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arXiv · 1610.09748

Scalar quanta in Fermi liquids: zero sounds, instabilities, Bose condensation, and a metastable state in dilute nuclear matter

E. E. Kolomeitsev·D. N. Voskresensky
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Abstract

Spectrum of bosonic scalar-mode excitations in a normal Fermi liquid with a local scalar interaction is investigated for various values and momentum dependence of the scalar Landau parameter $f_0$ in the particle-hole channel. For $f_0 >0$ the conditions are found when the phase velocity on the spectrum of the zero sound acquires a minimum at a non-zero momentum. For $-1 0$. We also argue that in peripheral heavy-ion collisions the Pomeranchuk instability may occur already for $f_0 >-1$.

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E. E. Kolomeitsev, D. N. Voskresensky. 2016-10-31. Scalar quanta in Fermi liquids: zero sounds, instabilities, Bose condensation, and a metastable state in dilute nuclear matter. https://doi.org/10.1140/epja%2Fi2016-16362-0

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