K-ary n-cube based off-chip communications architecture for high-speed packet processors

We present a detailed study of Higgs boson production in association with a single top quark at the LHC, at next-to-leading order accuracy in QCD. We consider total and differential cross sections, at the parton level as well as by matching short distance events to parton showers, for both t-channel and s-channel production. We provide predictions relevant for the LHC at 13 TeV together with a thorough evaluation of the residual uncertainties coming from scale variation, parton distributions, strong coupling constant and heavy quark masses. In addition, for t-channel production, we compare results as obtained in the 4-flavour and 5-flavour schemes, pinning down the most relevant differences between them. Finally, we study the sensitivity to a non-standard-model relative phase between the Higgs couplings to the top quark and to the weak bosons

tWH associated production at the LHC

We study Higgs boson production in association with a top quark and a $W$ boson at the LHC. At NLO in QCD, $tWH$ interferes with $t\bar t H$ and a procedure to meaningfully separate the two processes needs to be employed. In order to define $tWH$ production for both total rates and differential distributions, we consider the diagram removal and diagram subtraction techniques that have been previously proposed for treating intermediate resonances at NLO, in particular in the context of $tW$ production. These techniques feature approximations that need to be carefully taken into account when theoretical predictions are compared to experimental measurements. To this aim, we first critically revisit the $tW$ process, for which an extensive literature exists and where an analogous interference with $t \bar t$ production takes place. We then provide robust results for total and differential cross sections for $tW$ and $tWH$ at 13 TeV, also matching short-distance events to a parton shower. We formulate a reliable prescription to estimate the theoretical uncertainties, including those associated to the very definition of the process at NLO. Finally, we study the sensitivity to a non-Standard-Model relative phase between the Higgs couplings to the top quark and to the $W$ boson in $tWH$ production.Comment: v3: expanded some discussions in the text, improved some plots (results unchanged

Lifting degeneracies in Higgs couplings using single top production in association with a Higgs boson

Current Higgs data show an ambiguity in the value of the Yukawa couplings to quarks and leptons. Not so much because of still large uncertainties in the measurements but as the result of several almost degenerate minima in the coupling profile likelihood function. To break these degeneracies, it is important to identify and measure processes where the Higgs coupling to fermions interferes with other coupling(s). The most prominent example, the decay of $h \to \gamma \gamma$, is not sufficient to give a definitive answer. In this Letter, we argue that $t$-channel single top production in association with a Higgs boson, with $h\to b\bar b$, can provide the necessary information to lift the remaining degeneracy in the top Yukawa. Within the Standard Model, the total rate is highly reduced due to an almost perfect destructive interference in the hard process, $W b \rightarrow t h$. We first show that for non-standard couplings the cross section can be reliably computed without worrying about corrections from physics beyond the cutoff scale $\Lambda\gtrsim 10\,\mathrm{TeV}$, and that it can be enhanced by more than one order of magnitude compared to the SM. We then study the signal $p p \rightarrow t h j (b)$ with 3 and 4 $b$'s in the final state, and its main backgrounds at the LHC. We find the 8 TeV run dataset to be sensitive to the sign of the anomalous top Yukawa coupling, while already a moderate integrated luminosity at 14 TeV should lift the degeneracy completely.Comment: 17 pages, 7 figures. v2: inclusive signal cross sections at NLO in QCD added; new comment on sensitivity of the analysis to t tbar h process. Matches version accepted by JHE

Higgs characterisation at NLO in QCD: CP properties of the top-quark Yukawa interaction

At the LHC the CP properties of the top-quark Yukawa interaction can be probed through Higgs production in gluon fusion or in association with top quarks. We consider the possibility for both CP-even and CP-odd couplings to the top quark to be present, and study CP-sensitive observables at next-to-leading order (NLO) in QCD, including parton-shower effects. We show that the inclusion of NLO corrections sizeably reduces the theoretical uncertainties, and confirm that di-jet correlations in $H+2$ jet production through gluon fusion and correlations of the top-quark decay products in $t\bar tH$ production can provide sensitive probes of the CP nature of the Higgs interactions.Comment: 18 pages, 9 figures, 12 tables; v2: references added, version to appear in EPJ

Double fermiophobic Higgs boson production at the LHC and LC

We consider the phenomenology of a fermiophobic Higgs boson (h_f) at the Large Hadron Collider (LHC) and a e+e- Linear Collider (LC). At both machines the standard production mechanisms which rely on the coupling h_fVV (V=W,Z) can be very suppressed at large tan beta. In such cases the complementary channels pp to H^\pm h_f, A^0 h_f and e+e- to A^0 h_f offer promising cross-sections. Together with the potentially large branching ratios for H^\pm to h_fW* and A^0 to h_fZ*, these mechanisms would give rise to double h_f production, leading to signatures of gamma gamma gamma gamma, gamma gamma VV and VVVV.Comment: 19 pages, 9 figures, expanded discussion, fig.1 changed slightly, version to appear in Phys.Rev.

A Contribution to the study of the distribution of <i>Medicago-Sinorhizobium</i> symbiosis in Sardinia (Italy)

The paper summarizes the results of a Medicago-Sinorhizobium germplasm survey and collection carried out in the island of Sardinia (Italy) in 1998/99 and subsequent laboratory isolation of microbial strains, soil sample analyses and determination of Medicago species. According to a stratified sampling methodology, the major ecological characteristics of island's habitats were taken into account, collecting and surveying mostly in natural or semi-natural habitats (no roadside sites nor cultivated fields were sampled). Forty-six sites, widely distributed in semi-natural representative areas of Sardinia, ranging from sea level to above 1000 m asl, were sampled and 24 were surveyed to gather additional data on species distribution. Root nodules were collected from 15 species (13 annuals) out of the total 21 Medicago species recorded in Sardinia. Isolation of root nodule bacteria accessions and identification of 29 strains were achieved. A total number of 17 species were surveyed and mapped. The present study gives a first contribution to the knowledge of the present distribution of the species of the genus Medicago in Sardinia with special concern to the species recorded or sampled during the survey and highlights the presence of Medicago biodiversity hot spots

Prevalence of Chronic Cancer and No-Cancer Pain in Elderly Hospitalized Patients: Elements for the Early Assessment of Palliative Care Needs

Summary: Background: We studied prevalence of chronic pain, related or not to cancer, in elderly patients, its correlation with socio-clinical factors, and its effects on daily living, to estimate feasibility of an early assessment of palliative care needs in a non-specialist hospital setting. Methods: In this prospective study, a questionnaire concerning pain and multidimensional assessment tools were administered to patients consecutively admitted to a Department of Internal Medicine comprising a Stroke Unit. Results: One hundred patients were recruited, 38 of whom experiencing pain, chronic in 26 patients (68%). A total of 34.3% of patients with pain and 12.5% of patients without pain suffered from depression (P = 0.013). Depressed patients showed significantly higher median values in all Brief Pain Inventory (BPI) scores and items. Depressed patients also obtained less pain relief from therapies. Patients with mild dementia showed, significantly or as a trend, a higher median least, average and "pain right now" pain values. Worst pain values in the previous 24 h increased with age. Only 42% of patients reported to be on pain therapy upon admission to hospital, whereas 62% were undergoing treatment at the time of discharge. A correlation was found between the pain value and the level of interference with daily activities. Pain was mentioned in the discharge letter in 36% of cases. Conclusion: Pain is a critical underestimated problem in elderly patients. A timely systematic evaluation of the pain would call attention to palliative care needs and reduce the negative effects of uncontrolled pain on the quality of life. Keywords: Pain assessment, Pain prevalence, Elderly patients, Pain and depression, Pain and activities of daily livin

Summary report of MINSIS workshop in Madrid

Recent developments on tau detection technologies and the construction of high intensity neutrino beams open the possibility of a high precision search for non-standard {\mu} - {\tau} flavour transition with neutrinos at short distances. The MINSIS - Main Injector Non-Standard Interaction Search- is a proposal under discussion to realize such precision measurement. This document contains the proceedings of the workshop which took place on 10-11 December 2009 in Madrid to discuss both the physics reach as well as the experimental requirements for this proposal.Comment: Proceedings of the MINSIS Workshop, Dec 10-11, 2009 in Madrid. 15 pages late

Minimal Dark Matter predictions for galactic positrons, anti-protons, photons

We present the energy spectra of the fluxes of positrons, anti-protons and photons generated by Dark Matter annihilations in our galaxy, as univocally predicted by the model of Minimal Dark Matter. Due to multi-TeV masses and to the Sommerfeld enhancement of the annihilation cross section, distinctive signals are generated above the background, even with a modest astrophysical boost factor, in the range of energies soon to be explored by cosmic ray experiments.Comment: 16 pages, 6 figures, 3 tables of fit parameters. v3: in an addendum at page 17 we show that the Minimal Dark Matter prediction agrees with the anomaly in the positron spectrum announced by the PAMELA collaboratio

Lepton-pair production in association with a bbˉb\bar{b} pair and the determination of the WW boson mass

We perform a study of lepton-pair production in association with bottom quarks at the LHC based on the predictions obtained at next-to-leading order in QCD, both at fixed order and matched with a QCD parton shower. We consider a comprehensive set of observables and estimate the associated theoretical uncertainties by studying the dependence on the perturbative QCD scales (renormalisation, factorisation and shower) and by comparing different parton-shower models (Pythia8 and Herwig++) and matching schemes (MadGraph5_aMC@NLO and POWHEG). Based on these results, we propose a simple procedure to include bottom-quark effects in neutral-current Drell-Yan production, going beyond the standard massless approximation. Focusing on the inclusive lepton-pair transverse-momentum distribution $p_{\bot}^{l^+l^-}$, we quantify the impact of such effects on the tuning of the simulation of charged-current Drell-Yan observables and the $W$-boson mass determination.Comment: 47 pages, 29 figures, 1 tabl