A bstract We discuss the effective field theory (EFT) for nuclear beta decay. The general quark-level EFT describing charged-current interactions between quarks and leptons is matched to nucleon-level non-relativistic at $$ \mathcal{O}\left(\textrm{MeV}\right) <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>O</mml:mi> <mml:mfenced> <mml:mi>MeV</mml:mi> </mml:mfenced> </mml:math> momentum scale characteristic transitions. matching takes into account, first time, effect of...

We present a systematic method for determining the two-loop effective Lagrangian resulting from integrating out set of heavy particles in an ultraviolet scalar theory. prove that matching coefficients are entirely determined (double-)hard region loop integrals and master formula matching, applicable to both diagrammatic functional approaches. further employ methods determine compact expressions do not rely on any previous knowledge its structure or symmetries. The same also computation...

The stability of the electroweak scale, challenged by absence deviations in flavor physics, prompts consideration SMEFT scenarios governed approximate SM symmetries. This study examines microscopic theories that match onto a set <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>U</a:mi><a:mo stretchy="false">(</a:mo><a:mn>3</a:mn><a:msup><a:mo stretchy="false">)</a:mo><a:mn>5</a:mn></a:msup></a:math>-symmetric dimension-6 operators. Renormalization group (RG) mixing...

We study the flavor structure of lepton and baryon number--conserving dimension-6 operators in Standard Model effective field theory (SMEFT). Building on work [1], we define several well-motivated symmetries symmetry-breaking patterns that serve as competing hypotheses about ultraviolet (UV) dynamics beyond SM, not far above TeV scale. In particular, consider four different structures quark sector seven charged sector. The set flavor-breaking spurions is (almost) always taken to be minimal...

A bstract Short-distance new physics at (or slightly) above the TeV scale should not excessively violate approximate flavor symmetries of SM in order to comply with stringent constraints from flavor-changing neutral currents. In this respect, provide an effective organizing principle for vast parameter space SMEFT. work, we classify all possible irreducible representations under U(3) 5 symmetry heavy spin-0, 1/2, and 1 fields which integrate out dimension-6 operators tree level. For a...

Given the absence of a definitive top-down indication for understanding peculiar structure lepton sector, discrete flavor symmetries offer profound perspective examining intricate patterns masses and mixings. In this work, drawing upon previous studies on interplay with potential UV completions from purely bottom-up perspective, three well-motivated groups, suitable portraying leptonic sector as well neutrino masses, specifically $A_4$, $A_5$ $S_4$, are explored within framework, leading to...

Given the absence of a definitive top-down indication for understanding peculiar structure lepton sector, discrete flavor symmetries offer profound perspective examining intricate patterns masses and mixings. In this work, drawing upon previous studies on interplay with potential UV completions from purely bottom-up perspective, three well-motivated groups, suitable portraying leptonic sector as well neutrino masses, specifically <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"...

Functional methods can be applied to the quantum effective action efficiently determine counterterms and matching conditions for field theories. We extend toolbox two-loop order beyond show how evaluate expansion of path integral in a manifestly gauge-covariant manner. also generalize method theories with mixed spin statistics prove validity hard-region formula all loop orders. The are exemplified calculation Euler-Heisenberg Lagrangian resulting from decoupling electron QED.

Short-distance new physics at (or slightly) above the TeV scale should not excessively violate approximate flavor symmetries of SM in order to comply with stringent constraints from flavor-changing neutral currents. In this respect, provide an effective organizing principle for vast parameter space SMEFT. work, we classify all possible irreducible representations under $U(3)^5$ symmetry heavy spin-0, 1/2, and 1 fields which integrate out dimension-6 operators tree level. For a general...

We present a systematic method for determining the two-loop effective Lagrangian resulting from integrating out set of heavy particles in an ultraviolet scalar theory. prove that matching coefficients are entirely determined (double-)hard region loop integrals and master formula matching, applicable to both diagrammatic functional approaches. further employ methods determine compact expressions do not rely on any previous knowledge its structure or symmetries. The same also computation...

The stability of the electroweak scale, challenged by absence deviations in flavor physics, prompts consideration SMEFT scenarios governed approximate SM symmetries. This study examines microscopic theories that match onto a set $U(3)^5$-symmetric dimension-6 operators. Renormalization group mixing from ultraviolet to scale yields significant phenomenological constraints, particularly pronounced for UV-motivated directions. To demonstrate this, we explore complete suite tree-level models...

We study the flavor structure of lepton and baryon number--conserving dimension-6 operators in Standard Model effective field theory (SMEFT). Building on work [1], we define several well-motivated symmetries symmetry-breaking patterns that serve as competing hypotheses about ultraviolet (UV) dynamics beyond SM, not far above TeV scale. In particular, consider four different structures quark sector seven charged sector. The set flavor-breaking spurions is (almost) always taken to be minimal...