The History and Impact of the CNO Cycles in Nuclear Astrophysics

Wiescher, M.

doi:10.1007/s00016-018-0216-0

Cited by 11 publications

(9 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This value still differs from the present one by about two standard deviations. 1 Consequently, as opposed to the E p = 278 keV resonance, this strength value is rather uncertain and further measurements would be required. 1 The subtraction of the non-resonant component in Ref.…”

Section: Results and Conclusionmentioning

confidence: 99%

“…1 Consequently, as opposed to the E p = 278 keV resonance, this strength value is rather uncertain and further measurements would be required. 1 The subtraction of the non-resonant component in Ref. [19] may also be overestimated.…”

Section: Results and Conclusionmentioning

confidence: 99%

“…Catalytic cycles of hydrogen burning represent an alternative way to the pp chains for converting four protons into one α particle in stellar interiors and for providing thus the energy source of stars. The simplest cycle is the first CNO or Bethe-Weizsäcker cycle [1] where carbon, nitrogen, and oxygen isotopes are involved. The CNO cycle is the dominant energy source of main sequence stars more massive than about 1.3 solar masses but it also plays an important role in various astrophysical scenarios including quiescent and explosive burning processes (e.g., Refs.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Resonance strengths in the N14 ( p,γ)O15
Gyürky
¹
,
Halász
²
,
Kiss
³

et al. 2019
Phys. Rev. C
14
0
11
0
View full text Add to dashboard Cite

Background: The 14 N(p, γ) 15 O reaction plays a vital role in various astrophysical scenarios. Its reaction rate must be accurately known in the present era of high precision astrophysics. The cross section of the reaction is often measured relative to a low energy resonance, the strength of which must therefore be determined precisely. Purpose: The activation method, based on the measurement of 15 O decay, has not been used in modern measurements of the 14 N(p, γ) 15 O reaction. The aim of the present work is to provide strength data for two resonances in the 14 N(p, γ) 15 O reaction using the activation method. The obtained values are largely independent from previous data measured by in-beam γ spectroscopy and are free from some of their systematic uncertainties. Method: Solid state TiN targets were irradiated with a proton beam provided by the Tandetron accelerator of Atomki using a cyclic activation. The decay of the produced 15 O isotopes was measured by detecting the 511 keV positron annihilation γ rays. Results: The strength of the E p = 278 keV resonance was measured to be ωγ 278 = (13.4 ± 0.8) meV while for the E p = 1058 keV resonance ωγ 1058 = (442 ± 27) meV. Conclusions: The obtained E p = 278 keV resonance strength is in fair agreement with the values recommended by two recent works. However, the E p = 1058 keV resonance strength is about 20% higher than the previous value. The discrepancy may be caused in part by a previously neglected finite target thickness correction. As only the low energy resonance is used as a normalization point for cross section measurements, the calculated astrophysical reaction rate of the 14 N(p, γ) 15 O reaction and therefore the astrophysical consequences are not changed by the present results.

show abstract

Section: Results and Conclusionmentioning

confidence: 99%

Section: Results and Conclusionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Resonance strengths in the N14 ( p,γ)O15
Gyürky
¹
,
Halász
²
,
Kiss
³

et al. 2019
Phys. Rev. C
14
0
11
0
View full text Add to dashboard Cite

show abstract

“…Their correct interpretation is inevitable and it will definitely lead to the developed ideas. 1,2,3,12…”

Section: Discussionmentioning

confidence: 99%

The Implementation of the Alternative Fusion Reactor Project

Fisenko

2022

Orient J Phys Sciences

View full text Add to dashboard Cite

As it is known, the main efforts of the international community to solve the problem of controlled thermonuclear fusion are concentrated mainly on the International Thermonuclear Experimental Reactor (ITER) project. The achievement of positive results in this project is still very problematic. Experimental data show the absence of plasma retention in a stable state. The effectiveness of the magnetic field is limited only by heating the plasma, but not by its retention in a stable state, and at the moment it is an indisputable experimental fact.

show abstract

“…Hydrogen burning is perhaps the most important source of energy in our universe as all stars start their lives by fusing hydrogen into helium [1]. Stars less massive than about 1.3 solar masses burn hydrogen dominantly through the pp-chain reactions, while more massive stars utilize the CNO cycle, a catalytic cycle of reactions on C, N and O isotopes [2]. Our Sun belongs to the first group, roughly 98 % of its energy is thus generated by the pp-chains.…”

mentioning

confidence: 99%

Activation cross section measurement of the 14N(p,gamma)15O astrophysical key reaction

Gyürky,

Halász,

Kiss

et al. 2022

Preprint

View full text Add to dashboard Cite

Background 14 N(p,γ) 15 O is one of the key reactions of nuclear astrophysics playing a role in various stellar processes and influencing energy generation of stars, stellar evolution and nucleosynthesis. For a reliable reaction rate calculation the low energy cross section of 14 N(p,γ) 15 O must be known with high accuracy. Owing to the unmeasurable low cross sections, theoretical calculations are unavoidable.Purpose High precision experimental cross section data are needed in a wide energy range in order to provide the necessary basis for low energy extrapolations. In the present work the total 14 N(p,γ) 15 O cross section was measured with a method complementary to the available data sets.Method The cross section was measured with activation, based on the detection of the annihilation radiation following the β + -decay of the reaction product 15 O. This method, which provides directly the astrophysically important total cross section, was never used for the 14 N(p,γ) 15 O cross section measurement in the studied energy range. ResultsThe non-resonant cross section was measured between 550 keV and 1400 keV center-of-mass energies with total uncertainty of about 10 %. The results were compared with literature data using an R-matrix analysis. It is found that the cross sections measured in this work are in acceptable agreement with the two recent measurements only if the weak transitions -not measured in those works -are included. ConclusionsThe present data set, being largely independent from the other available data, can be used to constrain the extrapolated cross sections to astrophysical energies and helps to make the astrophysical model calculations more reliable.

show abstract

The History and Impact of the CNO Cycles in Nuclear Astrophysics

Cited by 11 publications

References 52 publications

Resonance strengths in the N14 ( p,γ)O15
Gyürky
¹
,
Halász
²
,
Kiss
³

et al. 2019
Phys. Rev. C
14
0
11
0
View full text Add to dashboard Cite

Resonance strengths in the N14 ( p,γ)O15
Gyürky
¹
,
Halász
²
,
Kiss
³

et al. 2019
Phys. Rev. C
14
0
11
0
View full text Add to dashboard Cite

The Implementation of the Alternative Fusion Reactor Project

Activation cross section measurement of the 14N(p,gamma)15O astrophysical key reaction

Contact Info

Product

Resources

About

The History and Impact of the CNO Cycles in Nuclear Astrophysics

Cited by 11 publications

References 52 publications

Resonance strengths in the N14 ( p,γ)O15Gyürky1, Halász2, Kiss3 et al. 2019Phys. Rev. C140110View full textAdd to dashboardCite

Resonance strengths in the N14 ( p,γ)O15Gyürky1, Halász2, Kiss3 et al. 2019Phys. Rev. C140110View full textAdd to dashboardCite

The Implementation of the Alternative Fusion Reactor Project

Activation cross section measurement of the 14N(p,gamma)15O astrophysical key reaction

Contact Info

Product

Resources

About

Resonance strengths in the N14 ( p,γ)O15
Gyürky
¹
,
Halász
²
,
Kiss
³

et al. 2019
Phys. Rev. C
14
0
11
0
View full text Add to dashboard Cite

Resonance strengths in the N14 ( p,γ)O15
Gyürky
¹
,
Halász
²
,
Kiss
³

et al. 2019
Phys. Rev. C
14
0
11
0
View full text Add to dashboard Cite