p-adic interpolation of Gauss--Manin connections on nearly overconvergent modular forms and p-adic L-functions

In this paper, we give a new geometric definition of nearly overconvergent modular forms and $p$-adically interpolate the Gauss-Manin connection on this space. This can be seen as an ``overconvergent’’ version of the unipotent circle action on the space of $p$-adic modular forms, as constructed by Gouvêa and Howe. This improves on results of Andreatta–Iovita and has applications to the construction of Rankin–Selberg and triple product $p$-adic $L$-functions.