Constraining νSMEFT coefficients: The case of the extra U(1)′

We study the constraints on low-energy coefficients of the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>ν</a:mi><a:mi>SMEFT</a:mi></a:math> generalization of the Standard Model effective theory in the simple case of a <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mi mathvariant="normal">U</c:mi><c:mo stretchy="false">(</c:mo><c:mn>1</c:mn><c:msup><c:mo stretchy="false">)</c:mo><c:mo>′</c:mo></c:msup></c:math> enlargement of the Standard Model gauge group. In particular, we analyze the constraints imposed by the requirement that the extended theory remains free of gauge anomalies. We present the cases of explicit realizations, showing the obtained correlations among the coefficients of <h:math xmlns:h="http://www.w3.org/1998/Math/MathML" display="inline"><h:mi>d</h:mi><h:mo>=</h:mo><h:mn>6</h:mn></h:math> operators.