Freeze-in bino dark matter in high-scale supersymmetry

We explore a scenario of high-scale supersymmetry where all supersymmetric particles except gauginos stay at a high-energy scale <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msub><a:mi>M</a:mi><a:mi>SUSY</a:mi></a:msub></a:math> that is much larger than the reheating temperature <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:msub><c:mi>T</c:mi><c:mi>RH</c:mi></c:msub></c:math>. The dark matter is dominated by a bino component with mass around the electroweak scale and the observed relic abundance is mainly generated by the freeze-in process during the early Universe. Considering the various constraints, we identify two available scenarios in which the supersymmetric sector at an energy scale below <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:msub><e:mi>T</e:mi><e:mi>RH</e:mi></e:msub></e:math> consists of (a) bino or (b) bino and wino. Typically, for a bino mass around 0.1–1 TeV and a wino mass around 2 TeV, we find that <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:msub><g:mi>M</g:mi><g:mi>SUSY</g:mi></g:msub></g:math> should be around <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"><i:msup><i:mn>10</i:mn><i:mrow><i:mn>13</i:mn><i:mo>−</i:mo><i:mn>14</i:mn></i:mrow></i:msup><i:mtext> </i:mtext><i:mtext> </i:mtext><i:mi>GeV</i:mi></i:math> with <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"><k:msub><k:mi>T</k:mi><k:mi>RH</k:mi></k:msub></k:math> around <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:msup><m:mn>10</m:mn><m:mrow><m:mn>4</m:mn><m:mo>−</m:mo><m:mn>6</m:mn></m:mrow></m:msup><m:mtext> </m:mtext><m:mtext> </m:mtext><m:mi>GeV</m:mi></m:math>.