Pub Date : 2024-08-14DOI: 10.1134/s1547477124700821
A. D. Dolgov, A. S. Rudenko
Abstract
The conversion of protons to positrons at the horizon of a black hole (BH) is considered. It is shown that the process may efficiently proceed for BHs with masses in the range ( sim {{10}^{{18}}})–({{10}^{{21}}}) g. It is argued that the electric charge of BH acquired by the proton accretion to BH could create electric field near BH horizon close to the critical Schwinger one. It leads to efficient electron-positron pair production, when electrons are back captured by the BH while positrons are emitted into outer space. Annihilation of these positrons with electrons in the interstellar medium may at least partially explain the origin of the observed 511 keV line.
{"title":"Conversion of Protons to Positrons by a Black Hole","authors":"A. D. Dolgov, A. S. Rudenko","doi":"10.1134/s1547477124700821","DOIUrl":"https://doi.org/10.1134/s1547477124700821","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The conversion of protons to positrons at the horizon of a black hole (BH) is considered. It is shown that the process may efficiently proceed for BHs with masses in the range <span>( sim {{10}^{{18}}})</span>–<span>({{10}^{{21}}})</span> g. It is argued that the electric charge of BH acquired by the proton accretion to BH could create electric field near BH horizon close to the critical Schwinger one. It leads to efficient electron-positron pair production, when electrons are back captured by the BH while positrons are emitted into outer space. Annihilation of these positrons with electrons in the interstellar medium may at least partially explain the origin of the observed 511 keV line.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s1547477124700869
Chetna, Md. M. Shaikh, P. Singh, R. Kharab
Abstract
The influence on elastic scattering angular distribution (ESAD) and total fusion (TF) excitation function of couplings to breakup channel has been investigated for 9Be + 209Bi system at near and above barrier energies. The three body continuum discretized coupled channel (CDCC) calculations, (two body (8Be + n) projectile and target), are performed by making use of the code FRESCO. The ESADs are found to be in good accord with experimental observations. However, an enhancement is observed in the CDCC predictions of total fusion excitation function with respect to the data when breakup couplings are taken into account.
{"title":"Investigation of the Projectile Breakup Effects on Elastic Scattering and Fusion for 9Be + 209Bi System at Around Barrier Energies","authors":"Chetna, Md. M. Shaikh, P. Singh, R. Kharab","doi":"10.1134/s1547477124700869","DOIUrl":"https://doi.org/10.1134/s1547477124700869","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The influence on elastic scattering angular distribution (ESAD) and total fusion (TF) excitation function of couplings to breakup channel has been investigated for <sup>9</sup>Be + <sup>209</sup>Bi system at near and above barrier energies. The three body continuum discretized coupled channel (CDCC) calculations, (two body (<sup>8</sup>Be + <i>n</i>) projectile and target), are performed by making use of the code FRESCO. The ESADs are found to be in good accord with experimental observations. However, an enhancement is observed in the CDCC predictions of total fusion excitation function with respect to the data when breakup couplings are taken into account.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s1547477124701255
E. A. Butenko, D. E. Donets, M. G. Dzugaev, N. A. Malyshev, E. S. Matyuhkanov, D. O. Ponkin, D. N. Rassadov
Abstract
The Electron String Ion Source (ESIS) is type of electron beam ion source working in a reflex mode under specific conditions [1]. The operation is based on step-by-step ionization of the ions by hitting with electrons of an electron string. ESIS is a complex facility and ion trap control system is its important part. It affects ion beam formation process and transfer to NICA HILAC. The version, which is under operation now is based on resistance divider. The new system is based on independent modules and could make operation process more flexible. The paper describes development of the ESIS ion trap control system electronics, its modifications and operation process.
摘要电子串离子源（ESIS）是一种在特定条件下以反射模式工作的电子束离子源[1]。其工作原理是通过电子串的电子撞击离子，使离子逐步电离。ESIS 是一个复杂的设备，离子阱控制系统是其重要组成部分。它影响着离子束的形成过程和向 NICA HILAC 的传输。目前正在运行的版本是基于电阻分压器的。新系统以独立模块为基础，可以使操作过程更加灵活。本文介绍了 ESIS 离子阱控制系统电子系统的开发、改进和运行过程。
{"title":"Electron String Ion Source (ESIS) Ion Trap Control System Development","authors":"E. A. Butenko, D. E. Donets, M. G. Dzugaev, N. A. Malyshev, E. S. Matyuhkanov, D. O. Ponkin, D. N. Rassadov","doi":"10.1134/s1547477124701255","DOIUrl":"https://doi.org/10.1134/s1547477124701255","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The Electron String Ion Source (ESIS) is type of electron beam ion source working in a reflex mode under specific conditions [1]. The operation is based on step-by-step ionization of the ions by hitting with electrons of an electron string. ESIS is a complex facility and ion trap control system is its important part. It affects ion beam formation process and transfer to NICA HILAC. The version, which is under operation now is based on resistance divider. The new system is based on independent modules and could make operation process more flexible. The paper describes development of the ESIS ion trap control system electronics, its modifications and operation process.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s1547477124700730
K. Logacheva, P. Gergelezhiu, E. Raksha, L. Savostina, G. Arzumanyan, A. Eresko, S. Malakhov, K. Mamatkulov, O. Ponomareva, A. Belushkin, D. Chudoba
Abstract
Vibrational spectroscopic features of ibuprofen and ketoprofen (non-steroidal anti-inflammatory drugs) were determined as a result of joint analysis of experimental and DFT-calculated data. There is a good agreement between the experimental (IR, Raman) and calculated (BP86/def2-SVP) vibrational frequencies of ibuprofen and ketoprofen.
{"title":"Vibrational Spectroscopic Features of Ibuprofen and Ketoprofen: IR and Raman Spectroscopy Combined with DFT Calculations","authors":"K. Logacheva, P. Gergelezhiu, E. Raksha, L. Savostina, G. Arzumanyan, A. Eresko, S. Malakhov, K. Mamatkulov, O. Ponomareva, A. Belushkin, D. Chudoba","doi":"10.1134/s1547477124700730","DOIUrl":"https://doi.org/10.1134/s1547477124700730","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Vibrational spectroscopic features of ibuprofen and ketoprofen (non-steroidal anti-inflammatory drugs) were determined as a result of joint analysis of experimental and DFT-calculated data. There is a good agreement between the experimental (IR, Raman) and calculated (BP86/def2-SVP) vibrational frequencies of ibuprofen and ketoprofen.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s154747712470122x
I. A. Yujakov, A. I. Madzhidov, V. V. Dmitrenko, S. E. Ulin, K. F. Vlasik, V. M. Grachev, R. R. Egorov, K. V. Krivova, Z. M. Uteshev, I. V. Chernysheva, A. E. Shustov
Abstract
The results of testing a xenon gamma spectrometer based on the use of an ionization chamber with compressed xenon are presented. A standard source ({}_{{27}}^{{60}}text{Co}) was used to study the characteristics of the spectrometer. The main characteristics were measured: registration efficiency of 2%, energy resolution of 1.4%.
{"title":"Investigation of the Capabilities of a Xenon Gamma-Ray Spectrometer to Assess the Activity of an Isotope 60Co","authors":"I. A. Yujakov, A. I. Madzhidov, V. V. Dmitrenko, S. E. Ulin, K. F. Vlasik, V. M. Grachev, R. R. Egorov, K. V. Krivova, Z. M. Uteshev, I. V. Chernysheva, A. E. Shustov","doi":"10.1134/s154747712470122x","DOIUrl":"https://doi.org/10.1134/s154747712470122x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The results of testing a xenon gamma spectrometer based on the use of an ionization chamber with compressed xenon are presented. A standard source <span>({}_{{27}}^{{60}}text{Co})</span> was used to study the characteristics of the spectrometer. The main characteristics were measured: registration efficiency of 2%, energy resolution of 1.4%.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s1547477124701097
T. R. Yakubov, G. N. Timoshenko, L. G. Beskrovnaya, V. N. Shvetsov
Abstract
Results of the measurements of neutron spectra at two points at the intense resonance neutron source (IREN) of the JINR’s Laboratory of Neutron Physics are presented. Powerful neutron fluxes are obtained using an electron accelerator and the thick tungsten target, in which neutrons are produced by bremsstrahlung gamma-quanta of electrons hitting the target. The tungsten target is placed in a cylindrical vessel filled with water. Neutron spectra were obtained using a multisphere Bonner spectrometer at two points behind biological shielding. Based on the spectra obtained, the effective neutron dose rates at the measurement points were determined, which is of importance both for assessing the radiation situation at IREN and for comparison with the readings of neutron dosimeters of the automated radiation monitoring system.
{"title":"Measurements of the Spectral and Dose Characteristics of the Neutron Field Behind the Biological Shielding of the IREN Source for 60-MeV Electrons","authors":"T. R. Yakubov, G. N. Timoshenko, L. G. Beskrovnaya, V. N. Shvetsov","doi":"10.1134/s1547477124701097","DOIUrl":"https://doi.org/10.1134/s1547477124701097","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Results of the measurements of neutron spectra at two points at the intense resonance neutron source (IREN) of the JINR’s Laboratory of Neutron Physics are presented. Powerful neutron fluxes are obtained using an electron accelerator and the thick tungsten target, in which neutrons are produced by bremsstrahlung gamma-quanta of electrons hitting the target. The tungsten target is placed in a cylindrical vessel filled with water. Neutron spectra were obtained using a multisphere Bonner spectrometer at two points behind biological shielding. Based on the spectra obtained, the effective neutron dose rates at the measurement points were determined, which is of importance both for assessing the radiation situation at IREN and for comparison with the readings of neutron dosimeters of the automated radiation monitoring system.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s1547477124700791
N. Jain, M. Bhuyan, R. Kumar
Abstract
The (alpha )-decay half-lives of superheavy nuclei with (100 leqslant Z leqslant 120) are comprehensively analyzed using the axially deformed relativistic mean field (RMF) formalism for the NL3* parameter set. We employ RMF binding energies to determine the (alpha )-decay energies and make a comparison with both the available experimental data and the theoretical results obtained from the global nuclear mass model WS4. The four distinct formulae, specifically the modified scaling law Brown, modified Viola-Seaborg, Yibin et al. formula, and its modified form are used to calculate the decay half-lives and examine the numerical correlation between the half-life (({{T}_{{1/2}}})) for each (alpha )-decay energy. We notice that ({{T}_{{1/2}}}) is significantly dependent on the decay formula in terms of isospin asymmetry and decay energy. We also noticed that modified scaling law Brown formula estimates of half-lives agreed comparatively better with the experiment as compared to others. Moreover, the present investigation provides significant information on the stability of the superheavy island considered for ongoing and/or future experiments.
{"title":"Relativistic Mean-Field Study of Alpha Decay in Superheavy Isotopes with 100 ≤ Z ≤ 120","authors":"N. Jain, M. Bhuyan, R. Kumar","doi":"10.1134/s1547477124700791","DOIUrl":"https://doi.org/10.1134/s1547477124700791","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The <span>(alpha )</span>-decay half-lives of superheavy nuclei with <span>(100 leqslant Z leqslant 120)</span> are comprehensively analyzed using the axially deformed relativistic mean field (RMF) formalism for the NL3* parameter set. We employ RMF binding energies to determine the <span>(alpha )</span>-decay energies and make a comparison with both the available experimental data and the theoretical results obtained from the global nuclear mass model WS4. The four distinct formulae, specifically the modified scaling law Brown, modified Viola-Seaborg, Yibin et al. formula, and its modified form are used to calculate the decay half-lives and examine the numerical correlation between the half-life (<span>({{T}_{{1/2}}})</span>) for each <span>(alpha )</span>-decay energy. We notice that <span>({{T}_{{1/2}}})</span> is significantly dependent on the decay formula in terms of isospin asymmetry and decay energy. We also noticed that modified scaling law Brown formula estimates of half-lives agreed comparatively better with the experiment as compared to others. Moreover, the present investigation provides significant information on the stability of the superheavy island considered for ongoing and/or future experiments.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s1547477124701395
M. Dima, M.-T. Dima, M. Mihailescu
Abstract
Circle fit routines are used in helix reconstruction for tracking and in ring reconstruction for particle ID. While accurate fits can be achieved with iterative fits, often resolution can be relaxed in favor of speed. We present and compare two flash-algorithms in terms of resolution, CPU speed and mathematical advantage (linearity). The second algorithm is novel.
{"title":"Flash-Fit Algorithms for Circles in Particle Physics","authors":"M. Dima, M.-T. Dima, M. Mihailescu","doi":"10.1134/s1547477124701395","DOIUrl":"https://doi.org/10.1134/s1547477124701395","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Circle fit routines are used in helix reconstruction for tracking and in ring reconstruction for particle ID. While accurate fits can be achieved with iterative fits, often resolution can be relaxed in favor of speed. We present and compare two flash-algorithms in terms of resolution, CPU speed and mathematical advantage (linearity). The second algorithm is novel.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s1547477124701474
A. Khelashvili, T. Nadareishvili
Abstract
We study the behavior of reduced radial wave function at the origin for multidimensional Schrodinger equation, where the angular variables are separated by using a hyperspherical formalism and the overall potential is chosen symmetric under rotations in full Euclidean space. It is shown that the rigorous restriction at the origin—Dirichlet boundary condition follows only in three-dimensional space, whereas in other dimensions (more than three) some physical reasonings are necessary in addition. According to our previous investigation the most appropriate is the Hermiticity of Hamiltonian or, equivalently, the conservation of particle number. In this case the preferable is a Dirichlet condition again for regular potentials, but for singular potentials (not soft) other conditions are also allowed together with it. In this meaning the three dimensions is a peculiar one.
{"title":"The Boundary Condition for Reduced Radial Wave Function in Multi-Dimensional Schrodinger Equation","authors":"A. Khelashvili, T. Nadareishvili","doi":"10.1134/s1547477124701474","DOIUrl":"https://doi.org/10.1134/s1547477124701474","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>We study the behavior of reduced radial wave function at the origin for multidimensional Schrodinger equation, where the angular variables are separated by using a hyperspherical formalism and the overall potential is chosen symmetric under rotations in full Euclidean space. It is shown that the rigorous restriction at the origin—Dirichlet boundary condition follows only in three-dimensional space, whereas in other dimensions (more than three) some physical reasonings are necessary in addition. According to our previous investigation the most appropriate is the Hermiticity of Hamiltonian or, equivalently, the conservation of particle number. In this case the preferable is a Dirichlet condition again for regular potentials, but for singular potentials (not soft) other conditions are also allowed together with it. In this meaning the three dimensions is a peculiar one.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-14DOI: 10.1134/s1547477124701243
O. Brovko, E. Syresin, V. Morozova, D. Morozov, A. Karpuk, M. Yablochkin, A. Malyshev
Abstract
The work is devoted to the creation of an automatic frequency control system for the harmonic station RF3 of the NICA collider. The special attention was paid to the main tasks and the algorithm of the station’s work. Based on the studied modes of station’s operation, a program for generating control pulses was developed. They are used for moving the tuners which set up the station to the resonant frequency. The created program was loaded into the prototype of the control unit and debugged in the computer program, after that it was integrated into the general project.
摘要 这项工作致力于为 NICA 对撞机的 RF3 谐波站创建一个自动频率控制系统。该系统特别关注谐波站工作的主要任务和算法。根据所研究的台站运行模式，开发了一个用于生成控制脉冲的程序。这些脉冲用于将调谐器移动到共振频率上，从而建立空间站。创建的程序被加载到控制单元的原型中，并在计算机程序中进行调试，之后被整合到整个项目中。
{"title":"Control System for Automatic Frequency Tunning of the Harmonic Station RF3 for Collider NICA","authors":"O. Brovko, E. Syresin, V. Morozova, D. Morozov, A. Karpuk, M. Yablochkin, A. Malyshev","doi":"10.1134/s1547477124701243","DOIUrl":"https://doi.org/10.1134/s1547477124701243","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The work is devoted to the creation of an automatic frequency control system for the harmonic station RF3 of the NICA collider. The special attention was paid to the main tasks and the algorithm of the station’s work. Based on the studied modes of station’s operation, a program for generating control pulses was developed. They are used for moving the tuners which set up the station to the resonant frequency. The created program was loaded into the prototype of the control unit and debugged in the computer program, after that it was integrated into the general project.</p>","PeriodicalId":730,"journal":{"name":"Physics of Particles and Nuclei Letters","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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