength at high excitation energies observed in the multipole-decomposition-analysis of the singles $^{208}$Pb($alpha,alpha^{prime}$) spectra is not present in the excitation energy spectrum obtained in coincidence measurement. The partial branching ratios for direct proton decay of ISGDR to low-lying states of $^{207}$Tl have been determined and the results are compared with predictions of continuum random-phase-approximation (CRPA) calculations.
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