Leptogenesis during an era of early SU(2) confinement

We explore leptogenesis during a cosmological epoch during which the electroweak <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mrow><a:mi>SU</a:mi></a:mrow><a:mo stretchy="false">(</a:mo><a:mn>2</a:mn><a:msub><a:mrow><a:mo stretchy="false">)</a:mo></a:mrow><a:mrow><a:mi>L</a:mi></a:mrow></a:msub></a:mrow></a:math> force is confined. During weak confinement, there is only one conserved nonanomalous global charge, <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:mi>r</e:mi></e:math>, which is a linear combination of lepton-number, baryon-number, and hypercharge. The inclusion of heavy Majorana neutrinos leads to an <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:mi>r</g:mi></g:math>-charge and <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"><i:mi>C</i:mi><i:mi>P</i:mi></i:math>-violating interaction with a composite scalar, <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"><k:mi mathvariant="normal">Φ</k:mi></k:math>, and composite fermions, <n:math xmlns:n="http://www.w3.org/1998/Math/MathML" display="inline"><n:mi mathvariant="normal">Ψ</n:mi></n:math>, allowing for the generation of an <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"><q:mi>r</q:mi></q:math>-charge asymmetry, which translates into a baryon asymmetry post <s:math xmlns:s="http://www.w3.org/1998/Math/MathML" display="inline"><s:mrow><s:mi>SU</s:mi></s:mrow><s:mo stretchy="false">(</s:mo><s:mn>2</s:mn><s:msub><s:mo stretchy="false">)</s:mo><s:mi>L</s:mi></s:msub></s:math> deconfinement. Determining the resulting baryon asymmetry as a function of the model parameters, we find that the predicted baryon-asymmetry can match observations for a wide swath of parameter space: a weak confinement scale <w:math xmlns:w="http://www.w3.org/1998/Math/MathML" display="inline"><w:msub><w:mi mathvariant="normal">Λ</w:mi><w:mi>W</w:mi></w:msub><w:mo>∼</w:mo><w:msup><w:mn>10</w:mn><w:mn>11</w:mn></w:msup><w:mi>–</w:mi><w:msup><w:mn>10</w:mn><w:mn>14</w:mn></w:msup><w:mtext> </w:mtext><w:mtext> </w:mtext><w:mi>GeV</w:mi></w:math>, the sum of the Standard Model Yukawa couplings <z:math xmlns:z="http://www.w3.org/1998/Math/MathML" display="inline"><z:mo>∑</z:mo><z:msub><z:mi>Y</z:mi><z:mrow><z:mi>i</z:mi><z:mi>α</z:mi></z:mrow></z:msub><z:msubsup><z:mi>Y</z:mi><z:mrow><z:mi>i</z:mi><z:mi>α</z:mi></z:mrow><z:mo>*</z:mo></z:msubsup><z:mo>∼</z:mo><z:msup><z:mn>10</z:mn><z:mrow><z:mo>−</z:mo><z:mn>2</z:mn></z:mrow></z:msup><z:mo>−</z:mo><z:msup><z:mn>10</z:mn><z:mn>0</z:mn></z:msup></z:math>, <bb:math xmlns:bb="http://www.w3.org/1998/Math/MathML" display="inline"><bb:msub><bb:mi>m</bb:mi><bb:mi mathvariant="normal">Φ</bb:mi></bb:msub><bb:mo>/</bb:mo><bb:msub><bb:mi>m</bb:mi><bb:mi mathvariant="normal">Ψ</bb:mi></bb:msub><bb:mo>∼</bb:mo><bb:mn>0</bb:mn><bb:mo>−</bb:mo><bb:mn>0.5</bb:mn></bb:math>, and a <fb:math xmlns:fb="http://www.w3.org/1998/Math/MathML" display="inline"><fb:mi mathvariant="normal">Φ</fb:mi><fb:mo>−</fb:mo><fb:mi mathvariant="normal">Ψ</fb:mi><fb:mo>−</fb:mo><fb:mi mathvariant="normal">Ψ</fb:mi></fb:math> coupling <kb:math xmlns:kb="http://www.w3.org/1998/Math/MathML" display="inline"><kb:mo stretchy="false">|</kb:mo><kb:mi>g</kb:mi><kb:mo stretchy="false">|</kb:mo><kb:mo>∼</kb:mo><kb:mn>1</kb:mn></kb:math> with complex phase <ob:math xmlns:ob="http://www.w3.org/1998/Math/MathML" display="inline"><ob:msub><ob:mi>θ</ob:mi><ob:mi>g</ob:mi></ob:msub><ob:mo>∼</ob:mo><ob:mi>π</ob:mi><ob:mo>/</ob:mo><ob:mn>4</ob:mn></ob:math>. While leptogenesis under the assumption of a standard cosmology relies on the complex phase of the neutrino Yukawa couplings, the asymmetry generated in this novel background cosmology primarily depends on a strong phase from <qb:math xmlns:qb="http://www.w3.org/1998/Math/MathML" display="inline"><qb:mrow><qb:mi>SU</qb:mi></qb:mrow><qb:mo stretchy="false">(</qb:mo><qb:mn>2</qb:mn><qb:msub><qb:mo stretchy="false">)</qb:mo><qb:mi>L</qb:mi></qb:msub></qb:math> confinement, <ub:math xmlns:ub="http://www.w3.org/1998/Math/MathML" display="inline"><ub:msub><ub:mi>θ</ub:mi><ub:mi>g</ub:mi></ub:msub></ub:math>, and favors negligible <wb:math xmlns:wb="http://www.w3.org/1998/Math/MathML" display="inline"><wb:mi>C</wb:mi><wb:mi>P</wb:mi></wb:math>-violation in the right-handed neutrino decays.