We propose to measure spin observables AN and ANN in elastic pp scattering by using the transversely polarized proton beam and target at momenta p = 12-45 GeV/c. Existence of both polarized target ...and beam gives us unique possibility to measure AN simultaneously and independently for polarized beam (AB) and target (AT) to carry out and verify experimental measurements of single-spin and double-spin (ANN) measurements in diffractive region.
The STAR collaboration reports a measurement of the transverse single-spin asymmetries, AN , for neutral pions produced in polarized proton collisions with protons ( pp ), with aluminum nuclei ( pAl ...) and with gold nuclei ( pAu ) at a nucleon-nucleon center-of-mass energy of 200 GeV. Neutral pions are observed in the forward direction relative to the transversely polarized proton beam, in the pseudorapidity region 2.7<η<3.8 . Results are presented for π0 s observed in the STAR forward meson spectrometer electromagnetic calorimeter in narrow Feynman x ( xF ) and transverse momentum ( pT ) bins, spanning the range 0.17<xF<0.81 and 1.7<pT<6.0 GeV/c . For fixed xF<0.47 , the asymmetries are found to rise with increasing transverse momentum. For larger xF , the asymmetry flattens or falls as pT increases. Parametrizing the ratio r ( A ) ≡AN ( pA ) / AN ( pp ) =AP over the kinematic range, the ratio r ( A ) is found to depend only weakly on A , with ( P ) =-0.027±0.005 . No significant difference in P is observed between the low- pT region, pT<2.5 GeV/c , where gluon saturation effects may play a role, and the high- pT region, pT>2.5 GeV/c . It is further observed that the value of AN is significantly larger for events with a large- pT isolated π0 than for events with a nonisolated π0 accompanied by additional jetlike fragments. The nuclear dependence r ( A ) is similar for isolated and nonisolated π0 events.
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The only comparative study of the inclusive pion single-spin asymmetries produced in the interactions of the polarized protons and antiprotons in collisions with unpolarized proton was carried out at ...E-704 experiment. Significant asymmetries were found at large xF and middle pT, π+ and π0 asymmetries have positive signs while π− has negative one in the p↑ + p collisions, while in the p¯↑+p interactions the π− and π0 asymmetries have positive signs while π+ has negative sign. Similar experimental study can be done in the SPASCHARM experiment at U-70 accelerator at IHEP for various secondary particles with the use of 16 GeV polarized proton and antiproton beams.
The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π0s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass ...energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π0 pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. Furthermore, the larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale $Q^{2}_{s}$ on the mass number A . A linear scaling of the suppression with A1/3 is observed with a slope of -0.09±0.01.
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We report a new measurement of the production cross section for inclusive electrons from open heavy-flavor hadron decays as a function of transverse momentum (pT) at midrapidity (|y| < 0.7) in p + p ...collisions at √s = 200 GeV. Overall, the result is presented for 2.5 < PT < 10 GeV/c with an improved precision above 6 GeV/c with respect to the previous measurements, providing more constraints on perturbative QCD calculations. Moreover, this measurement also provides a high-precision reference for measurements of nuclear modification factors for inclusive electrons from open-charm and -bottom hadron decays in heavy-ion collisions.
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In this work, we report cumulants of the proton multiplicity distribution from dedicated fixed-target Au+Au collisions at $\sqrt{s_{NN}}$ =3.0 GeV, measured by the STAR experiment in the kinematic ...acceptance of rapidity (y) and transverse momentum (pT) within -0.5 < y < 0 and 0.4 < pT < 2.0 GeV/c. In the most central 0–5% collisions, a proton cumulant ratio is measured to be C4/C2 = –0:85 ± 0:09 (stat:)±0:82 (syst:), which is 2σ below the Poisson baseline with respect to both the statistical and systematic uncertainties. The hadronic transport UrQMD model reproduces our C4/C2 in the measured acceptance. Compared to higher energy results and the transport model calculations, the suppression in C4/C2 is consistent with fluctuations driven by baryon number conservation and indicates an energy regime dominated by hadronic interactions. These data imply that the QCD critical region, if created in heavy-ion collisions, could only exist at energies higher than 3 GeV.
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We report the first measurements of the moments--mean (M), variance (σ(2)), skewness (S), and kurtosis (κ)--of the net-charge multiplicity distributions at midrapidity in Au+Au collisions at seven ...energies, ranging from sqrtsNN=7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net charge, and are sensitive to the location of the QCD critical point. We compare the products of the moments, σ(2)/M, Sσ, and κσ(2), with the expectations from Poisson and negative binomial distributions (NBDs). The Sσ values deviate from the Poisson baseline and are close to the NBD baseline, while the κσ(2) values tend to lie between the two. Within the present uncertainties, our data do not show nonmonotonic behavior as a function of collision energy. These measurements provide a valuable tool to extract the freeze-out parameters in heavy-ion collisions by comparing with theoretical models.
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Experimental results obtained by studying the properties of soft jets in the 4-velocity space at √
s
∼ 2 to 20 GeV are presented. The changes in the mean distance from the jet axis to the jet ...particles, the mean kinetic energy of these particles, and the cluster dimension in response to the growth of the collision energy are consistent with the assumption that quark degrees of freedom manifest themselves in processes of pion-jet production at intermediate energies. The energy at which quark degrees of freedom begin to manifest themselves experimentally in the production of soft pion jets is estimated for the first time. The estimated value of this energy is 2.8 ± 0.6 GeV.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The aim
of the work was to study the clinical case of systemic amyloidosis.
Materials and methods
. Patient Ch., 63 уears old, have admitted to the regional cardiological dispensary with complaints ...of short stabbing pains in the heart, without reaction to nitroglycerin, interruptions in the work of the heart, mainly at night, shortness of breath with little exertion, weakness, swelling of the legs and feet in September 2018. Sick from April 2016, when was dyspnea on exertion. The high level of creatinine, normochromic anemia have detected. In June 2016 chronic pyelonephritis was diagnosed. In August 2018, a right-sided hydrothorax was diagnosed, a pleural puncture was performed.
Results
. Laboratory and instrumental research methods were performed. Based on anamnesis data (normochromic anemia, proteinuria, increased creatinine in the blood), clinical picture, data of instrumental studies (restrictive cardiomyopathy, bilateral hydrothorax) clinical diagnosis was made: systemic amyloidosis the kidneys and heart with chronic kidney disease C5 and chronic heart failure. Histological evidence of amyloid and determination of the variant of amyloidosis by immunohistochemical method was recommended. But the patient died before the study. The histological verification of the diagnosis was carried out at the autopsy.
Conclusion.
This clinical observation is an example of late diagnosis of systemic amyloidosis and postmortal verification of the diagnosis, which is associated with the nonspecific symptoms and the rapidly progressing course of the disease. This case is interesting because amyloidosis proceeded under the guise of other diseases, quickly led to the development of severe heart and renal failure and to the death of the patient before verifying the disease.
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