Note on stellar26Al production via the25Mg(p, ?) process

Bergmeister, F.J.; Lieb, Klaus‐Peter; Pampus, K.; Uhrmacher, M.

doi:10.1007/bf01411874

Cited by 13 publications

(6 citation statements)

References 8 publications

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“…The resonance widths and strengths for the 25 Mg(p, γ) 26 Al reaction have been studied directly using a low-energy proton beam and 25 Mg target, for example in [202][203][204][205]. In addition, spectroscopic factors for proton-unbound levels in 26 Al and their influence on stellar reaction rates have been investigated, e.g.…”

Section: E X (Kev)mentioning

confidence: 99%

Progress on nuclear reaction rates affecting the stellar production of ²⁶Al

Laird

Lugaro

Kankainen

et al. 2023

J. Phys. G: Nucl. Part. Phys.

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The radioisotope 26Al is a key observable for nucleosynthesis in the Galaxy and the environment of the early Solar System. To properly interpret the large variety of astronomical and meteoritic data, it is crucial to understand both the nuclear reactions involved in the production of 26Al in the relevant stellar sites and the physics of such sites. These range from the winds of low- and intermediate-mass asymptotic giant branch (AGB) stars; to massive and very massive stars, both their Wolf-Rayet (WR) winds and their final core-collapse supernovae (CCSN); and the ejecta from novae, the explosions that occur on the surface of a white dwarf accreting material from a stellar companion. Several reactions affect the production of 26Al in these astrophysical objects, including (but not limited to) 25Mg(p,γ)26Al, 26Al(p,γ)27Si, and 26Al(n,p/α). Extensive experimental effort has been spent during recent years to improve our understanding of such key reactions. Here we present a summary of the astrophysical motivation for the study of 26Al, a review of its production in the different stellar sites, and a timely evaluation of the currently available nuclear data. We also provide recommendations for the nuclear input into stellar models and suggest relevant, future experimental work.

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Section: E X (Kev)mentioning

confidence: 99%

Progress on nuclear reaction rates affecting the stellar production of ²⁶Al

Laird

Lugaro

Kankainen

et al. 2023

J. Phys. G: Nucl. Part. Phys.

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“…42. Gamma-ray yield curve of the reaction 24 Mg(p,y) 26 Al at the 389 keV resonance [215]. The solid lines correspond to the resonance widths Γ= 0 (a), Γ= 2eV (b), and Γ = 4eV (c).…”

Section: Determination Of Narrow Resonance Widthsmentioning

confidence: 99%

“…41 shows the total beam spread Wt)iv = (w?v + WD 2 ) 1/2 of the Göttingen 530 kV IONAS accelerator and the two contributions WTip and WD at room temperature [210], The measured beam spread at the various resonances on 23 shows the γ-ray excitation function of the 25 Mg(p,y) 26 Al 389 keV resonance [215]. The low-energy tail of the resonance is sensitive to whether the count rate is a consequence of the beam straggling (integrated error function) or the finite resonance width /"(arctan yield curve).…”

Section: Determination Of Narrow Resonance Widthsmentioning

confidence: 99%

12 The Measurement of Nuclear Lifetimes

1997

Experimental Techniques in Nuclear Physics

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Table of Contents I. Scope and definitions 425 II. Decay constants of "rare" decays 427 A. Very long lifetimes 427 B. Very small activities 428 C. Precision studies of the neutron lifetime 434 III. Direct timing methods (10~6 > τ > 10" 15 s) 437 A. Electronic and pulsed beam timing methods 437 B. Recoil shadow timing methods 445 C. The recoil distance "plunger" method 447 D. The Doppler shift attenuation method 453 E. The GRID method 466 IV. Measurement of very short lifetimes (τ < 10" 15 s) 472 A. X-ray timing 473 B. Crystal blocking 474 C. Nuclear resonance fluorescence 475 D. Determination of narrow resonance widths 478 References 482 I. Scope and definitionsThe decay modes of ground states and the low-lying nuclear states up to about 10 MeV excitation energy via ß-decay, electromagnetic radiations, particle emission and/or fission have been extensively studied for many decades. In all domains of nuclear structure investigations, the measurement of absolute decay probabilities and nuclear lifetimes has given important insight into the facets of nuclear many-body systems and has provided detailed data for in-depth tests of nuclear models. Some of these decay modes involve fundamentally known interactions, e.g. the electro-weak interaction in the case of β-and γ-decay processes, and thus are directly sensitive to the nuclear model wave functions to be tested. Other processes like nucleon emission, α-decay and fission are more difficult to deal with theoretically, as here the wave functions of the nuclear states involved in the transition and the nuclear transition operator, which both determine the decay probabilities, depend on the model used.The experimentally accessible range of nuclear lifetimes covers more than forty-five (!) orders of magnitude. When just considering α-decays, we have, on the one hand, the Unauthenticated Download Date | 6/13/16 9:10 AM

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“…5(a). Two independent measurements of the reaction 25 Mg(p,γ) 26 Al [32,33] have the highest impact on the final AME 2003 mass. In addition, Q-values of the reactions 26 Mg(p, n) 26 Al [34], 26 Mg( 3 He, t) 26 Al-14 N( 3 He, t) 14 O [35], and 42 Ca( 3 He, t) 42 Sc-26 Mg( 3 He, t) 26 Al [35] contribute to the mass of 26 Al.…”

Section: The Cyclotronmentioning

confidence: 99%

“…7 (a). The highest impact on the final AME2003 mass have two independent measurements of the reaction 25 Mg(p,γ) 26 Al [35,36]. In addition Q-values of the reactions 26 Mg(p,n) 26 Al [37], 26 Mg( 3 He,t) 26 Al-14 N() 14 O [38], and 42 Ca( 3 He,t) 42 Sc-26 Mg() 26 Al [38] contribute to the mass of 26 Al.…”

mentioning

confidence: 99%

Time-separated oscillatory fields for high-precision mass measurements on short-lived Al and Ca nuclides

et al. 2008

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High-precision Penning trap mass measurements on the stable nuclide 27 Al as well as on the short-lived radionuclides 26 Al and 38,39 Ca have been performed by use of radiofrequency excitation with time-separated oscillatory fields, i.e. Ramsey's method, as recently introduced for the excitation of the ion motion in a Penning trap, was applied. A comparison with the conventional method of a single continuous excitation demonstrates its advantage of up to ten times shorter measurements. The new mass values of 26,27 Al clarify conflicting data in this specific mass region. In addition, the resulting mass values of the superallowed β-emitter 38 Ca as well as of the groundstate of the β-emitter 26 Al m confirm previous measurements and corresponding theoretical corrections of the f t-values.Introduction. -Superallowed 0 + → 0 + β-decays are sensitive probes for testing fundamental concepts of weak interaction. Hardy and Towner [1] addressed 20 such decays covering the nuclear chart from 10 C to 74 Rb and showed a consistent picture allowing a confirmation of the conserved-vector-current (CVC) hypothesis. Three properties of the nuclear transitions are merged in the comparative half-life f t : the transition energy Q EC , the half-life of the mother nuclei t 1/2 , and the branching ratio R. Since the Fermi-type β-decays are only effected by the vector part of the hadronic weak interaction, the CVC hypothesis claims identical f t -values for all transitions between

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Note on stellar26Al production via the25Mg(p, ?) process

Abstract: (1), used in the interpretation of stellar 26AI production was shown to be incorrect and probably caused by target oxidation effects and insufficient energy resolution of the beam. The new value is F<4 eV.

Cited by 13 publications

References 8 publications

Progress on nuclear reaction rates affecting the stellar production of ²⁶Al

Progress on nuclear reaction rates affecting the stellar production of ²⁶Al

12 The Measurement of Nuclear Lifetimes

Time-separated oscillatory fields for high-precision mass measurements on short-lived Al and Ca nuclides

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Note on stellar26Al production via the25Mg(p, ?) process

Abstract: (1), used in the interpretation of stellar 26AI production was shown to be incorrect and probably caused by target oxidation effects and insufficient energy resolution of the beam. The new value is F<4 eV.

Cited by 13 publications

References 8 publications

Progress on nuclear reaction rates affecting the stellar production of 26Al

Progress on nuclear reaction rates affecting the stellar production of 26Al

12 The Measurement of Nuclear Lifetimes

Time-separated oscillatory fields for high-precision mass measurements on short-lived Al and Ca nuclides

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Product

Resources

About

Progress on nuclear reaction rates affecting the stellar production of ²⁶Al

Progress on nuclear reaction rates affecting the stellar production of ²⁶Al