Pindor$^{4,6}$, K. Takahashi$^1$, H. Tashiro$^2$, C. M. Trott$^{5,6,7}$\
    $^{1}$Department of Physics, Kumamoto University, Kumamoto,Japan\
    $^2$Department of Physics and Astrophysics, Nagoya University Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan\
    $^3$Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya University Nagoya, 464-8602, Japan\
    $^4$ARC Centre of Excellence for All-sky Astrophysics (CAASTRO)\
    $^5$International Centre for Radio Astronomy Research, Curtin University, Perth, WA 6845, Australia\
    $^6$School of Physics, The University of Melbourne, Parkville, VIC 3010, Australia\
    $^7$ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D)
title: Study of systematics effects on the Cross Power Spectrum of 21cm Line and Cosmic Microwave Background using Murchison Widefield Array Data
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cosmology: dark ages, reionization, first stars

Introduction
============

At the end of the Dark Ages, the first stars were born in dense clouds and started to ionize neutral hydrogen (${\ion{H}{i}}$). As a result of the cosmological structure formation, young galaxies and active galactic nuclei created large ionized bubbles around them. According to observations of high-$z$ QSO spectra, almost all of the ${\ion{H}{i}}$ gas was ionized by $z\,\sim \,6$ [@2006AJ....132..117F]. This is the epoch of reionization (EoR) and a measurement of its precise history is a primary motivation of current observational 