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

We report on the observation of a previously unknown resonance at ${E}_{R}^{\mathrm{lab}}=194.1\ifmmode\pm\else\textpm\fi{}0.6\text{ }\text{ }\mathrm{keV}$ in the $^{17}\mathrm{O}(p,\ensuremath{\alpha})^{14}\mathrm{N}$ reaction, with a measured resonance strength $\ensuremath{\omega}{\ensuremath{\gamma}}_{p\ensuremath{\alpha}}=1.6\ifmmode\pm\else\textpm\fi{}0.2\text{ }\text{ }\mathrm{meV}$. We studied in the same experiment the $^{17}\mathrm{O}(p,\ensuremath{\gamma})^{18}\mathrm{F}$ reaction by an activation method and the resonance-strength ratio was found to be $\ensuremath{\omega}{\ensuremath{\gamma}}_{p\ensuremath{\alpha}}/\ensuremath{\omega}{\ensuremath{\gamma}}_{p\ensuremath{\gamma}}=470\ifmmode\pm\else\textpm\fi{}50$. The corresponding excitation energy in the $^{18}\mathrm{F}$ compound nucleus was determined to be $5789.8\ifmmode\pm\else\textpm\fi{}0.3\text{ }\text{ }\mathrm{keV}$ by $\ensuremath{\gamma}$-ray measurements using the $^{14}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{18}\mathrm{F}$ reaction. These new resonance properties have important consequences for $^{17}\mathrm{O}$ nucleosynthesis and $\ensuremath{\gamma}$-ray astronomy of classical novae.