OpenAccess

The increase in luminosity and center of mass energy at the FCC-hh will open up new clean channels where BSM contributions are enhanced at high energy. In this paper we study one such channel, Wh → ℓνγγ. [...]

This work investigates if and how photoelectron diffraction might become a suitable tool to measure structural changes of small molecules in the gas-phase with femtosecond temporal and angstrom spatial resolution. Molecular-frame photoelectron angular distributions (MFPAD) of O(1$s$)-, S(2$p$)- and F(1$s$)-electrons from carbonyl sulfide and fluoromethane molecules have been measured in photoelectron-photoion coincidence experiments at the synchrotron radiation sources DORIS and PETRA III (kinetic energy of photoelectrons: 16 eV < E$_{\mathrm{PE}}$ < 283 eV). [...]

We construct an ϵ-deformation of W algebras, corresponding to the additive version of quiver algebras which feature prominently in the 5D version of the BPS/CFT correspondence and refined topological strings on toric Calabi–Yau’s. This new type of algebras fill in the missing intermediate level between q-deformed and ordinary W algebras. [...]

This is the writeup of the lectures given at the Winter School ‘YRISW 2018’ to appear in a special issue of J. Phys. [...]

Unstable heavy particles well above the TeV scale are unaccessible experimentally. So far, Big-Bang Nucleosynthesis (BBN) provides the strongest limits on their mass and lifetime, the latter being shorter than 0.1 second. [...]

Self-interacting dark matter has been proposed to explain the apparent mass deficit in astrophysical small-scale halos, while observations from galaxy clusters suggest that the corresponding cross section depends on the velocity. Accounting for this is often believed to be highly model-dependent with studies mostly focusing on scenarios with light mediators. [...]

We measured the transverse coherence at FLASH2, a variable gap undulator line at the FLASH free-electron laser user facility at DESY in Hamburg. We demonstrate, theoretically and experimentally, a revised version of Young's double pinhole approach to perform single-shot, repeatable and non-invasive transverse coherence measurements. [...]

A resistively-heated dynamic diamond anvil cell (RHdDAC) setup is presented. The setup enables the dynamic compression of samples at high temperatures by employing a piezoelectric actuator for pressure control and internal heaters for high temperature. [...]

The influence of the contracted corrole macrocycle, in comparison to the larger porphyrin macrocycle, on the electronic structure of nickel was studied with X-ray and ultraviolet photoelectron spectroscopy (XPS, UPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Synthesis and in situ characterization of the Ni complexes of octaethylporphyrin (NiOEP) and hexaethyldimethylcorrole (NiHEDMC) were performed in ultra-high vacuum. [...]

Copper‐oxo clusters exchanged in zeolite mordenite are active in the stoichiometric conversion of methane to methanol at low temperatures. Here, we show an unprecedented methanol yield per Cu of 0.6, with a 90–95 % selectivity, on a MOR solely containing [Cu$_3$($\mu$‐O)$_3$]$^{2+ }$active sites. [...]