Radiative corrections to aid the direct detection of the Higgsino-like neutralino dark matter: Spin-independent interactions

The lightest neutralino (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msubsup><a:mover accent="true"><a:mi>χ</a:mi><a:mo stretchy="false">˜</a:mo></a:mover><a:mn>1</a:mn><a:mn>0</a:mn></a:msubsup></a:math>) is a good dark matter (DM) candidate in the <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mi>R</e:mi></e:math>-parity conserving minimal supersymmetric Standard Model. In this work, we consider the light Higgsino-like neutralino as the lightest stable particle, thanks to a rather small Higgsino mass parameter <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:mi>μ</g:mi></g:math>. We then estimate the prominent radiative corrections to the neutralino-neutralino-Higgs boson vertices. We show that for Higgsino-like <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"><i:msubsup><i:mover accent="true"><i:mi>χ</i:mi><i:mo stretchy="false">˜</i:mo></i:mover><i:mn>1</i:mn><i:mn>0</i:mn></i:msubsup></i:math>, these corrections can significantly influence the spin-independent direct detection cross section, even contributing close to 100% in certain regions of the parameter space. These corrections, therefore, play an important role in deducing constraints on the mass of the Higgsino-like lightest neutralino DM, and thus the <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:mi>μ</m:mi></m:math> parameter. Published by the American Physical Society 2024