A5063365385- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Quantum Chromodynamics and Particle Interactions
- Cosmology and Gravitation Theories
- Particle Detector Development and Performance
- French Literature and Criticism
- Neutrino Physics Research
- High-Energy Particle Collisions Research
- French Literature and Critical Theory
- Nuclear physics research studies
- Literature and Culture Studies
- Historical and Literary Studies
- Astrophysics and Cosmic Phenomena
- Historical Studies and Socio-cultural Analysis
- French Literature and Poetry
- Particle Accelerators and Free-Electron Lasers
- French Historical and Cultural Studies
- Historical and Literary Analyses
- Nuclear Physics and Applications
- Black Holes and Theoretical Physics
- Renaissance Literature and Culture
- Atomic and Subatomic Physics Research
- Narrative Theory and Analysis
- Historical Art and Culture Studies
- Diverse Cultural and Historical Studies
Heidelberg University
1976-2025
Istituto Nazionale di Fisica Nucleare, Sezione di Padova
2025
Institute of Particle Physics
2025
Karlsruhe Institute of Technology
2000-2024
University of Freiburg
2023-2024
Heidelberg Institute for Theoretical Studies
2024
Rohde & Schwarz (Germany)
2024
Council of Science Editors
2022
European Organization for Nuclear Research
2018-2021
University of Warsaw
2016
We show that solving the flavor problem of Standard Model with a simple $U(1)_H$ symmetry naturally leads to an axion solves strong CP and constitutes viable Dark Matter candidate. In this framework, ratio mass its coupling photons is related SM fermion masses predicted within small range, as direct result observed hierarchies in quark charged lepton masses. The same determine couplings fermions, making framework very predictive experimentally testable by future precision experiments.
Axion models with generation-dependent Peccei-Quinn charges can lead to flavor-changing neutral currents, thus motivating QCD axion searches at precision flavor experiments. We rigorously derive limits on the most general effective flavor-violating couplings from current measurements and assess their discovery potential. For two-body decays we use available experimental data $q\to q' a$ decay rates for all transitions. contributions neutral-meson mixing are calculated in a systematic way...
A bstract We assess the status of past and future experiments on lepton flavor violating (LFV) muon tau decays into a light, invisible, axion-like particle (ALP), . propose new experimental setup for MEG II, MEGII-fwd , with forward calorimeter placed downstream from stopping target. Searching μ → ea is maximally sensitive to LFV ALPs, if these have nonzero couplings right-handed leptons. The set-up suppresses (left-handed) Standard Model background in direction by controlling polarization...
We address the recent anomalies in semi-leptonic B-meson decays using a model of fermion masses based on U(2) flavor symmetry. The new contributions to b → sℓℓ transitions arise due tree-level exchange Z′ vector boson gauging U(1) subgroup They are controlled by single parameter and approximately aligned Standard Model prediction, with constructive interference e-channel destructive μ-channel. current experimental data can be very well reproduced without violating existing constraints from...
We present a supersymmetric model with the flavour symmetry $$S_4 \times Z_3$$ and CP which are broken to $$Z_3$$ subgroup of in charged lepton sector $$Z_2 $$ ( $$\times ) neutrino one at leading order. This implements an approach capable predicting mixing angles Dirac as well Majorana phases terms free parameter. parameter, directly related size reactor angle $$\theta _{13}$$ , can be naturally correct order our model. Atmospheric is maximal, while $$\sin ^2 \theta _{12} \gtrsim 1/3$$ ....
We construct models with minimal field content that can simultaneously explain the muon g-2 anomaly and give correct dark matter relic abundance. These fall into two general classes, whether or not new fields couple to Higgs. For structure of without Higgs couplings, we provide analytical expressions only depend on $SU(2)_L$ representation. results allow demonstrate few in this class $(g-2)_\mu$ account for The experimental constraints perturbativity considerations exclude all such models,...
We discuss the leptonic axionlike particle (ALP) portal as a simple scenario that connects observed discrepancies in anomalous magnetic moments to dark matter relic abundance. In this framework an multi-MeV range couples SM leptons and (DM) fermion, with mass above ALP but below 1 GeV. The contributes <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mo stretchy="false">(</a:mo><a:mi>g</a:mi><a:mo>−</a:mo><a:mn>2</a:mn><a:msub><a:mo...
A bstract Hot axions are produced in the early Universe via their interactions with Standard Model particles, contributing to dark radiation commonly parameterized as ∆ N eff . In standard QCD axion benchmark models, this contribution is negligible after taking into account astrophysical limits such SN1987A bound. We therefore compute so-called astrophobic models characterized by strongly suppressed couplings nucleons and electrons, which constraints relaxed may be sizable. also construct...
We propose a class of axion models with generation-dependent Peccei-Quinn charges for the known fermions that allow one to suppress couplings nucleons and electrons. Astrophysical limits are thus relaxed, allowing masses up O(0.1) eV. The axion-photon coupling remains instead sizable, so next-generation helioscopes will be able probe this scenario. Astrophobia unavoidably implies flavor-violating experimental on processes can provide complementary probes. astrophobic viable dark matter...
As a minimal theory of fermion masses we extend the SM by heavy vectorlike fermions, with flavor-anarchical Yukawa couplings, that mix chiral fermions such small couplings arise from mixing angles. This model can be regarded as an effective description fermionic sector large class existing flavor models and thus might serve useful reference frame for further understanding hierarchies in SM. Already framework gives rise to FCNC effects through exchange massive bosons whose light get modified...
A bstract We propose a simple U(2) model of flavor compatible with an SU(5) GUT structure. All hierarchies in fermion masses and mixings arise from powers two small parameters that control the breaking. In contrast to previous models this setup can be realized without supersymmetry provides excellent fit all SM observables including neutrinos. also consider variant based on D 6 × U(1) F symmetry, which closely resembles structure, but allows for Majorana neutrino Weinberg operator....
A bstract We study a class of supersymmetric models where the strong CP problem is solved through spontaneous violation, carried out by complex scalar field that determines Yukawa couplings theory. Assuming one real component this — CPon light, we examine conditions under which it provides viable Dark Matter candidate. The to fermions are largely determined field-dependent interactions, and induce gauge bosons at 1-loop. All suppressed an undetermined UV scale, needs exceed 10 12 GeV in...
We investigate the general structure of mirror symmetry breaking in Twin Higgs scenario. show, using IR effective theory, that a significant gain fine tuning can be achieved if is broken hardly. emphasize weakly coupled UV completions naturally accommodate this analyze SUSY and present simple model with around 10% colored superpartners as heavy 2 TeV. The collider signatures models are discussed focus on extended sectors.
The strongest upper bounds on the axion mass come from astrophysical observations like neutrino burst duration of SN1987A, which depends couplings to nucleons, or white-dwarf cooling rates and red-giant evolution, involve axion-electron coupling. It has been recently argued that in variants DFSZ models with generation-dependent Peccei-Quinn charges an approximate axion-nucleon decoupling can occur, strongly relaxing SN1987A bound. However, as standard models, remains general coupled...
We propose simple scenarios where lepton flavor-violating couplings generate the observed dark matter abundance through freeze-in of an axion-like particle with mass in few keV range. Compared to flavor-diagonal freeze-in, this mechanism enhances stability, softens stellar cooling constraints and improves experimental sensitivity accelerator-based searches. These can be tested by future X-ray telescopes, some cases will almost entirely probed new searches for flavor violation at...
Excitation functions of proton-proton elastic scattering cross sections have been measured in narrow steps for projectile momenta ${p}_{p}$ (energies ${T}_{p}$) from $1100$ to $3300\mathrm{MeV}/c$ (500 2500 MeV) the angular range $35\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}{\ensuremath{\Theta}}_{\mathrm{c}.\mathrm{m}.}\ensuremath{\le}90\ifmmode^\circ\else\textdegree\fi{}$ with a detector providing...
It is pointed out that in a general class of flavour models one can identify certain universally present FCNC operators, induced by the exchange heavy messengers. Their coefficients depend on rotation angles connect and fermion mass basis. The lower bounds messenger scale are derived using updated experimental constraints operators. obtained different for operators addition they chosen set rotations. Given sensitivity expected forthcoming experiments, analysis suggests interesting room...
A bstract We study a minimal modification of Gauge Mediation in which the messenger sector couples directly to MSSM matter fields. These couplings are controlled by same dynamics that explain flavor hierarchies, and therefore parametrically as small Yukawas. This setup gives rise an interesting SUSY spectrum is calculable terms single new parameter. Due large A-terms, model can easily accommodate 126 GeV Higgs with relatively light spectrum. The structure depends on particular underlying...
We study the anatomy and phenomenology of lepton flavor violation (LFV) in context flavored gauge mediation (FGM). Within FGM, messenger sector couples directly to MSSM matter fields with couplings controlled by same dynamics that explains hierarchies SM Yukawas. Although pattern depends on particular underlying model, FGM provides a built-in suppression similar wave function renormalization or SUSY partial compositeness. Moreover, contrast these models, there is an additional left–right...
A bstract Even if Dark Matter (DM) is neutral under electromagnetism, it can still interact with the Standard Model (SM) via photon exchange from higher-dimensional operators. Here we classify general effective operators coupling DM to photons, distinguishing between Dirac/Majorana fermion and complex/real scalar DM. We provide model-independent constraints on these direct indirect detection. also constrain various DM-lepton operators, which induce DM-photon interactions RG running or...