2,758 research outputs found
Measurement of the inclusive φ cross-section in pp collisions at √s=7 TeV
No full textThe cross-section for inclusive φ meson production in pp collisions at a centre-of-mass energy of √s = 7 TeV has been measured with the LHCb detector at the Large Hadron Collider. The differential cross-section is measured as a function of the φ transverse momentum pT and rapidity y in the region 0.6< pT <5.0 GeV/c and 2.44< y <4.06. The cross-section for inclusive φ production in this kinematic range is σ(pp→φX)=1758±19(stat) +43−14(syst)±182(scale) μb, where the first systematic uncertainty depends on the pT and y region and the second is related to the overall scale. Predictions based on the Pythia 6.4 generator underestimate the cross-section
Analysis of methods for calculating spur gear for deep contact strength
No full textSpur gear is an integral part of transport and technological machines structure. To increase the load ability of the spur gear, chemical heat treatment of the working cogs surfaces is used. Spur gear with chemical heat treatment must be checked for deep contact strength. The article analyzes various methods (according to GOST 21354-87, methods using the generalized criterion of the limit state for structurally inhomogeneous material by Lebedev-Pisarenko, methods from the handbook describing reducers of power machines etc.) for calculating spur and helical gearing for deep contact strength. The author presents all necessary formulas and graphs for the implementation of each methods, and compares the calculations results of these methods with the results of experimental studies of cemented cylindrical rollers for deep contact destruction
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Measurement of the effective B0s→K+K− lifetime
No full textA measurement of the effective lifetime is presented using approximately 37 pb−1 of data collected by LHCb during 2010. This quantity can be used to put constraints on contributions from processes beyond the Standard Model in the meson system and is determined by two complementary approaches as
τKK=1.440±0.096 (stat)±0.008 (syst)±0.003 (model) ps
Observation of J/ψ-pair production in pp collisions at √s=7 TeV
No full textThe production of J/ψ pairs in proton–proton collisions at a centre-of-mass energy of 7 TeV has been observed using an integrated luminosity of 37.5 pb−1 collected with the LHCb detector. The production cross-section for pairs with both J/ψ in the rapidity range 2 < yJ/ψ < 4.5 and transverse momentum pJ/ψ T <10 GeV/c is σJ/ψJ/ψ =5.1±1.0±1.1 nb, where the first uncertainty is statistical and the second systematic
Measurement of the B0–B0 oscillation frequency Δmd with the decays B0→D−π+ and B0→ J/ψK∗0
No full textThe B
0
–B
0
oscillation frequency Δmd is measured by the LHCb experiment using a dataset corresponding
to an integrated luminosity of 1.0 fb−1
of proton–proton collisions at √
s = 7 TeV, and is found to be
Δmd
=0.5156±0.0051 (stat.)±0.0033 (syst.) ps−1
. The measurement is based on results from analyses
of the decays B
0
→ D
−π
+ (D
−
→ K
+π
−π
−) and B
0
→ J/ψK
∗0
(J/ψ →μ
+μ
−,K
∗0
→ K
+π
−) and
their charge conjugated modes
A History of Russian Literature: from Philologists to Theologians (A review of: Russian Literature of the 19th Century: A Course of Lectures for a Bachelor of Theology Degree: in 2 V. М.: POZNANIE Publishers, 2020.)
No full textThis review presents a detailed analysis of Yu. V. Lebedev’s textbook “Russian Literature of the 19th Century”, written for bachelor of theology degree students. The author of the article considers the new publication in the context of one of the leading branches of modern literary criticism – religious philology. The scope of analysis does not only include the methodology that lies at the basis of the construction of the history of the Russian literature but also the amount and range of the material used by the textbook author to corroborate his hypothesis. On the one hand, the review reveals the efficiency of the approach suggested by Yu. V. Lebedev, on the other hand, it outlines a number of issues, the most important one of which is associated with the need to answer the question whether the content of scientific knowledge will change depending on the target audience. A comparison of two textbooks by Yu. V. Lebedev (“History of Russian Literature of the 19th Century” for students-philologists and “Russian Literature of the 19th Century” for future theologians) shows how the vision of Russian literature is transformed and how the religious paradigm of a humanitarian science is formed. The author makes a conclusion that the ‘adequacy spectrum’ in modern philology is not so much associated with a specific area of research as with the use of various methods and approaches, and the ability to find common ground between them
Criteria of equivalent stress concept
No full textS.13-66At present, there exist more than 200 different criteria (Lebedev Development of the theories of strength in the mechanics of materials. Strength Mater 42(5):578-592, 2010, [1]; Pisarenko, Lebedev Deformation and Strength of Materials under Complex Stress State (in Russ.: Deformirovanie i prochnost' materialov pri slozhnom naprjazhennom sostojanii). Naukowa Dumka, Kiev, 1976, [2]; Yu Unified strength theory and its applications. Springer, Berlin, 2004, [3]).This chapter describes selected criteria which are of the significance for the later chapters and for the systematization. These criteria are written in the same manner and generalized subsequently
Semiconductors V. 39, I. 12
No full textSemiconductors -- December 2005
Volume 39, Issue 12, pp. 1361-1432
ELECTRONIC AND OPTICAL PROPERTIES OF SEMICONDUCTORS
Electroluminescence of Graded-gap Structures with Blocking and Ohmic Contacts
B. S. Sokolovskii, V. I. Ivanov-Omskii, and G. A. Il'chuk
pp. 1361-1368 Full Text: PDF (99 kB)
Mössbauer Study of the Ge Two-Electron Donor Centers in PbSe
E. I. Terukov and É. S. Khuzhakulov
pp. 1369-1370 Full Text: PDF (36 kB)
Electron Exchange between Neutral and Ionized Germanium Centers in PbSe
E. I. Terukov and É. S. Khuzhakulov
pp. 1371-1373 Full Text: PDF (38 kB)
Characterization of Photonic Crystals Based on Opal–Semiconductor Composites by Bragg Reflection Spectroscopy
G. M. Gadzhiev, V. G. Golubev, D. A. Kurdyukov, A. B. Pevtsov, A. V. Sel'kin, and V. V. Travnikov
pp. 1374-1380 Full Text: PDF (89 kB)
SEMICONDUCTOR STRUCTURES, INTERFACES, AND SURFACES
On the Effect of Transverse Quantum Confinement on the Electrical Characteristics of a Submicrometer-Sized Tunnel MOS Structure
M. I. Vexler, I. V. Grekhov, and A. F. Shulekin
pp. 1381-1386 Full Text: PDF (96 kB)
Simulation of the Capacitance–Voltage Characteristics of a Ferroelectric Material
L. S. Berman
pp. 1387-1390 Full Text: PDF (49 kB)
Estimation of the Energy Characteristics of the 3C-SiC/2H-, 4H-, 6H-, and 8H-SiC Heterojunctions
S. Yu. Davydov, A. A. Lebedev, and O. V. Posrednik
pp. 1391-1393 Full Text: PDF (48 kB)
Measurement of Micrometer Diffusion Lengths by Nuclear Spectrometry
N. B. Strokan, A. M. Ivanov, A. A. Lebedev, M. Syväjärvi, and R. Yakimova
pp. 1394-1398 Full Text: PDF (68 kB)
Light-Emitting Si:Er Structures Produced by Molecular-Beam Epitaxy: High-Resolution Photoluminescence Spectroscopy
D. I. Kryzhkov, N. A. Sobolev, B. A. Andreev, D. V. Denisov, Z. F. Krasil'nik, and E. I. Shek
pp. 1399-1402 Full Text: PDF (53 kB)
Electrical Properties of n-GaN/p-SiC Heterojunctions
O. Yu. Ledyaev, A. M. Strel'chuk, A. N. Kuznetsov, N. V. Seredova, A. S. Zubrilov, A. A. Volkova, A. E. Nikolaev, and A. A. Lebedev
pp. 1403-1405 Full Text: PDF (51 kB)
Photosensitivity of Photocells Based on ZnO/CdS/Cu(In, Ga)Se2 Heterostructures and Exposed to gamma-ray Radiation
V. V. Emtsev, Yu. A. Nikolaev, D. S. Poloskin, V. Yu. Rud', Yu. V. Rud', E. I. Terukov, and M. V. Yakushev
pp. 1406-1409 Full Text: PDF (78 kB)
LOW-DIMENSIONAL SYSTEMS
The Tail of Localized States in the Band Gap of the Quantum Well in the In0.2Ga0.8N/GaN System and Its Effect on the Laser-Excited Photoluminescence Spectrum
M. A. Jacobson, D. K. Nelson, O. V. Konstantinov, and A. V. Matveentsev
pp. 1410-1414 Full Text: PDF (69 kB)
PHYSICS OF SEMICONDUCTOR DEVICES
Continuous-wave Lasing of Single-Mode Metamorphic Quantum Dot Lasers for the 1.5-µm Spectral Region
L. Ya. Karachinsky, T. Kettler, N. Yu. Gordeev, I. I. Novikov, M. V. Maximov, Yu. M. Shernyakov, N. V. Kryzhanovskaya, A. E. Zhukov, E. S. Semenova, A. P. Vasil'ev, V. M. Ustinov, N. N. Ledentsov, A. R. Kovsh, V. A. Shchukin, S. S. Mikhrin, A. Lochmann, O. Schulz, L. Reissmann, and D. Bimberg
pp. 1415-1419 Full Text: PDF (72 kB)
The Limiting Energy Resolution of SiC Detectors in Ion Spectrometry
N. B. Strokan, A. M. Ivanov, A. A. Lebedev, M. Syväjärvi, and R. Yakimova
pp. 1420-1425 Full Text: PDF (72 kB)
"Ideal" Static Breakdown in High-Voltage (1 kV) 4H-SiC p–n Junction Diodes with Guard Ring Termination
P. A. Ivanov, I. V. Grekhov, N. D. Il'inskaya, and T. P. Samsonova
pp. 1426-1428 Full Text: PDF (53 kB)
PERSONALIA
Yurii Vasil'evich Shmartsev (On the 75th Anniversary of His Birth)
pp. 1429-1430 Full Text: PDF (82 kB)
Boris Vasil'evich Tsarenkov (On the 75th Anniversary of His Birth)
pp. 1431-1432 Full Text: PDF (57 kB)Archived web conten
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