Published online by Cambridge University Press: 17 April 2019
In this paper various analytic techniques are combined in order to study the average of a product of a Hecke $L$-function and a symmetric square $L$-function at the central point in the weight aspect. The evaluation of the second main term relies on the theory of Maaß forms of half-integral weight and the Rankin–Selberg method. The error terms are bounded using the Liouville–Green approximation.
The research of Olga Balkanova is supported by Academy of Finland project no. 293876. Gautami Bhowmik acknowledges support from the Labex CEMPI. The research of Dmitry Frolenkov is supported by the Foundation for the Advancement of Theoretical Physics and Mathematics BASIS. Nicole Raulf acknowledges support from the Labex CEMPI.