Publications (65)
Dominance of Pion-exchange in R-parity Violating Supersymmetry Contributions to Neutrinoless Double Beta Decay
Amand Faessler, Sergey Kovalenko, Fedor Simkovic +1
We present a new contribution of the R-parity violating supersymmetry (SUSY) to neutrinoless double beta decay via the pion exchange between decaying neutrons. The pion coupling to…
Quantum Channel Polynomial Processing
Tianhan Liu, Fedor Simkovic, Martin Leib
We introduce a quantum algorithmic framework based on probabilistic mixtures of unitary channels that, similar to the framework of quantum singular value transformations, enables t…
Nuclear matrix elements for neutrinoless double-beta decay and double-electron capture
Amand Faessler, Vadim Rodin, Fedor Simkovic
A new generation of neutrinoless double beta decay experiments with improved sensitivity is currently under design and construction. They will probe inverted hierarchy region of th…
Enhanced thermopower under time-dependent gate voltage
Adeline Crépieux, Fedor Simkovic, Benjamin Cambon +1
We derive formal expressions of time-dependent energy and heat currents through a nanoscopic device using the Keldysh nonequilibrium Green function technique. Numerical results are…
Neutrino mass in GUT constrained supersymmetry with R-parity violation in light of neutrino oscillations
Marek Gozdz, Wieslaw A. Kaminski, Fedor Simkovic
The neutrino masses are generated in grand unified theory (GUT) constrained supersymmetric model with R-parity violation. The neutrinos acquire masses via tree-level neutrino-neutr…
Neutrino oscillations in Quantum Field Theory
Sergey Kovalenko, Fedor Simkovic
We propose a Quantum Field Theory (QFT) approach to neutrino oscillations in vacuum. The neutrino emission and detection are identified with the charged-current vertices of a singl…
Neutrinoless Double Beta Decay of 134Xe
Fedor Simkovic, Pavol Domin, Amand Faessler
In view of recent great progress achieved in the experimental study of the neutrinoless double beta decay (0nbb-decay) of 134Xe we discuss theoretical aspects of this process. The…
Contributions of different neutron pairs in different approaches for neutrinoless double beta decay
Alberto Escuderos, Amand Faessler, Vadim Rodin +1
The methods used till now to calculate the neutrinoless double beta decay matrix elements are: the Quasiparticle Random Phase Approximation (QRPA), the Shell Model (SM), the angula…
Exact relativistic tritium beta-decay endpoint spectrum in a hadron model
Fedor Simkovic, Rastislav Dvornicky, Amand Faessler
We present the relativistic calculation of the beta-decay of tritium in a hadron model. The elementary particle treatment of the transition 3H -> 3He + e^- + nu_e is performed in a…
Feasibility and physics potential of detecting B solar neutrinos at JUNO
JUNO collaboration, Angel Abusleme, Thomas Adam +589
The Jiangmen Underground Neutrino Observatory~(JUNO) features a 20~kt multi-purpose underground liquid scintillator sphere as its main detector. Some of JUNO's features make it an…
The (muon^-,muon^+) conversion in nuclei as a probe of new physics
Fedor Simkovic, Amand Faessler, Sergey Kovalenko +1
A detailed study of the muonic analogue of neutrinoless double beta decay, (muon^-,muon^+) conversion, has been carried out for the A=44 nuclear system. We studied several lepton n…
Improved Description of One- and Two-Hole States after Electron Capture in 163 Holmium and the Determination of the Neutrino Mass
Amand Faessler, Fedor Simkovic
The atomic pair 163 Holmium and 163 Dysprosium seems due to the small Q value of about 2.3 to 2.8 keV the best case to determine the neutrino mass by electron capture. The bolomete…
Double Beta Decay
Amand Faessler, Fedor Simkovic
We review the recent developments in the field of nuclear double beta decay, which is presently an important topic in both nuclear and particle physics. The mechanism of lepton num…
Spin and charge correlations across the metal-to-insulator crossover in the half-filled Hubbard model
Aaram J. Kim, Fedor Simkovic, Evgeny Kozik
The Hubbard model with nearest-neighbour hopping on the square lattice and an average of one electron per site is known to undergo an extended crossover from metallic to insul…
Few active mechanisms of the neutrinoless double beta-decay and effective mass of Majorana neutrinos
Fedor Simkovic, John Vergados, Amand Faessler
It is well known that there exist many mechanisms that may contribute to neutrinoless double beta decay (0nbb-decay). By exploiting the fact that the associated nuclear matrix elem…
Neutrinoless double-beta decay and seesaw mechanism
Samoil M. Bilenky, Amand Faessler, Walter Potzel +1
From the standard seesaw mechanism of neutrino mass generation, which is based on the assumption that the lepton number is violated at a large (~10exp(+15) GeV) scale, follows that…
Uncovering Multiple CP-Nonconserving Mechanisms of $\betabeta$-Decay
Amand Faessler, Aurora Meroni, Serguey T. Petcov +2
We consider the possibility of several different mechanisms contributing to the $\betabeta$-decay amplitude in the general case of CP nonconservation: light Majorana neutrino excha…
Neutrino masses from R-parity non-conserving loops
Marek Góźdź, WiesÅaw A. KamiÅski, Fedor Simkovic
We present new formulae for the neutrino masses generated by R-parity violating interactions within minimal supersymmetric standard model. The importance of inclusion of CP phases…
Anderson impurity solver integrating tensor network methods with quantum computing
Francois Jamet, Lachlan P. Lindoy, Yannic Rath +6
Solving the Anderson impurity model typically involves a two-step process, where one first calculates the ground state of the Hamiltonian, and then computes its dynamical propertie…
Neutrino Mass, Electron Capture and the Shake-off Contributions
Amand Faessler, Loredana Gastaldo, Fedor Simkovic
Electron capture can determine the electron neutrino mass, while the beta decay of Tritium measures the electron antineutrino mass and the neutrinoless double beta decay observes t…
Resonance enhancement of neutrinoless double electron capture
M. I. Krivoruchenko, Fedor Simkovic, Dieter Frekers +1
The process of neutrinoless double electron capture (ECEC) is revisited for those cases where the two participating atoms are nearly degenerate in mass. The theoretical framew…
Real-space cluster dynamical mean-field theory: Center focused extrapolation on the one- and two particle level
Marcel Klett, Nils Wentzell, Thomas Schäfer +4
We revisit the cellular dynamical mean-field theory (CDMFT) for the single band Hubbard model on the square lattice at half filling, reaching real-space cluster sizes of up to 9 x…
Partial restoration of isospin symmetry for neutrinoless double beta decay in the deformed nuclear system of Nd
Dong-Liang Fang, Amand Faessler, Fedor Simkovic
In this work, we calculate the matrix elements of -decay of Nd with the deformed pn-QRPA method. We adopted the approach introduced by Rodin, Faessler [Phys. Rev.…
Running sums for -decay matrix elements within the QRPA with account for deformation
Dongliang Fang, Amand Faessler, Vadim Rodin +2
The -decay running sums for Ge and Nd nuclei are calculated within a QRPA approach with account for deformation. A realistic nucleon-nucleon residual intera…
Structure of the two-neutrino double- decay matrix elements within perturbation theory
Dusan Stefanik, Fedor Simkovic, Amand Faessler
The two-neutrino double- Gamow-Teller and Fermi transitions are studied within an exactly solvable model, which allows a violation of both spin-isospin SU(4) and isospin SU(2)…
Pion dominance in RPV SUSY induced neutrinoless double beta decay
Amand Faessler, Thomas Gutsche, Sergey Kovalenko +1
At the quark level there are basically two types of contributions of R-parity violating SUSY (RPV SUSY) to neutrinoless double beta decay: the short-range contribution involving on…
Neutrinoless double beta decay of Nd with account for deformation
Dong-Liang Fang, Amand Faessler, Vadim Rodin +1
A microscopic state-of-the-art calculation of the nuclear matrix element for neutrinoless double beta decay of Nd with an account for nuclear deformation is performed. The…
Can one measure the Cosmic Neutrino Background?
Amand Faessler, Rastislav Hodak, Sergey Kovalenko +1
The Cosmic Microwave Background (CMB) yields information about our Universe at around 380 000 years after the Big Bang (BB). Due to the weak interaction of the neutrinos with matte…
Two-neutrino double beta decay of 76Ge within deformed QRPA: A new suppression mechanism
Fedor Simkovic, Larisa Pacearescu, Amand Faessler
The effect of deformation on the two-neutrino double decay (2nbb-decay) for ground state transition 76Ge -> 76Se is studied in the framework of the deformed QRPA with separable Gam…
The light neutrino exchange mechanism of the -decay with left- and right-handed leptonic and hadronic currents revisited
Dusan Stefanik, Rastislav Dvornicky, Fedor Simkovic +1
The extension of Majorana neutrino mass mechanism of the neutrinoless double-beta decay () with the inclusion of right-handed leptonic and hadronic currents is revisited.…
Neutrinoless double beta decay of deformed nuclei within QRPA with realistic interaction
Dong-Liang Fang, Amand Faessler, Vadim Rodin +1
In this paper a microscopic state-of-the-art approach to calculation of the nuclear matrix element for neutrinoless double beta decay with an account for nuclear deformat…
Mass Testing and Characterization of 20-inch PMTs for JUNO
Angel Abusleme, Thomas Adam, Shakeel Ahmad +556
Main goal of the JUNO experiment is to determine the neutrino mass ordering using a 20kt liquid-scintillator detector. Its key feature is an excellent energy resolution of at least…
Muon capture rates: Evaluation within the Quasiparticle Random Phase Approximation
Fedor Simkovic, Rastislav Dvornicky, Petr Vogel
The Quasiparticle Random Phase Approximation (QRPA) is used in evaluation of the total muon capture ratesfor the final nuclei participating in double-beta decay. Several variants o…
Proton-neutron pairing in the deformed BCS approach
Fedor Simkovic, Charal Moustakidis, Larisa Pacearescu +1
We examine isovector and isoscalar proton-neutron pairing correlations for the ground state of even-even Ge isotopes with mass number A=64-76 within the deformed BCS approach. For…
Renormalized perturbation theory at large expansion orders
Riccardo Rossi, Fedor Simkovic, Michel Ferrero
We present a general formalism that allows for the computation of large-order renormalized expansions in the spacetime representation, effectively doubling the numerically attainab…
Pion Exchange Currents in Neutrinoless Double Beta Decay and Limits on Supersymmetry
Amand Faessler, Sergey Kovalenko, Fedor Simkovic +1
We examine the pion exchange mode of neutrinoless double beta decay induced by the R-parity violating quark-lepton operators of the supersymmetric (SUSY) extensions of the standard…
nuclear matrix elements and the occupancy of individual orbits
Fedor Simkovic, Amand Faessler, Petr Vogel
The measured occupancies of valence orbits in Ge and Se are used as a guideline for modification of the effective mean field energies that results in better descripti…
Search for the Cosmic Neutrino Background and KATRIN
Amand Faessler, Rastislav Hodak, Sergey Kovalenko +1
The spectrum of the Cosmic Microwave Background follows Planck's black body radiation formula and shows a remarkable constant temperature of T = 2.7. About 380 000 years after the…
TAO Conceptual Design Report: A Precision Measurement of the Reactor Antineutrino Spectrum with Sub-percent Energy Resolution
JUNO Collaboration, Angel Abusleme, Thomas Adam +585
The Taishan Antineutrino Observatory (TAO, also known as JUNO-TAO) is a satellite experiment of the Jiangmen Underground Neutrino Observatory (JUNO). A ton-level liquid scintillato…
The muon-positron conversion in nuclei mediated by light Majorana neutrinos
Fedor Simkovic, Pavol Domin, Sergey Kovalenko +1
We study the lepton number violating muon-positron conversion in nuclei mediated by the exchange of virtual light Majorana neutrinos. We found that a previously overlooked imaginar…
Improved Qubit Routing for QAOA Circuits
Ayse Kotil, Fedor Simkovic, Martin Leib
We develop a qubit routing algorithm with polynomial classical run time for the Quantum Approximate Optimization Algorithm (QAOA). The algorithm follows a two step process. First,…
Bilinear R-parity Violation in Neutrinoless Double Beta Decay
Amand Faessler, Sergey Kovalenko, Fedor Simkovic
We discuss some phenomenological issues of the effective quark-lepton operators emerging from the bilinear lepton-Higgs couplings in the superpotential and in the soft supersymmetr…
Nuclear and particle physics aspects of the 2nbb-decay of 150Nd
Rastislav Dvornicky, Fedor Simkovic, Amand Faessler
A discussion is given on possible realization of the Single State Dominance (SSD) hypothesis in the case of the two-neutrino double beta decay(2nbb-decay) of 150Nd with 1^- ground…
Quantum error detection in qubit-resonator star architecture
Florian Vigneau, Sourav Majumder, Aniket Rath +13
Achieving industrial quantum advantage is unlikely without the use of quantum error correction (QEC). Other QEC codes beyond surface code are being experimentally studied, such as…
Operator-Projected Variational Quantum Imaginary Time Evolution
Aeishah Ameera Anuar, Francois Jamet, Fabio Gironella +2
Variational Quantum Imaginary Time Evolution (VQITE) is a leading technique for ground state preparation on quantum computers. A significant computational challenge of VQITE is the…
Contextual Subspace Auxiliary-Field Quantum Monte Carlo: Improved bias with reduced quantum resources
Matthew Kiser, Matthias Beuerle, Fedor Simkovic
Using trial wavefunctions prepared on quantum devices to reduce the bias of auxiliary-field quantum Monte Carlo (QC-AFQMC) has established itself as a promising hybrid approach to…
Distinguishing the neutrinoless double beta decay mechanisms
Fedor Simkovic, Amand Faessler
Many new neutrinoless double beta decay (0nbb) experiments are planned or in preparation. If the 0nbb-decay will be detected, the key issue will be what is the dominant mechanism o…
The 0nbb-decay nuclear matrix elements with self-consistent short-range correlations
Fedor Simkovic, Amand Faessler, Herbert Muther +2
A self-consistent calculation of nuclear matrix elements of the neutrinoless double beta decays (0nbb) of 76Ge, 82Se, 96Zr, 100Mo, 116Cd, 128Te, 130Te and 130Xe is presented in the…
Uncertainties in the --decay nuclear matrix elements
Vadim Rodin, Amand Faessler, Fedor Simkovic +1
The nuclear matrix elements of the neutrinoless double beta decay () of most nuclei with known -decay rates are systematically evaluated using the Quasi…
Paarl Africa Underground Laboratory (PAUL)
Robert Adam, Claire Antel, Munirat Bashir +43
Establishing a deep underground physics laboratory to study, amongst others, double beta decay, geoneutrinos, reactor neutrinos and dark matter has been discussed for more than a d…
Test of Physics beyond the Standard Model in Nuclei
Amand Faessler, Fedor Simkovic
The modern theories of Grand Unification (GUT) and supersymmetric (SUSY) extensions of standard model (SM) suppose that the conservation laws of the SM may be violated to some smal…
Two-neutrino double-beta decay Fermi transition and two-nucleon interaction
Dusan Stefanik, Fedor Simkovic, Kazuo Muto +1
An exactly solvable model for a description of the two-neutrino double beta decay transition of the Fermi type is considered. By using perturbation theory an explicit dependence of…
The absolute mass of neutrino and the first unique forbidden beta-decay of 187Re
Rastislav Dvornicky, Kazuo Muto, Fedor Simkovic +1
The planned rhenium beta-decay experiment MARE might probe the absolute mass scale of neutrinos with the same sensitivity as the tritium beta-decay experiment KATRIN, which will st…
Anatomy of nuclear matrix elements for neutrinoless double-beta decay
Fedor Simkovic, Amand Faessler, Vadim Rodin +2
We show that, within the Quasiparticle Random Phase Approximation (QRPA) and the renormalized QRPA (RQRPA) based on the Bonn CD nucleon-nucleon interaction, the competition between…
Overconstrained estimates of neutrinoless double beta decay within the QRPA
Amand Faessler, Gianluigi Fogli, Eligio Lisi +3
Estimates of nuclear matrix elements for neutrinoless double beta decay (0nu2beta) based on the quasiparticle random phase approximations (QRPA) are affected by theoretical uncerta…
Ground state phase diagram of the repulsive fermionic Hubbard model on the square lattice from weak-coupling
Fedor Simkovic, Xuan-Wen Liu, Youjin Deng +1
We obtain a complete and exact in the weak-coupling limit () ground state phase diagram of the repulsive fermionic Hubbard model on the square lattice for filling…
Arbitrary mass Majorana neutrinos in neutrinoless double beta decay
Amand Faessler, Marcela Gonzalez, Sergey Kovalenko +1
We revisit the mechanism of neutrinoless double beta (NLDBD) decay mediated by the exchange with the heavy Majorana neutrino N of arbitrary mass mN, slightly mixed with the electro…
Grand unified theory constrained supersymmetry and neutrinoless double beta decay
Andrzej Wodecki, Wieslaw A. Kaminski, Fedor Simkovic
We analyze the contributions to the neutrinoless double decay (-decay) coming from the Grand Unified Theory (GUT) constrained Minimal Supersymmetric Standard Model (M…
Nuclear muon-positron conversion mediated by Majorana neutrinos
Pavol Domin, Amand Faessler, Sergey Kovalenko +1
We study lepton number violating (LNV) process of muon-positron conversion in nuclei mediated by the exchange of light and heavy Majorana neutrinos. Nuclear structure calculations…
Origin and fate of the pseudogap in the doped Hubbard model
Fedor Simkovic, Riccardo Rossi, Antoine Georges +1
We investigate the doped two-dimensional Hubbard model at finite temperature using controlled diagrammatic Monte Carlo calculations allowing for the computation of spectral propert…
Pions in Nuclei and Manifestations of Supersymmetry in Neutrinoless Double Beta Decay
Amand Faessler, Sergey Kovalenko, Fedor Simkovic
We examine the pion realization of the short ranged supersymmetric (SUSY) mechanism of neutrinoless double beta decay. It originates from the R-parity violating quark-lepton intera…
Low-Weight High-Distance Error Correcting Fermionic Encodings
Fedor Simkovic, Martin Leib, Francisco Revson F. Pereira
We perform an extended numerical search for practical fermion-to-qubit encodings with error correcting properties. Ideally, encodings should strike a balance between a number of th…
Transition magnetic moments of Majorana neutrinos in supersymmetry without R-parity in light of neutrino oscillations
Marek Gozdz, Wieslaw A. Kaminski, Fedor Simkovic +1
The transition magnetic moments of Majorana neutrinos are calculated in grand unified theory (GUT) constrained Minimal Supersymmetric Standard Model (MSSM) with explicit R-parity v…
Beta Decaying Nuclei as a Probe of Cosmic Neutrino Background
Rastislav Hodak, Sergey Kovalenko, Fedor Simkovic +1
We analyze the possibility of detection of cosmological relic neutrinos via neutrino capture on beta decaying nuclei. This reaction has no threshold in neutrino energy, which is cr…
Two-neutrino double beta decay of deformed nuclei within QRPA with realistic interaction
Mohamed Saleh Yousef, Vadim Rodin, Amand Faessler +1
A method to implement realistic nucleon-nucleon residual interaction (Bonn CD force) based on the Brueckner G-matrix into the Quasiparticle Random Phase Approximation (QRPA) for de…