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Searching for fluctuations in the IGM temperature using the Lyman alpha forest

Matias Zaldarriaga
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Abstract

We propose a statistical method to search for fluctuations in the temperature of the intergalactic medium (IGM) using the Lyman $α$ forest. The power on small scales ($\sim 25 \km/\s$) is used as a thermometer and fluctuations of this power are constrained. The method is illustrated using Q1422+231. We see no evidence of temperature fluctuations. We show that in a model with two temperatures that occupy comparable fractions of the spectra, the ratio of small scale powers is constrained to be smaller than 3.5 (corresponding to a factor of 2.5 in temperature). We show that approximately ten quasars are needed constrain factors of two fluctuations in small scale power power.

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Matias Zaldarriaga. 2001-02-12. Searching for fluctuations in the IGM temperature using the Lyman alpha forest. https://doi.org/10.1086/324212

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