Underground experimental study finds no evidence of low-energy resonance in the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mmultiscripts><mml:mi>Li</mml:mi><mml:mprescripts/><mml:none/><mml:mn>6</mml:mn></mml:mmultiscripts><mml:mo>(</mml:mo><mml:mi>p</mml:mi><mml:mo>,</mml:mo><mml:mi>γ</mml:mi><mml:mo>)</mml:mo><mml:mmultiscripts><mml:mi>Be</mml:mi><mml:mprescripts/><mml:none/><mml:mn>7</mml:mn></mml:mmultiscripts></mml:mrow></mml:math>reaction

The astrophysical $^{6}\mathrm{Li}(p,\ensuremath{\gamma})^{7}\mathrm{Be}$ reaction occurs during Big Bang nucleosynthesis and the pre-main sequence and main sequence phases of stellar evolution. The low-energy trend of its cross section remains uncertain, since different measurements have provided conflicting results. A recent experiment reported a resonancelike structure at center-of-mass energy 195 keV, associated to a positive-parity state of $^{7}\mathrm{Be}$. The existence of such resonance is still a matter of debate. We report a new measurement of the $^{6}\mathrm{Li}(p,\ensuremath{\gamma})^{7}\mathrm{Be}$ cross section performed at the Laboratory for Underground Nuclear Astrophysics, covering the center-of-mass energy range $E=60$--350 keV. Our results rule out the existence of low-energy resonances. The astrophysical $S$-factor varies smoothly with energy, in agreement with theoretical models.

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