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| '''Neutral Detector''' ('''ND''') is a [[detector]] for [[particle physics]] [[experiment]]s created by the team of physicists in the
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| [[Budker Institute of Nuclear Physics]], [[Novosibirsk]], [[Russia]].
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| Experiments with the '''ND''' were conducted from 1982 to 1987 at the e<sup>+</sup>e<sup>−</sup> [[storage ring]] VEPP-2M in the [[energy]] range 2E=0.5-1.4 GeV.
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| == Physics ==
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| At the beginning of 80s the leading [[Scattering cross-section|cross sections]] of the [[electron]]-[[positron]] [[annihilation]] in the final states with [[charged particle]]s were measured in the energy range 2E=0.5-1.4 GeV. Processes with the [[neutral particle]]s in the final state were less studied. To investigate the [[Particle decay|radiative decays]] of the <math>\rho^0</math>, <math>\omega</math>, and <math>\phi</math> [[meson]]s and other processes involving [[photon]]s, <math>\pi^0</math>, and <math>\eta</math> [[meson]]s the '''ND'''
| | I'm a 36 years old, married and work at the high school (Educational Policy Studies).<br>In my free [http://Www.TimeIm.org/ time I'm] trying to teach myself Korean. I've been twicethere and look forward to returning sometime in the future. I like to read, preferably on my beloved Kindle. I like to watch How I Met Your Mother and Grey's Anatomy as well as documentaries about nature. I like Seashell Collecting.<br><br>my blog post [http://www.cheapdomains.com/review/networksolutions-com/ Cheap domains] |
| <ref name="ND">
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| {{cite journal
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| |last1=Golubev |first1=V. B.
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| |coauthors=''et al.''
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| |year=1984
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| |title=The neutral detector at VEPP-2M
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| |journal=Nuclear Instruments and Methods in Physics Research Section A
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| |volume=227 |number=3 |pages=467–469
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| |doi=10.1016/0168-9002(84)90202-X|bibcode = 1984NIMPA.227..467G }}</ref>
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| was constructed. Its distinguishing features are defined by the specially designed [[Calorimeter (particle physics)|electromagnetic calorimeter]] based on [[NaI]](Tl) [[scintillation counter]]s.
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| '''List of published analyses''' <ref name="Summary">
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| {{cite journal
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| |last1=Dolinsky |first1=S. I.
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| |coauthors=''et al.''
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| |year=1991
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| |title=Summary of experiments with the neutral detector at the e<sup>+</sup>e<sup>−</sup> storage ring VEPP-2M
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| |journal=Physics Reports
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| |volume=202 |number=3 |pages=99–170
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| |doi= 10.1016/0370-1573(91)90127-8|bibcode = 1991PhR...202...99D }}</ref>
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| * [[Particle decay|Radiative decays]]
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| : <math> e^+e^- \to \rho, \omega, \phi \to \pi^0 \gamma, \eta \gamma </math> <ref name="rad-dec-rho-omega">
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| {{cite journal
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| |last1=Dolinsky |first1=S. I.
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| |coauthors=''et al.''
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| |year=1984
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| |title=Radiative decays of ρ and ω mesons
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| |journal=[[Zeitschrift für Physik C]]
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| |volume=42 |number=4 |pages=511–518
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| |doi= 10.1007/BF01557655}}</ref><ref name="rad-dec-phi">
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| {{cite journal
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| |last1=Druzhinin |first1=V. P.
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| |coauthors=''et al.''
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| |year=1984
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| |title=Measurement of Φ-meson radiative decays at the storage ring VEPP-2M with the neutral detector
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| |journal=Physics Letters B
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| |volume=144 |number=1-2 |pages=136–140
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| |doi= 10.1016/0370-2693(84)90192-8 |bibcode = 1984PhLB..144..136D }}</ref>
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| : <math> \phi \to \eta^\prime \gamma </math> <ref name="search-rare-rad-dec-phi"> | |
| {{cite journal
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| |last1=Druzhinin |first1=V. P.
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| |coauthors=''et al.''
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| |year=1987
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| |title=Search for rare radiative decays of Φ-meson at VEPP-2M
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| |journal=[[Zeitschrift für Physik C]]
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| |volume=37 |number=1 |pages=1–5
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| |doi= 10.1007/BF01442062 |bibcode = 1987ZPhyC..37....1D }}</ref>
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| * Rare decays of the <math>\rho^0</math>, <math>\omega</math>, and <math>\phi</math> mesons
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| : <math> \omega, \phi \to \pi^0 e^+e^- </math> <ref>S.I. Dolinsky ''et al.'', Sov. J. Nucl. Phys. 48 (1988) 277.</ref>
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| : <math> \phi \to \pi^+ \pi^- </math> <ref>V. B. Golubev ''et al.'', Sov. J. Nucl. Phys. 44 (1986) 409.</ref>
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| * Search for rare decays
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| : <math> \rho \to \pi^+ \pi^- \pi^0 </math> <ref>V. B. Vasserman ''et al.'', Sov. J. Mod. Phys. 48 (1988) 480.</ref>
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| : <math> \omega, \phi \to \pi^0 \pi^0 \gamma </math> <ref name="rad-dec-rho-omega" /><ref name="search-rare-rad-dec-phi" />
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| : <math> \phi \to \pi^0 \eta \gamma </math> <ref>V. M. Aulchcnko ''et al.'', Preprini INP 87-90 (Novosibirsk, 1987).</ref>
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| : light scalars <math>a_0(980)</math> and <math>f_0(975)</math> in <math>\phi</math>-meson radiative decays <ref name="search-rare-rad-dec-phi" />
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| * Non-[[Resonance (particle physics)|resonant]] electron-positron [[annihilation]] into [[hadron]]s
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| : <math> e^+e^- \to \omega \pi^0 </math> <ref name="omega-pi0">
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| {{cite journal
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| |last1=Dolinsky |first1=S. I.
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| |coauthors=''et al.''
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| |year=1986
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| |title=The reaction e<sup>+</sup>e<sup>−</sup> → ωπ<sup>0</sup> in the cm energy range from 1.0 to 1.4 GeV
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| |journal=Phys. Lett. B
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| |volume=174 |number=4 |pages=453–457
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| |doi=10.1016/0370-2693(86)91036-1|bibcode = 1986PhLB..174..453D }}</ref>
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| : <math> e^+e^- \to \pi^+ \pi^- \pi^0 ,~~ \pi^+ \pi^- \eta </math> <ref>A. D. Bukin ''et al.'', Sov. J. Nucl. Phys. 50 (1989) 621.</ref><ref name="etapipi">
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| {{cite journal
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| |last1=Druzhinin |first1=V. P.
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| |coauthors=''et al.''
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| |year=1986
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| |title=Investigation of the reaction e<sup>+</sup>e<sup>−</sup> → ηπ<sup>+</sup>π<sup>−</sup> in the energy range up to 1.4 GeV
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| |journal=Phys. Lett. B
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| |volume=174 |number=1 |pages=115–117
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| |doi=10.1016/0370-2693(86)91140-8 |bibcode = 1986PhLB..174..115D }}</ref>
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| : <math> e^+e^- \to \pi^+ \pi^- \pi^+ \pi^-,~~ \pi^+ \pi^- \pi^0 \pi^0 </math> <ref>V. M. Aulchenko ''et al.'', Preprint INP 86-106 (Novosibirsk, 1987).</ref>
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| * Test of [[Quantum electrodynamics|QED]] processes <ref>V. P. Druzhinin ''et al.'', Preprint INP 85-98 (Novosibirsk, 1985).</ref><ref>V. M. Aulchcnko ''et al.'', Preprint INP 86-173 (Novosibirsk, 1986).</ref>
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| : <math> e^+e^- \to \gamma \gamma \gamma \gamma </math>
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| : <math> e^+e^- \to e^+e^- \gamma \gamma </math>
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| : <math> e^+e^- \to e^+e^- e^+e^- </math>
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| : <math> e^+e^- \to e^+e^- \gamma </math> (virtual Compton scattering) <ref>V. B. Golubev ''et al.'', Sov. J. Nucl. Phys. 41(1985) 752.</ref>
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| * Analyses of other processes
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| **Measurement of the ω-meson parameters <ref name="omega-pars">
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| {{cite journal
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| |last1=Aulchenko |first1=V. M.
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| |coauthors=''et al.''
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| |title=The width of the ω-meson
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| |journal=Phys. Lett. B
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| |volume=186 |number=3-4 |year=1987 |pages=432–434
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| |doi=10.1016/0370-2693(87)90322-4 |bibcode = 1987PhLB..186..432A }}</ref>
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| **Upper limits on electron [[Resonance (particle physics)|width]] of [[Scalar meson|scalar]] and [[tensor]] mesons <math>f_0(975)</math>, <math>f_2(1270)</math>, <math>f_0(1300)</math>, <math>a_0(980)</math>, and <math>a_2(1320)</math> <ref>P. V. Vorobyov ''et al.'', Sov. J. Nucl. Phys. 48 (1988) 436.</ref>
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| **<math> \phi \to \pi^+ \pi^- \pi^0,~~ K^0_S K^0_L </math> <ref>V. P. Druzhinin ''et al.'', Preprint INP 85-97 (Novosibirsk, 1985).</ref>
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| **Search for
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| ***<math> e^+e^- \to \pi^0 \pi^0 \gamma </math> <ref>V. B. Golubev ''et al.'', Sov. J. Nucl. Phys. 45 (1987) 622.</ref>
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| ***<math> K^0_S \to \gamma \gamma </math> <ref>I. B. Vasserman ''et al.'', JETP Lett. 43(1986) 588.</ref>
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| ***<math> e^+e^- \to C(1480) \to \phi \pi^0 </math> <ref>V. M. Aulchenko''et al.'', JETP Lett. 45 (1987) 145.</ref>
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| == Detector ==
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| :[[File:Neutral-Detector-R-Phi-projection-V2.gif|thumb|Neutral Detector r-φ view.]]
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| :[[File:Neutral-Detector-R-Theta-projection.gif|thumb|Neutral Detector r-θ view; 1-vacuum chamber of the storage ring, 2-cylindrical proportional chambers, 3-plastic scintillation counters, 4-NaI(Tl) counters, 5-flat proportional chambers, 6-iron absorber, 7-anticoincidence counters.]]
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| Based on goals of the physics program the '''ND''' consist of
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| '''Electromagnetic calorimeter'''
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| * 168 rectangular [[NaI]](Tl) scintillation counters
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| * total mass of [[NaI]](Tl) is 2.6 t
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| * solid angle coverage is 65% of 4π sr
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| * minimum thickness is 32 cm or 12 radiation length
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| * energy resolution for photons is σ/E = 4% / √E
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| '''Charged particle coordinate system'''
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| * 3 layers of coaxial cylindrical 2-d wire [[Wire chamber|proportional chambers]] in the center of the detector
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| * solid angle coverage is 80% of 4π sr
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| * angular resolution is 0.5° in the azimuthal and 1.5° in the polar direction
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| * surrounded by the 5-mm thick plastic scintillation counter for trigger
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| '''Flat (shower) coordinate 2-d wire proportional chambers''' | |
| * 2 layers of flat 2-d wire proportional chambers.
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| * angular resolution is 2° in the azimuthal and 3.5° in the polar direction for 0.5 GeV photons
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| '''Iron absorber & anti-coincidence counters'''
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| * The electromagnetic calorimeter is covered by the 10-cm thick iron absorber and plastic scintillation anti-coincidence counters.
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| == Results ==
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| [[Data]] collected with the '''ND''' experiment corresponds to the integrated [[luminosity]] 19 pb<sup>−1</sup>.
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| Results of the experiments with '''ND''' are presented in Ref.,<ref name="Summary" />
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| and are included in the [[Particle Data Group|PDG]] Review.
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| <ref>[http://pdg.lbl.gov/index.html The Review of Particle Physics], | |
| [http://iopscience.iop.org/0954-3899/37/7A/075021 K. Nakamura et al. (Particle Data Group), J. Phys. G 37, 075021 (2010)]</ref>
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| == References ==
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| {{reflist}}
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| == See also ==
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| * [[SND Experiment]]
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| * [[Particle detector]]
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| * [[Experimental physics]]
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| * [[List of accelerators in particle physics]]
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| * [[Budker Institute of Nuclear Physics]]
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| * [[Storage ring]]
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| * [[Meson]]
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| * [[List of particles]]
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| * [[Annihilation]]
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| == External links ==
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| * [http://www.inp.nsk.su/index.en.shtml Budker Institute of Nuclear Physics (BINP)]
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| * [http://www.inp.nsk.su/activity/old/vepp2m/index.ru.shtml VEPP-2M]
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| [[Category:Particle detectors]]
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| [[Category:Particle experiments]]
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| [[Category:Particle physics]]
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| [[Category:Experimental particle physics]]
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| [[Category:Particle physics facilities]]
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