<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow /><mml:mrow><mml:mn>12</mml:mn></mml:mrow></mml:msup></mml:mrow><mml:mi mathvariant="normal">C</mml:mi><mml:mrow><mml:msup><mml:mrow><mml:mo>−</mml:mo></mml:mrow><mml:mrow><mml:mn>12</mml:mn></mml:mrow></mml:msup></mml:mrow><mml:mi mathvariant="normal">C</mml:mi></mml:math>elastic scattering at intermediate energies

Ahmad, I.; Abdulmomen, M. A.; Al-Enazi, M. S.

doi:10.1103/physrevc.65.054607

Cited by 19 publications

(20 citation statements)

References 30 publications

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“…For example, enriched samples have been studied by laser hyperfine spectroscopy ͓6͔, and there is evidence that the isomer can be Coulomb excited in a multistep process from the I ϭK ϭ0 ϩ ground state ͓7͔. A more controversial observation is the stimulated decay of the isomer, induced by x rays and synchrotron radiation, which has been reported by , but refuted by Ahmad et al ͓12,13͔. The high-spin level structure of 178 Hf has been studied extensively ͓3-5,14͔, but basic knowledge gaps remain. Surprisingly, radiations emitted directly from the isomer itself are not yet well established.…”

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confidence: 98%

γrays emitted in the decay of 31-yr178Hfm2

et al. 2003

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The spontaneous decay of the K ϭ16 ϩ , 31-yr 178 Hf m2 isomer has been investigated with a 15-kBq source placed at the center of a 20-element ␥-ray spectrometer. High-multipolarity M 4 and E5 transitions, which represent the first definitive observation of direct ␥-ray emission from the isomer, have been identified, together with other low-intensity transitions. Branching ratios for these other transitions have elucidated the spin dependence of the mixing between the two known K ϭ8 Ϫ bands. The M 4 and E5 ␥-ray decays are the first strongly K-forbidden transitions to be identified with such high multipolarities, and demonstrate a consistent extension of K-hindrance systematics, with an inhibition factor of approximately 100 per degree of K forbiddenness. Some unplaced transitions are also reported. 178 Hf, has angular momentum and parity I ϭK ϭ16 ϩ (K is the angular-momentum projection on the body-fixed symmetry axis͒ and a half-life of 31 yr ͓2-5͔. Its fourquasiparticle structure is based on a broken neutron () pair and a broken proton () pair, each contributing I ϭK ϭ8 Ϫ . The exceptionally long lifetime of the isomer arises not only because of its high K value and the associated hindrance caused by the K-selection rule, but also because it lies lower in excitation energy than any other states of spin 14 or higher. This yrast trap is forced, therefore, to decay by transitions with both high multipolarity and a large change in K.On account of its long half-life and high excitation energy, the 178 Hf m2 isomer has attracted considerable interest and experimental investigation. For example, enriched samples have been studied by laser hyperfine spectroscopy ͓6͔, and there is evidence that the isomer can be Coulomb excited in a multistep process from the I ϭK ϭ0 ϩ ground state ͓7͔. A more controversial observation is the stimulated decay of the isomer, induced by x rays and synchrotron radiation, which has been reported by Collins et al. ͓8-11͔, but refuted by Ahmad et al. ͓12,13͔.The high-spin level structure of 178Hf has been studied extensively ͓3-5,14͔, but basic knowledge gaps remain. Surprisingly, radiations emitted directly from the isomer itself are not yet well established. The problem arises, in essence, because 99.9% of the isomer decay proceeds through a highly converted, 13-keV E3 transition (16Ϫ ) which has not so far been directly detected. The suggestion by Khoo and Lo "vho "iden ͓4͔ that the isomer is at 2447.4 keV, deduced from its population from higher-energy states, is in conflict with the singles conversion-electron data of van Klinken et al. ͓5͔ for a 0.1%, M 4 decay branch (16Ϫ ) which implies an excitation energy of 2446.0 keV. Although the 1.4-keV difference in proposed isomer energies is small, it is well outside statistical uncertainties, and represents a basic difficulty with the current understanding of the isomer and its decay modes.In the present ␥-␥-coincidence study, the M 4 ␥-ray transition has been clearly identified, confirming the interpretation of van Klinken et al. ͓5͔. We...

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confidence: 98%

γrays emitted in the decay of 31-yr178Hfm2

et al. 2003

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“…Here, r 0 is the range parameter and has a weak dependence on energy (see for discussions [12]). We use r 0 = 0.6 fm [8] in the energy range 2 to 200 MeV.…”

Section: The Glauber Modelmentioning

confidence: 99%

“…They may become important for differential cross sections away from forward direction (which probe collisions at smaller b), increasingly at higher energies. The Gaussian densities [34] which produce only surface textures of the nuclear density are not adequate and realistic densities are to be used (as done in [12]) to calculate these corrections. …”

Section: Tablesmentioning

confidence: 99%

“…Let us remark that the energies considered by them is much above the Coulomb barrier. The Coulomb modified Glauber model has also been used at very high energies [12] where trajectory modifications may be ineffective. There have been various prescriptions [13,14] to modify the NN cross sections due to nuclear density.…”

Section: Introductionmentioning

confidence: 99%

“…Replacing r c by the distance r cn of closest approach in the presence of both the Coulomb and the nuclear field gives the Coulomb plus Nuclear modified Glauber model (CNMGM) [9,10]. This model (CMGM/CNMGM) has been widely used in recent literature [11][12][13][14]. Warner et.…”

Section: Introductionmentioning

confidence: 99%

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Glauber model and the heavy ion reaction cross section

Shukla

2003

Phys. Rev. C

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Elastic α-Nucleus Scattering at 36 to 60 Mev/Nucleon

et al. 2011

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Working within the framework of the Coulomb modified Glauber model and using the optical limit approximation to evaluate the elastic S-matrix, we use a parameterized effective nucleon-nucleon phase shift function instead of the frequently applied Gaussian parameterization of the nucleonnucleon scattering amplitude to compute elastic differential cross sections for alpha particles. Our phenomenological ansatz contains three parameters which are adjusted in order to reproduce the alpha nucleus elastic scattering data for one nucleus at each of three beam energies. It is found that once the nucleon-nucleon phase shift function is so calibrated, our model very nicely reproduces elastic alpha scattering data on other nuclei at the same energy.

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12C−12Celastic scattering at intermediate energies

Cited by 19 publications

References 30 publications

γrays emitted in the decay of 31-yr178Hfm2

γrays emitted in the decay of 31-yr178Hfm2

Glauber model and the heavy ion reaction cross section

Elastic α-Nucleus Scattering at 36 to 60 Mev/Nucleon

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