SND Experiment

Spherical Neutral Detector is a detector for particle physics experiments, successor of the Neutral Detector, created by the team of physicists in the Budker Institute of Nuclear Physics, Russia. There are three major periods in evolution of the SND experiment. Previous experiment with ND has shown that the e+e− annihilation in the final states with neutral particles in the energy range 2E=0.4-1.4 GeV is mediated by the processes which need to be studied in more details. In particular, quark structure of the light scalar mesons can be studied in electric-dipole radiative decays ϕ → a 0 γ, f 0 γ; this physics can be studied with dedicated detector at higher statistics. For this purpose the SND was constructed with many improvements relative to ND. Experimental program of the SND is presented in Ref. and consists of items as follow. Radiative decays e + e − → ρ, ω, ϕ → π 0 γ, η γ ϕ → η ′ γ ϕ → a 0 γ, f 0 γ, π π γ, η π γ ρ, ω → π π γ OZI and G-parity suppressed decays ϕ → ω π 0, π π, η π π ρ → π + π − π 0 ω → π + π − Electromagnetic decays ρ, ω, ϕ → η e + e −, π 0 e + e − e+e− annihilation into hadrons e + e − → 2 π, 3 π, 4 π, 5 π e + e − → ω π, η π π, ϕ π e + e − → K + K −, K S 0 K L 0, K K π Test of QED processes e + e − → 3 γ, e + e − γ e + e − → 4 γ, e + e − γ γ, e + e − e + e − e + e − → 5 γ, 3 γ e + e −, 4 e γ Search for rare decays K S 0 → γ γ, 3 π 0, 2 π 0 γ, π 0 γ γ, π 0 e + e − {\displaystyle K_^\to \gamma \gamma,~~3\pi ^,~~2\pi ^\gamma,~~\pi ^\gamma \gamm


Istállós-kő is a mountain in Hungary. With a height of 958.1 metres above sea level it is the second highest mountain of the Bükk and the sixth highest of Hungary. Before 2014 it was considered to be the highest point of the area, but according to recent surveys Szilvási-kő is 960.715 metres meters tall. It is accessible from Szilvásvárad on a few hundred meters long tourist path, which leads to a cave in the mountain; the cave was first explored by Pál Roskó in 1911. It is a rich archaeological site with 30,000-40,000 year old finds including cave bear and Bison latifrons bones and tusks and bone tools and a Paleolithic hearth now displayed in the Hungarian National Museum; the site was excavated by Ottokár Kadić in 1929 and Mária Mottl in 1938. Based on fill stratification and animal remains used as period indicators, the archaeologists explored the cave's history, determined the age of the three cultural layers and the characteristics of the human population that lived there; the cave gained protected status in 1944 and specially protected status in 1982.

The newest excavations were led by Árpád Ringer. The importance of the cave lies in the findings of 66 different Ice Age species, which makes its fauna the richest among Aurignacian faunas in Europe. Vértes László: Az istállóskői barlang aurignaci II. Kultúrájának kormeghatározása, 1959, Akadémiai Nyomda, Budapest T. Dobosi Viola: Bone finds from Istállós-kő Cave, Praehistoria, 2002. 3. Évf. 79-102. Oldal Adams, Brian: New radiocarbon dates from Szeleta and Istállós-kő caves, Praehistoria, 2002. 3. Évf. 53-55. Oldal Ringer Árpád: The new image of Szeleta and Istállós-kő caves in the Bükk Mountains: a revision project between 1999-2002, Praehistoria, 2002. 3. Évf. 47-52. Oldal Az Istállós-kő és környezetének térképe Istállóskői ősemberbarlang Szilvásvárad