Electroweak radiative corrections to single Higgs-boson production in e+e- annihilation

We have calculated the complete electroweak O(alpha) radiative corrections to the single Higgs-boson production processes e+ e- --> nu_l anti-nu_l H (l=e,mu,tau) in the electroweak Standard Model. Initial-state radiation beyond O(alpha) is included in the structure-function approach. The calculation of the corrections is briefly described, and numerical results are presented for the total cross section. In the G_mu scheme, the bulk of the corrections is due to initial-state radiation, which affects the cross section at the level of -7% at high energies and even more in the ZH threshold region. The remaining bosonic and fermionic corrections are at the level of a few per cent. The confusing situation in the literature regarding differing results for the fermionic corrections to this process is clarified.Comment: 11 pages, latex, 7 postscript files, some references added, final version to appear in Phys.Lett.

Electroweak corrections to e+ e- -> f anti-f H

Some of the most interesting Higgs-production processes at future e+ e- colliders are of the type e+ e- -> f anti-f H. We present a calculation of the complete O(alpha) corrections to these processes in the Standard Model for final-state neutrinos and top quarks. Initial-state radiation beyond O(alpha) at the leading-logarithmic level as well as QCD corrections are also included. The electroweak corrections turn out to be sizable and reach the order of +/-10% and will thus be an important part of precise theoretical predictions for future e+ e- colliders.Comment: 4 pages, LaTeX, 4 postscript figures, talk given at Loops and Legs 2004, 7th DESY Workshop on Elementary Particle Theory, Zinnowitz, German

Top Squarks and Bottom Squarks in the MSSM with Complex Parameters

We present a phenomenological study of top squarks (~t_1,2) and bottom squarks (~b_1,2) in the Minimal Supersymmetric Standard Model (MSSM) with complex parameters A_t, A_b, \mu and M_1. In particular we focus on the CP phase dependence of the branching ratios of (~t_1,2) and (~b_1,2) decays. We give the formulae of the two-body decay widths and present numerical results. We find that the effect of the phases on the (~t_1,2) and (~b_1,2) decays can be quite significant in a large region of the MSSM parameter space. This could have important implications for (~t_1,2) and (~b_1,2) searches and the MSSM parameter determination in future collider experiments. We have also estimated the accuracy expected in the determination of the parameters of ~t_i and ~b_i by a global fit of the measured masses, decay branching ratios and production cross sections at e^+ e^- linear colliders with polarized beams. Analysing two scenarios, we find that the fundamental parameters apart from A_t and A_b can be determined with errors of 1% to 2%, assuming an integrated luminosity of 1 ab^-1 and a sufficiently large c.m.s. energy to produce also the heavier ~t_2 and ~b_2 states. The parameter A_t can be determined with an error of 2 - 3%, whereas the error on A_b is likely to be of the order of 50%.Comment: 31 pages, 8 figures, comments and references added, conclusions unchanged; version to appear in Phys. Rev.

Electroweak radiative corrections to e+ e- -> nu nubar H

The complete electroweak O(alpha) radiative corrections to the Higgs-boson production processes e+ e- -> nu_l anti-nu_l H (l=e,mu,tau) are calculated in the electroweak Standard Model. For e+ e- -> nu_e anti-nu_e H, where ZH production and W-boson fusion contribute, both production channels are added coherently. The calculation of the corrections is described in some detail including, in particular, the treatment of the Z-boson resonance in the ZH-production channel. The discussion of numerical results focusses on the total cross section as well as on angular and energy distributions of the Higgs boson. In the Gmu-scheme, the bulk of the corrections is due to initial-state radiation. The corrections turn out to reduce the total cross section by \sim 10% for high energies, where the W-boson fusion dominates. In this region, the corrections depend only weakly on the energy and the production angle of the Higgs boson. Based on an analysis of the leading universal corrections, a simple improved Born approximation is introduced. This approximation describes the corrected cross section within about 3%.Comment: 35 pages, Latex, 17 postscript file

Tau-Sleptons and Tau-Sneutrino in the MSSM with Complex Parameters

We present a phenomenological study of tau-sleptons stau_1,2 and tau-sneutrino in the Minimal Supersymmetric Standard Model with complex parameters A_tau, mu and M_1. We analyse production and decays of stau_1,2 and tau-sneutrino at a future e^+ e^- collider. We present numerical predictions for the important decay rates, paying particular attention to their dependence on the complex parameters. The branching ratios of the fermionic decays of stau_1 and tau-sneutrino show a significant phase dependence for tan(beta) < 10. For tan(beta) > 10 the branching ratios for the stau_2 decays into Higgs bosons depend very sensitively on the phases. We show how information on the phase phi(A_tau) and the other fundamental stau parameters can be obtained from measurements of the stau masses, polarized cross sections and bosonic and fermionic decay branching ratios, for small and large tan(beta) values. We estimate the expected errors for these parameters. Given favorable conditions, the error of A_tau is about 10% to 20%, while the errors of the remaining stau parameters are in the range of approximately 1% to 3%. We also show that the induced electric dipole moment of the tau-lepton is well below the current experimental limit.Comment: LaTex, 25 pages, 11 figures (included); v2: extended discussion on error determination, version to appear in Phys.Rev.

Presenting a simplified assistant tool for breast cancer diagnosis in mammography to radiologists

This paper proposes a method to simplify a computational model from logistic regression for clinical use without computer. The model was built using human interpreted featrues including some BI-RADS standardized features for diagnosing the malignant masses. It was compared with the diagnosis using only assessment categorization from BI-RADS. The research aims at assisting radiologists to diagnose the malignancy of breast cancer in a way without using automated computer aided diagnosis system

Letter of interest for a neutrino beam from Protvino to KM3NeT/ORCA

The Protvino accelerator facility located in the Moscow region, Russia, is in a good position to offer a rich experimental research program in the field of neutrino physics. Of particular interest is the possibility to direct a neutrino beam from Protvino towards the KM3NeT/ORCA detector, which is currently under construction in the Mediterranean Sea 40 km offshore Toulon, France. This proposal is known as P2O. Thanks to its baseline of 2595 km, this experiment would yield an unparalleled sensitivity to matter effects in the Earth, allowing for the determination of the neutrino mass ordering with a high level of certainty after only a few years of running at a modest beam intensity of ≈ 90 kW. With a prolonged exposure (≈1500 kWyear), a 2σ sensitivity to the leptonic CP-violating Dirac phase can be achieved. A second stage of the experiment, comprising a further intensity upgrade of the accelerator complex and a densified version of the ORCA detector (Super-ORCA), would allow for up to a 6σ sensitivity to CP violation and a 10º−17º resolution on the CP phase after 10 years of running with a 450 kW beam, competitive with other planned experiments. The initial composition and energy spectrum of the neutrino beam would need to be monitored by a near detector, to be constructed several hundred meters downstream from the proton beam target. The same neutrino beam and near detector set-up would also allow for neutrino-nucleus cross section measurements to be performed. A short-baseline sterile neutrino search experiment would also be possible

Miniband-related 1.4–1.8 μm luminescence of Ge/Si quantum dot superlattices

The luminescence properties of highly strained, Sb-doped Ge/Si multi-layer heterostructures with incorporated Ge quantum dots (QDs) are studied. Calculations of the electronic band structure and luminescence measurements prove the existence of an electron miniband within the columns of the QDs. Miniband formation results in a conversion of the indirect to a quasi-direct excitons takes place. The optical transitions between electron states within the miniband and hole states within QDs are responsible for an intense luminescence in the 1.4–1.8 µm range, which is maintained up to room temperature. At 300 K, a light emitting diode based on such Ge/Si QD superlattices demonstrates an external quantum efficiency of 0.04% at a wavelength of 1.55 µm

Early extracorporeal CPR for refractory out-of-hospital cardiac arrest

BACKGROUNDExtracorporeal cardiopulmonary resuscitation (CPR) restores perfusion and oxy-genation in a patient who does not have spontaneous circulation. The evidencewith regard to the effect of extracorporeal CPR on survival with a favorable neu-rologic outcome in refractory out-of-hospital cardiac arrest is inconclusive.METHODSIn this multicenter, randomized, controlled trial conducted in the Netherlands, weassigned patients with an out-of-hospital cardiac arrest to receive extracorporealCPR or conventional CPR (standard advanced cardiac life support). Eligible patientswere between 18 and 70 years of age, had received bystander CPR, had an initialventricular arrhythmia, and did not have a return of spontaneous circulationwithin 15 minutes after CPR had been initiated. The primary outcome was sur-vival with a favorable neurologic outcome, defined as a Cerebral PerformanceCategory score of 1 or 2 (range, 1 to 5, with higher scores indicating more severedisability) at 30 days. Analyses were performed on an intention-to-treat basis.RESULTSOf the 160 patients who underwent randomization, 70 were assigned to receiveextracorporeal CPR and 64 to receive conventional CPR; 26 patients who did notmeet the inclusion criteria at hospital admission were excluded. At 30 days, 14 pa-tients (20%) in the extracorporeal-CPR group were alive with a favorable neuro-logic outcome, as compared with 10 patients (16%) in the conventional-CPR group(odds ratio, 1.4; 95% confidence interval, 0.5 to 3.5; P = 0.52). The number of seri-ous adverse events per patient was similar in the two groups.CONCLUSIONSIn patients with refractory out-of-hospital cardiac arrest, extracorporeal CPR andconventional CPR had similar effects on survival with a favorable neurologic out-come. (Funded by the Netherlands Organization for Health Research and Develop-ment and Maquet Cardiopulmonary [Getinge]; INCEPTION ClinicalTrials.govnumber, NCT03101787.)Cardiolog

Mechanical properties of C58 materials and their dependence on thermal treatment

C58 fullerene cages made by electron-impact induced fragmentation of C60 fullerenes have been assembled into several micron thick solid films by low energy cluster beam deposition onto inert substrates held at room temperature under ultrahigh vacuum. The resulting asprepared material, RT-C58, behaves as an amorphous wide-band semiconductor. Nanoindentation was used to measure ist mechanical properties revealing that RT-C58 has a higher elastic modulus E and hardness H than the reference carbon allotropes solid C60 and Highly Ordered Pyrolytic Graphite (HOPG): E(RT-C58) = 14 Gpa and H(RT-C58) = 1.2 Gpa. This effect can be explained by the unique intrinsic functionalization of C58 cages: they comprise reactive surface sites constituted by annelated pentagon rings which give rise to covalently stabilized oligomers, C58C58C58, under our deposition conditions. Annealing, thick RT-C58 films up to 1100 K in ultrahigh vacuum results in HAT-C58, a new material with considerably modified electronic and vibra