Quantifying the effect of field variance on the H$alpha$ luminosity function with the New Numerical Galaxy Catalogue ($nu^2$GC). (arXiv:2004.00815v1 [astro-ph.GA])

Quantifying the effect of field variance on the H$alpha$ luminosity function with the New Numerical Galaxy Catalogue ($nu^2$GC). (arXiv:2004.00815v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Ogura_K/0/1/0/all/0/1">Kazuyuki Ogura</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nagashima_M/0/1/0/all/0/1">Masahiro Nagashima</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shimakawa_R/0/1/0/all/0/1">Rhythm Shimakawa</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hayashi_M/0/1/0/all/0/1">Masao Hayashi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kobayashi_M/0/1/0/all/0/1">Masakazu A. R. Kobayashi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Oogi_T/0/1/0/all/0/1">Taira Oogi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ishiyama_T/0/1/0/all/0/1">Tomoaki Ishiyama</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Koyama_Y/0/1/0/all/0/1">Yusei Koyama</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Makiya_R/0/1/0/all/0/1">Ryu Makiya</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Okoshi_K/0/1/0/all/0/1">Katsuya Okoshi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Onodera_M/0/1/0/all/0/1">Masato Onodera</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shirakata_H/0/1/0/all/0/1">Hikari Shirakata</a>

We construct a model of H$alpha$ emitters (HAEs) based on a semi-analytic
galaxy formation model, the New Numerical Galaxy Catalog ($nu^2$GC). In this
paper, we report our estimate for the field variance of the HAE distribution.
By calculating the H$alpha$ luminosity from the star-formation rate of
galaxies, our model well reproduces the observed H$alpha$ luminosity function
(LF) at $z=0.4$. The large volume of the $nu^2$GC makes it possible to examine
the spatial distribution of HAEs over a region of (411.8 Mpc)$^3$ in the
comoving scale. The surface number density of $z=0.4$ HAEs with $L_{rm
Halpha} geq 10^{40}$ erg s$^{-1}$ is 308.9 deg$^{-2}$. We have confirmed that
the HAE is a useful tracer for the large-scale structure of the Universe
because of their significant overdensity ($>$ 5$sigma$) at clusters and the
filamentary structures. The H$alpha$ LFs within a survey area of $sim$2
deg$^2$ (typical for previous observational studies) show a significant field
variance up to $sim$1 dex. Based on our model, one can estimate the variance
on the H$alpha$ LFs within given survey areas.

We construct a model of H$alpha$ emitters (HAEs) based on a semi-analytic
galaxy formation model, the New Numerical Galaxy Catalog ($nu^2$GC). In this
paper, we report our estimate for the field variance of the HAE distribution.
By calculating the H$alpha$ luminosity from the star-formation rate of
galaxies, our model well reproduces the observed H$alpha$ luminosity function
(LF) at $z=0.4$. The large volume of the $nu^2$GC makes it possible to examine
the spatial distribution of HAEs over a region of (411.8 Mpc)$^3$ in the
comoving scale. The surface number density of $z=0.4$ HAEs with $L_{rm
Halpha} geq 10^{40}$ erg s$^{-1}$ is 308.9 deg$^{-2}$. We have confirmed that
the HAE is a useful tracer for the large-scale structure of the Universe
because of their significant overdensity ($>$ 5$sigma$) at clusters and the
filamentary structures. The H$alpha$ LFs within a survey area of $sim$2
deg$^2$ (typical for previous observational studies) show a significant field
variance up to $sim$1 dex. Based on our model, one can estimate the variance
on the H$alpha$ LFs within given survey areas.

http://arxiv.org/icons/sfx.gif