B physics with the CDF run II upgrade

We summarize Run I results relevant to an analysis of the CP asymmetry in B\to J/\psi K_s, the CDF upgrade plans for Run II, and some of the main B physics goals related to the exploration of the origin of CP violation

Magnetic dipolar ordering and relaxation in the high-spin molecular cluster compound Mn6

Few examples of magnetic systems displaying a transition to pure dipolar magnetic order are known to date, and single-molecule magnets can provide an interesting example. The molecular cluster spins and thus their dipolar interaction energy can be quite high, leading to reasonably accessible ordering temperatures, provided the crystal field anisotropy is sufficiently small. This condition can be met for molecular clusters of sufficiently high symmetry, as for the Mn6 compound studied here. Magnetic specific heat and susceptibility experiments show a transition to ferromagnetic dipolar order at T_{c} = 0.16 K. Classical Monte-Carlo calculations indeed predict ferromagnetic ordering and account for the correct value of T_{c}. In high magnetic fields we detected the contribution of the ^{55}Mn nuclei to the specific heat, and the characteristic timescale of nuclear relaxation. This was compared with results obtained directly from pulse-NMR experiments. The data are in good mutual agreement and can be well described by the theory for magnetic relaxation in highly polarized paramagnetic crystals and for dynamic nuclear polarization, which we extensively review. The experiments provide an interesting comparison with the recently investigated nuclear spin dynamics in the anisotropic single molecule magnet Mn12-ac.Comment: 19 pages, 11 eps figures. Contains extensive discussions on dipolar ordering, specific heat and nuclear relaxation in molecular magnet

Giant isotope effect in the incoherent tunneling specific heat of the molecular nanomagnet Fe8

Time-dependent specific heat experiments on the molecular nanomagnet Fe8 and the isotopic enriched analogue 57Fe8 are presented. The inclusion of the 57Fe nuclear spins leads to a huge enhancement of the specific heat below 1 K, ascribed to a strong increase in the spin-lattice relaxation rate Gamma arising from incoherent, nuclear-spin-mediated magnetic quantum tunneling in the ground-doublet. Since Gamma is found comparable to the expected tunneling rate, the latter process has to be inelastic. A model for the coupling of the tunneling levels to the lattice is presented. Under transverse field, a crossover from nuclear-spin-mediated to phonon-induced tunneling is observed.Comment: Replaced with version accepted for publication in Physical Review Letter

Magnetic long-range order induced by quantum relaxation in single-molecule magnets

Can magnetic interactions between single-molecule magnets (SMMs) in a crystal establish long-range magnetic order at low temperatures deep in the quantum regime, where the only electron spin-fluctuations are due to incoherent magnetic quantum tunneling (MQT)? Put inversely: can MQT provide the temperature dependent fluctuations needed to destroy the ordered state above some finite Tc, although it should basically itself be a T-independent process? Our experiments on two novel Mn4 SMMs provide a positive answer to the above, showing at the same time that MQT in the SMMs has to involve spin-lattice coupling at a relaxation rate equaling that predicted and observed recently for nuclear spin-mediated quantum relaxation.Comment: 4 pages, 3 figure

Trauma-focused treatment outcome for complex PTSD patients: results of an intensive treatment programme

Objective The objective of the current study is to determine whether individuals classified as having CPTSD can benefit from an intensive trauma-focused treatment, resulting in decreased PTSD and CPTSD symptoms, and loss of diagnoses. Method Patients diagnosed with PTSD (N = 308) took part in an intensive 8-day treatment programme combining prolonged exposure, EMDR therapy, psycho-education, and physical activity. The treatment was not phase-based in that it did not contain a stabilization phase or skill training prior to therapy. CPTSD diagnosis was assessed by means of the International Trauma Questionnaire (ITQ) and PTSD diagnosis was assessed with both the ITQ and CAPS-5. Treatment response was measured with the CAPS-5, PCL-5, and ITQ. Results Symptoms of both PTSD and CPTSD significantly decreased from pre- to post-treatment resulting in a significant loss of CAPS-5 based PTSD (74.0%) and ITQ-based PTSD and CPTSD diagnoses (85.0% and 87.7%, respectively). No adverse events occurred in terms of suicides, suicide attempts, or hospital admissions. Conclusions The results are supportive of the notion that the majority of patients classified as having CPTSD strongly benefit from an intensive trauma-focused treatment for their PTSD