Evidence for the rare decay Σ+→pμ+μ−\Sigma^+ \to p \mu^+ \mu^- at LHCb

A search for the rare decay $\Sigma^+ \to p \mu^+ \mu^-$ is performed using $pp$ collision data recorded by the LHCb experiment at centre-of-mass energies $\sqrt{s} = 7$ and $8$ TeV, corresponding to an integrated luminosity of $3 fb^{-1}$. An excess of events is observed with respect to the background expectations with a signal significance of 4.0 standard deviations. No significant structure is observed in the dimuon invariant mass distribution.Comment: To appear in the Proceedings of the KAON2016 Conferenc

Production measurements at LHCb with the first data

We report on the perspective measurements of inclusive particle production in high-energy p-p collisions with data to be collected by the LHCb experiment at CERN's LHC. These include V0 and D meson production studies, which can be based on a minimum bias sample, as well as charmonia production studies, which need a muon-triggered samples. Using reconstructed $J/\psi \to \mu^+ \mu^-$ decays, both the prompt $J/\psi$ and $b\to J/\psi$ production cross-sections will be determined, in the forward pseudo-rapidity range of 2-5 covered by LHCb. Due to the large production rate, such analyses will be possible with very small integrated luminosities of the order of a few $\mathrm{pb}^{-1}$. Other charmonia related measurements will also be discussed, such as that of the $J/\psi$ polarization at production or of the production of some of the new X, Y and Z states.Comment: To be published in the proceedings of DPF-2009, Detroit, MI, July 2009, eConf C09072

Rare charm decays: an experimental review

Indirect searches, and in particular rare decays, have proven to be a fruitful field to search for New Physics beyond the Standard Model. While the down-quark sector (B and K) have been studied in detail, less attention was devoted to charm decays due to the smaller expected values and higher theoretical uncertainties of their observables. Recently a renewed interest is growing in rare charm searches. In this article we review the current experimental status of searches for rare decays in charmed hadrons. While the Standard Model rates are yet to be reached, current experimental limits are already putting constraints on New Physics models.Comment: 21 pages, 13 figures, to appear in the proceedings of The 5th International Workshop on Charm Physics (Charm 2012

Prospects for kaon physics at LHCb

Despite not being designed for it, the LHCb experiment has given world-leading contributions in kaon and hyperon physics. In this contribution I review the prospects for kaon physics at LHCb exploiting the already acquired data and the current and future Upgrade scenarios.Comment: Proceeding contribution for the International Conference on Kaon Physics 201

LHCb commissioning

LHCb is a dedicated experiment for the study of b-hadrons, exploiting the copious production of beauty mesons and baryons in proton-proton collisions at the CERN LHC. The LHCb detector was already able to take data in September 2008 and now is being commissioned for the new LHC start-up in September 2009. Cosmic rays and single beam interactions data are in use for a study of the detectors performances and for their space and time alignment. Improvements in each subdetector are being performed; moreover the last of the muon stations is being installed. Full experiment system tests have shown the readiness of LHCb from the data taking to their processing. Here the current status of the LHCb experiment commissioning is presented

First minimum bias physics results at LHCb

We report on the first measurements of the LHCb experiment, as obtained from $pp$ collisions at $\sqrt{s} = 0.9$ TeV and 7 TeV recorded using a minimum bias trigger. In particular measurements of the absolute $K^0_S$ production cross section at $\sqrt{s} = 0.9$ TeV and of the $\bar{\Lambda}/\Lambda$ ratio both at $\sqrt{s} = 0.9$ TeV and 7 TeV are discussed and preliminary results are presented.Comment: To appear in the Proceedings of the 15th International QCD Conference (QCD10) submitted to Nuc. Phys. (Proc. Suppl.

Association between attention and heart rate fluctuations in pathological worriers

Recent data suggests that several psychopathological conditions are associated with alterations in the variability of behavioral and physiological responses. Pathological worry, defined as the cognitive representation of a potential threat, has been associated with reduced variability of heart beat oscillations (i.e., decreased heart rate variability; HRV) and lapses of attention indexed by reaction times (RTs). Clinical populations with attention deficit show RTs oscillation around 0.05 and 0.01 Hz when performing a sustained attention task. We tested the hypothesis that people who are prone to worry do it in a predictable oscillating pattern revealed through recurrent lapses in attention and concomitant oscillating HRV. Sixty healthy young adults (50% women) were recruited: 30 exceeded the clinical cut-off on the Penn State Worry Questionnaire (PSWQ; High-Worry, HW); the remaining 30 constituted the Low-Worry (LW) group. After a diagnostic assessment, participants performed two 15-min sustained attention tasks, interspersed by a standardized worry-induction procedure. RTs, HRV and moods were assessed. The analyses of the frequency spectrum showed that the HW group presents a significant higher and constant peak of RTs oscillation around 0.01 Hz (period 100 s) after the induction of worry, in comparison with their baseline and with the LW group that was not responsive to the induction procedure. Physiologically, the induction significantly reduced high-frequency HRV and such reduction was associated with levels of self-reported worry. Results are coherent with the oscillatory nature of the default mode network (DMN) and further confirm an association between cognitive rigidity and autonomic nervous system inflexibility

Clinical Value of CT-Guided Fine Needle Aspiration and Tissue-Core Biopsy of Thoracic Masses in the Dog and Cat

Diagnosis of thoracic lesions on the basis of history and physical examination is often challenging. Diagnostic imaging is therefore of paramount importance in this field. Radiology has traditionally been considered the diagnostic procedure of choice for these diseases. Nevertheless, it is often not possible to differentiate inflammatory/infectious lesions from neoplastic diseases. A correct cytological and histopathologic diagnosis is therefore needed for an accurate diagnosis and subsequent prognostic and therapeutic approach. In human medicine, Computed Tomography (CT) and CT-guided biopsy are used in the presence of lesions which are not adequately diagnosed with other procedures. In the present study, thoracic lesions from 52 dogs and 10 cats of different sex, breed and size underwent both CT-guided fine-needle aspiration (FNAB) and tissue-core biopsy (TCB). Clinical examination, hematobiochemical analysis and chest radiography were performed on all animals. In this study, 59 of 62 histopathological samples were diagnostic (95.2%). Cytology was diagnostic in 43 of 62 samples (69.4%). General sensitivity, accuracy and PPV for FNAB and TCB were 67.7%, 67.7% and 100% and 96.7%, 95.2% and 98.3%, respectively. Combining the two techniques, the overall mean accuracy for diagnosis was 98.4%. Nineteen of 62 cases showed complications (30.6%). Mild pneumothorax was seen in 16 cases, whereas mild hemorrhage occurred in three cases. No major complications were encountered. CT-guided FNAB cytology can be considered a useful and reliable technique, especially for small lesions or lesions located close to vital organs and therefore dangerous to biopsy in other way