Indirect measurement of O-17(p,alpha)N-14 cross section at ultra-low energies
Sergi, M. L.; Spitaleri, C.; Coc, A.; Mukhamedzhanov, A.; Burjan, Václav; Cherubini, S.; Crucilla, V.; Gulino, M.; Hammache, F.; Hons, Zdeněk; Irgaziev, B.; Kiss, G. G.; Kroha, Václav; La Cognata, M.; Lamia, L.; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; de Sereville, N.; Somorjai, E.; Tudisco, S.; Tumino, A.
2010 - anglický The indirect measurement of O-17(p,alpha)N-14 cross section was performed by means of the Trojan Horse Method. This approach allowed to investigate the ultra-low energy range (E-c.m.= 0-300 keV) relevant for several astrophysics environments, where two resonant levels of F-18 at E-c.m.(R) = 65 keV and E-c.m.(R) = 183 keV play a significant role in the reaction rate determination. Klíčová slova: astrophysics; nuclear reaction; reaction rates Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Indirect measurement of O-17(p,alpha)N-14 cross section at ultra-low energies

The indirect measurement of O-17(p,alpha)N-14 cross section was performed by means of the Trojan Horse Method. This approach allowed to investigate the ultra-low energy range (E-c.m.= 0-300 keV) ...

Sergi, M. L.; Spitaleri, C.; Coc, A.; Mukhamedzhanov, A.; Burjan, Václav; Cherubini, S.; Crucilla, V.; Gulino, M.; Hammache, F.; Hons, Zdeněk; Irgaziev, B.; Kiss, G. G.; Kroha, Václav; La Cognata, M.; Lamia, L.; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; de Sereville, N.; Somorjai, E.; Tudisco, S.; Tumino, A.
Ústav jaderné fyziky, 2010

Astrophysical Reaction Rates Obtained By Indirect Techniques
Tribble, R. E.; Al-Abdullah, T.; Alharbi, A.; Aysto, J.; Banu, A.; Burjan, Václav; Carstoiu, F.; Chen, X.; Clark, H. L.; Davidson, T.; Fu, C.; Gagliardi, C. A.; Hardy, J. C.; Iacob, V. E.; Jokinen, J.; Kroha, Václav; Lui, Y. W.; McCleskey, M.; Mukhamedzhanov, A.; Nica, N.; Park, H.; Roeder, B. T.; Saastamoinen, A.; Simmons, E.; Tabacaru, G.; Tokimoto, Y.; Trache, L.; Woods, P. J.; Zhai, Y.
2010 - anglický ndirect techniques have been used to obtain information about reaction rates for several proton capture reactions that occur on short-lived nuclei. The techniques used to carry out the measurements are reviewed and the results obtained are presented. Also future prospects for further measurements with a new facility, T-REX, are discussed. Klíčová slova: nuclear astophysics; explosive nucleosynthesis; proton capture Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Astrophysical Reaction Rates Obtained By Indirect Techniques

ndirect techniques have been used to obtain information about reaction rates for several proton capture reactions that occur on short-lived nuclei. The techniques used to carry out the measurements ...

Tribble, R. E.; Al-Abdullah, T.; Alharbi, A.; Aysto, J.; Banu, A.; Burjan, Václav; Carstoiu, F.; Chen, X.; Clark, H. L.; Davidson, T.; Fu, C.; Gagliardi, C. A.; Hardy, J. C.; Iacob, V. E.; Jokinen, J.; Kroha, Václav; Lui, Y. W.; McCleskey, M.; Mukhamedzhanov, A.; Nica, N.; Park, H.; Roeder, B. T.; Saastamoinen, A.; Simmons, E.; Tabacaru, G.; Tokimoto, Y.; Trache, L.; Woods, P. J.; Zhai, Y.
Ústav jaderné fyziky, 2010

Indirect Approach To The H-2(d,p)H-3 Reaction Study
Sparta, R.; Pizzone, R. G.; Spitaleri, C.; Aliotta, M.; Burjan, Václav; Cherubini, S.; Crucilla, V.; Gulino, M.; Hons, Zdeněk; Kiss, G. G.; Kroha, Václav; La Cognata, M.; Lamia, L.; McCleskey, M.; Mrázek, Jaromír; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; Sergi, M. L.; Trache, L.; Tumino, A.
2010 - anglický In order to understand primordial and stellar nucleosynthesis, we have studied H-2(d,p)H-3 reaction at 0.4 MeV down to astrophysical energies. Knowledge of its S-factor is interesting also to plan reactions for fusion reactors to produce energy. The H-2(d,p)H-3 reaction has been studied through the Trojan Horse Method applied to the three-body reaction H-2(He-3,pt)H, at beam energy of 17 MeV. Once selection of protons and tritons detected in coincidence and the selection of quasi-free events, the obtained S-factor is compared with direct measurements. Such data are in agreement with the direct ones and a pole invariance test has been obtained comparing the present results with another H-2(d,p)H-3 THM measurements, where a different spectator particle was employed. Klíčová slova: nuclear astrohphysics; Trojan Horse; Big Bang nucleosynthesis Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Indirect Approach To The H-2(d,p)H-3 Reaction Study

In order to understand primordial and stellar nucleosynthesis, we have studied H-2(d,p)H-3 reaction at 0.4 MeV down to astrophysical energies. Knowledge of its S-factor is interesting also to plan ...

Sparta, R.; Pizzone, R. G.; Spitaleri, C.; Aliotta, M.; Burjan, Václav; Cherubini, S.; Crucilla, V.; Gulino, M.; Hons, Zdeněk; Kiss, G. G.; Kroha, Václav; La Cognata, M.; Lamia, L.; McCleskey, M.; Mrázek, Jaromír; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; Sergi, M. L.; Trache, L.; Tumino, A.
Ústav jaderné fyziky, 2010

Spectroscopy of Medium-mass Hypernuclear Production
Motoba, T.; Bydžovský, Petr; Sotona, Miloslav; Itonaga, K.; Ogawa, K.; Hashimoto, O.
2010 - anglický Theoretical hypernuclear photoproduction spectra are demonstrated by choosing typical medium-heavy nuclear targets such as Si-28, Ca-40, and Cr-52. The predictions provide us with interesting opportunities of spectroscopic study beyond p-shell on the dynamical coupling between a hyperon and nuclear core excitations. Klíčová slova: hypernuclear photoproduction; DWIA; unnatural parity states Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Spectroscopy of Medium-mass Hypernuclear Production

Theoretical hypernuclear photoproduction spectra are demonstrated by choosing typical medium-heavy nuclear targets such as Si-28, Ca-40, and Cr-52. The predictions provide us with interesting ...

Motoba, T.; Bydžovský, Petr; Sotona, Miloslav; Itonaga, K.; Ogawa, K.; Hashimoto, O.
Ústav jaderné fyziky, 2010

Influence of Plastic Deformation on the Residual Stress Distribution and Fatigue Behaviour of High Strength Steels Welds
Mráz, Ľ.; Karlsson, L.; Hamak, I.; Mikula, Pavol; Vrána, Miroslav
2010 - anglický The effects of plastic deformation and cyclic loading on residual stress distribution have been studied at welds in high strength 800 MPa steel. Effects of residual stress levels on fatigue life are also presented. Tensile loading was used to induce precisely controlled plastic deformation at weld toes. Residual stress distributions were measured by neutron diffraction. The influence of fatigue loading on the residual stress level was much smaller than that of plastic deformation. A large drop of residual stresses in the vicinity of the welds was recognised after local straining at the level of 2%. Stresses decreased with up to 550 MPa in the region around the weld toe. The effect of local plastic deformation on fatigue properties was also found to be significant. Fatigue strength more than doubled compared to the non-strained as-welded condition. Klíčová slova: neutron diffraction; residual stress Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Influence of Plastic Deformation on the Residual Stress Distribution and Fatigue Behaviour of High Strength Steels Welds

The effects of plastic deformation and cyclic loading on residual stress distribution have been studied at welds in high strength 800 MPa steel. Effects of residual stress levels on fatigue life are ...

Mráz, Ľ.; Karlsson, L.; Hamak, I.; Mikula, Pavol; Vrána, Miroslav
Ústav jaderné fyziky, 2010

Geometric Versus Spectral Convergence for the Neumann Laplacian under Exterior Perturbations of the Domain
Arrieta, J. M.; Krejčiřík, David
2010 - anglický This chapter is concerned with the behavior of the eigenvalues and eigenfunctions of the Laplace operator in bounded domains when the domain undergoes a perturbation. It is well known that if the boundary condition that we are imposing is of Dirichlet type, the kind of perturbations that we may allow in order to obtain the continuity of the spectra is much broader than in the case of a Neumann boundary condition. This is explicitly stated in the pioneer work of Courant and Hilbert [CoHi53], and it has been subsequently clarified in many works, see [BaVy65, Ar97, Da03] and the references therein among others. See also [HeA06] for a general text on different properties of eigenvalues and [HeD05] for a study on the behavior of eigenvalues and in general partial differential equations when the domain is perturbed. Klíčová slova: eigenvalues; Laplace operator; Dirichlet condition Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Geometric Versus Spectral Convergence for the Neumann Laplacian under Exterior Perturbations of the Domain

This chapter is concerned with the behavior of the eigenvalues and eigenfunctions of the Laplace operator in bounded domains when the domain undergoes a perturbation. It is well known that if the ...

Arrieta, J. M.; Krejčiřík, David
Ústav jaderné fyziky, 2010

Photo- and electro-production of kaons
Bydžovský, Petr
2010 - anglický Isobar models for the electromagnetic production of K+ and K-0 are discussed with emphasis on the K-0 photoproduction off neutron. Predictions of the models for the K-0 photoproduction on deuteron are compared with the recent data and some properties of the elementary amplitudes are shown. Klíčová slova: electromagnetic production; photoproduction; model Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Photo- and electro-production of kaons

Isobar models for the electromagnetic production of K+ and K-0 are discussed with emphasis on the K-0 photoproduction off neutron. Predictions of the models for the K-0 photoproduction on deuteron are ...

Bydžovský, Petr
Ústav jaderné fyziky, 2010

Sledování 14C v biotě a HTO ve vzdušné vlhkosti v okolí JE
Světlík, Ivo; Fejgl, M.; Michálek, V.; Tomášková, Lenka
2010 - český Klíčová slova: 14C; nuclear power plants; HTO Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Sledování 14C v biotě a HTO ve vzdušné vlhkosti v okolí JE

Světlík, Ivo; Fejgl, M.; Michálek, V.; Tomášková, Lenka
Ústav jaderné fyziky, 2010

Vybrané experimenty realizované v poslední době na mikrotronu MT25
Chvátil, David; Krist, Pavel
2010 - český V posledních několika letech prošel cyklický urychlovač elektronů MT25 zásadní modernizací všech napájecích zdrojů a HF systému. Tyto práce byly prováděny za účelem automatizovaného provozu urychlovače a možnosti jeho řízení průmyslovým počítačem. This article aims to provide readers with some interesting experiments carried out on microtron MT25 in last months.The cyclic electron accelerator- microtron MT25 is simply source of electron, photon and neutron beams with energy range from 6MeV to 25MeV. Klíčová slova: microtronMT25 Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Vybrané experimenty realizované v poslední době na mikrotronu MT25

V posledních několika letech prošel cyklický urychlovač elektronů MT25 zásadní modernizací všech napájecích zdrojů a HF systému. Tyto práce byly prováděny za účelem automatizovaného provozu ...

Chvátil, David; Krist, Pavel
Ústav jaderné fyziky, 2010

Tvorba kapalinového scintilačního impulsového spectra zářičů beta a projevy stěnového efektu
Šimek, Ondřej; Světlík, Ivo
2009 - český Klíčová slova: liquid scintilation pulse spectra; wall effect; MC simulation Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR. Tvorba kapalinového scintilačního impulsového spectra zářičů beta a projevy stěnového efektu

Šimek, Ondřej; Světlík, Ivo
Ústav jaderné fyziky, 2009