Explosive Hydrogen Burning of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mmultiscripts><mml:mi mathvariant="normal">O</mml:mi><mml:mprescripts /><mml:none /><mml:mn>17</mml:mn></mml:mmultiscripts></mml:math>in Classical Novae

Fox, C.; Iliadis, Christian; Champagne, Arthur E; Coc, A.; José, J.; Longland, R.; Newton, Joseph; Pollanen, J.; Runkle, Robert C.

doi:10.1103/physrevlett.93.081102

Cited by 40 publications

(44 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At these conditions hydrogen burning reaches peak temperatures around T= 0.1 − 0.4 GK [7]. In this scenario, 17 O(p, γ) 18 F directly affects the production of the β + unstable 18 F (t 1/2 = 110 min) [8,9], whose 511 keV electron-positron annihilation γ-ray could potentially be detected by γ-ray satellites, such as the INTEGRAL observatory [10].…”

Section: Introductionmentioning

confidence: 99%

Proton capture on17O and its astrophysical implications

et al. 2012

View full text Add to dashboard Cite

Background: The reaction17 O(p, γ) 18 F influences hydrogen-burning nucleosynthesis in several stellar sites, such as red giants, asymptotic giant branch (AGB) stars, massive stars and classical novae. In the relevant temperature range for these environments (T9 = 0.01-0.4), the main contributions to the rate of this reaction are the direct capture process, two low lying narrow resonances (Er = 65.1 and 183 keV) and the low-energy tails of two broad resonances (Er = 557 and 677 keV).Purpose: Previous measurements and calculations give contradictory results for the direct capture contribution which in turn increases the uncertainty of the reaction rate. In addition, very few published cross section data exist for the high energy region that might affect the interpretation of the direct capture and the contributions of the broad resonances in the lower energy range. This work aims to address these issues.Method: The reaction cross section was measured in a wide proton energy range (Ec.m. = 345 -1700 keV) and at several angles (θ lab = 0• , 45The observed primary γ-transitions were used as input in an R-matrix code in order to obtain the contribution of the direct capture and the two broad resonances to the low-energy region.Results: The extrapolated S-factor from the present data is in good agreement with the existing literature data in the low-energy region. A new reaction rate was calculated from the combined results of this work and literature S-factor determinations. Resonance strengths and branchings are reported for several 18 F states. Conclusions:We were able to extrapolate the astrophysical S-factor of the reaction 17 O(p, γ) 18 F at low energies from cross section data taken at higher energies. No significant changes in the nucleosynthesis are expected from the newly calculated reaction rate.

show abstract

Section: Introductionmentioning

confidence: 99%

Proton capture on17O and its astrophysical implications

et al. 2012

View full text Add to dashboard Cite

show abstract

“…1 However, Rolfs's lowest energy points display a very different energy dependence compared to subsequent studies, so Fox et al [15] questioned whether those data points were dominated by the DC process or rather affected by the presence of the two broad resonance tails.…”

Section: Introductionmentioning

confidence: 98%

“…During the thermonuclear runaway that powers the nova phenomenon, the 17 O(p,γ ) 18 F reaction competes with the faster 17 O(p,α) 14 N. The 17 O(p,γ ) 18 F reaction leads to the production of 18 F and of 18 O through its subsequent β + decay (t 1/2 = 109.77 min [6]) and contributes to the synthesis of 19 F and 15 N, through the 18 O(p,γ ) 19 F and 18 O(p,α) 15 N reactions, respectively [2,5].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Underground study of theO17(p,γ)F18reaction relevant for explosive hydrogen burning

et al. 2014

Self Cite

View full text Add to dashboard Cite

Background:The 17 O(p,γ ) 18 F reaction affects the production of key isotopes (e.g., 18 F and 18 O) in the explosive hydrogen burning that powers classical novae. Under these explosive conditions, the reaction rate is dominated by contributions from a narrow resonance at E c.m. = 183 keV and by the combined contributions of direct capture and low-energy tails of broad resonances. At present, the astrophysical reaction rate is not well constrained because of the lack of data in the energy region appropriate to classical novae. Purpose: This study aims at the measurement of the 17 O(p,γ ) 18 F reaction cross section in order to determine its reaction rate in the temperature region appropriate to explosive hydrogen burning in novae. Method: The 17 O(p,γ ) 18 F reaction cross section was measured using both the prompt detection of the emitted γ rays and an activation technique. Measurements were carried out at the Laboratory for Underground Nuclear Astrophysics (Gran Sasso, Italy) where the strongly reduced cosmic-ray-induced background allows for improved sensitivity compared to previous studies. Results: The 17 O(p,γ ) 18 F reaction cross section was measured in the range E c.m. = 160 to 370 keV. The strength of the E c.m. = 183 keV resonance, ωγ = 1.67 ± 0.12 μeV, was determined with unprecedented precision. The total S factor was obtained through a combined fit of prompt γ -ray and activation results. An overall global fit including other existing data sets was also carried out and a recommended astrophysical reaction rate is presented. Conclusions:The reaction rate uncertainty attained in this work is now below the required precision for nova models. We verified, following a full set of hydrodynamic nova models, that the abundances of oxygen and fluorine isotopes obtained with the present reaction rate are determined with 10% precision and put firmer constraints on observational signatures of novae events.

show abstract

“…After the turn of the century, several experimental studies were carried out, mostly concentrating on the low energy region below about 500 keV [4,[6][7][8][9][10][11][12][13][14]. (The only exception was the work of Kontos et al [11] which extended up to 1.6 MeV.)…”

Section: Introductionmentioning

confidence: 99%

Cross section measurement of the astrophysically important O17(p,γ)F18
Gyürky
¹
,
Ornelas
²
,
Fülöp
³

et al. 2017
Phys. Rev. C
11
0
6
0
View full text Add to dashboard Cite

Background:The 17 O(p,γ ) 18 F reaction plays an important role in hydrogen burning processes in several different stages of stellar evolution. The rate of this reaction must therefore be known with high accuracy at the relevant temperatures in order to provide the necessary input for astrophysical models. Purpose: The cross section of 17 O(p,γ ) 18 F is characterized by a complicated resonance structure at low energies which needs to be reproduced by theoretical models if a reliable extrapolation to astrophysical energies is required. Experimental data, however, are scarce in a wide energy range, which increases the uncertainty of the extrapolations. The purpose of the present work is therefore to provide consistent and precise cross section values in a wide energy range for the 17 O(p,γ ) 18 F reaction. Method: The cross section is measured using the activation method. This method provides directly the total cross section which can be compared with model calculations. With this technique some typical systematic uncertainties encountered in in-beam γ -spectroscopy experiments can be avoided. Results: The cross section was measured between 500 keV and 1.8 MeV proton energies with a total uncertainty of typically 10%. The results are compared with earlier measurements and it is found that the gross features of the 17 O(p,γ ) 18 F excitation function are relatively well reproduced by the present data. Deviation of roughly a factor of 1.5 is found in the case of the total cross section when compared with the only high energy dataset. At the lowest measured energy our result is in agreement with two recent datasets within one standard deviation and deviates by roughly two standard deviations from a third one. An R-matrix analysis of the present and previous data strengthens the reliability of the extrapolated zero energy astrophysical S factor. Conclusions: Using an independent experimental technique, the literature cross section data of 17 O(p,γ ) 18 F is confirmed in the energy region of the resonances while a lower direct capture cross section is recommended at higher energies. The present dataset provides a constraint for the theoretical cross sections.

show abstract

Explosive Hydrogen Burning ofO17in Classical Novae

Cited by 40 publications

References 15 publications

Proton capture on17O and its astrophysical implications

Proton capture on17O and its astrophysical implications

Underground study of theO17(p,γ)F18reaction relevant for explosive hydrogen burning

Cross section measurement of the astrophysically important O17(p,γ)F18
Gyürky
¹
,
Ornelas
²
,
Fülöp
³

et al. 2017
Phys. Rev. C
11
0
6
0
View full text Add to dashboard Cite

Contact Info

Product

Resources

About

Explosive Hydrogen Burning ofO17in Classical Novae

Cited by 40 publications

References 15 publications

Proton capture on17O and its astrophysical implications

Proton capture on17O and its astrophysical implications

Underground study of theO17(p,γ)F18reaction relevant for explosive hydrogen burning

Cross section measurement of the astrophysically important O17(p,γ)F18Gyürky1, Ornelas2, Fülöp3 et al. 2017Phys. Rev. C11060View full textAdd to dashboardCite

Contact Info

Product

Resources

About

Cross section measurement of the astrophysically important O17(p,γ)F18
Gyürky
¹
,
Ornelas
²
,
Fülöp
³

et al. 2017
Phys. Rev. C
11
0
6
0
View full text Add to dashboard Cite