相关论文: Fate of Multiparticle Resonances: From $Q$-Balls t…

We consider bosons interacting through a narrow $s$-wave resonance. Such a resonance is characterized by an infinite scattering length and a large and negative effective range $r_0$. We argue that any number $N\ge3$ of bosons can form a…

We address the problem of calculating momentum distributions of particles emerging from the three-body decay of a many-body resonance. We show that these distributions are determined by the asymptotics of the coordinate-space complex-energy…

We consider finite linear or cyclic crystalline structures with molecular cells having narrow pre-threshold nuclear resonance. We prove that if the real part of such a nuclear resonance lies within the energy band (the convex hull of the…

Decay of bound states due to coupling with free particle states is a general phenomenon occurring at energy scales from MeV in nuclear physics to peV in ultracold atomic gases. Such a coupling gives rise to Fano-Feshbach resonances (FFR)…

We theoretically investigate the fate of a neutron-alpha $p$-wave resonance in dilute neutron matter, which may be encountered in neutron stars and supernova explosions. While $^5$He is known as a resonant state that decays to a neutron and…

We examine the spectrum of a massive scalar particle interacting with the strong gravitational field of a static, spherically symmetric object which is not quite massive enough to be a black hole. As was found in the case of massless…

Defects in the atomic structure of crystalline materials may spawn electronic bound states, known as \emph{defect states}, which decay rapidly away from the defect. Simplified models of defect states typically assume the defect is…

To determine the lifetimes of Efimov states of negative two-atomic ions, the problem of resonance scattering of a light particle on a pair of identical particles has been considered. An analytic expression has been obtained for resonance…

We compute energy distributions of three particles emerging from decaying many-body resonances. We reproduce the measured energy distributions from decays of two archetypal states chosen as the lowest $0^{+}$ and $1^{+}$-resonances in…

The multipole response of $^3$He$_N$ drops doped with very attractive impurities, such as a Xe atom or an SF$_6$ molecule, has been investigated in the framework of the Finite Range Density Functional Theory and the Random Phase…

We propose a new class of metastable dark energy (DE) phenomenological models in which the DE decay rate does not depend on external parameters such as the scale factor or the curvature of the Universe. Instead, the DE decay rate is assumed…

We explore physics of unstable particles when mother particle mass is around the sum of its daughter particle masses. In this case, the conventional wave function renormalization factor is ill-defined. We propose a simple resolution of the…

We theoretically study slow collisions of NH$_3$ molecules with He atoms, where we focus in particular on the observation of scattering resonances. We calculate state-to-state integral and differential cross sections for collision energies…

Three-boson Efimov physics is well known in the bound-state regime, but far less in the three-particle continuum at negative two-particle scattering length where Efimov states evolve into resonances. They are studied solving rigorous…

We analyze the survival probability of unstable particles in the context of quantum field theory. After introducing the spectral function of resonances, we show that deviations from the exponential decay law occur at short times after the…

Time evolution of the decay process of unstable particles is investigated in field theory models. We first formulate how to renormalize the non-decay amplitude beyond perturbation theory and then discuss short-time behavior of very…

In molecular collisions, resonances occur at specific energies where the colliding particles temporarily form quasi-bound complexes, resulting in rapid variations in the energy dependence of scattering cross sections. Experimentally, it has…

Quantum resonances, i.e., metastable states with a finite lifetime, play an important role in nuclear physics and other domains. Describing this phenomenon theoretically is generally a challenging task. In this work, we combine two…

We perform a direct finite nucleus calculation of the partial width of a bound Delta isobar decaying through the non-mesonic decay mode, Delta N -> NN. This transition is modeled by the exchange of the long ranged pi meson and the shorter…

We show that the electromagnetic moments of unstable particles (resonances) have an absorptive contribution which quantifies the change of the particle's lifetime in an external electromagnetic field. To give an example we compute here the…