The Spherical Neutral Detector (SND) is an experiment for e+e− annihilation study at low energies 0.2−2 GeV. The light quark anti−quark bound states are the main subject of study at these energies. ...They express themselves as resonances in the e+e− hadronic cross sections. Hadronic cross sections could be recalculated to hadronic vacuum polarization (HVP). The Standard Model predictions today are limited by HVP which is not calculable with modern QCD theory. In this talk we present the review of the hadronic cross sections measurements at SND and new measurements: e+e− → π+π−, π0γ, π+π−π0, ωπ0, K+K−η, η, KsKLπ0, π+π−π0η, ωπ0η e.t.c.
We analyze a 37 pb−1 data sample collected with the SND detector at the VEPP-2000 e+e− collider in the center-of-mass energy range 1.05–2.00 GeV and present an updated measurement of the ...e+e−→ωπ0→π0π0γ cross section. In particular, we correct the mistake in radiative correction calculation made in our previous measurement based on a part of the data. The measured cross section is fitted with the vector meson dominance model with three ρ-like states and used to test the conserved vector current hypothesis in the τ−→ωπ−ντ decay.
Study of the Form Factor Using the SND Detector Achasov, M. N.; Baikov, A. A.; Barnyakov, A. Yu ...
Bulletin of the Lebedev Physics Institute,
2021/3, Letnik:
48, Številka:
3
Journal Article
Recenzirano
In this paper, we present the form factor
measurement in the virtual photon mass range 1 GeV <
< 2 GeV in the
process. Measurements are based on the data acquired by the SND detector at the VEPP-2000
...collider in Novosibirsk. The obtained form factor is approximated in the vector meson dominance (VMD) model. The joint fitting of the form factor obtained in the SND and NA60 experiments is also performed.
Gravitational light deflection, predicted by general relativity, is a fascinating phenomenon with numerous important applications in astronomy, astrophysics and cosmology. At first sight, there is no ...analogous effect in electrodynamics because Maxwell's equations are linear and, therefore, a photon does not interact with the electromagnetic field of an alleged deflector charge. However, quantum electrodynamical corrections bring nonlinearities in the theory. As a result, in a external electromagnetic field, the vacuum acquires an effective refractive index. One immediate consequence of this effective refractive index is the deflection of light in a Coulomb field. In this paper, the authors use light bending by a Coulomb field as a pedagogical tool for a discussion of the electrodynamical analogue of the general relativistic Aichelburg-Sexl ultraboost. (Contains 1 figure.)
Recent results from the SND detector Korol, A. A.; Achasov, M. N.; Barnyakov, A. Yu ...
EPJ Web of Conferences,
01/2017, Letnik:
142
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Recent results of the SND detector experiments are presented. Data were taken at the VEPP-2000 and the VEPP-2M e+e− colliders in the Novosibirsk in the c.m. energy ranges from 0.3 to 2.00 GeV. ...Integrated luminosity used are 70pb-1 and 25pb-1 respectively. The cross sections of the e+e− → π0γ, K+K−, ωπ0, π+π−π0η, ωη, ωηπ0 processes has been measured.
New results on exclusive hadron production in e+e− annihilation obtained in experiments with the SND detector at the VEPP-2M and VEPP-2000 e+e− colliders are presented.
The process e+e−→π+π−π0η is studied in the center-of-mass energy region below 2 GeV with the SND detector at the VEPP-2000 e+e− collider. The following four intermediate states contribute to this ...process: ωη, ϕη, a0(980)ρ, and a structureless π+π−π0η state. We measure the total e+e−→π+π−π0η cross section and the cross sections for its components: ωη, ϕη, and a sum of a0(980)ρ and the structureless state. Our results are in agreement with previous measurements and have comparable or better accuracies.
This is a popular lecture about the history of gravitational wave research. Without any doubt, the discovery of gravitational waves is the most important event in the physics of the last decade along ...with the discovery of the Higgs boson. This landmark discovery is another confirmation of the general theory of relativity, on the basis of which Albert Einstein predicted the existence of gravitational waves in 1916. However, the history of gravitational wave research includes, besides Einstein, many other important players. The author thanks Mikhail Korobko for pointing out the inaccuracy in the first version of the manuscript and Olga Chashchina for her kind help with the text of the manuscript. Any remaining errors and inaccuracies are solely the fault of the author.
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