Λ-hipernuklearna spektroskopija visokog razlučivanja reakcijom (e,e’K+)

(for the E01-011 Collaboration) The E01-011 (HKS) experiment is the second-generation hypernuclear spectroscopy experiment by the (e,e\u27K+) reaction at the Thomas Jefferson National Accelerator Facility (JLab). This is the continuation of the hypernuclear physics program at JLab Hall C established by the E89-009 (HNSS) experiment which demonstrated feasibility of electroproduction of hypernuclei with sub-MeV resolution. The immediate goal of the HKS experiment is to study hypernuclei in the medium-heavy region. To achieve this goal, the new high-resolution kaon spectrometer (HKS) was constructed and built, and new method in tagging the scattered electrons, the so called Tilt method, was implemented. Preliminary high-resolution spectra of 7Λ He, 12Λ B and 28Λ Al hypernuclei are presented and discussed.Mjerenja E01-011 (HKS) su druga generacija istraživanja u hipernuklearnoj spektroskopiji reakcijom (e,e’K+) u Thomas Jefferson National Accelerator Facility (JLab). To je nastavak programa istraživanja u hipernuklearnoj fizici u JLabu Hall C započet mjerenjima E89-009 (HNSS), koja su pokazala mogućnost elektrotvorbe hiperjezgri uz razlučivanje bolje od 1 MeV. Neposredan cilj mjerenja HKS bio je proučavanje srednje teških hiperjezgri. Radi toga sagrađen je nov kaonski spektrometar (HKS) visokog različivanja i uvedena je nova metoda za označavanje raspršenih elektrona, tzv. metoda naklona (Tilt method). Opisuju se i raspravljaju prethodni spektri visokog razlučivanja hiperjezgri 7 ΛHe, 12 Λ B and 28 Λ Al

High-resolution a hypernuclear Λ hypernuclear spectroscopy by the (e,e'K+) reaction

The E01-011 (HKS) experiment is the second-generation hypernuclear spectroscopy experiment by the (e,e'K+) reaction at the Thomas Jefferson National Accelerator Facility (JLab). This is the continuation of the hypernuclear physics program at JLab Hall C established by the E89-009 (HNSS) experiment which demonstrated feasibility of electroproduction of hypernuclei with sub-MeV resolution. The immediate goal of the HKS experiment is to study hypernuclei in the medium-heavy region. To achieve this goal, the new high-resolution kaon spectrometer (HKS) was constructed and built, and new method in tagging the scattered electrons, the so called Tilt method, was implemented. Preliminary high-resolution spectra of ^7Λ He, ^12Λ B and ^28Λ Al hypernuclei are presented and discussed

High-resolution a hypernuclear Λ hypernuclear spectroscopy by the (e,e'K+) reaction

The E01-011 (HKS) experiment is the second-generation hypernuclear spectroscopy experiment by the (e,e'K+) reaction at the Thomas Jefferson National Accelerator Facility (JLab). This is the continuation of the hypernuclear physics program at JLab Hall C established by the E89-009 (HNSS) experiment which demonstrated feasibility of electroproduction of hypernuclei with sub-MeV resolution. The immediate goal of the HKS experiment is to study hypernuclei in the medium-heavy region. To achieve this goal, the new high-resolution kaon spectrometer (HKS) was constructed and built, and new method in tagging the scattered electrons, the so called Tilt method, was implemented. Preliminary high-resolution spectra of ^7Λ He, ^12Λ B and ^28Λ Al hypernuclei are presented and discussed

The pinning quantum phase transition in a Tonks Girardeau gas: diagnostics by ground state fidelity and the Loschmidt echo

We study the pinning quantum phase transition in a Tonks-Girardeau gas, both in equilibrium and out-of-equilibrium, using the ground state fidelity and the Loschmidt echo as diagnostic tools. The ground state fidelity (GSF) will have a dramatic decrease when the atomic density approaches the commensurate density of one particle per lattice well. This decrease is a signature of the pinning transition from the Tonks to the Mott insulating phase. We study the applicability of the fidelity for diagnosing the pinning transition in experimentally realistic scenarios. Our results are in excellent agreement with recent experimental work. In addition, we explore the out of equilibrium dynamics of the gas following a sudden quench with a lattice potential. We find all properties of the ground state fidelity are reflected in the Loschmidt echo dynamics i.e., in the non equilibrium dynamics of the Tonks-Girardeau gas initiated by a sudden quench of the lattice potential

Razvoj rane pismenosti u srpskim vrtićima - osnovni resursi i s njima povezana praksa

This study explores the basic resources available in kindergartens and practices of kindergarten teachers that literature recognizes as supportive for the development of emergent literacy in 3-5 year-old children. 374 kindergarten teachers from 10 different districts at the territory of the city of Belgrade filled in a questionnaire on the frequency of storybook reading, the number and types of books available to children and their use of electronic media (e.g. television programmes, cartoons) in their everyday practices with children. The results indicate that current educational programmes in Serbia do not explicitly support the development of emergent literacy in 3-5 year-old children. Although teacher initiated reading is embedded in daily kindergarten activities, our kindergartens hardly fulfill the necessary conditions with respect to print rich environment (1-3 books on the average, compared to the minimum of 5). TV sets are present in 85% of kindergartens, with 45% directly available to children in their rooms. Although children mainly watch TV 1-3 times per week, it is used mostly for entertainment, with only 34% of teachers using it as an educational tool in the interaction with children. Future directions of research on practices and beliefs related to emergent literacy, both in kindergartens and at home, are discussed.Ovo istraživanje bavi se osnovnim resursima koji su na raspolaganju vrtićima i vaspitačima, a pominju se u literaturi kao podrška razvoju rane pismenosti kod dece uzrasta od 3 do 5 godina. Uzorak je obuhvatio 374 vaspitača iz deset različitih opština na teritoriji grada Beograda koji su popunili upitnik o učestalosti čitanja priča, broju i vrsti knjiga koje su deci na raspolaganju i upotrebi elektronskih medija (na primer, televizijskih programa, crtanih filmova) u svakodnevnom radu s decom. Rezultati istraživanja pokazuju da sadašnji obrazovni programi u Srbiji eksplicitno ne podržavaju razvoj rane pismenosti kod dece uzrasta od 3 do 5 godina. Iako čitanje koje inicira vaspitač predstavlja sastavni deo svakodnevnih aktivnosti u vrtiću, naši vrtići jedva da ispunjavaju neophodne uslove za obezbeđivanje okruženja bogatog štampanim materijalima (jedna do tri knjige u proseku, u poređenju sa minimum pet). Televizori postoje u 85% vrtića, dok su u 45% direktno pristupačni deci u njihovim sobama. Iako deca uglavnom gledaju televiziju jedan do tri puta nedeljno, ona se u najvećem broju slučajeva koristi za zabavu, dok samo 34% vaspitača televizor koristi kao obrazovno sredstvo u interakciji s decom. U zaključku se diskutuju mogućnosti za buduća istraživanja o praksi i stavovima povezanim sa ranom pismenošću, kako u vrtiću, tako i kod kuće

Loschmidt echo in one-dimensional interacting Bose gases

We explore Loschmidt echo in two regimes of one-dimensional (1D) interacting Bose gases: the strongly interacting Tonks-Girardeau (TG) regime, and the weakly-interacting mean-field regime. We find that the Loschmidt echo of a TG gas decays as a Gaussian when small perturbations are added to the Hamiltonian (the exponent is proportional to the number of particles and the magnitude of a small perturbation squared). In the mean-field regime the Loschmidt echo decays faster for larger interparticle interactions (nonlinearity), and it shows richer behavior than the TG Loschmidt echo dynamics, with oscillations superimposed on the overall decay.Comment: Comparison between Tonks-Girardeau and mean-field fidelities corrected; see new Figure 4 and the "Note added". New references are include

Exploring the factor structure of the parent reading belief inventory (PRBI): Example of Serbia

In the present study we explored the core factor structure originally proposed by the developer of the Parent Reading Belief Inventory (PRBI) DeBaryshe (DeBaryshe & Binder, 1994; DeBaryshe, 1995). The PRBI was developed to assess and explore parents' beliefs about reading aloud to their children, measuring parents' attitudes and perceptions about how children learn, the content of their learning and parental efficacy in the process. The PRBI is supposed to have 7 underlying subscales and a total score. Using a sample of 227 parents in Serbia our analyses showed internal consistency estimates were not in line with those reported by the authors of the PRBI. Using confirmatory factor analysis the subscale models showed substantial variance in how well they fit. Better fit was found for the overall models for the entire PRBI scale. Among them, the correlated factors model exhibited the best fit indices. Limitations and future research are discussed

Eksperimentalno istraživanje elektroprodukcije hiperjezgri spektrima visoke rezolucije

Λ hypernuclear spectroscopy by the (e, e′K+) reaction is a powerful tool to investigate ΛN interaction because this reaction excites various states up to deep inside of hypernucleus and sub-MeV resolution can be achieved thanks to the high quality primary electron beam from CEBAF at JLab. The second generation hypernuclear spectroscopy at JLab Hall C, E01-011 experiment, was successfully performed in the summer of 2005 introducing High resolution Kaon Spectrometer (HKS) and a new configuration for scattered electron spectrometer. These unique techniques significantly improved both energy resolution and hypernuclear tagging efficiency, and we succeeded to study various hypernuclei including 12ΛB and 28ΛAl with high resolution and sufficient statistics for the first time by this reaction.Hiperjezgra se dobije zamjenom jednog ili više nukleona u jezgri s hiperonom, npr. s Λ, Σ ili Ξ. Budući da hiperon osim u i d kvarka ima i s kvark, Λ u nuklearni medij uvodi novi stupanj slobode - stranost. Zbog novog stupnja slobode Λ se razlikuje od nukleona zbog čega nema Paulijevog blokiranja što omogućuje proučavanje duboko vezanih stanja. Na Thomas Jefferson National Accelerator Facility postoji više godina široka međunarodna kolaboracija koja je po prvi put u svijetu demonstrirala mogućnosti tvorbe hiperjezgri elektroprodukcijom. Korištenje procesa elektroprodukcije dobro definiranih jednočesetičnih stanja hiperona u jezgri, a koja su do sada proučavana kroz (K−,π−) i (π+,K+) reakcije na BNL-u i KEK-PS, novi je smjer u izučavanju hiperjezgri. Predstavljeni će biti hipernuklearna spekstroskopija (e,e’K+) reakcijom, eksperimentalni postav i analiza podataka eksperimenta E01-011. Prikazani će biti preliminarni rezultati visokorezolucijskih spektara 12ΛB te po prvi put ikad spektar 28ΛAl hiperjezgri dobiveni elektroprodukcijom

Big Data Analytics and the Social Web: a Tutorial for the Social Scientist

The social web or web 2.0 has become the biggest and most accessible repository of data about human (social) behavior in history. Due to a knowledge gap between big data analytics and established social science methodology, this enormous source of information, has yet to be exploited for new and interesting studies in various social and humanities related fields. To make one step towards closing this gap, we provide a detailed step-by-step tutorial on some of the most important web mining and analytics methods on a real-world study of Croatia’s biggest political blogging site. The tutorial covers methods for data retrieval, data conversion, cleansing and organization, data analysis (natural language processing, social and conceptual network analysis) as well as data visualization and interpretation. All tools that have been implemented for the sake of this study, data sets through the various steps as well as resulting visualizations have been published on-line and are free to use. The tutorial is not meant to be a comprehensive overview and detailed description of all possible ways of analyzing data from the social web, but using the steps outlined herein one can certainly reproduce the results of the study or use the same or similar methodology for other datasets. Results of the study show that a special kind of conceptual network generated by natural language processing of articles on the blogging site, namely a conceptual network constructed by the rule that two concepts (keywords) are connected if they were extracted from the same article, seem to be the best predictor of the current political discourse in Croatia when compared to the other constructed conceptual networks. These results indicate that a comprehensive study has to be made to investigate this conceptual structure further with an accent on the dynamic processes that have led to the construction of the network