%0 Generic %1 tomaselli2021lymanalpha %A Tomaselli, Giovanni Maria %A Ferrara, Andrea %D 2021 %K library %T Lyman-alpha radiation pressure: an analytical exploration %U http://arxiv.org/abs/2103.14655 %X We study radiation pressure due to Lyman alpha line photons, obtaining and exploring analytical expressions for the force-multiplier, $M_F(N_H, Z) = F_\alpha/(L_\alpha/c)$, as a function of gas column density, $N_H$, and metallicity, $Z$, for both dust-free and dusty media, employing a WKB approach for the latter case. Solutions for frequency offset emission to emulate non-static media moving with a bulk velocity $v$, have also been obtained. We find that, in static media, Ly$\alpha$ pressure dominates over both photoionization and dust-mediated UV radiation pressure in a very wide parameter range ($16 < N_H < 23$; $-4 < łogZ/Z_ødot < 0$). For example, it overwhelms the other two forces by 10 (300) times in standard (low-$Z$) star-forming clouds. Thus, in agreement with previous studies, we conclude that Ly$\alpha$ pressure plays a dominant role in the initial acceleration of the gas around luminous sources, and must be implemented in galaxy formation, evolution and outflow models and simulations.

@misc{tomaselli2021lymanalpha, abstract = {We study radiation pressure due to Lyman alpha line photons, obtaining and exploring analytical expressions for the force-multiplier, $M_F(N_H, Z) = F_\alpha/(L_\alpha/c)$, as a function of gas column density, $N_H$, and metallicity, $Z$, for both dust-free and dusty media, employing a WKB approach for the latter case. Solutions for frequency offset emission to emulate non-static media moving with a bulk velocity $v$, have also been obtained. We find that, in static media, Ly$\alpha$ pressure dominates over both photoionization and dust-mediated UV radiation pressure in a very wide parameter range ($16 < \log N_H < 23$; $-4 < \log[Z/Z_\odot] < 0$). For example, it overwhelms the other two forces by 10 (300) times in standard (low-$Z$) star-forming clouds. Thus, in agreement with previous studies, we conclude that Ly$\alpha$ pressure plays a dominant role in the initial acceleration of the gas around luminous sources, and must be implemented in galaxy formation, evolution and outflow models and simulations.}, added-at = {2021-03-30T08:08:33.000+0200}, author = {Tomaselli, Giovanni Maria and Ferrara, Andrea}, biburl = {https://www.bibsonomy.org/bibtex/295d7e39adae572e6db274f51cb59c202/gpkulkarni}, description = {Lyman-alpha radiation pressure: an analytical exploration}, interhash = {4b484b5a87a9506da06aca8e8d63c400}, intrahash = {95d7e39adae572e6db274f51cb59c202}, keywords = {library}, note = {cite arxiv:2103.14655}, timestamp = {2021-03-30T08:08:33.000+0200}, title = {Lyman-alpha radiation pressure: an analytical exploration}, url = {http://arxiv.org/abs/2103.14655}, year = 2021 }