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The Frontiers and Careers (F&C) is a workshop for Ph.D. students and postdoctoral researchers, and will precede the 2023 Electromagnetic Interactions with Nucleons and Nuclei (EINN) conference.
The 2023 F&C will continue to provide Ph.D. students and postdoctoral researches in the field of nuclear and hadronic physics a place to discuss and present their research, explore career prospects, and make professional connections, all with the express purpose of preparing themselves for their future careers.
Academic writing is a struggle for many young scientists as they are rarely given formal instruction on this topic. Since success in the academic field is highly dependent on publication, it is important that all researchers learn scientific writing essentials. With the appropriate toolkit, academic texts become comprehensive and interesting.
This talk will provide you with tips and tricks to make your life easier when writing. Open discussion and questions are encouraged!
Born in war, nuclear science was first revealed to the world in horror. The Cold War, power plant disasters, and current political tensions continue to play into people’s fears of everything nuclear. Overcoming this perspective often feels like an almost insurmountable task. This talk will focus on strategies to lower the barrier in speaking of nuclear science to the general public including the author’s public scholarship endeavors.
I will present d-fine, a large European consulting firm focused on analytical and quantitative challenges and the development of sustainable technological solutions.
In particular, I will discuss career paths at d-fine, and I will shed some light on d-fine's project portfolio. Zooming in on my own personal project history, I will give a sneak peek into applications of Fourier theory to the valuation of financial derivatives.
The presentation will provide an overview of how I understand current career-development opportunities in EU academia.
Short Range Correlations (SRCs) are a phenomenon found in all nuclei where two nucleons form a strongly interacting, close-proximity pair in the nucleus, leading to a large relative momentum between the nucleons. Electron-scattering experiments, many of them conducted at Jefferson Lab, have determined that the prevalence of SRCs increase with nuclear size, and furthermore that most SRCs form between a neutron and a proton, a property called ‘np-dominance.’ Since these observations have largely come from the same type of experiment, it is possible that they are biased by reaction-specific effects, for example, final state interactions and specific kinematic regimes. To test this, an experiment was conducted in Hall D in Fall 2021 using a photon beam on deuterium, helium, and carbon targets to probe SRCs through photoproduction reactions to test the validity of many previous SRC observations. To benchmark the results of this experiment, I use a theoretical prescription called Generalized Contact Formalism (GCF) to simulate photoproduction from nucleons in SRCs using various models of the nucleon-nucleon interaction potentials. I have performed a study that compares predictions of these different models for $ρ^0$ photoproduction and have propagated my predictions through the GlueX simulation and reconstruction software. I will show the results of this study and compare to preliminary results from data.
We propose a novel direct search experiment for the hypothetical X17 particle. In recent years researchers from the ATOMKI Collaboration have reported anomalous signals around 17 MeV in excited 8Be, 4He and 12C nuclear decays via internal pair creation. On the theory side this has set off a flurry of research, which found that the anomalies could be explained by a new light (~17 MeV) pseudoscalar, vector or axial-vector boson, dubbed X17. To provide an independent confirmation of such particle in the production process on a nucleon, the γn → e+e-n process has been proposed. Experimentally it is possible to study this reaction in quasi-free production on a deuteron, i.e., γd → e+e-pn, using neutron tagging, where the neutron is bound inside a deuteron. We calculate the cross section for dilepton photoproduction on a quasi-free nucleon, and optimize the kinematics for the quasi-free neutron region with the upcoming MAGIX@MESA experiment in mind. We show that the X17 signal is clearly visible above the QED background. Moreover, we show that the same measurements can be used to extract the neutron polarizabilities.
Over the past two decades a plethora of new exotic states containing heavy quarks have been discovered above open heavy-flavor thresholds.
For these states, which cannot be interpreted as quark anti-quark bound states, a number of different explanations have been put forward in terms of tetraquark states based on QCD diquarks, QCD hybrids, hadronic molecules, among others. In the past couple of years, LHCb has reported the first observation of exotic states, in particular the X(6900), comprised of only heavy quarks decaying into $J/\Psi$ $J/\Psi$. Very recently, several more states have been reported by the CMS and ATLAS collaborations in the di-$J/\Psi$ and $J/\Psi$ $\Psi(2S)$ spectra, which have been interpreted as all-charm tetraquarks. In this work, we review non-relativistic potential models for the all-charm tetraquark states, as diquark anti-diquark bound states, and explore how well these describe the structures obtained from the various experiments. Within such models, the most plausible explanation for $X(6900)$ is either as a scalar ($0^{++}$) meson or as a tensor ($2^{++}$) meson. Subsequently, we calculate the two-photon decay widths of these states within the potential model for both $0^{++}$ and $2^{++}$ quantum number assignments. The resulting two-photon decay widths allow to predict the light-by-light scattering cross sections and check if any excess, in comparison to the Standard Model prediction, seen in ongoing ATLAS experiments can be attributed to such exotic states.
Many people in academia convinced: Data Science can be a rewarding alternative to academia, and academics do have many qualities that make them attractive candidates for data science roles.
The sad truth is that such transition can easily take a year and sometimes even longer. So this is a marathon. Accomplishing it faster and at the right place requires preparation. 'Preparation for marathon' means research in the field. And as a professional researcher you know how important it is to ask the right questions. In this talk we will have a look at Data Science landscape and what you should focus on shall you decide to become a Data Scientist.
Discoveries and technological advances spurred by the demands of fundamental physics research find applications in many disciplines, including providing benefit to society through the treatment and diagnosis of disease. Rather than survey the manifold applications of this topic, a few examples will be presented with some emphasis on the ''bench to bedside'' implementation of nuclear physics technology. In parallel, the variety of physics career options along this path will be discussed.
Axions and axion-like particles (ALPs) are one of the most widely discussed extensions of the Standard Model when it comes to the strong CP problem and dark matter candidates. Current experiments are focused on the indirect searches of invisible pseudoscalars in a wide parameter range. In this paper we investigate limits on ALP mass, and its couplings to photons and leptons from 3-photon annihilation at e+ e- colliders. We provide detailed calculations and apply them to the particular kinematics of the Belle II experiment, covering the ALP mass range from few hundred MeV to around 10 GeV. Our results, which improve upon previous analyses by also including the ALP coupling to electrons, show that such future analyses will allow to significantly extend the ALP search range and impose much more stringent restrictions on their couplings.
The search for Dark Matter is an integral part of New Physics searches, however, Dark Matter has yet to be observed directly. Theoretical models provide a large parameter space for Dark Matter and allow for different properties of the particles. Models incorporating so-called portal interactions, where Dark Matter interacts with Standard Model particles through a mediator particle, are of special interest. Examples for these are Dark Photon and Axion models, which can be studied at low energy accelerator facilities.
The DarkMESA experiment is a beam dump experiment located at the upcoming accelerator MESA at the JGU Mainz. The accelerator provides an electron beam of 155 MeV and 150 $\mu$A in extracted beam mode, which, along with the high-power beam dump of the P2 experiment, provides an ideal environment for Light Dark Matter searches.
To accurately predict the expected reach and the impact of the detector design of the DarkMESA experiment on it with respect to different Dark Matter models, most notably Dark Photon and Axion mediated models, a GEANT4 simulation is used. Here, the current status of the simulations is discussed.
Spectroscopy experiments at the precision frontier allow us to study low-energy nuclear structure, test bound-state QED, refine fundamental constants, and potentially find New Physics. As the experimental uncertainties are continuously improved, theory predictions need to follow suit.
The finite-size corrections to the spectra of hydrogen-like atoms are often expanded in terms of the moments of the nuclear charge distribution, e.g. the charge and Friar radii. Contributions to the form factors that involve scales lighter than the inverse Bohr radius of the system can break this expansion.
In this talk, we illustrate the breaking and explain how spectroscopy experiments can probe physics beyond the Standard Model.
We explore the phase structure of the lattice Schwinger model in the presence of a toplogical $\theta$-term, a regime in which conventional Monte Carlo simulations suffer from the sign problem, using the variational quantum eigensolver (VQE). Constructing a suitable variational ansatz circuit for the lattice model using symmetry-preserving 2-qubit gates, we perform classical simulations showing that the ansatz is able to capture the relevant physics. In particular, we observe the remnants of the well known first-order phase transition at $\theta=\pi$ occurring in the continuum model for large enough fermion masses. Furthermore, we implement our ansatz on IBM’s superconducting quantum hardware. Using state-of-the art noise suppression techniques, namely readout error mitigation, dynamical decoupling, Pauli twirling, and zero-noise extrapolation, we are able to explore the phase structure of the model directly on quantum hardware with up to 12 qubits. We study two regimes on the hardware device, a fermion mass well below the transition point and a fermion mass well above. In both cases, our ansatz performs well and we obtain data, which are in good agreement with exact diagonalization.
The anomalous magnetic moment of the muon, $a_\mu = (g-2)_\mu/2$, is one of the most precisely measured observables of the Standard Model. However, its value shows a sizeable discrepancy to the Standard Model prediction. It is still under discussion whether this discrepancy is a hint for New Physics or a proof for the limited understanding of strong interaction at low energies. To get a better understanding of this discrepancy, one needs to reduce the uncertainty of both, the Standard Model prediction and the direct measurement.
Information on the production of pion pairs in two-photon fusion processes plays an important role in the dispersive calculation of the hadronic light-by-light scattering contribution to $a_\mu$, which is one of the two large contributions to the Standard Model predictions uncertainty. The BESIII experiment, located at the institute of high energy physics in Beijing/China, offers a perfect testbed for the investigation of two-photon processes at small momentum transfers. The process $e^+e^-\to e^+ e^-\pi^0\pi^0$ is measured at the BESIII experiment at centre-of-mass energies between 3.68 and 4.7$\,$GeV with a total integrated luminosity of more than 20$\,$fb$^{-1}$, with more data being available in future. This presentation will discuss the current status of the analysis.
The anomalous magnetic moment of the muon $a_\mu=(g_\mu-2)/2$ is one of the most precisely measured quantities in modern physics. However, there is a sizable discrepancy between the Standard Model (SM) prediction of the Muon $g-2$ Theory Initiative and the experimental average of the latest direct measurements at BNL and FNAL. This discrepancy is known as the Muon $g-2$ puzzle. For the SM prediction the main uncertainty arises from hadronic contributions and can be improved systematically using measurements of hadronic cross sections at $e^+ e^-$ colliders. One of the most important processes is $e^+ e^- \rightarrow \pi^+ \pi^-$. Using a data set of $1.9\,$fb$^{-1}$ (in the near future $20\,$fb$^{-1}$) at a center of mass energy of $3.77\,$GeV, the $\pi^+ \pi^-$ cross section is measured at the BESIII experiment located at the BEPCII collider in Beijing, exploiting the initial state radiation technique at small angles. The analysis aims to determine the pion form factor at masses above $0.8\,$GeV, which is also interesting for hadron spectroscopy. The presentation will discuss the current status of this work.
In this talk I will start from my own "mixed" career experience, between various EU countries and the US, to provide advice to young scientists interested in pursuing a career in fundamental research either in Europe or in America.
Lepton-flavor-violating decays of light pseudoscalars, $P = \pi^0, \eta,\eta' \to \mu e$, are stringently suppressed in the Standard Model up to tiny contributions from neutrino oscillations, so that their observation would be a clear indication for physics beyond the Standard Model.
However, in effective field theory such decays proceed via axial-vector, pseudoscalar, or gluonic operators, which are, at the same time, probed in spin-dependent $\mu \to e$ conversion in nuclei.
We derive master formulae that connect both processes in a model-independent way in terms of Wilson coefficients, which in the case of $\mu \to e$ conversion in nuclei requires input for the nuclear matrix elements including the charge density to account for the bound-state physics, and study the implications of current μ → e limits in titanium for the P → μe decays. We find that these indirect limits surpass direct ones by many orders of magnitude.
based on: Phys.Rev.Lett. 130 (2023) 13, 131902
We investigate contributions of excited states to nucleon matrix elements by studying the two- and three-point functions using nucleon and pion-nucleon interpolating fields. This study is made using twisted mass fermion ensembles with pion masses 346 MeV and 131 MeV. We construct an improved nucleon interpolating field with the generalized eigenvalue problem of two-point functions, and use it to study three-point functions. This method itself is also discussed in more details. We compare results obtained using these two ensembles and show preliminary results for nucleon charges.
A well-known challenge when simulating Lattice Gauge theories (LGT) is so-called critical slowing down, which refers to the exponential increase of the autocorrelation time as the lattice spacing is reduced and approaches the continuum limit. Previously, normalizing flows, combined with Lüscher’s trivializing maps, have been proposed as an alternative approach to Hybrid Monte Carlo (HMC), involving flowing gauge-field configurations, sampled independently from a uniform distribution, to the desired theory. The flow can be modelled by a parametrized function, namely a bijective map with parameters that can be trained using machine learning techniques. The trained model can then be used to generate proposals in a Markov Chain Monte Carlo (MCMC). In this talk, we present an application of this approach to simulate the U(1) gauge theory in two dimensions. We begin with an introduction of the method, details of the approach used, discuss its scalability, and conclude with some preliminary results.
Chern-Simons gauge theories have a deep and broad impact on a wide range of physics research, ranging from parity anomalies in quantum field theory to the theory of the integer and fractional quantum Hall effects, and the effective field theory description of chiral spin liquids in condensed matter physics. Despite the fact that Chern-Simons theories are well understood as a continuum field theory, there is still limited knowledge on how to find a compact Hamiltonian lattice formulation in 2+1 dimensions. This task turns out to be highly nontrivial, and we take a first step towards a lattice formulation by considering quantum electrodynamics on the lattice in the presence of a Chern-Simons term. We propose a compact lattice formulation for the Chern-Simons term in terms of the usual operators acting on the links, which we benchmark numerically against theoretical predictions. Our formulation is completely general and also suited for other Hamiltonian approaches such as quantum computing.
We evaluate the transverse momentum-dependent parton distribution functions for the pion and kaon by computing the quasi-beam functions with asymmetric staple-shaped quark bilinear operators and combine it with the soft function and Collins-Soper kernels. These are computed within lattice QCD using an $\mathcal{N}_f= 2 + 1 + 1$ twisted mass fermion ensemble of lattice size $24^3 \times 48$, lattice spacing $a= 0.093$ fm, pion mass of $350$ MeV and kaon mass of $554$ MeV. We study the mixing pattern of the extended operators composed of an asymmetric staple-shaped Wilson line through symmetry arguments and implement non-perturbative renormalization within both the RI/MOM scheme and a variant scheme, where the renormalization factors are computed at short distances.
We compute the quark and gluon momentum fraction for the pion and kaon. This is done by employing lattice quantum chromodynamics simulations. We use three gauge ensembles of twisted mass fermions generated by the Extended Twisted Mass Collaboration with two degenerate light quarks and non-degenerate strange and charm quarks. All quark masses are tuned to approximately their physical values. Stout smearing is used on the gluon loops to reduce ultra violet gauge noise. We use these three gauge ensembles with lattice spacings a = 0.08 fm, 0.068 fm and 0.57 fm to take, for the first time, the continuum directly at physical pion mass. Renormalisation factors are computed non-perturbatively within the RI’ scheme for the quark and gluon operators. Mixing between the quark and gluon is taken into account perturbatively. We check the momentum sum in the continuum limit.
Neutrons play a dominant role in the stellar nucleosynthesis of heavy elements. We review a scheme for the experimental determinations of neutron-induced reaction cross sections using a high-intensity neutron source based on the 18O(p,n)18F reaction with an 18O-water target at SARAF’s upcoming Phase II. The quasi-Maxwellian neutron spectrum with effective thermal energy kT ≈ 5 keV, characteristic of the target (p,n) yield at proton energy Ep ≈ 2.6 MeV close to its neutron threshold, is well suited for laboratory measurements of MACS of neutron-capture reactions, based on activation of targets of astrophysical interest along the s-process path. 18O-water’s vapour pressure requires a separation in between the accelerator vacuum and the target chamber. The high-intensity proton beam (in the mA range) of SARAF is incompatible with a solid window in the beam’s path. Our suggested solution is the use of a Plasma Window, which is a device that utilizes ionized gas as an interface between vacuum and atmosphere, and is useful for a plethora of applications in science, engineering and medicine. The high power dissipation (few kW) at the target is expected to result in one of the most intense sources of neutrons available at stellar-like energies. Preliminary results concerning proton beam energy loss and heat deposition profiles for target characteristics and design, a new full-scale 3-dimensional computer-aided design model of the Plasma Window (as well as its operation principles) and the planned experimental scheme, will be reviewed.