36 research outputs found
Nuclear astrophysics with radioactive ions at FAIR
The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process, β-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes
Shapes of Pb 192,190 ground states from β -decay studies using the total-absorption technique
The beta decay of 192,190Pb has been studied using the total absorption technique at the ISOLDE(CERN) facility. The beta-decay strength deduced from the measurements, combined with QRPA theoretical calculations, allow us to infer that the ground states of the 192,190Pb isotopes are spherical. These results represent the first application of the shape determination method using the total absorption technique for heavy nuclei and in a region where there is considerable interest in nuclear shapes and shape effects
A nagyon idős és esendő állapotú betegek antihipertenzív kezelési gyakorlata az alapellátásban
Vérnyomáscsökkentés nagyon idős és esendő állapotú betegeknél: az alapellátásbeli gyakorlat kérdései = Variation in GP decisions on antihypertensive treatment
A vérnyomáscsökkentő terápiában a családorvosi gyakorlatban megmutatkozó eltérések elemzése érdekében 2543 családorvos bevonásával
online kérdőíves felmérést végeztünk különböző karakterisztikájú – esendőség, SBP
és CVD tekintetében –, nagyon idős (80 évesnél idősebb) betegek körében. Arra
is kerestük a választ, hogy mennyire befolyásolja a kezelési döntésüket az időskori esendőség. A tanulmányunk másik célkitűzése a magyar eredmények összehasonlítása volt a nemzetközi eredményekkel. Országonként összehasonlításra került
azon esetek aránya, amelyekben a kezelés mellett döntöttek a családorvosok. A
29 országból 24 országban (83%) a beteg esendő állapotát a családorvosok azzal
a döntéssel kapcsolták össze, hogy inkább nem indítanak kezelést. A legalacsonyabb kezelési arány Hollandiában volt, a legmagasabb arány pedig Ukrajnában.
Magyarország azon országok közé tartozott, ahol a családorvosok inkább kezelik
az esendő pácienseket (a kezelési arány 50–59% között volt). A páciens esendősége
nem befolyásolta a terápia megkezdését, sokkal jobban a cardiovascularis megbetegedés és a 160 Hgmm feletti SBP. A vizsgálat fontos üzenete volt, hogy továbbra
is szükséges a családorvosok és a családorvos-rezidensek oktatása az idős, esendő
hypertoniás betegek kezelésével kapcsolatban. = We conducted an online questionnaire survey with 2543 family
physicians to analyse the variation in antihypertensive therapy among very
elderly primary care patients (over 80 years of age) with different characteristics
in terms of prevalence, SBP and CVD. We also sought answers to our question of
how much their treatment decisions are influenced by their elderly frailty. Another
aim of our study was to compare Hungarian results with international results. We
compared the proportion of cases in which family doctors decided in favour of
treatment across countries. In 24 of the 29 countries (83%), family physicians
associated the patient's frailty with the decision not to initiate treatment. The
lowest treatment rate was in the Netherlands and the highest rate in Ukraine.
Hungary was one of the countries where family physicians preferred to treat
patients with frailty (treatment rates ranged from 50-59%). Patient’s frailty did
not influence the initiation of therapy, cardiovascular disease and SBP above 160
mmHg were more important. The main message from the study was the need for
continued education of family physicians and family medicine residents on the
management of elderly, frail hypertensive patients
Beeta-decay data requirements for reactor decay heat calculations: study of the possible source of the gamma-ray discrepancy in reactor heat summation calculations
High-resolution study of Tz=+2→+1 Gamow-Teller transitions in the 44Ca(3He,t)44Sc reaction
In order to study the Gamow-Teller (GT) transitions from the Tz=+2 nucleus 44Ca to the Tz=+1 nucleus 44Sc, where Tz is the z component of isospin T, we performed the (p,n)-type (3He,t) charge-exchange (CE) reaction at 140 MeV/nucleon and the scattering angles 0∘ and 2.5∘. An energy resolution of 28 keV, that was realized by applying matching techniques to the magnetic spectrometer system, allowed the study of fragmented states. The GT transition strengths, B(GT), were derived up to the excitation energy (Ex) of 13.7 MeV assuming the proportionality between cross sections and B(GT) values. The total sum of B(GT) values in discrete states was 3.7, which was 31% of the sum-rule-limit value of 12. Shell model calculations using the GXPF1J interaction could reproduce the gross features of the experimental B(GT) distribution, but not the fragmentation of the strength. By introducing the concepts of isospin, properties of isospin analogous transitions and states were investigated. (i) Assuming isospin symmetry, the Tz=+2→+1 and Tz=-2→-1 mirror GT transitions should have the same properties, where the latter can be studied in the β decay of 44Cr to 44V. First, we confirmed that the β-decay half-life T1/2 of 44Cr can be reproduced using the B(GT) distribution from the 44Ca(3He,t) measurement. Then, the 0∘, (3He,t) spectrum was modified to deduce the "β-decay spectrum" and it was compared with the delayed-proton spectrum from the 44Cr β decay. The two spectra were mostly in agreement for the GT excitations, but suppression of the proton decay was found for the T=2 isobaric analog state (IAS). (ii) Starting from the T=2 ground state of 44Ca, the (3He,t) can excite GT states (state populated by GT transitions) with T=1, 2, and 3. On the other hand, the 44Ca(p,p') reaction can excite spin-M1 states (states populated by spin-M1 transitions) with T=2 and 3 that are analogous to the T=2 and 3 GT states, respectively. By comparing the spectra from these two reactions, a T value of 2 is suggested for several GT states in the Ex=11.5-13.7 MeV region. (iii) It has been suggested that the T=2, Jπ=0+ double isobaric analog state (DIAS) at 9.338 MeV in the Tz=0 nucleus 44Ti forms an isospin-mixed doublet with a subsidiary 0+ state at 9.298 MeV. Since no corresponding state was found in the Tz=+1 nucleus 44Sc, we suggest T=0 for the subsidiary state