%0 Generic %1 bordoloi2017fundamental %A Bordoloi, Rongmon %A Prochaska, J. Xavier %A Tumlinson, Jason %A Werk, Jessica K. %A Tripp, Todd M. %A Burchett, Joseph N. %D 2017 %K CGM fundamental plane %T On the CGM Fundamental Plane: The Halo Mass Dependency of Circumgalactic HI %U http://arxiv.org/abs/1712.02348 %X We analyze the equivalent widths of HI Ly-$\alpha$ ($W_Ly\alpha$) from the inner (R < 160 kpc) circumgalactic medium (CGM) of 85 galaxies at $z 0$ with stellar masses $M*$ ranging $8 log M* / M_ødot 11.6$. Across three orders of magnitude in stellar mass, the CGM of present-day galaxies exhibits a very high covering fraction of cool hydrogen gas ($f_C = 86.6 \pm 3.6$%) indicating that the CGM is ubiquitous in modern, isolated galaxies. These same galaxies show a decline in $W_Ly\alpha$ with increasing radius, independent of mass, but the scatter in this trend correlates closely with $M*$. Using the radial and stellar mass correlations, we construct a fundamental plane describing the cool CGM of modern galaxies: $W^s_HI 1215 \; = \; (0.34 0.02) -( 0.0026 0.0005)*(R) + (0.286 0.002)* (M_*/M_ødot)$. The RMS scatter around this bivariate relation is $\sim$0.2 dex. We interpret the explicit correlation between $W_Ly\alpha$ and $M*$ to arise from the underlying dark matter halo, i.e., $W_Ly\alpha$ traces the gravitational potential whereas $M*$ tracks $M_halo$.

@misc{bordoloi2017fundamental, abstract = {We analyze the equivalent widths of HI Ly-$\alpha$ ($W_{Ly\alpha}$) from the inner (R < 160 kpc) circumgalactic medium (CGM) of 85 galaxies at $z \sim 0$ with stellar masses $M*$ ranging $8 \leq log M* / M_{\odot} \leq 11.6$. Across three orders of magnitude in stellar mass, the CGM of present-day galaxies exhibits a very high covering fraction of cool hydrogen gas ($f_C = 86.6 \pm 3.6$%) indicating that the CGM is ubiquitous in modern, isolated galaxies. These same galaxies show a decline in $W_{Ly\alpha}$ with increasing radius, independent of mass, but the scatter in this trend correlates closely with $M*$. Using the radial and stellar mass correlations, we construct a fundamental plane describing the cool CGM of modern galaxies: $\log W^{s}_{HI 1215} \; = \; (0.34 \pm 0.02) -( 0.0026 \pm 0.0005)*(R) + (0.286 \pm 0.002)* \log (M_{*}/M_{\odot})$. The RMS scatter around this bivariate relation is $\sim$0.2 dex. We interpret the explicit correlation between $W_{Ly\alpha}$ and $M*$ to arise from the underlying dark matter halo, i.e., $W_{Ly\alpha}$ traces the gravitational potential whereas $M*$ tracks $M_{halo}$.}, added-at = {2017-12-08T09:43:40.000+0100}, author = {Bordoloi, Rongmon and Prochaska, J. Xavier and Tumlinson, Jason and Werk, Jessica K. and Tripp, Todd M. and Burchett, Joseph N.}, biburl = {https://www.bibsonomy.org/bibtex/2f634bc59fd428c560599b9f5eb7b2cee/miki}, description = {[1712.02348] On the CGM Fundamental Plane: The Halo Mass Dependency of Circumgalactic HI}, interhash = {0497d7ba4d4ea37108136b90c33deefa}, intrahash = {f634bc59fd428c560599b9f5eb7b2cee}, keywords = {CGM fundamental plane}, note = {cite arxiv:1712.02348Comment: 6 pages, 4 figures, submitted to ApJL}, timestamp = {2017-12-08T09:43:40.000+0100}, title = {On the CGM Fundamental Plane: The Halo Mass Dependency of Circumgalactic HI}, url = {http://arxiv.org/abs/1712.02348}, year = 2017 }