arXiv subjects

P. Zh. Aslanyan

Publications and source records attributed to P. Zh. Aslanyan.

12 recordsLinked to original sources

arXiv2012

Preliminary study of the missing mass spectra via the $^{12}C(p, K^0_s)$ and $^{12}C(p,Λ)$ reactions at 10 GeV/c

The missing mass spectra for the $^{12}C(p, K^0_s)$ and $^{12}C(p,Λ)$ reactions have been studied by using of the propane bubble chamber(PBC) data from 700000 stereo photographs or $10^6$ inelastic interactions. The momentum spectrum of $π^-$ in range of 100-200 MeV/c have observed the significant enhancement from the p+C$\to π^-Λ$X(p+C$\toπ^-K^0_s$X) reaction. The missing mass spectra have been observed signals for the $p(p,π^-K^0_s)$, $^3H(p,pK^0_s)$, p(p,$Λ)π^-γ$ and p(p,$π^-)Λ$ reactions. This experimental study will need to continue by using of a different identification methods for a reaction channels.

hep-ex↗

arXiv2009

The Observed Correlations for the Strange Multibaryon States in Systems with $Λ$-Hyperon from pa Collision at Momentum of 10 Gev/$c$

he observed well-known resonances $Σ^0$ $Σ^{*+}$(1385) and $K^{*\pm}$(892) from PDG are good tests of this method. Exotic strange multibaryon states have been observed in the effective mass spectra of: $Λπ^{\pm}$,$Λγ$, $Λp$, $Λp p$ subsystems. The mean value of mass for $Σ^{*-}(1385)$ resonance is shifted till mass of 1370 MeV/$c^2$ and width is two times larger than the same value from PDG. Such kind of behavior for width and invariant mass of $Σ^{*-}(1385)$ resonance is interpreted as extensive contribution from stopped $Ξ^-\toΛπ^-$ and medium effect with invariant mass. The mean value of mass for $Σ^{*+}(1385)$ from secondary interactions is also shifted till mass of 1370 MeV/$c^2$. The width of $Σ^0$ is $\approx$ 2 times larger than the experimental error. There are enhancement production for all observed hyperons.

hep-ex↗

arXiv2008

Searches for Multibaryon States with $Λ$ Hyperon Systems in pa Collision at 10 Gev/c

Experimental data as a stereo photographs from the 2m propane bubble chamber LHE, JINR have been analyzed for exotic multibaryon metastable and stable states searches. A number of peculiarities were found in the effective mass spectra of: 1)$Λπ^{\pm}$,$Λπ^+ π^-$, $Λp$, $Λp p$, $Λπp$,$ΛΛ$ and $ΛK^0_S$ subsystems. The observed well known $Σ^{*+}$(1385),$Λ^*(1600)$ and $K^{*\pm}$(892)resonances are good tests for this method. The width of $Σ^{*-}(1385)$ for p+A reaction is two time larger than that presented in PDG. The $Λπ^-$ spectrum observed enhancement in mass range of 1345 MeV/$c^2$ which interpreted as a stopped in nucleus $Ξ^-$. The cross section of stopped $Ξ^-$ production is $\approx$ 8 times larger than obtained by fritiof model with same experimental conditions.

hep-ex↗

arXiv2007

Exotic strange multibaryon states searches with $Λ$- hyperon and $K^0_s$- meson systems in p+A collisions at momentum 10 GeV/c

Review for exotic strange multibaryon states were obseved in the effective mass spectra of: 1)$Λπ^+$, $Λπ^-$, $Λp$, $Λp p$, and $ΛK^0_S$, $K^0_Sπ^{\pm}$ and $K^0_Sp$ subsystems.The invariant mass of $Λπ^+$ and $K^0_Sπ^{\pm}$ spectra has observed well known $Σ^{*+}$(1385) and $K^{*\pm}$(892) resonances. The width of $Σ^{*-}(1385)$ for p+A reaction is two time larger than that presented in PDG. The cross section of $Ξ^-\to Λπ^-$ is 7-8 times larger than expected geometrical cross section in p+propane interaction. A few events detected on the photographs of the propane bubble chamber, were interpreted as S=-2 light and heavy $H^{0,+}$ dibaryons.

hep-ex↗

arXiv2007

Strange Multibaryon States with ΛHyperon Systems in pa Collision at 10 Gev/c

Experimental data from the 2m propane bubble chamber have been analyzed for exotic baryon states search. A number of peculiarities were found in the effective mass spectra of: $Λπ^+$($Σ^{*+}$(1382),PDG), $Λp$ and $Λp p$ subsystems. A few events detected on the photographs of the propane bubble chamber exposed to a 10 GeV/c proton beam, were interpreted as S=-2 $H^0$ light($<M_{(ΛΛ)}$) and heavy $H^{0,+}$. New event, detected on the photographs of the propane bubble chamber was interpreted as heavy $H^+(2488)$ dibaryon by weak decay channels of $K^-pp$ or $ Σ^+ pπ^-$.

hep-ex↗

arXiv2006

The Preliminary Result from ($K^0_sπ^{\pm}$) Spectra in p+a Reaction at 10 Gev/C

The experimental data from 2m propane bubble chamber have been analyzed to search of scalar meson $κ$(800) in $K^0_sπ^{\pm}$ spectra for the reaction p+A at 10 GeV/c. The $K^0_sπ^{\pm}$ invariant mass spectra has shown similarly resonant structures with $M_{K^0_sπ}$=720,780 and 890 MeV/$c^2$. The M(890) peak is identified as the well known resonance $K^*$ from PDG.

hep-ex↗

arXiv2006

The preliminary result from spectra of $K^0_s π^-$ in reaction p+propane at 10 GeV/c

The experimental data from 2m propane bubble chamber have been analyzed to search for scalar meson $κ(800)$ in a $K^0_sπ$ decay mode for the reaction p+$C_3H_8$ at 10 GeV/c. The $K^0_sπ^-$ invariant mass spectrum has shown resonant structures with $M_{K^0_sπ^-}$=730, 900 and $Γ$=143, 48 MeV/$c^2$, respectively. The statistical significance are estimated to be of 14.2$σ$ and 4.2$σ$, respectively. The peak in M(900) is identified as reflection from the well known resonance with mass of 892 MeV/c$^2$.

hep-ex↗

arXiv2005

Inclusive production of $Λ$, $K^0_s$ and exotic narrow resonances for systems $K_s^0 p$, $K_s^0 Λ$, $Λp$ from p+propane interactions at 10 GeV/c

Experimental data from the 2m propane bubble chamber for production of $Λ$, $K^0_s$ have been used to search of exotic baryon states, in the $K_s^0 p$, $K_s^0 Λ$ and $Λp$ decay mode for the reaction p+propane at 10 GeV/c. The estimation of experimental inclusive cross sections for $Λ$ and $K^0_s$ production in the p$^{12}C$ collision is equal to $σ_Λ$= 13.3$\pm$1.7 mb and $σ_{K^0_s}$= 3.8$\pm$0.6 mb, respectively. The measured $Λ/π^+$ ratio from pC reaction is equal to (5.3$\pm0.8)*10^{-2}$. The experimental $Λ/π^+$ ratio from the pC reaction is approximately two times larger than the $Λ/π^+$ ratio simulated by FRITIOF model from the pC reaction. The invariant mass spectrum $ΛK^0_s$ registered narrow peaks in regions of 1750 and 1795 MeV/$c^2$. The statistical significance of these peaks has been estimated as 5.6 and 3.3 S.D., respectively. These would be candidates for the $N^0$ or the $Ξ^0$ pentaquark states. The $pK^0_s$ invariant mass spectrum shows resonant structures with $M_{K_s^0 p}$=1540, 1613, 1821 MeV/$c^2$. The statistical significance of these peaks have been estimated as 5.5,4.8 and 5.0 s.d., respectively. The invariant mass spectrum S=-1 $Λp$ observed a narrow peaks at 2100, 2175,2285 and 2353 MeV/$c^2$. Their excess above background by the second method is 6.9, 4.9, 3.8 and 2.9 S.D., respectively.

hep-ex↗

arXiv2005

Exotic narrow resonance searches in the systems $K_s^0 p$, $K_s^0 Λ$ and $Λp$ in pA-interactions at 10 GeV/c

Experimental data from the 2m propane bubble chamber have been analyzed to search for an exotic baryon states, in the $K_s^0 p$, $K_s^0 Λ$ and $Λp$ decay mode for the reaction p+$C_3H_8$ at 10 GeV/c. The invariant mass spectrum $ΛK^0_s$ observe a narrow peaks at 1750, 1795,1850 MeV/$c^2$. The statistical significance of these peaks has been estimated as 5.6, 3.3 and 3.0 S.D., respectively. There are the small enhancements in mass regions of (1650-1675) and (1925-1950) MeV/c$^2$. These would be candidates for the $N^0$ or the $Ξ^0$ pentaquark states. The $pK^0_s$ invariant mass spectrum shows resonant structures with $M_{K_s^0 p}$=1540, 1613, 1821 MeV/$c^2$. The statistical significance of these peaks have been estimated as 5.5,4.8 and 5.0 s.d., respectively. There are also small peaks in 1487(3 s.d.),1690(3.6 s.d.), 1750(2.3 s.d.) and 1980(3.0 s.d.) MeV/$c^2$ mass regions. The invariant mass spectrum S=-1 $Λp$ observe a narrow peaks at 2100, 2175,2285 and 2353 MeV/$c^2$. Their excess above background by the second method is 6.9, 4.9, 3.8 and 2.9 S.D., respectively. There is also a small peak in 2225(2.2 s.d.) MeV/$c^2$ mass region.

hep-ex↗

arXiv2005

Exotic narrow resonance searches in the system Lambda K0s in p+propane collisions at 10 GeV/c

Experimental data from the 2m propane bubble chamber have been analyzed to search for an exotic baryon states, in the $ΛK^0_s$ decay mode for the reaction p+$C_3H_8$ at 10 GeV/c. The invariant mass spectrum $ΛK^0_s$ observe a narrow peaks at 1750$\pm$18, 1795$\pm$18,1850$\pm19$ MeV/$c^2$ and full widths of $Γ_{exp.}$= 32$\pm$6, 44$\pm$15, 29.0$\pm$8 MeV/$c^2$. The statistical significance of these peaks has been estimated as 5.6, 3.3 and 3.0 S.D., respectively. There are the small enhancements in mass regions of (1650-1675) and (1925-1950) МэВ/с$^2$. These would be candidates for the $N^0$ or the $Ξ^0$ pentaquark states. The investigation has been performed at the Veksler and Baldin Laboratory of High Energies, JINR.

hep-ex↗

arXiv2005

$Λ$ and $K^0_s$ Production in pC Collisions at 10 Gev/c

The experimental data from the 2m propane bubble chamber have been analyzed for pC$\to Λ(K^0_s)X$ reactions at 10 GeV/c. The estimation of experimental inclusive cross sections for $Λ$ and $K^0_s$ production in the p$^{12}C$ collision is equal to $σ_Λ$= 13.3$\pm$1.7 mb and $σ_{K^0_s}$= 3.8$\pm$0.6 mb, respectively. The measured $Λ/π^+$ ratio from pC reaction is equal to (5.3$\pm0.8)*10^{-2}$. The experimental $Λ/π^+$ ratio in the pC reaction is approximately two times larger than the $Λ/π^+$ ratio from pp reactions or from simulated pC reactions by FRITIOF model for the same energy. The $Λ/π^+$ ratio in interaction C+C at momentum 10 Gev/c is four times larger than the $Λ/π^+$ ratio from p+p reactions at the same energy.

hep-ex↗

arXiv2004

Observation of S=+1 narrow resonances in the system $K^0_sp$ from p+$C_3H_8$ collision at 10 GeV/c

The 2m propane bubble chamber experimental data have been analyzed to search for an exotic baryon state, the $Θ^+$ -baryon, in the $pK^0_s$ decay mode for the reaction p+$C_3H_8$ at 10 GeV/c. The $pK^0_s$ invariant mass spectrum shows resonant structures with $M_{K_s^0 p}$=1540$\pm$8, 1613$\pm$10, 1821$\pm$11 MeV/$c^2$ and $Γ_{K_s^0 p}$= 9.2$\pm$1.8, 16.1$\pm$4.1, 28.0$\pm$9.4 MeV/$c^2$. The maximal statistical significance of these peaks have been estimated as 5.5$σ$,4.8$σ$ and 5.0$σ$, respectively.

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