B→K∗ℓ+ℓ−B\to K^* \ell^+ \ell^- decays at large recoil in the Standard Model: a theoretical reappraisal

We critically reassess the theoretical uncertainties in the Standard Model calculation of the $B \to K^* \ell^+ \ell^-$ observables, focusing on the low $q^2$ region. We point out that even optimized observables are affected by sizable uncertainties, since hadronic contributions generated by current-current operators with charm are difficult to estimate, especially for $q^2 \sim 4 m_c^2\simeq 6.8$ GeV$^2$. We perform a detailed numerical analysis and present both predictions and results from the fit obtained using most recent data. We find that non-factorizable power corrections of the expected order of magnitude are sufficient to give a good description of current experimental data within the Standard Model. We discuss in detail the $q^2$ dependence of the corrections and their possible interpretation as shifts of the Standard Model Wilson coefficients.Comment: 33 pages, 7 figures, 11 tables. v2: fixed numerical error in S4 and typos; added discussion of the impact of future measurements; conclusions unchange

On Flavourful Easter eggs for New Physics hunger and Lepton Flavour Universality violation

Within the standard approach of effective field theory of weak interactions for $\Delta B = 1$ transitions, we look for possibly unexpected subtle New Physics effects, here dubbed "flavourful Easter eggs". We perform a Bayesian global fit using the publicly available HEPfit package, taking into account state-of-the-art experimental information concerning these processes, including the suggestive measurements from LHCb of $R_{K}$ and $R_{K^{*}}$, the latter available only very recently. We parametrize New Physics contributions to $b \to s$ transitions in terms of shifts of Wilson coefficients of the electromagnetic dipole and semi-leptonic operators, assuming CP-conserving effects, but allowing in general for violation of lepton flavour universality. We show how optimistic/conservative hadronic estimates can impact quantitatively the size of New Physics extracted from the fit. With a conservative approach to hadronic uncertainties we find nonzero New Physics contributions to Wilson coefficients at the level of $\sim 3\sigma$, depending on the model chosen. Furthermore, given the interplay between hadronic contributions and New Physics effects in the leptonic vector current, a scenario with nonstandard leptonic axial currents is comparable to the more widely advocated one with New Physics in the leptonic vector current.Comment: 27 pages, 6 figures and 5 tables. v2: numerical results and plots replaced with higher statistics MC runs, references added. v3: final version to appear in EPJ

Shear viscosity of neutron matter from realistic nucleon-nucleon interactions

The calculation of transport properties of Fermi liquids, based on the formalism developed by Abrikosov and Khalatnikov, requires the knowledge of the probability of collisions between quasiparticles in the vicinity of the Fermi surface. We have carried out a numerical study of the shear viscosity of pure neutron matter, whose value plays a pivotal role in determining the stability of rotating neutron stars, in which these processes are described using a state-of-the-art nucleon-nucleon potential model. Within our approach medium modifications of the scattering cross section are consistently taken into account, through an effective interaction obtained from the matrix elements of the bare interaction between correlated states. Inclusion of medium effects lead to a large increase of the viscosity at densities larger than $\sim 0.1$ fm^{-3}.Comment: 4 pages, 4 figures. Corrected typo

Unified description of equation of state and transport properties of nuclear matter

Correlated basis function perturbation theory and the formalism of cluster expansions have been recently employed to obtain an effective interaction from a state-of-the-art nucleon nucleon potential model. The approach based on the effective interaction allows for a consistent description of the nuclear matter ground state and nucleon-nucleon scattering in the nuclear medium. This paper reports the the results of numerical calculations of different properties of nuclear and neutron matter, including the equation of state and the shear viscosity and thermal conductivity transport coefficients, carried out using the effective interaction.Comment: Invited talk at the Sixth Conference on Perspectives in Hadronic Physics (ICTP, Trieste, May 2008). To be published in the proceedings (AIP

Studio longitudinale sul benessere e le attitudini degli Studenti di Medicina e Chirurgia. Primi risultati della fase 1: Le caratteristiche degli studenti selezionati

We present the first results of a longitudinal study for the recognition and assessment of non-cognitive aspects of the candidates access to medicine course, and throughout the course. This study considered 8 CLMs equally distributed throughout the country and 980 students enrolled in the first year, in the academic year 2013-2014. Preliminary results obtained from the analysis of the questionnaire used in the research show that students expect a profession characterized by the aid for patients and socially useful, while they do not expect a low pay as well as a work activity risky for health. Students are motivated to the academic course mainly by the desire to care for others, while variously opportunistic aspects are much less relevant. Students show high capacity of self-regulation, a high level of empathy in its both aspects of propensity to engagement with others in their difficult moments, as well as of tendency to spontaneously take the perspective of others, while they are able to maintain a goal directed behavior even in the presence of suffering others. These students are basically satisfied, they show a confident and positive attitude towards life and a substantial psychological health. However, it is possible to identify a sub-group of students showing signals of psychological fragility who must be carefully monitored: their profiles will be analyzed in more detail, through in-depth interviews scheduled for the third/fourth year as part of faculties counselling services

Chromosome anomalies in bone marrow as primarycause of aplastic or hypoplastic conditions andperipheral cytopenia: disorders due to secondaryimpairment of RUNX1 and MPL genes

Background Chromosome changes in the bone marrow (BM) of patients with persistent cytopenia are often considered diagnostic for a myelodysplastic syndrome (MDS). Comprehensive cytogenetic evaluations may give evidence of the real pathogenetic role of these changes in cases with cytopenia without morphological signs of MDS. Results Chromosome anomalies were found in the BM of three patients, without any morphological evidence of MDS: 1) an acquired complex rearrangement of chromosome 21 in a boy with severe aplastic anaemia (SAA); the rearrangement caused the loss of exons 2-8 of the RUNX1 gene with subsequent hypoexpression. 2) a constitutional complex rearrangement of chromosome 21 in a girl with congenital thrombocytopenia; the rearrangement led to RUNX1 disruption and hypoexpression. 3) an acquired paracentric inversion of chromosome 1, in which two regions at the breakpoints were shown to be lost, in a boy with aplastic anaemia; the MPL gene, localized in chromosome 1 short arms was not mutated neither disrupted, but its expression was severely reduced: we postulate that the aplastic anaemia was due to position effects acting both in cis and in trans, and causing Congenital Amegakaryocytic Thrombocytopenia (CAMT). Conclusions A clonal anomaly in BM does not imply per se a diagnosis of MDS: a subgroup of BM hypoplastic disorders is directly due to chromosome structural anomalies with effects on specific genes, as was the case of RUNX1 and MPL in the patients here reported with diagnosis of SAA, thrombocytopenia, and CAMT. The anomaly may be either acquired or constitutional, and it may act by deletion/disruption of the gene, or by position effects. Full cytogenetic investigations, including a-CGH, should always be part of the diagnostic evaluation of patients with BM aplasia/hypoplasia and peripheral cytopenias

Lessons from the B0,+^{0,+} K∗0,+^{*0,+} μ+^{+} μ−^{-} angular analyses

We perform an analysis within the Standard Model of B0,+→K*0,+μ+μ− decays in light of the recent measurements from the LHCb experiment, showing that new data strengthen the need for sizable hadronic contributions and correlations among them. We then extend our analysis to new physics via the Standard Model effective theory, and carry out a state-of-the-art fit of available b→sℓ+ℓ− data, including possible hadronic contributions. We find the case of a fully left-handed operator standing out as the simplest scenario with a significance of almost 6σ

Charming penguins and lepton universality violation in b→sℓ+ℓ−b\to sℓ^+ℓ^-decays

The LHCb experiment has recently presented new results on Lepton Universality Violation (LUV) in $B→K^{(∗)}ℓ^+ℓ^−$ decays involving K$_S$ in the final state, which strengthen the recent evidence of LUV obtained in $B^+→K^+ℓ^+ℓ^−$ decays and the previous measurements of $B→K^{∗0}ℓ^+ℓ^−$. While LUV observables in the Standard Model are theoretically clean, their predictions in New Physics scenarios are sensitive to the details of the hadronic dynamics, and in particular of the charming penguin contribution. In this work, we show how a conservative treatment of hadronic uncertainties is crucial not only to assess the significance of deviations from the Standard Model but also to obtain a conservative picture of the New Physics responsible for LUV. Adopting a very general parameterization of charming penguins, we find that: (i) current data hint at a sizable q$^2$ and helicity dependence of charm loop amplitudes; (ii) conservative NP solutions to B anomalies favour a left-handed or an axial lepton coupling rather than a vector one