RESUMEN
We suggest searching for the charged Higgs boson at the Large Hadron Collider (LHC) via cgâbH^{+}âbtb[over ¯]. In the general two Higgs doublet model, extra top Yukawa couplings ρ_{tc} and ρ_{tt} can drive the disappearance of antimatter from the Universe, while c[over ¯]bH^{+} and t[over ¯]bH^{+} couple with strength ρ_{tc}V_{tb} and ρ_{tt}V_{tb}, respectively. For ρ_{tc},ρ_{tt}â¼0.5, and m_{H^{+}}â¼300-500 GeV, evidence could emerge from LHC run 2 data at hand and discovery by adding run 3 data in the near future.
RESUMEN
Weakly interacting KâπX(0) emission with mX(0)â mπ(0) is out of sight of the current K+âπ+ νν study, but it can be sensed by the KLâπ(0)νν search. This evades the usual Grossman-Nir bound of B(KLâπ(0)νν)<1.4×10(-9); thus, the KOTO experiment is already starting to probe new physics. An intriguing possibility is the Z' gauge boson of a weak leptonic force that couples to Lµ-Lτ (the difference between the muon and tauon numbers), which may explain the long-standing "muon g-2" anomaly, but is constrained by νµNâνµNµ+ µ- scattering to mZ'â²400 MeV. An explicit model for KâπZ' is given, which illustrates the link between rare kaon and BâKµ+ µ-, K(*)νν decays. Complementary to these searches and future lepton experiments, the LHC might discover the scalar boson Ï responsible for light mZ' generation via ÏâZ'Z'â2(µ+ µ-).
RESUMEN
RATIONALE AND OBJECTIVES: To investigate the value of dual-energy spectral computed tomography (DESCT) in the quantitative differentiation between pulmonary malignant masses and inflammatory masses. MATERIALS AND METHODS: This study was an institutional review board-approved study, and written informed consent was obtained from all patients. Sixty patients with 35 lung cancers and 25 inflammatory masses underwent DESCT scan during arterial phase (AP) and venous phase (VP). CT numbers of net enhancement in 70 keV monochromatic images in central and peripheral regions of masses and their differences (dCT) were measured. Iodine concentrations in the two regions were measured and normalized to the aorta as normalized iodine concentrations (NICs). The slopes of spectral attenuation curves (λHU) in the two regions were also calculated. The two-sample t test was used to compare quantitative parameters. Receiver operating characteristic (ROC) curves were generated to calculate sensitivity and specificity. RESULTS: CT numbers of net enhancement and NICs in central regions, and λHU values both in the central and peripheral region of lung cancers were significantly lower than those of inflammatory masses during AP and VP. On the other hand, the dCT values of lung cancers were higher than that of inflammatory masses. NIC value in the central regions in VP had the highest sensitivity (86%) and specificity (100%) in differentiating malignant masses from inflammatory masses. CONCLUSIONS: DESCT imaging with quantitative parameters such as CT numbers of 70 keV monochromatic images, NIC, and λHU may be a new method for differentiating lung cancers from inflammatory masses.
Asunto(s)
Enfermedades Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Inflamación/diagnóstico por imagen , Yopamidol , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Intensificación de Imagen Radiográfica , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
We study the effect from a sequential fourth generation quark on penguin-dominated two-body nonleptonic B meson decays in the next-to-leading order perturbative QCD formalism. With an enhancement of the color-suppressed tree amplitude and possibility of a new CP phase in the electroweak penguin amplitude, we can account better for A(CP)(B(0)-->K+ pi-)-A(CP)(B+-->K+ pi0). Taking |V(t's)V(t'b)| approximately 0.02 with a phase just below 90 degrees, which is consistent with the b-->sl+ l- rate and the B(s) mixing parameter Deltam(B)(s), we find a downward shift in the mixing-induced CP asymmetries of B(0)-->K(S)(pi 0) and phi(K)(S). The predicted behavior for B(0)-->rho(0)(K)(S) is opposite.
RESUMEN
We show in a model independent way that, within the standard model, the deviation in the measured B(d){0}-B[over](d){0} mixing phase caused by pollution from another amplitude is always less in magnitude, and has the same sign as, the weak phase of the polluting amplitude. The exception is to have large destructive interference between the two amplitudes: any deviation larger than a few degrees is only possible if the observed decay rate results from fine-tuned cancellations between significantly larger amplitudes. This is unlikely given our understanding of B decays. Even if the deviation reduces to a few degrees in the future, new physics would still likely be implied.
RESUMEN
Direct CP violation in B0 --> K+ pi- decay has emerged at the -10% level, but the asymmetry in B+ --> K+ pi0 mode is consistent with zero. This difference points towards possible new physics in the electroweak penguin operator. We point out that a sequential fourth generation, with sizable V(t' s)* V(t' b) and near maximal phase, could be a natural cause. We use the perturbative QCD factorization approach for B --> Kpi amplitudes. While the B0 --> K+ pi- mode is insensitive to t', we critically compare t' effects on direct CP violation in B+ --> K+ pi0 with b --> sl+ l- and B(s) mixing. If the K+ pi0 - K+ pi- asymmetry difference persists, we predict sin2phi(Bs) to be negative.
RESUMEN
Two recent experimental developments, when combined, may have far-reaching implications. S(phiK(S))<0, if confirmed, would imply large s-b mixing, a new CP phase, and right-handed dynamics. Large Deltam(B(s)) would be likely, making the B(s) program at hadron machines difficult. Reconstruction of B vertex from K(S) at B factories, as shown by BaBar's first measurement of SK(S)(pi(0)), makes SK(S)(pi(0)gamma) in B-->K(*0)gamma accessible. This would be a boon for B factory upgrades. Supersymmetric Abelian flavor symmetry, independently motivated, can realize all of this with a light sb(1) squark. B factory and collider studies of flavor, CP and supersymmetry, may not be what we had expected.