Iwasawa invariants in residually reducible Hida families

We study the variation of $\mu$-invariants of modular forms in a cuspidal Hida family in the case that the family intersects an Eisenstein family. We allow for intersections that occur because of “trivial zeros” (that is, because $p$ divides an Euler factor) as in Mazur’s Eisenstein ideal paper, and pay special attention to the case of the 5-adic family passing through the elliptic curve $X_0(11)$.