We study the $\Lambda(1405)$ resonance with $I(J^{P})=0(1/2^{-}) $ in the context of the pentaquark hypothesis in the nuclear medium. To explore the influence of the nuclear medium on the physical parameters of $\Lambda(1405)$, we propose a molecular-type structure involving admixtures of $K^{-}p$ and $\bar{K}^{0}n$, correlated with the nuclear matter density. Our analysis reveals a substantial shift in mass and residue, approximately $20\%$ and $38\%$, respectively. These findings have significant implications for experimental researchers aiming to identify in-medium characteristics of hyperon resonances.

Abstract The spectroscopic parameters as well as electromagnetic form factor of the strange particle kaon are investigated in vacuum and a medium with finite density. The obtained vacuum mass and decay constant, which are consistent with the existing experimental results, are used to extract the $$ Q^2 $$ Q 2 dependence of the kaon electromagnetic form factor in the interval $$Q^2\in [0,10]$$ Q 2 ∈ [ 0 , 10 ] GeV $$^2$$ 2 in vacuum. The obtained results at lower and intermediate values of $$ Q^2 $$ Q 2 are consistent with the existing experimental data within the presented uncertainties. The $$ Q^2 $$ Q 2 behavior of the electromagnetic form factor of kaon in vacuum and in the interval $$Q^2\in [0,6]$$ Q 2 ∈ [ 0 , 6 ] GeV $$^2$$ 2 is in a nice agreement with the existing predictions of the Lattice QCD and the solution of the Bethe–Salpeter equation for the model of Nambu and Jona-Lasinio (NJL) with proper-time regularization, as well. The obtained vacuum radius for kaon is also in a nice agreement with the world’s average experimental result. We extend the analyses to a medium with higher densities and obtain the behavior of the mass, decay constant, electromagnetic form factor and radius with respect to density. The obtained results for some of the parameters are compared with the existing predictions of other models and approaches. The results obtained in the present study can be useful for future experimental and theoretical studies both in vacuum and a dense medium.

The Crystal Barrel is an electromagnetic calorimeter consisting of 1380 CsI(Tl) scintillators, and is currently installed at the CBELSA/TAPS experiment where it is used to detect decay products from photoproduction of mesons. The readout of the Crystal Barrel has been upgraded in order to integrate the detector into the first level of the trigger and to increase its sensitivity for neutral final states. The new readout uses avalanche photodiodes in the front-end and a dual back-end with branches optimized for energy and time measurement, respectively. An FPGA-based cluster finder processes the whole hit pattern within less than 100 ns. The important downside of APDs -- the temperature dependence of their gain -- is handled with a temperature stabilization and a compensating bias voltage supply. Additionally, a light pulser system allows the APDs' gains to be measured during beamtimes.

PANDA (anti-Proton ANnihiliation at DArmstadt) is planned to be one of the four main experiments at the future international accelerator complex FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. It is going to address fundamental questions of hadron physics and quantum chromodynamics using cooled antiproton beams with a high intensity and and momenta between 1.5 and 15 GeV/c. PANDA is designed to reach a maximum luminosity of 2x10^32 cm^2 s. Most of the physics programs require an excellent particle identification (PID). The PID of hadronic states at the forward endcap of the target spectrometer will be done by a fast and compact Cherenkov detector that uses the detection of internally reflected Cherenkov light (DIRC) principle. It is designed to cover the polar angle range from 5{\deg} to 22{\deg} and to provide a separation power for the separation of charged pions and kaons up to 3 standard deviations (s.d.) for particle momenta up to 4 GeV/c in order to cover the important particle phase space. This document describes the technical design and the expected performance of the novel PANDA Disc DIRC detector that has not been used in any other high energy physics experiment (HEP) before. The performance has been studied with Monte-Carlo simulations and various beam tests at DESY and CERN. The final design meets all PANDA requirements and guarantees suffcient safety margins.

Abstract We report on some properties of the newly observed charged hidden-charmed open strange $$ Z_{cs}(3985)^- $$ Z cs ( 3985 ) - state by BESIII Collaboration. Assigning the quantum numbers $$ J^{P} = 1^{+}$$ J P = 1 + and the quark composition $$ c \bar{c} s\bar{u} $$ c c ¯ s u ¯ and considering it as the strange partner of the famous $$ Z_c(3900) $$ Z c ( 3900 ) state, we estimate the mass of the $$ Z_{cs}(3985)^- $$ Z cs ( 3985 ) - resonance in vacuum and compare it with the experimental data. We also investigate its mass, current coupling and vector-self energy in a medium with finite density. Our result on the mass in vacuum agrees well with the experimental data. We estimate the mass and current coupling of the b-partner of this state, $$ Z_{bs}$$ Z bs , in the vacuum as well. For its mass we get $$ m_{Z_{bs}}= 10732^{+97}_{-46}~\hbox {MeV}$$ m Z bs = 10732 - 46 + 97 MeV , which may be checked via other nonperturbative approaches as well as future experiments. We present the dependence of the spectroscopic parameters of $$ Z_{cs}(3985)^- $$ Z cs ( 3985 ) - state on density and observe that these parameters are linearly changed with increasing in the density.

For the fusion reactor ITER, a mandatory monitor of the fusion device and plasma will be performed with optical diagnostic systems. For the metallic first mirrors, the recovery of the reflectivity losses due to dust deposition is proposed to be carried out for 14 different optical diagnostic systems by the plasma cleaning technique. In this work, we studied the influence of the electrode area on the electrode potential as a function of the applied power with a 60 MHz radio very high frequency source. Unshielded copper disks with different diameters were constructed to study the impact of the electrode area in the range of 90 cm(2) to 1200 cm(2), which corresponds to an Edge Thomson Scattering area ratio of 0.15 to 2. It was observed that the absolute value of the resulting bias decreased from 280 V to 15 V with the increase of the area for a given RF power. Moreover, the power consumption was reduced by 43 % using a pre-matching element close to the vacuum feedthrough. The cleaning homogeneity on a curved and a large size mirror was studied, and the difference between the center and edge maximum/minimum was around 20 % and 40 % for the curved and large size mirror, respectively. For ITER, it is required to have an End-of-Cleaning Indicator (ECI), which shows when the cleaning process would be stopped. In this work, we studied the feasibility of Optical Emission Spectroscopy (OES) as a real-time control tool for the RF cleaning process. With 13.56 or 60 MHz, it was possible to use OES as ECI by following the molybdenum (Mo), rhodium (Rh), and aluminum (Al) emission lines. The decrease of Al I line and increase of the Mo I and Rh I line were recorded as a function of the cleaning time.

AbstractThe antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: $${\bar{p}}p \rightarrow {\bar{\varLambda }}\varLambda $$ p ¯ p → Λ ¯ Λ and $${\bar{p}}p \rightarrow {\bar{\varXi }}^+\varXi ^-$$ p ¯ p → Ξ ¯ + Ξ - . The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.

We report on some properties of the newly observed charged hidden-charmed open strange $$ Z_{cs}(3985)^- $$ Z cs ( 3985 ) - state by BESIII Collaboration. Assigning the quantum numbers $$ J^{P} = 1^{+}$$ J P = 1 + and the quark composition $$ c \bar{c} s\bar{u} $$ c c ¯ s u ¯ and considering it as the strange partner of the famous $$ Z_c(3900) $$ Z c ( 3900 ) state, we estimate the mass of the $$ Z_{cs}(3985)^- $$ Z cs ( 3985 ) - resonance in vacuum and compare it with the experimental data. We also investigate its mass, current coupling and vector-self energy in a medium with finite density. Our result on the mass in vacuum agrees well with the experimental data. We estimate the mass and current coupling of the b-partner of this state, $$ Z_{bs}$$ Z bs , in the vacuum as well. For its mass we get $$ m_{Z_{bs}}= 10732^{+97}_{-46}~\hbox {MeV}$$ m Z bs = 10732 - 46 + 97 MeV , which may be checked via other nonperturbative approaches as well as future experiments. We present the dependence of the spectroscopic parameters of $$ Z_{cs}(3985)^- $$ Z cs ( 3985 ) - state on density and observe that these parameters are linearly changed with increasing in the density.

The study of baryon excitation spectra provides insight into the inner structure of baryons. So far, most of the world-wide efforts have been directed towards N^* and spectroscopy. Nevertheless, the study of the double and triple strange baryon spectrum provides independent information to the N^* and spectra. The future antiproton experiment P ANDA will provide direct access to final states containing a pair, for which production cross sections up to μ b are expected in p̅ p reactions. With a luminosity of L=10^31 cm ^-2 s ^-1 in the first phase of the experiment, the expected cross sections correspond to a production rate of ∼ 10^6 events /day . With a nearly 4π detector acceptance, P ANDA will thus be a hyperon factory. In this study, reactions of the type p̅ p → ^+ ^*- as well as p̅ p → ^*+ ^- with various decay modes are investigated. For the exclusive reconstruction of the signal events a full decay tree fit is used, resulting in reconstruction efficiencies between 3 and 5

The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: $${\bar{p}}p \rightarrow {\bar{\varLambda }}\varLambda $$ p ¯ p → Λ ¯ Λ and $${\bar{p}}p \rightarrow {\bar{\varXi }}^+\varXi ^-$$ p ¯ p → Ξ ¯ + Ξ - . The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.

The Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, provides unique possibilities for a new generation of hadron-, nuclear- and atomic physics experiments. The future antiProton ANnihilations at DArmstadt (PANDA or PANDA) experiment at FAIR will offer a broad physics programme, covering different aspects of the strong interaction. Understanding the latter in the non-perturbative regime remains one of the greatest challenges in contemporary physics. The antiproton-nucleon interaction studied with PANDA provides crucial tests in this area. Furthermore, the high-intensity, low-energy domain of PANDA allows for searches for physics beyond the Standard Model, e.g. through high precision symmetry tests. This paper takes into account a staged approach for the detector setup and for the delivered luminosity from the accelerator. The available detector setup at the time of the delivery of the first antiproton beams in the HESR storage ring is referred to as the Phase One setup. The physics programme that is achievable during Phase One is outlined in this paper.

The study of baryon excitation spectra provides insight into the inner structure of baryons. So far, most of the world-wide efforts have been directed towards $$N^*$$ and $$\varDelta $$ spectroscopy. Nevertheless, the study of the double and triple strange baryon spectrum provides independent information to the $$N^*$$ and $$\varDelta $$ spectra. The future antiproton experiment $$\overline{\text{ P }}$$ ANDA will provide direct access to final states containing a $${\overline{\varXi }}\varXi $$ pair, for which production cross sections up to $$\mu \text{ b }$$ are expected in $$\bar{\text{ p }}$$ p reactions. With a luminosity of $$L=10^{31}$$ cm $$^{-2}$$ s $$^{-1}$$ in the first phase of the experiment, the expected cross sections correspond to a production rate of $$\sim 10^6\, \text{ events }/\text{day }$$ . With a nearly $$4\pi $$ detector acceptance, $$\overline{\text{ P }}$$ ANDA will thus be a hyperon factory. In this study, reactions of the type $$\bar{\text{ p }}$$ p $$\rightarrow $$ $${\overline{\varXi }}^{+}$$ $$\varXi ^{*-}$$ as well as $$\bar{\text{ p }}$$ p $$\rightarrow $$ $${\overline{\varXi }}^{*+}$$ $$\varXi ^{-}$$ with various decay modes are investigated. For the exclusive reconstruction of the signal events a full decay tree fit is used, resulting in reconstruction efficiencies between 3 and 5%. This allows high statistics data to be collected within a few weeks of data taking.

The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: $${\bar{p}}p \rightarrow {\bar{\varLambda }}\varLambda $$ and $${\bar{p}}p \rightarrow {\bar{\varXi }}^+\varXi ^-$$ . The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.

This paper reports on Monte Carlo simulation results for future measurements of the moduli of time-like proton electromagnetic form factors, $$|G_{E}|$$ | G E | and $$|G_{M}|$$ | G M | , using the $$\bar{p} p \rightarrow \mu ^{+} \mu ^{-}$$ p ¯ p → μ + μ - reaction at $$\overline{\text {P}}\text {ANDA}$$ P ¯ ANDA (FAIR). The electromagnetic form factors are fundamental quantities parameterizing the electric and magnetic structure of hadrons. This work estimates the statistical and total accuracy with which the form factors can be measured at $$\overline{\text {P}}\text {ANDA}$$ P ¯ ANDA , using an analysis of simulated data within the PandaRoot software framework. The most crucial background channel is $$\bar{p} p \rightarrow \pi ^{+} \pi ^{-}$$ p ¯ p → π + π - , due to the very similar behavior of muons and pions in the detector. The suppression factors are evaluated for this and all other relevant background channels at different values of antiproton beam momentum. The signal/background separation is based on a multivariate analysis, using the Boosted Decision Trees method. An expected background subtraction is included in this study, based on realistic angular distributions of the background contribution. Systematic uncertainties are considered and the relative total uncertainties of the form factor measurements are presented.

The study of baryon excitation spectra provides insight into the inner structure of baryons. So far, most of the world-wide efforts have been directed towards N ∗ and Δ spectroscopy. Nevertheless, the study of the double and triple strange baryon spectrum provides independent information to the N ∗ and Δ spectra. The future antiproton experiment PANDA will provide direct access to final states containing a ΞΞ pair, for which production cross sections up to μ b are expected in ¯ pp reactions. With a luminosity of L = 10 31 cm − 2 s − 1 in the first phase of the experiment, the expected cross sections correspond to a production rate of ∼ 10 6 events / day. With a nearly 4 π detector acceptance, PANDA will thus be a hyperon factory. In this study, reactions of the type ¯ pp → Ξ + Ξ ∗− as well as ¯ pp → Ξ ∗+ Ξ − with various decay modes are investigated. For the exclusive reconstruction of the signal events a full decay tree fit is used, resulting in reconstruction efficiencies between 3 and 5%. This allows high statistics data to be collected within a few weeks of data taking.

This paper reports on Monte Carlo simulation results for future measurements of the moduli of time-like proton electromagnetic form factors, vertical bar G(E)vertical bar and vertical bar G(M)vertical bar, using the (p) over barp -> mu(+)mu(-) reaction at PANDA (FAIR). The electromagnetic form factors are fundamental quantities parameterizing the electric and magnetic structure of hadrons. This work estimates the statistical and total accuracy with which the form factors can be measured at PANDA, using an analysis of simulated data within the PandaRoot software framework. The most crucial background channel is (p) over barp -> pi(+)pi(-), due to the very similar behavior of muons and pions in the detector. The suppression factors are evaluated for this and all other relevant background channels at different values of antiproton beam momentum. The signal/background separation is based on a multivariate analysis, using the Boosted Decision Trees method. An expected background subtraction is included in this study, based on realistic angular distributions of the background contribution. Systematic uncertainties are considered and the relative total uncertainties of the form factor measurements are presented.

The Muon Scattering Experiment at the Paul Scherrer Institute uses a mixed beam of electrons, muons, and pions, necessitating precise timing to identify the beam particles and reactions they cause. We describe the design and performance of three timing detectors using plastic scintillator read out with silicon photomultipliers that have been built for the experiment. The Beam Hodoscope, upstream of the scattering target, counts the beam flux and precisely times beam particles both to identify species and provide a starting time for time-of-flight measurements. The Beam Monitor, downstream of the scattering target, counts the unscattered beam flux, helps identify background in scattering events, and precisely times beam particles for time-of-flight measurements. The Beam Focus Monitor, mounted on the target ladder under the liquid hydrogen target inside the target vacuum chamber, is used in dedicated runs to sample the beam spot at three points near the target center, where the beam should be focused.

This study sought to determine the rate of sinus membrane perforation in patients undergoing crestal sinus grafting, as well as the effect of Schneiderian membrane thickness and residual bone height (RBH) on membrane perforation, using cone beam computed tomography. The study included 25 patients undergoing 44 crestal sinus grafting procedures. The sites for crestal sinus grafting were divided into a control group (RBH≥5mm) and a test group (RBH<5mm). All sinus grafting procedures were also categorised based on membrane thickness: group A (<1mm), group B (1–2mm), and group C (≥2mm). The rate of membrane perforation was 18.2%. The median RBH measurement was 5.59mm. No statistically significant difference in membrane perforation rate was found between the test and control groups (P=0.262). The median thickness of the Schneiderian membrane was 1.35mm. There was no statistically significant difference in membrane perforation among the three membrane thickness groups (P=0.431). No significant correlation between RBH and membrane perforation was observed, although clinical observation indicated that there was a tendency for an increased membrane perforation rate in the presence of a RBH<5mm. The perforation rate was found to be at its highest when the membrane was thinner than 1mm.

The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels. The results, presented in detail in this paper, show that octet hyperon-antihyperon pairs can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA. PACS. 13.30.-a Baryon decay – 13.60.Rj Baryon production – 13.75.-n Hadron-induced lowand intermediate energy reactions and scattering – 13.88.+e Polarization in interactions and scattering – 14.20.Jn Hyperons