Norbert Kaiser
YOU?
Author Swipe
View article: Sizes of the Nucleon
Sizes of the Nucleon Open
Evidences are updated and strengthened for the two-scales picture of low-energy nucleon structure as a compact `hard' valence quark core surrounded by a `soft' cloud of quark-antiquark pairs (the meson cloud). These considerations are quan…
View article: Solving the Matrix Exponential Function for Special Orthogonal Groups SO(n) up to n = 9 and the Exceptional Lie Group G2
Solving the Matrix Exponential Function for Special Orthogonal Groups SO(n) up to n = 9 and the Exceptional Lie Group G2 Open
In this work the matrix exponential function is solved analytically for the special orthogonal groups SO(n) up to n=9. The number of occurring k-th matrix powers gets limited to 0≤k≤n−1 by exploiting the Cayley–Hamilton relation. The corre…
View article: Solving the matrix exponential function for special orthogonal groups SO(n) and the exceptional G$_2$
Solving the matrix exponential function for special orthogonal groups SO(n) and the exceptional G$_2$ Open
In this work the matrix exponential function is solved analytically for the special orthogonal groups $SO(n)$ up to $n=9$. The number of occurring $k$-th matrix powers gets limited to $0\leq k \leq n-1$ by exploiting the Cayley-Hamilton re…
View article: Evidence against a strong first-order phase transition in neutron star cores: impact of new data
Evidence against a strong first-order phase transition in neutron star cores: impact of new data Open
With the aim of exploring the evidence for or against phase transitions in cold and dense baryonic matter, the inference of the sound speed and equation-of-state for dense matter in neutron stars is extended in view of recent new observati…
View article: The mass of charged pions in neutron star matter
The mass of charged pions in neutron star matter Open
We examine the behavior of charged pions in neutron-rich matter using heavy-baryon chiral perturbation theory. This study is motivated by the prospect that pions, or pion-like excitations, may be relevant in neutron-rich matter encountered…
View article: Inference of the sound speed and related properties of neutron stars
Inference of the sound speed and related properties of neutron stars Open
Information on the phase structure of strongly interacting matter at high baryon densities can be gained from observations of neutron stars and their detailed analysis. In the present work Bayesian inference methods are used to set constra…
View article: Solving the matrix exponential function for the groups SU(3), SU(4) and Sp(2)
Solving the matrix exponential function for the groups SU(3), SU(4) and Sp(2) Open
The well known analytical formula for $SU(2)$ matrices $U = \exp(i \vec τ\!\cdot\! \vec φ\,) = \cos|\vec φ\,| + i\vec τ\!\cdot\! \hatφ\, \sin|\vec φ\,|$\\ is extended to the $SU(3)$ group with eight real parameters. The resulting analytica…
View article: Radiative corrections to elastic muon-proton scattering at low momentum transfers
Radiative corrections to elastic muon-proton scattering at low momentum transfers Open
We systematically calculate the radiative corrections of order $\\alpha/\\pi$\nto elastic muon-proton scattering at low momentum transfers. These include\nvacuum polarization, photon-loop form factors of the muon and the proton,\ntwo-photo…
View article: Effects of order $α^3$ on the determination of the Pauli form factor $F_2$ of the $τ$-lepton
Effects of order $α^3$ on the determination of the Pauli form factor $F_2$ of the $τ$-lepton Open
We introduce optimal observables to measure the Pauli form factor $F_2$ of the $τ$-lepton in the pair-production process $e^-e^+ \to τ^- τ^+$ from the intensity distribution of the decay products. The spin-density matrix for the production…
View article: Influence of seed layers on the reflectance of sputtered aluminum thin films
Influence of seed layers on the reflectance of sputtered aluminum thin films Open
The fabrication of highly reflective aluminum coatings is still an important part of current research due to their high intrinsic reflectivity in a broad spectral range. By using thin seed layers of Cu, CuO x , Cr, CrO x , Au, and Ag, the …
View article: Energy per particle of nuclear and neutron matter from subleading chiral three-nucleon interactions
Energy per particle of nuclear and neutron matter from subleading chiral three-nucleon interactions Open
We derive from the subleading contributions to the chiral three-nucleon\ninteraction [published in Phys.~Rev.~C77, 064004 (2008) and Phys.~Rev.~C84,\n054001 (2011)] their first-order contributions to the energy per particle of\nisospin-sym…
View article: Density-dependent nn-potential from subleading chiral three-neutron forces: Long-range terms
Density-dependent nn-potential from subleading chiral three-neutron forces: Long-range terms Open
The long-range terms of the subleading chiral three-nucleon force [published in Phys.\,Rev.\,C77, 064004 (2008)] are specified to the case of three neutrons. From these $3n$-interactions an effective density-dependent neutron-neutron poten…
View article: Implementing Chiral Three-Body Forces in Terms of Medium-Dependent Two-Body Forces
Implementing Chiral Three-Body Forces in Terms of Medium-Dependent Two-Body Forces Open
Three-nucleon (3N) forces are an indispensable ingredient for accurate few-body and many- body nuclear structure and reaction theory calculations. While the direct implementation of chiral 3N forces can be technically very challenging, a s…
View article: Effective field theory for triaxially deformed odd-mass nuclei
Effective field theory for triaxially deformed odd-mass nuclei Open
The effective field theory for collective rotations of triaxially deformed nuclei is generalized to odd-mass nuclei by including the angular momentum of the valence nucleon as an additional degree of freedom. The Hamiltonian is constructed…
View article: Hyperon-Nuclear Interactions From SU(3) Chiral Effective Field Theory
Hyperon-Nuclear Interactions From SU(3) Chiral Effective Field Theory Open
The interaction between hyperons and nucleons has a wide range of\napplications in strangeness nuclear physics and is a topic of continuing great\ninterest. These interactions are not only important for hyperon-nucleon\nscattering but also…
View article: Density-dependent <i>NN</i> interaction from subleading chiral three-nucleon forces: Long-range terms
Density-dependent <i>NN</i> interaction from subleading chiral three-nucleon forces: Long-range terms Open
We derive from the subleading contributions to the chiral three-nucleon force\n(long-range terms, published in Phys.\\,Rev.\\,C\\,77, 064004 (2008)) a\ndensity-dependent two-nucleon interaction $V_\\text{med}$ in isospin-symmetric,\nspin-s…
View article: Behavior of the collective rotor in nuclear chiral motion
Behavior of the collective rotor in nuclear chiral motion Open
The behavior of the collective rotor in the chiral motion of triaxially\ndeformed nuclei is investigated using the particle rotor model by transforming\nthe wave functions from the $K$-representation to the $R$-representation. After\nexami…
View article: Growth of Atomic Layer Deposited Ruthenium and Its Optical Properties at Short Wavelengths Using Ru(EtCp)2 and Oxygen
Growth of Atomic Layer Deposited Ruthenium and Its Optical Properties at Short Wavelengths Using Ru(EtCp)2 and Oxygen Open
High-density ruthenium (Ru) thin films were deposited using Ru(EtCp)2 (bis(ethylcyclopentadienyl)ruthenium) and oxygen by thermal atomic layer deposition (ALD) and compared to magnetron sputtered (MS) Ru coatings. The ALD Ru film growth an…
View article: Behavior of the collective rotor in wobbling motion
Behavior of the collective rotor in wobbling motion Open
The behavior of the collective rotor in wobbling motion is investigated\nwithin the particle-rotor model for the nucleus $^{135}$Pr by transforming the\nwave functions from the $K$-representation to the $R$-representation. After\nreproduci…
View article: Effective field theory for collective rotations and vibrations of triaxially deformed nuclei
Effective field theory for collective rotations and vibrations of triaxially deformed nuclei Open
CITATION: Chen, Q. B., et al. 2018. Effective field theory for collective rotations and vibrations of triaxially deformed nuclei. Physical Review C, 97(6):064320, doi:10.1103/PhysRevC.97.064320.
View article: Tensor Fermi liquid parameters in nuclear matter from chiral effective field theory
Tensor Fermi liquid parameters in nuclear matter from chiral effective field theory Open
We compute from chiral two- and three-body forces the complete quasiparticle\ninteraction in symmetric nuclear matter up to twice nuclear matter saturation\ndensity. Second-order perturbative contributions that account for\nPauli-blocking …
View article: Meson-baryon scattering to one-loop order in heavy baryon chiral perturbation theory
Meson-baryon scattering to one-loop order in heavy baryon chiral perturbation theory Open
We calculate the T-matrices of pseudoscalar meson octet-baryon scattering to one-loop order in SU(3) heavy baryon chiral perturbation theory. The pertinent combinations of low-energy constants are determined by fitting to phase shifts of $…