Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm.

We present a new measurement of the positive muon magnetic anomaly, a_{µ}≡(g_{µ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{µ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{µ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{µ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision.

Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm.

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{µ}≡(g_{µ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{µ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both µ^{+} and µ^{-}, the new experimental average of a_{µ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

New precise measurement of the pion weak form factors in pi+-->e+ nugamma decay.

We have measured the pi+-->e+ nugamma branching ratio over a wide region of phase space, based on a total of 65 460 events acquired using the PIBETA detector. Minimum-chi2 fits to the measured (E(e+), E(gamma) energy distributions result in the weak form factor value of F(A)=0.0119(1) with a fixed value of F(V)=0.0259. An unconstrained fit yields F(V)=0.0258(17) and F(A)=0.0117(17). In addition, we have measured a=0.10(6) for the dependence of F(V) on q2, the e+ nu pair invariant mass squared, parametrized as F(V)(q2)=F(V)(0)(1+aq(2)). The branching ratio for the kinematic region E(gamma)>10 MeV and theta(e(+)gamma)>40 degrees is measured to be B(expt)=73.86(54)x10(-8). Earlier deviations we reported in the high-E(gamma)-low-E(e+) kinematic region are resolved without a tensor term. We also derive new values for the pion polarizability alpha(E)=2.78(10)x10(-4) fm3 and neutral pion lifetime tau(pi0)=(8.5+/-1.1)x10(-17) s.

Precise measurement of the pi+-->pi0 e+nu branching ratio.

Using a large acceptance calorimeter and a stopped pion beam we have made a precise measurement of the rare pi(+)-->pi(0)e(+)nu (pi(beta)) decay branching ratio. We have evaluated the branching ratio by normalizing the number of observed pi(beta) decays to the number of observed pi(+)-->e(+)nu (pi(e2)) decays. We find the value of Gamma(pi(+)-->pi(0)e(+)nu)/Gamma(total)=[1.036+/-0.004(stat)+/-0.004(syst)+/-0.003(pi(e2))]x10(-8), where the first uncertainty is statistical, the second systematic, and the third is the pi(e2) branching ratio uncertainty. Our result agrees well with the standard model prediction.

Precise measurement of the pion axial form factor in the pi+-->e+nugamma decay.

We have studied radiative pion decays pi(+)-->e(+)nugamma in three broad kinematic regions using the PIBETA detector and a stopped pion beam. Based on Dalitz distributions of 41 601 events we have evaluated absolute pi-->enugamma branching ratios in the three regions. Minimum chi(2) fits to the integral and differential (E(e(+)),E(gamma)) distributions result in the axial-to-vector weak form factor ratio of gamma identical with F(A)/F(V)=0.443(15), or F(A)=0.0115(4) with F(V)=0.0259. However, deviations from standard model predictions in the high-E(gamma)-low-E(e(+)) kinematic region indicate the need for further theoretical and experimental work.

[Relationship of the value of excess body weight to the blood concentration of cholesterol and triglycerides and the level of the basic hormones regulating lipid metabolism in healthy men 30 to 50 years old]. / Vzaimosviaz' velichiny izbytochnoi massy tela s kontsentratsiei kholesterina, triglitseridov krovi i urovnem osnovnykh gormonov, reguliruiushchikh lipidnyi obmen u zdorovykh muzhchin 30--50 let.

The basal levels of cholesterol (CS), triglycerides (TG), sugar, immunoreactive insulin (IRI), cortisol, testosterone, triiodothyronine (T3) and thyroxine (T4) were compared in 116 healthy males with risk factors of developing coronary heart disease (CHD), aged 45, engaged in administrative activities associated with stress and hypokinesia, with relation to normo-, hyperlipoproteinemia (NLP and HLP) and percentage of excessive body mass (IBM). In NLP as well as in HLP with an increase in IBM a tendency to elevated levels of CS, TG, sugar, IRI was noted, however there was no direct parallelism. In both cases the IBM value within the limits of obesity, I degree, did not influence the concentration of blood cortisol and testosterone. T3 and T4 levels were significantly decreased in males with IBM exceeding the normal one by 25%. They demonstrated the highest content of blood CS, TG and sugar on an empty stomach.

[Role of excessive body weight and hormonal changes in the development of the main types of hyperlipoproteinemia]. / RoL' izbytochnoi masy tela i gormonal'nykh sdvigov v razvitii osnovnykh tipov giperlipoproteidemii.

Hyperlipoproteinemia (HLP) was detected in 67.3% of 118 males without CHD (with the mean age of 44.7 years) engaged in intellectual occupations. The excessive body weight in this group was twice higher, and blood insulin 1.5 times higher, while the STH levels twice lower as compared to patients with normolipoproteinemia (NLP). The mean concentrations of ACTH, cortisol, T3, T4 in both groups were equal and did not exceed normal. In males with the II A type of HLP versus those with the II B and IV types, the excessive body weight and blood cortisol content were 1.5 times as low but testosterone levels were 1.5 times as high and approached those in individuals with NLP.

[The efficacy of outpatient examination of the female population for the early diagnosis of breast cancer]. / Ob éffektivnosti dispanserizatsii zhenskogo naseleniia s tsel'iu rannei diagnostiki raka molochnoi zhelezy.

The report discusses the data on out-patient follow-up of female population at different stages within 1971-1979. The results were evaluated versus diagnostic and organizational procedures.

[Nosological classification of bokhoror]. / O nozologicheskoi prinadlezhnosti bokhorora.

The results of neurological, pathomorphological and clinic-genealogical studies of vilyuisk encephalitis (VE), a chronic progressive disease of CNS, are presented. The disease is spread in Yakutija in Vilyui river basin (mainly in Vilyuisk and Kobyaisk regions) exclusively among native population and is known there since the middle of the last century. The results obtained suggest that VE (despite the existing opinion on its natural-focal virus etiology) is an ethnic hereditary disease with autosomal recessive type of transmission, is spread in a limited Yakut population by an ancestor effect and gradually gets out of the limits of this population at the expense of migration. According to its clinical symptoms and pathomorphological substrate of this main neurological syndrome (peculiar lower spastic paraparesis as a result of systemic ascending degeneration of lateral corticospinal tract of spinal cord), VE belongs to hereditary heterogenous group of diseases which are referred to Strümpell's spastic paraplegia. VE is different from the diseases of this group by the occurrence of cases with very rapid progressing and characteristic brain damages. To prevent further VE accumulation, it is necessary to concentrate efforts on biochemical and neurological studies in search of reliable tests for early detection of heterozygotes. Taking into account the hereditary nature of VE, its ethnic limitations and nosological self-dependence, it is expedient to designate the disease by its local name "bokhoroor".