NSC KIPT Linux cluster for computing within the CMS physics program

The architecture of the NSC KIPT specialized Linux cluster constructed for carrying out work on CMS physics simulations and data processing is described. The configuration of the portable batch system (PBS) on the cluster is outlined. Capabilities of the cluster in its current configuration to perform CMS physics simulations are pointed out

On the multipurpose use of a portable neutron source

The possibility of creating a multipurpose complex for generating a reference field of thermal neutrons based on a portable neutron source (PNS) is considered. It has been shown that our method can be used to detect fissile materials without determining their isotopic composition during an inspection of the hand luggage of passengers, mail,etc. The PNS multipurpose complex will allow to indirectly indicating the possible presence of chemical explosives in the test samples, as well as cadmium and boron, which possibly hide fissile elements from detection. The paper gives recommendations on the use of the most effective instruments and equipment.Розглянута можливість створення багатофункціонального комплексу для генерування опорного поля теплових нейтронів на базі портативного джерела нейтронів (ПДН). Показано, що розробка може бути використана для виявлення матеріалів, що діляться, без визначення їх ізотопного складу при огляді ручної поклажі пасажирів, поштових відправлень і т. п. Крім того, комплекс ПДН дозволить побічно вказати на можливу присутність у досліджуваному об’ємі хімічної вибухової речовини, а також кадмію і бору, які можливо приховують елементи, що діляться, від виявлення. Дані рекомендації по застосуванню найбільш ефективних приладів та обладнання.Рассмотрена возможность создания многофункционального комплекса для генерации опорного поля тепловых нейтронов на основе портативного источника нейтронов (ПИН). Показано, что разработку можно использовать для обнаружения делящихся материалов без определения их изотопного состава при досмотре ручной клади пассажиров, почты и т. д. Кроме того, комплекс ПИН позволит косвенно указывать на возможное присутствие в исследуемом объеме химического взрывчатого вещества, а также кадмия и бора, которые, возможно, скрывают делящиеся элементы от обнаружения. Даны рекомендации по использованию наиболее эффективных инструментов и оборудования

Erratum to: A possible evidence of observation of two mixed phases in nuclear collisions

Using an advanced version of the hadron resonance gas model we have found several remarkable irregularities at chemical freeze-out. The most prominent of them are two sets of highly correlated quasi-plateaus in the collision energy dependence of the entropy per baryon, total pion number per baryon, and thermal pion number per baryon which we found at center of mass energies 3.6-4.9 GeV and 7.6-10 GeV. The low energy set of quasi-plateaus was predicted a long time ago. On the basis of the generalized shockadiabat model we demonstrate that the low energy correlated quasi-plateaus give evidence for the anomalous thermodynamic properties of the mixed phase at its boundary to the quark-gluon plasma. The question is whether the high energy correlated quasi-plateaus are also related to some kind of mixed phase. In order to answer this question we employ the results of a systematic meta-analysis of the quality of data description of 10 existing event generators of nucleus-nucleus collisions in the range of center of mass collision energies from 3.1 GeV to 17.3 GeV. These generators are divided into two groups: the first group includes the generators which account for the quark-gluon plasma formation during nuclear collisions, while the second group includes the generators which do not assume the quark-gluon plasma formation in such collisions. Comparing the quality of data description of more than a hundred of different data sets of strange hadrons by these two groups of generators, we find two regions of the equal quality of data description which are located at the center of mass collision energies 4.3-4.9 GeV and 10.-13.5 GeV. These two regions of equal quality of data description we interpret as regions of the hadron-quark-gluon mixed phase formation. Such a conclusion is strongly supported by the irregularities in the collision energy dependence of the experimental ratios of the Lambda hyperon number per proton and positive kaon number per Lambda hyperon. Although at the moment it is unclear, whether these regions belong to the same mixed phase or not, there are arguments that the most probable collision energy range to probe the QCD phase diagram (tri)critical endpoint is 12-14 GeV

A possible evidence of observation of two mixed phases in nuclear collisions

Using an advanced version of the hadron resonance gas model we have found several remarkable irregularities at chemical freeze-out. The most prominent of them are two sets of highly correlated quasi-plateaus in the collision energy dependence of the entropy per baryon, total pion number per baryon, and thermal pion number per baryon which we found at center of mass energies 3.6-4.9 GeV and 7.6-10 GeV. The low energy set of quasi-plateaus was predicted a long time ago. On the basis of the generalized shockadiabat model we demonstrate that the low energy correlated quasi-plateaus give evidence for the anomalous thermodynamic properties of the mixed phase at its boundary to the quark-gluon plasma. The question is whether the high energy correlated quasi-plateaus are also related to some kind of mixed phase. In order to answer this question we employ the results of a systematic meta-analysis of the quality of data description of 10 existing event generators of nucleus-nucleus collisions in the range of center of mass collision energies from 3.1 GeV to 17.3 GeV. These generators are divided into two groups: the first group includes the generators which account for the quark-gluon plasma formation during nuclear collisions, while the second group includes the generators which do not assume the quark-gluon plasma formation in such collisions. Comparing the quality of data description of more than a hundred of different data sets of strange hadrons by these two groups of generators, we find two regions of the equal quality of data description which are located at the center of mass collision energies 4.3-4.9 GeV and 10.-13.5 GeV. These two regions of equal quality of data description we interpret as regions of the hadron-quark-gluon mixed phase formation. Such a conclusion is strongly supported by the irregularities in the collision energy dependence of the experimental ratios of the Lambda hyperon number per proton and positive kaon number per Lambda hyperon. Although at the moment it is unclear, whether these regions belong to the same mixed phase or not, there are arguments that the most probable collision energy range to probe the QCD phase diagram (tri)critical endpoint is 12-14 GeV

Erratum to: A possible evidence of observation of two mixed phases in nuclear collisions

Using an advanced version of the hadron resonance gas model we have found several remarkable irregularities at chemical freeze-out. The most prominent of them are two sets of highly correlated quasi-plateaus in the collision energy dependence of the entropy per baryon, total pion number per baryon, and thermal pion number per baryon which we found at center of mass energies 3.6-4.9 GeV and 7.6-10 GeV. The low energy set of quasi-plateaus was predicted a long time ago. On the basis of the generalized shockadiabat model we demonstrate that the low energy correlated quasi-plateaus give evidence for the anomalous thermodynamic properties of the mixed phase at its boundary to the quark-gluon plasma. The question is whether the high energy correlated quasi-plateaus are also related to some kind of mixed phase. In order to answer this question we employ the results of a systematic meta-analysis of the quality of data description of 10 existing event generators of nucleus-nucleus collisions in the range of center of mass collision energies from 3.1 GeV to 17.3 GeV. These generators are divided into two groups: the first group includes the generators which account for the quark-gluon plasma formation during nuclear collisions, while the second group includes the generators which do not assume the quark-gluon plasma formation in such collisions. Comparing the quality of data description of more than a hundred of different data sets of strange hadrons by these two groups of generators, we find two regions of the equal quality of data description which are located at the center of mass collision energies 4.3-4.9 GeV and 10.-13.5 GeV. These two regions of equal quality of data description we interpret as regions of the hadron-quark-gluon mixed phase formation. Such a conclusion is strongly supported by the irregularities in the collision energy dependence of the experimental ratios of the Lambda hyperon number per proton and positive kaon number per Lambda hyperon. Although at the moment it is unclear, whether these regions belong to the same mixed phase or not, there are arguments that the most probable collision energy range to probe the QCD phase diagram (tri)critical endpoint is 12-14 GeV

Cross-sections for photonuclear reactions ⁹³Nb(γ,n)⁹²ᵐNb and ⁹³Nb(γ,n)⁹²ᵗNb in the end-point bremsstrahlung energies 36…91 MeV

The flux-weighted averaged over the energy range of bremsstrahlung spectrum from reaction threshold up to the maximum energy of γ-ray cross-sections of the ⁹³Nb(γ,n)⁹²ᵐNb and ⁹³Nb(γ,n)⁹²ᵗNb photonuclear reactions were determined by the gamma-activation method within the end-point bremsstrahlung energies Еγmax = 36…91 MeV. Activation of ⁹³Nb targets has been done by a bremsstrahlung flux using an electron beam at the linear accelerator LUE-40 at RDC “Accelerator” NSC KIPT. The γ-ray spectra of irradiated targets were registered using the HPGe detector with an energy resolution of 1.8 keV for the 1332 keV line ⁶⁰Co. To control the bremsstrahlung flux we used ⁿᵃᵗMo witness-targets and a reaction cross-section of ¹⁰⁰ Mo(γ,n)⁹⁹Mo. Obtained experimental cross-sections of the studied reactions are in good agreement with the theoretical values calculated within TALYS 1.9 code and the results of other authors. The averaged cross-sections of the ⁹³Nb(γ,n)⁹²ᵐNb and ⁹³Nb(γ,n)⁹²ᵗNb reactions in the energy range 35…45 MeV and > 70 MeV were obtained for the first time.Виміряні усереднені за гальмівним спектром перерізи фотоядерних реакцій ⁹³Nb(γ,n)⁹²ᵐNb і ⁹³Nb(γ,n)⁹²ᵗNb в енергетичному інтервалі від порога реакції до граничних енергій Еγmax = 36…91 MeV. Дослідження проведені на пучку лінійного прискорювача електронів ЛУЕ-40 НІК «Прискорювач» ННЦ ХФТІ з використанням мішеней ⁹³Nb та за допомогою гамма-активаційного методу. Спектри γ-випромінювання активованих зразків реєструвалися HPGe-детектором з енергетичним розрізненням 1,8 кеВ по лінії 1332 кеВ ⁶⁰Co. Для контролю потоку гальмівних γ-квантів використовувалися мішені-свідки з натурального молібдену і переріз реакції ¹⁰⁰Mo(γ,n)⁹⁹Mo. Експериментальні перерізи досліджуваних реакцій знаходяться в задовільному узгодженні з теоретичними значеннями, отриманими за допомогою програмного коду TALYS 1.9 з параметрами за замовчуванням. Перерізи реакцій ⁹³Nb(γ,n)⁹²ᵐNb і ⁹³Nb(γ,n)⁹²ᵗNb у діапазоні 35… 45 MэВ и >70 MэВ виміряні вперше.Измерены усредненные по тормозному γ-спектру сечения фотоядерных реакций ⁹³Nb(γ,n)⁹²ᵐNb и ⁹³Nb(γ,n)⁹²ᵗNb в энергетическом интервале от порога реакции до граничных энергий Еγmax = 36…91 MeV. Исследования проведены на пучке линейного ускорителя электронов ЛУЭ-40 НИК «Ускоритель» ННЦ ХФТИ с использованием мишеней ⁹³Nb и с применением гамма-активационного метода. Спектры γ-излучения облученных образцов регистрировались HPGe-детектором с энергетическим разрешением 1,8 кэВ по γ-линии 1332 кэВ ⁶⁰Co. Для контроля потока тормозных γ-квантов использованы мишени-свидетели из натурального молибдена и сечение реакции ¹⁰⁰Mo(γ,n)⁹⁹Mo. Экспериментальные сечения исследуемых реакций находятся в удовлетворительном согласии с теоретическими значениями, полученными при использовании программного кода TALYS 1.9 с параметрами по умолчанию. Сечения для реакций ⁹³Nb(γ,n)⁹²ᵐNb и ⁹³Nb(γ,n)⁹²ᵗNb в области 35…45 MэВ и > 70 MэВ измерены впервые

A possible evidence of observation of two mixed phases in nuclear collisions

Using an advanced version of the hadron resonance gas model we have found several remarkable irregularities at chemical freeze-out. The most prominent of them are two sets of highly correlated quasi-plateaus in the collision energy dependence of the entropy per baryon, total pion number per baryon, and thermal pion number per baryon which we found at center of mass energies 3.6-4.9 GeV and 7.6-10 GeV. The low energy set of quasi-plateaus was predicted a long time ago. On the basis of the generalized shock-adiabat model we demonstrate that the low energy correlated quasi-plateaus give evidence for the anomalous thermodynamic properties of the mixed phase at its boundary to the quark-gluon plasma. The question is whether the high energy correlated quasi-plateaus are also related to some kind of mixed phase. In order to answer this question we employ the results of a systematic meta-analysis of the quality of data description of 10 existing event generators of nucleus-nucleus collisions in the range of center of mass collision energies from 3.1 GeV to 17.3 GeV. These generators are divided into two groups: the first group includes the generators which account for the quark-gluon plasma formation during nuclear collisions, while the second group includes the generators which do not assume the quark-gluon plasma formation in such collisions. Comparing the quality of data description of more than a hundred of different data sets of strange hadrons by these two groups of generators, we find two regions of the equal quality of data description which are located at the center of mass collision energies 4.3-4.9 GeV and 10.-13.5 GeV. These two regions of equal quality of data description we interpret as regions of the hadron-quark-gluon mixed phase formation.Comment: 11 pages, figures. arXiv admin note: text overlap with arXiv:1510.0309