# MOCK THETA FUNCTIONS OF ORDER 2 AND THEIR SHADOW COMPUTATIONS

• Kang, Soon-Yi (Department of Mathematics Kangwon National University) ;
• Swisher, Holly (Department of Mathematics Kangwon National University)
• Accepted : 2017.01.12
• Published : 2017.11.30

#### Abstract

Zwegers showed that a mock theta function can be completed to form essentially a real analytic modular form of weight 1/2 by adding a period integral of a certain weight 3/2 unary theta series. This theta series is related to the holomorphic modular form called the shadow of the mock theta function. In this paper, we discuss the computation of shadows of the second order mock theta functions and show that they share the same shadow with a mock theta function which appears in the Mathieu moonshine phenomenon.

#### Acknowledgement

Supported by : National Research Foundation of Korea(NRF)

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