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arXiv · 1803.00868

Equation of state of the intergalactic medium in the early Universe

K. N. Telikova·S. A. Balashev·P. S. Shternin
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Abstract

Spectroscopy of the Ly$\alpha$ forest in quasar spectra proved to be a useful tool for probing the intergalactic gas. We developed the automatic program for Voigt profile fitting of Ly$\alpha$ forest lines. We run this code on 9 high resolution ($\sim 50000$) quasars spectra with a high signal-to-noise ratio ($\sim 50 -100$) from the Keck telescope archive and obtained the sample of single well-fitted Ly$\alpha$ lines. Fitting the joint 2d distribution of column density and Doppler parameter from this sample by physically reasonable model we estimate a power law index $\gamma$ of the equation of state of the intergalactic medium in the redshift range $z\sim 2-3$. We found that our measurement is in an agreement with measurements by other groups obtained with Voigt profile fitting technique.

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K. N. Telikova, S. A. Balashev, P. S. Shternin. 2018-03-02. Equation of state of the intergalactic medium in the early Universe. https://doi.org/10.1088/1742-6596%2F1038%2F1%2F012015

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