Renato Higa

Electric Dipole Moments of Light Nuclei From Chiral Effective Field Theory

Recent calculations of EDMs of light nuclei in the framework of chiral effective field theory are presented. We argue that they can be written in terms of the leading six low-energy constants encoding CP-violating physics. EDMs of the deuteron, triton, and helion are explicitly given in order to corroborate our claim. An eventual non-zero measurement of these EDMs can be used to disentangle the different sources and strengths of CP-violation.

TWO-PION EXCHANGE NUCLEON-NUCLEON POTENTIAL: O(q 4 ) RELATIVISTIC CHIRAL EXPANSION

We present a relativistic procedure for the chiral expansion of the two-pion exchange component of the NN potential, which emphasizes the role of intermediate πN subamplitudes. The relationship between power counting in πN and NN processes is discussed and results are expressed directly in terms of observable subthreshold coefficients. Interactions are determined by one- and two-loop diagrams, involving pions, nucleons, and other degrees of freedom, frozen into empirical subthreshold coefficients. The full evaluation of these diagrams producesamplitudes containing many different loop integrals. Their simplification by means of relations among these integrals leads to a set of intermediate results. Subsequent truncation to O(q 4 ) yields the relativistic potential, which depends on six loop integrals, representing bubble, triangle, crossed box, and box diagrams. The bubble and triangle integrals are the same as in πN scattering and we have shown that they also determine the chiral structures of box and crossed box integrals. Relativistic threshold effects make our results to be not equivalent with those of the heavy baryon approach. Performing a formal expansion of our results in inverse powers of the nucleon mass, even in regions where this expansion is not valid, we recover most of the standard heavy baryon results. The main differences are due to the Goldberger-Treiman discrepancy and terms of O(q 3 ), possibly associated with the iteration of the one-pion exchange potential.

Relativistic O ( q 4 ) two-pion exchange nucleon-nucleon potential: Configuration space

We have recently performed a relativistic

Peripheral N α scattering: A tool for identifying the two pion exchange component of the NN potential

O({q}^{4})

Dipole-dipole dispersion interactions between neutrons

chiral expansion of the two-pion exchange

Fate of the neutron–deuteron virtual state as an Efimov level

NN

The Casimir--Polder Interaction Between Two Neutrons and Possible Relevance to Tetraneutron States

potential, and here we explore its configuration space content. Interactions are determined by three families of diagrams, two of which involve just

Radiative 3He(\(\alpha , \gamma\))7Be reaction in halo effective field theory

{g}_{A}

Radiative 3He(

and

\alpha , \gamma

{f}_{ensuremath{pi}}