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Control of spin polarization through recollisions

Using only linearly polarized light, we study the possibility of generating spin-polarized photoelectrons from xenon atoms. No net spin polarization is possible, since the xenon ground state is spinless, but when the photoelectrons are measured in coincidence with the residual ion, spin polarization emerges. Furthermore, we show that ultrafast dynamics of the recolliding photoelectrons contribute

“Why Not Study What Tourists Actually Do, Instead of Asking Them What They Think They Do?” A Call for More Experiments in Tourism and Hospitality Research

This chapter aims to encourage tourism researchers to widen their scope of method when studying tourist behavior. It does so by debating tracking mobility and planning exercises as meaningful complements in researchers’ method repertoire. Both methods have been found to reflect tourist behavior in a more accurate way than do, for example, surveys and interviews, which rather mirror what tourists s

Characterizing the multi-dimensional reaction dynamics of dihalomethanes using XUV-induced Coulomb explosion imaging

Site-selective probing of iodine 4d orbitals at 13.1 nm was used to characterize the photolysis of CH2I2 and CH2BrI initiated at 202.5 nm. Time-dependent fragment ion momenta were recorded using Coulomb explosion imaging mass spectrometry and used to determine the structural dynamics of the dissociating molecules. Correlations between these fragment momenta, as well as the onset times of electron

A Tale of Two Disks : Mapping the Milky Way with the Final Data Release of APOGEE

We present new maps of the Milky Way disk showing the distribution of metallicity ([Fe/H]), α-element abundances ([Mg/Fe]), and stellar age, using a sample of 66,496 red giant stars from the final data release (DR17) of the Apache Point Observatory Galactic Evolution Experiment survey. We measure radial and vertical gradients, quantify the distribution functions for age and metallicity, and explor

In-depth comparison of methanol port and direct injection strategies in a methanol/diesel dual fuel engine

For methanol/diesel dual-fuel combustion, there are two different methanol injection implementations: port injection into the intake manifold and direct injection into cylinder. In this work, an experimental comparison was conducted for the two methanol injection strategies to study the effects of the methanol-energy-substation ratio (ESR) and diesel injection timing on the fuel-air mixing and com

Single-shot, high-repetition rate carrier-envelope-phase detection of ultrashort laser pulses

We propose a single-shot, high-repetition rate measurement scheme of the carrier-envelope phase offset of ultrashort laser pulses. The spectral fringes resulting from f-2f nonlinear interferometry, encoding the carrier-envelope-phase, are evaluated completely optically via an optical Fourier transform. For demonstration, the carrier-envelope-phase of a 200 kHz, few-cycle optical parametric chirped

Two super-Earths at the edge of the habitable zone of the nearby M dwarf TOI-2095

The main scientific goal of TESS is to find planets smaller than Neptune around stars that are bright enough to allow for further characterization studies. Given our current instrumentation and detection biases, M dwarfs are prime targets in the search for small planets that are in (or near) the habitable zone of their host star. In this work, we use photometric observations and CARMENES radial ve

Photoelectron signature of dressed-atom stabilization in an intense XUV field

Nonperturbative resonant multiphoton ionization (1+1) is studied using the resolvent operator technique. Scaling parameters for effective two-level Hamiltonians are computed for hydrogen and helium atoms to provide a quantitative description of Rabi oscillations at XUV wavelengths, which were recently observed using a seeded free-electron laser [S. Nandi, Nature (London) 608, 488 (2022)0028-083610

An introduction to computational complexity and statistical learning theory applied to nuclear models

The fact that we can build models from data, and therefore refine our models with more data from experiments, is usually given for granted in scientific inquiry. However, how much information can we extract, and how precise can we expect our learned model to be, if we have only a finite amount of data at our disposal? Nuclear physics demands an high degree of precision from models that are inferre

Future trends for patient-specific dosimetry methodology in molecular radiotherapy

Molecular radiotherapy is rapidly expanding, and new radiotherapeutics are emerging. The majority of treatments is still performed using empirical fixed activities and not tailored for individual patients. Molecular radiotherapy dosimetry is often seen as a promising candidate that would allow personalisation of treatments as outcome should ultimately depend on the absorbed doses delivered and not

Towards microscopic optical potentials in deformed nuclei

A microscopic and consistent description of both nuclear structure and reactions is instrumental to extend the predictivity of models calculating scattering observables. In particular, this is crucial in the case of exotic nuclei not yet discovered. In this manuscript, we will present the plan of the Lund effort for a symmetry breaking description of bound and scattering observables using a genera

Nuclear Structure Effects in Fission

Three examples of nuclear structure effects in fission dynamics are discussed: (i) The appearance of a super-short symmetric mode in the fission of nuclei around 264Fm leading to two double-magic 132Sn, (ii) Fission of some super-heavy elements where the heavy cluster is focused around double-magic 208Pb, and (iii) A saw-tooth distribution in angular momenta versus the fission fragment mass in the

Spectroscopic factors with generator coordinate method and application to 25Mg states

Nuclei can be studied through the analysis of their shell structure, that provides important information on the wavefunctions useful for interpreting many phenomena, from excitations to transfer reactions. Spectroscopic factors provide the degree of single particle behaviour of a nuclear state and are used to represent the shell structure of a nucleus. In this manuscript, we expand our recently de

Heteroepitaxial growth modes revisited

It is well known that the outcome of a thin film deposition experiment on a foreign substrate is determined by surface and interface energetics, which can be collected in one parameter, the change in surface energy, Ω. It is common knowledge that at equilibrium conditions, Ω < 0 leads to two-dimensional (2D) growth and Ω > 0 leads to the formation of three-dimensional (3D) islands. Using classical

Beyond-Mean-Field with an Effective Hamiltonian Mapped from an Energy Density Functional

A method for beyond-mean-field calculations based on an energy density functional is described. The main idea is to map the energy surface for the nuclear quadrupole deformation, obtained from an energy density functional at the mean-field level, into an effective Hamiltonian expressed as a many-body operator. The advantage of this procedure is that one avoids the problems with density dependence

Predictors of the post-COVID condition following mild SARS-CoV-2 infection

Whereas the nature of the post-COVID condition following mild acute COVID-19 is increasingly well described in the literature, knowledge of its risk factors, and whether it can be predicted, remains limited. This study, conducted in Norway, uses individual-level register data from 214,667 SARS-CoV-2 infected individuals covering a range of demographic, socioeconomic factors, as well as cause-speci