arXiv subjects
Publications and source records attributed to Lincoln Wolfenstein.
Two sources of strong phases in the decays $B$ to $ππ$ are identified: (1) "quasi-elastic scattering" corresponding to intermediate states like $ππ$ and $ρρ$, (2) ``$c\bar{c}$'' corresponding to intermediate states like $D\bar{D}$ and $D^{*}\bar{D}^{*}$. Possibilities of using data to identify these two sources are discussed and illustrated. Present data suggests both sources may be significant.
Study of the neutrinoless double beta decay and searches for the manifestation of the neutrino mass in ordinary beta decay are the main sources of information about the absolute neutrino mass scale, and the only practical source of information about the charge conjugation properties of the neutrinos. Thus, these studies have a unique role in the plans for better understanding of the whole fast expanding field of neutrino physics.
The scattering amplitude of D Pi at the energy of the B mass can be calculated using Regge theory. Recent papers have used this to calculate the final state strong phases in the decays B to D Pi. It is argued that while the Regge amplitude can yield an absorption correction to the decay rate, it is not useful for determining the strong phase.
CP violation is now measured by three numbers: εand {ε{^{\prime} for the K^{0} system and sin2βfor B^{0}. A future measurement of the analogue of {ε{^{\prime} for the B system would end any possibility of a Superweaklike Theory. Future frontiers in CP violation are briefly discussed.
The constraints on the value of the CKM phase gamma that may be achieved by prospective measurements of sin(2 beta) and sin(2 beta + gamma) are discussed. Significant constraints require quite small errors, and may depend on assumptions about strong phases. The measurement of sin(2 beta + gamma) combined with other experiments could provide valuable limits on new physics in Bd-Bdbar mixing.
Three possibilities for the origin of CP violation are discussed: (1) the Standard Model in which all CP violation is due to one parameter in the CKM matrix, (2) the superweak model in which all CP violation is due to new physics and (3) the Standard Model plus new physics. A major goal of B physics is to distinguish these possibilities. CP violation implies time reversal violation (TRV) but direct evidence for TRV is difficult to obtain.
A qualitative understanding of the day-night asymmetry for solar neutrinos is provided. The greater night flux in nu_e is seen to be a consequence of the fact that the matter effect in the sun and that in the earth have the same sign. It is shown in the adiabatic approximation for the sun that for all values of the mixing angle theta_V between 0 and pi/2, the night flux of neutrinos is greater than the day flux. Only for small values of theta_V where the adiabatic approximation badly fails does the sign of the day-night asymmetry reverse.
It has been pointed out by Gronau and Rosner that the angle gamma of the unitarity triangle could be determined by combining future results on B_s and B_d decays to K pi. Here we show that it is important to include in the analysis the information on the phase beta which will be determined in the near future. Omitting this information could lead to an error as large as 8 degrees in gamma.
Recently, the Babar and Belle collaborations have reported their first measurements of the CP-violating asymmetry in Bd --> psi KS, and more precise results will follow soon. We discuss what a future evidence for small sin(2 beta) could mean, contrasting the usual possibility of new physics in the Bd system, with the interesting alternative that the new physics effects are confined to the kaon system.
It is expected that, within the next three years, the determination of the CKM matrix elements with the least theoretical uncertainty will arise from the measurements of CP violation in B_d --> J/ψK_S decays and from Bs-Bsbar mixing. If there is significant new physics in Bs-Bsbar mixing, then those experiments will not yield the correct values for the CKM matrix elements. As a result, a qualitative signal of new physics may appear in the CP violation of decays like B_d --> pi+ pi-.
In general there are nine observables in the decay of a B meson to two vector mesons defined in terms of polarization correlations of these mesons. Only six of these can be detected via the subsequent decay angular distributions because of parity conservation in those decays. The remaining three require the measurement of the spin polarization of one of the decay products.
Contributions to B - \bar B mixing from physics beyond the standard model may be detected from CP-violating asymmetries in B decays. There exists the possibility of large new contributions that cannot be detected by first generation experiments because of a discrete ambiguity. Some possible strategies for resolving this are discussed.
The symmetry between quarks and leptons suggests that neutrinos should have mass. As embodied in the grand unified theory SO(10) this yields masses that can only be detected by neutrino oscillations. Such oscillations could be very important for supernova physics. Present observations of solar neutrinos when combined with standard solar model calculations imply particular parameters for neutrino masses and mixings. If the solar model is somewhat relaxed quite different possibilities emerge, which yield very different predictions for future experiments.
A recent experiment LSND at Los Alamos has provided\cite{1} an indication of $\overlineν_μ - \overlineν_e$ oscillations with $Δm^2$ of order 1ev$^2$ or greater and $\sin^2 2 θ_{e μ}$ between $2 \times 10^{-3}$ and $10^{2}$. Such a value of $Δm^2$ for $ν_μ - ν_e$ oscillations was not expected in the standard see-saw model\cite{2} suggested by SO(10) with a large mass hierarchy because it leads to too large a value of $m(ν_τ)$ to fit cosmological constraints. Furthermore within that model the LSND result is inconsistent with the indications of oscillations from both atmospheric neutrinos\cite{3} and solar neutrinos.\cite{4}
The existence of $D^0-\overline{D^0}$ mixing at a detectable level requires new physics, which effectively yields a $Δc = 2$ superweak interaction. In general this interaction may involve significant CP violation. For small values of the mixing it may be much easier to detect the CP-violating part of the mixing than the CP-conserving part.
The neutrino deficits observed in four solar neutrino experiments, relative to the theoretical predictions, have led to fresh insights into neutrino and solar physics. Neutrino emission from distant, energetic astronomical systems may form the basis for a new field of astronomy. Additional experiments are needed to test explanations of the solar neutrino deficits and to allow the detection of more distant sources.
In the most general two-Higgs doublet model with an approximate family symmetry and CP violation being originated solely from the relative phase of two vacuum expectation values, CP asymmetry in the decay $b\rightarrow sγ$ may arise from the CP violation of the charged Higgs boson interactions with fermions. This asymmetry may be larger than in the standard model and can lie between $10^{-2}$ and $10^{-1}$. The decay rate of $b\rightarrow sγ$ is allowed to be smaller or larger than in the standard model
Assuming CP violation arises solely through the Higgs potential, we develop the most general two-Higgs doublet model. There is no discrete symmetry that distinguishes the two Higgs bosons. It is assumed that an approximate global family symmetry sufficiently suppresses flavor-changing neutral scalar interactions. In addition to a CKM phase, neutral boson mixing, and superweak effects, there can be significant CP violation due to charged Higgs boson exchange. The value of $ε'/ε$ due to this last effect could be as large as in the standard model.