The forward physics facility at the high-luminosity LHC

High energy collisions at the High-Luminosity Large Hadron Collider (LHC) produce a large number of particles along the beam collision axis, outside of the acceptance of existing LHC experiments. The proposed Forward Physics Facility (FPF), to be located several hundred meters from the ATLAS interaction point and shielded by concrete and rock, will host a suite of experiments to probe standard model (SM) processes and search for physics beyond the standard model (BSM). In this report, we review the status of the civil engineering plans and the experiments to explore the diverse physics signals that can be uniquely probed in the forward region. FPF experiments will be sensitive to a broad range of BSM physics through searches for new particle scattering or decay signatures and deviations from SM expectations in high statistics analyses with TeV neutrinos in this low-background environment. High statistics neutrino detection will also provide valuable data for fundamental topics in perturbative and non-perturbative QCD and in weak interactions. Experiments at the FPF will enable synergies between forward particle production at the LHC and astroparticle physics to be exploited. We report here on these physics topics, on infrastructure, detector, and simulation studies, and on future directions to realize the FPF's physics potential

Femtosecond four-wave mixing experiments on GaAs quantum wells using two independently tunable lasers

Femtosecond two beam and three beam (omega(1),omega(1);omega(2)) four-wave mixing (FWM) experiments on GaAs quantum wells have been performed using two partially synchronized, independently tunable lasers with external jitter compensation. Heavy and light hole beatings are observed with these two mutually incoherent lasers. FWM signals are observed when oz is completely below the exciton energies, with no spectral overlap with the absorption profile. These off-resonant signals are stronger than the interband continuum signals for equivalent detunings

Efficient Broadcast Encryption Scheme with Log-Key Storage

In this paper, we present a broadcast encryption scheme with efficient transmission cost under the log-key restriction. Given n users and r revoked users, our scheme has the transmission cost of O(r) and requires the storage of O(log n) keys at each receiver. These are optimal complexities in broadcast encryptions using one-way hash functions (or pseudo-random generators.) To achieve these complexities, the stratified subset difference (SSD) scheme and the B1 scheme were introduced by Goodrich et al. and Hwang et al. respectively. However, their schemes have the disadvantage that transmission cost increases linearly according to the number of stratifications. By assigning the related keys between stratifications, our scheme remedies the defect and achieves very efficient transmission cost even in an environment where the key storage is restricted. To the best of our knowledge, our scheme has the most efficient transmission cost in the existing schemes with log-key storage. In addition, our result is comparable to other schemes that allow a large key storage

No more Sunday dinners: food insecurity and welfare reform in Northeast England

info:eu-repo/semantics/publishe