One‐level densities in families of Grössencharakters associated to CM elliptic curves

Abstract We study the low‐lying zeros of a family of ‐functions attached to the complex multiplication elliptic curve , for each odd and square‐free integer . Specifically, upon writing the ‐function of as for the appropriate Grössencharakter of conductor , we consider the collection of ‐functions attached to , , where for each integer , denotes the primitive character inducing . We observe that of the ‐functions in have negative root number. is thus not one of the essentially homogeneous families of the universality conjecture of Sarnak, Shin and Templier [33], with unitary, symplectic or orthogonal (odd or even) symmetry type. By computing the one‐level density in the family of ‐functions in with conductor at most , we find that naturally decomposes into subfamilies: more specifically, a collection of symplectic ( for , even) and orthogonal ( for , odd) subfamilies. For each such subfamily, we moreover compute explicit lower order terms in decreasing powers of .