206 research outputs found
Quark deconfinement in compact stars through sexaquark condensation
No full textIn this contribution, we present for the first time a scenario according to
which early quark deconfinement in compact stars is triggered by the
Bose-Einstein condensation (BEC) of a light sexaquark (S) with a mass
MeV, that has been suggested as a candidate particle to explain the
baryonic dark matter in the Universe. The onset of S BEC marks the maximum mass
of hadronic neutron stars and it occurs when the condition for the baryon
chemical potential is fulfilled in the center of the star,
corresponding to . In the gravitational
field of the star the density of the BEC of the S increases until a new state
of the matter is attained, where each of the S-states got dissociated into a
triplet of color-flavor-locked (CFL) diquark states. These diquarks are the
Cooper pairs in the color superconducting CFL phase of quark matter, so that
the developed scenario corresponds to a BEC-BCS transition in strongly
interacting matter. For the description of the CFL phase, we develop here for
the first time the three-flavor extension of the density-functional formulation
of a chirally symmetric Lagrangian model of quark matter where confining
properties are encoded in a divergence of the scalar self-energy at low
densities and temperatures.Comment: 27 pages, 8 figures, Contribution to the Book "New Phenomena and New
States of Matter in the Universe. From Quarks to Cosmos" edited by C. A. Z.
Vasconcellos, P. O. Hess and T. Bolle
How does dark matter affect compact star properties and high density constraints of strongly interacting matter
No full textWe study the impact of asymmetric bosonic dark matter on neutron starproperties, including possible changes of tidal deformability, maximum mass,radius, and matter distribution inside the star. The conditions at which darkmatter particles tend to condensate in the star's core or create an extendedhalo are presented. We show that dark matter condensed in a core leads to adecrease of the total gravitational mass and tidal deformability compared to apure baryonic star, which we will perceive as an effective softening of theequation of state. On the other hand, the presence of a dark matter haloincreases those observable quantities. Thus, observational data on compactstars could be affected by accumulated dark matter and, consequently,constraints we put on strongly interacting matter at high densities. To confirmthe presence of dark matter in the compact star's interior, and to break thedegeneracy between the effect of accumulated dark matter and stronglyinteracting matter properties at high densities, several astrophysical and GWtests are proposed.<br
Methods and tools for organizing computer systems toprotect stationary physical objects using GSM signaling
No full textКваліфікаційна робота магістра присвячена дослідженню методів і
засобів організації комп’ютерних систем захисту фізичних стаціонарних
об’єктів на основі GSM-сигналізації.
У роботі спроектовано архітектуру комп’ютерної системи захисту
фізичних стаціонарних об’єктів на основі мікроконтролерів ESP32 та
ESP32-CAM з підключенням сенсорів газу, температури і вологості,
датчика руху і сумісної камери з роздільною здатністю 2Мп, що дало
можливість підвищити функціональність системи за рахунок інтеграції
програмної моделі інтелектуального розпізнавання облич.
Окрім цього, запропоновано архітектуру нейромережі для
забезпечення функції розпізнавання облич, що використовує топологію
згорткової нейронної мережі і дає змогу оптимізувати використання
апаратних ресурсів за рахунок використання лише одного нейрону у
вихідному шарі, розроблено загальний і частковий алгоритми роботи
комп’ютерної системи захисту фізичних стаціонарних об’єктів на основі
GSM-сигналізації, проведено налаштування параметрів для
функціонування мікроконтролерів ESP32 та ESP32-САМ при управлінні
системою формування сповіщень GSM-модуля.The master's qualification work is devoted to the study of methods and
means of organizing computer systems for protecting physical stationary objects
based on GSM-alarming.
The work designs the architecture of a computer system for protecting
physical stationary objects based on ESP32 and ESP32-CAM microcontrollers
with the connection of gas, temperature and humidity sensors, a motion sensor
and a compatible camera with a resolution of 2MP, which made it possible to
increase the functionality of the system by integrating a software model for
intelligent face recognition.
In addition, a neural network architecture is proposed to provide the face
recognition function, which uses the topology of a convolutional neural network
and allows you to optimize the use of hardware resources by using only one
neuron in the output layer, general and partial algorithms for the operation of a
computer system for protecting physical stationary objects based on GSM-
alarming have been developed, and parameters for the operation of ESP32 and
ESP32-CAM microcontrollers when controlling the GSM module notification
generation system have been set.ВСТУП 8
РОЗДІЛ 1 АНАЛІЗ GSM-ТЕХНОЛОГІЇ ПЕРЕДАЧІ ДАНИХ У
СИСТЕМАХ ЗАХИСТУ СТАЦІОНАРНИХ ОБ’ЄКТІВ 13
1.1. Аналіз принципів функціонування GSM-мереж 13
1.2. Аналіз існуючих рішень організації систем безпеки фізичних
стаціонарних об’єктів 20
1.2.1. Аналіз системи безпеки на основі Raspberry PI, GSM та Bluetooth 24
1.2.2. Аналіз системи GSM-сигналізації на основі Raspberry PI та Java 25
1.3. Висновки до розділу 27
РОЗДІЛ 2 ПРОЕКТУВАННЯ КОМП’ЮТЕРНОЇ СИСТЕМИ ЗАХИСТУ
СТАЦІОНАРНИХ ФІЗИЧНИХ ОБ’ЄКТІВ З ВИКОРИСТАННЯМ GSM-
СИГНАЛІЗАЦІЇ 29
2.1. Архітектура комп’ютерної системи захисту стаціонарних фізичних
об’єктів 29
2.2. Обґрунтування і вибір апаратного забезпечення комп’ютерної системи
захисту фізичних стаціонарних об’єктів на основі GSM-сигналізації 31
2.2.1. Контролер управління пристроями GSM-сигналізації 31
2.2.2. Функції GSM-модуля у системі забезпечення безпеки фізичних
стаціонарних об’єктів 32
2.2.3. Сенсор руху, як тригер активації GSM-сигналізації 34
2.2.4. Сенсор газу як засіб сповіщувач небезпечної ситуації 36
2.2.5. Сенсор вимірювання температури і вологості у системі GSM-
сигналізації 40
2.2.6. Модуль ESP32-СAM та камера OV2640, як апаратна складова
інтелектуального розпізнавання облич 41
2.3. Проектування схем з’єднання та інсталяція компонентів системи
GSM-сигналізації 47
2.4. Висновки до розділу 50
РОЗДІЛ 3 ІМПЛЕМЕНТАЦІЯ ПРОГРАМНОЇ МОДЕЛІ
РОЗПІЗНАВАННЯ ОБРАЗІВ ТА СИСТЕМНОГО ПРОГРАМНОГО
ЗАБЕЗПЕЧЕННЯ GSM-СИГНАЛІЗАЦІЇ 52
3.1. Нейронна мережа для ідентифікації зображення з камери системи
GSM-сигналізації 52
3.2. Проектування топології нейронної мережі для реалізації функції
розпізнавання обличчя системи GSM-сигналізації 61
3.3. Розробка алгоритму роботи системи захисту стаціонарних об’єктів на
основі GSM-сигналізації 64
3.4. Встановлення та налаштування бібліотек ESP32-CAM 67
3.5. Висновки до розділу 74
РОЗДІЛ 4 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ
СИТУАЦІЯХ 75
4.1. Охорона праці 75
4.2. Засоби захисту персоналу від уражень радіації 78
ВИСНОВКИ 82
СПИСОК ВИКОРИСТАНИХ ДЖЕРЕЛ 84
ДОДАТОК А ТЕКСТ НАУКОВИХ ПУБЛІКАЦІЙ КВАЛІФІКАЦІЙНОЇ
РОБОТИ МАГІСТРА 8
What is the nature of the HESS J1731-347 compact object?
No full textOnce further confirmed in future analyses, the radius and mass measurement ofHESS J1731-347 with and will be among the lightest and smallest compactobjects ever detected. This raises many questions about its nature and opens upthe window for different theories to explain such a measurement. In thisarticle, we use the information from Doroshenko et al. (2022) on the mass,radius, and surface temperature together with the multimessenger observationsof neutron stars to investigate the possibility that HESS J1731-347 is one ofthe lightest observed neutron star, a strange quark star, a hybrid star with anearly deconfinement phase transition, or a dark matter-admixed neutron star.The nucleonic and quark matter are modeled within realistic equation of states(EOSs) with a self-consistent calculation of the pairing gaps in quark matter.By performing the joint analysis of the thermal evolution and mass-radiusconstraint, we find evidence that within a 1 confidence level, HESSJ1731-347 is consistent with the neutron star scenario with the soft EOS aswell as with a strange and hybrid star with the early deconfinement phasetransition with a strong quark pairing and neutron star admixed with darkmatter.<br
The effects of self-interacting bosonic dark matter on neutron star properties
No full textWe propose a model of asymmetric bosonic dark matter (DM) with self-repulsion
mediated by the vector field coupled to the complex scalar particles. By
adopting the two-fluid formalism, we study different DM distribution regimes,
either, fully condensed inside the core of a star or, otherwise, distributed in
a dilute halo around a neutron star (NS). We show that DM condensed in a core
leads to a decrease of the total gravitational mass, radius and tidal
deformability compared to a pure baryonic star with the same central density,
which we will perceive as an effective softening of the equation of state
(EoS). On the other hand, the presence of a DM halo increases the tidal
deformability and total gravitational mass. As a result, an accumulated DM
inside compact stars could mimic an apparent stiffening of strongly interacting
matter equation of state and constraints we impose on it at high densities.
From the performed analysis of the effect of DM particles in a MeV-GeV
mass-scale, interaction strength, and relative DM fractions inside NSs we
obtained a rigorous constraint on model parameters. Finally, we discuss several
smoking guns of the presence of DM that are free from the above mentioned
apparent modification of the strongly interacting matter equation of state.
With this we could be probed with the future astrophysical and gravitational
wave (GW) surveys.Comment: 14 pages, 5 figure
Neutral pion production at midrapidity in pp and Pb-Pb collisions at root(NN)-N-S=2.76 TeV
No full textInvariant yields of neutral pions at midrapidity in the transverse momentum range 0.6 < pT < 12 GeV/c measured in Pb-Pb collisions at root(NN)-N-s = 2.76 TeV are presented for six centrality classes. The pp reference spectrum was measured in the range 0.4 < pT < 10 GeV/c at the same center-of-mass energy. The nuclear modification factor, R-AA, shows a suppression of neutral pions in central Pb-Pb collisions by a factor of up to about 8-10 for 5 less than or similar to p(T) less than or similar to 7 GeV/c. The presented measurements are compared with results at lower center-of-mass energies and with theoretical calculations
Measurement of quarkonium production at forward rapidity in collisions at root s = 7 TeV
No full textThe inclusive production cross sections at forward rapidity of , , (1S) and (2S) are measured in collisions at with the ALICE detector at the LHC. The analysis is based on a data sample corresponding to an integrated luminosity of 1.35 pb. Quarkonia are reconstructed in the dimuon-decay channel and the signal yields are evaluated by fitting the invariant mass distributions. The differential production cross sections are measured as a function of the transverse momentum and rapidity , over the ranges GeV/c for , GeV/c for all other resonances and for . The measured cross sections integrated over and , and assuming unpolarized quarkonia, are: b, b, nb and nb, where the first uncertainty is statistical and the second one is systematic. The results are compared to measurements performed by other LHC experiments and to theoretical models
K*(892)(0) and phi(1020) production in Pb-Pb collisions at root s(NN)=2.76 TeV
No full textThe yields of the K*(892)(0) and phi(1020) resonances are measured in Pb-Pb collisions at root s(NN) = 2.76 TeV through their hadronic decays using the ALICE detector. The measurements are performed in multiple centrality intervals at mid-rapidity (vertical bar y vertical bar < 0.5) in the transverse-momentum ranges 0.3 < p(T) < 5 GeV/c for the K*(892)(0) and 0.5 < p(T) < 5 GeV/c for the phi(1020). The yields of K*(892)(0) are suppressed in central Pb-Pb collisions with respect to pp and peripheral Pb-Pb collisions (perhaps due to rescattering of its decay products in the hadronic medium), while the longer-lived phi(1020) meson is not suppressed. These particles are also used as probes to study the mechanisms of particle production. The shape of the pT distribution of the phi(1020) meson, but not its yield, is reproduced fairly well by hydrodynamic models for central Pb-Pb collisions. In central Pb-Pb collisions at low and intermediate p(T), the p/phi(1020) ratio is flat in p(T), while the p/pi and phi(1020)/pi ratios show a pronounced increase and have similar shapes to each other. These results indicate that the shapes of the p(T) distributions of these particles in central Pb-Pb collisions are determined predominantly by the particle masses and radial flow. Finally, phi(1020) production in Pb-Pb collisions is enhanced, with respect to the yield in pp collisions and the yield of charged pions, by an amount similar to the Lambda and Xi
Centrality dependence of π, K, and p production in Pb-Pb collisions at TeV
No full textIn this paper measurements are presented of pi(+/-), K-+/-, p, and (p) over bar production at midrapidity (vertical bar y vertical bar < 0.5), in Pb-Pb collisions at root s(NN) = 2.76 TeV as a function of centrality. The measurement covers the transverse-momentum (p(T)) range from 100, 200, and 300 MeV/c up to 3, 3, and 4.6 GeV/c for pi, K, and p, respectively. The measured p(T) distributions and yields are compared to expectations based on hydrodynamic, thermal and recombination models. The spectral shapes of central collisions show a stronger radial flow than measured at lower energies, which can be described in hydrodynamic models. In peripheral collisions, the p(T) distributions are not well reproduced by hydrodynamic models. Ratios of integrated particle yields are found to be nearly independent of centrality. The yield of protons normalized to pions is a factor similar to 1.5 lower than the expectation from thermal models
Measurement of quarkonium production at forward rapidity in pp√s=7 TeV
No full textThe inclusive production cross sections at forward rapidity of , , (1S) and (2S) are measured in collisions at with the ALICE detector at the LHC. The analysis is based on a data sample corresponding to an integrated luminosity of 1.35 pb. Quarkonia are reconstructed in the dimuon-decay channel and the signal yields are evaluated by fitting the invariant mass distributions. The differential production cross sections are measured as a function of the transverse momentum and rapidity , over the ranges GeV/c for , GeV/c for all other resonances and for . The measured cross sections integrated over and , and assuming unpolarized quarkonia, are: b, b, nb and nb, where the first uncertainty is statistical and the second one is systematic. The results are compared to measurements performed by other LHC experiments and to theoretical models
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