Publications related to Chiral anomaly

Chiral Anomaly and Dynamos from Inhomogeneous Chemical Potential Fluctuations

In the standard model of particle physics, the chiral anomaly can occur in relativistic plasmas and plays a role in the early Universe, protoneutron stars, heavy-ion collisions, and quantum materials. It gives rise to a magnetic instability if the number d ...

Amer Physical Soc2024

Decay law of magnetic turbulence with helicity balanced by chiral fermions

Kohei Kamada, Jennifer Waltraud Schober

In plasmas composed of massless electrically charged fermions, chirality can be interchanged with magnetic helicity while preserving the total chirality through the quantum chiral anomaly. The decay of turbulent energy in plasmas such as those in the early ...

AMER PHYSICAL SOC2023

Chiral magnetohydrodynamics with zero total chirality

Kohei Kamada, Jennifer Waltraud Schober

We study the evolution of magnetic fields coupled with chiral fermion asymmetry in the framework of chiral magnetohydrodynamics with zero initial total chirality. The initial magnetic field has a turbulent spectrum peaking at a certain characteristic scale ...

American Physical Society2023

Anomalies from the covariant derivative expansion

Timothy Cohen

We revisit the calculation of chiral anomalies for global and gauge symmetries in the framework of the covariant derivative expansion (CDE). Due to the presence of UV divergences, the result is an ambiguous quantity that depends on the regularization proce ...

American Physical Society2023

Anomaly-free scale symmetry and gravity

Mikhail Chapochnikov, Anna Tokareva

In this Letter, we address the question of whether the conformal invariance can be considered as a global symmetry of a theory of fundamental interactions. To describe Nature, this theory must contain a mechanism of spontaneous breaking of the scale symmet ...

ELSEVIER2023

The role of the pion in the lineshape of the X(3872)

Riccardo Rattazzi, Angelo Esposito, Alfredo Glioti

We determine the contribution of long-range pion interactions to the X(3872) dynamics, assuming it is a loosely bound D-0(D) over bar*(0) molecule. Our result is based on the distorted wave Born approximation in non-relativistic quantum mechanics. Despite ...

Elsevier2023

Testing lepton flavour universality in $B^+\to K^+\pi^+\pi^-\ell^+\ell^-$ decays with LHCb

Sara Celani

This PhD thesis aims at testing one of the fundamental properties of the Standard Model (SM) of particle physics: the lepton flavour universality (LFU), which states that

W

and

Z

bosons are equally coupled to the three lepton generations. In this work, ...

EPFL2023

The present and future status of heavy neutral leptons

Lesya Shchutska, Alexey Boyarsky, Oleg Ruchayskiy, Marco Drewes, Inar Timiryasov, Jean-Loup Tastet, Juraj Klaric

The existence of nonzero neutrino masses points to the likely existence of multiple Standard Model neutral fermions. When such states are heavy enough that they cannot be produced in oscillations, they are referred to as heavy neutral leptons (HNLs). In th ...

2022

Freeze-in and freeze-out generation of lepton asymmetries after baryogenesis in the nu MSM

Mikhail Chapochnikov, Shintaro Eijima, Inar Timiryasov

The nu MSM an extension of the Standard Model by three relatively light singlet Majorana fermions N-1,N-2,N-3 allows for the generation of lepton asymmetry which is several orders of magnitude larger than the observed baryon asymmetry of the Universe. The ...

IOP Publishing Ltd2022

Outer automorphism anomalies

Brian Quinn Henning

We discuss anomalies associated with outer automorphisms in gauge theories based on classical groups, namely charge conjugations for SU(N) and parities for SO(2r). We emphasize the inequivalence (yet related by a flavor transformation) between two versions ...

Springer Nature2022

Low-scale leptogenesis with flavour and CP symmetries

Marco Drewes, Juraj Klaric, Yannis Georis

We consider a type-I seesaw framework endowed with a flavour symmetry, belonging to the series of non-abelian groups increment (3 n(2)) and increment (6 n(2)), and a CP symmetry. Breaking these symmetries in a non-trivial way results in the right-handed ne ...

Springer Nature2022

Production of a Chiral Magnetic Anomaly with Emerging Turbulence and Mean-Field Dynamo Action

Jennifer Waltraud Schober

In relativistic magnetized plasmas, asymmetry in the number densities of left-and right-handed fermions, i.e., a nonzero chiral chemical potential mu(5), leads to an electric current along the magnetic field. This causes a chiral dynamo instability for a u ...

AMER PHYSICAL SOC2022

Sleptonic SUSY: from UV framework to IR phenomenology

Majid Ekhterachian

We study an attractive scenario, "Sleptonic SUSY", which reconciles the 125 GeV Higgs scalar and the non-observation of superpartners thus far with potentially pivotal roles for slepton phenomenology: providing viable ongoing targets for LHC discovery, inc ...

Springer Nature2022

Production of Chern-Simons bosons in decays of mesons

Kyrylo Bondarenko, Pavlo Kashko

We consider the effective interaction of quarks with a new GeV-scale vector particle that couples to electroweak gauge bosons by the so-called effective Chern-Simons (CS) interaction. We call this particle the CS boson. We construct effective Lagrangian of ...

IOP Publishing Ltd2022

Constraining the baryonic feedback with cosmic shear using the DES Year-3 small-scale measurements

Eduardo Sanchez, Jonathan Andrew Blazek, Yi Zhang, Binglun Yin

We use the small scales of the Dark Energy Survey (DES) Year-3 cosmic shear measurements, which are excluded from the DES Year-3 cosmological analysis, to constrain the baryonic feedback. To model the baryonic feedback, we adopt a baryonic correction model ...

Oxford Univ Press2022

Plasmonic nanobar-on-mirror antenna with giant local chirality: a new platform for ultrafast chiral single-photon emission

Wen Chen, Kai Wang

Providing an additional degree of freedom for binary information encoding and nonreciprocal information transmission, chiral single photons have become a new research frontier in quantum optics. Without using complex external conditions (e.g., magnetic fie ...

ROYAL SOC CHEMISTRY2022

Generation of an electromagnetic field nonminimally coupled to gravity during Higgs inflation

Oleksandr Sobol

In the framework of Higgs inflation, we consider the electromagnetic field nonminimally coupled to gravity via the parity-preserving proportional to RF2 and parity-violating proportional to RF (F) over tilde terms. Using the perturbation theory to the lead ...

American Physical Society2021

S-matrix bootstrap for effective field theories: massless pions

João Miguel Augusto Penedones Fernandes, Andrea Guerrieri

We use the numerical S-matrix bootstrap method to obtain bounds on the two leading Wilson coefficients (or low energy constants) of the chiral lagrangian controlling the low-energy dynamics of massless pions. This provides a proof of concept that the numer ...

Springer Nature2021

Control of a polar order via magnetic field in a vector-chiral magnet

Helmuth Berger

Vector-chiral (VC) antiferromagnetism is a spiral-like ordering of spins which may allow ferroelectricity to occur due to loss of space inversion symmetry. In this Letter we report direct experimental observation of ferroelectricity in the VC phase of beta ...

AMER PHYSICAL SOC2021

Bounds on multiscalar CFTs in the epsilon expansion

Matthijs Jan Hogervorst

We study fixed points with N scalar fields in 4 - epsilon dimensions to leading order in epsilon using a bottom-up approach. We do so by analyzing O(N) invariants of the quartic coupling lambda(ijkl) that describes such CFTs. In particular, we show that la ...

Springer Nature2021