TY - JOUR
T1 - Environmental regulation of cloud and star formation in galactic bars
AU - Renaud, F.
AU - Bournaud, F.
AU - Emsellem, E.
AU - Agertz, O.
AU - Athanassoula, E.
AU - Combes, F.
AU - Elmegreen, B.
AU - Kraljic, K.
AU - Motte, F.
AU - Teyssier, R.
N1 - Funding Information:
We thank the reviewer for a report that helped improve the clarity of the paper. This work was granted access to the PRACE Research Infrastructure resource Curie hosted at the TGCC, France (PRACE project ra-0283), and national GENCI resources (projects 2013, 2014, 2015-GEN2192). FR and FB acknowledge support from the European Research Council through grant nos. ERC-StG-335936 and ERC-StG-257720. EA acknowledges financial support from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007-2013/under REA grant agreement no. PITN-GA-2011-289313 to the DAGAL network and from the CNES (Centre National d'Etudes Spatiales - France). FC acknowledges the European Research Council for the Advanced Grant Programme no. 267399-Momentum. KK acknowledges support from grant Spin(e) ANR-13-BS05-0005 of the french ANR.
Funding Information:
We thank the reviewer for a report that helped improve the clarity of the paper. This work was granted access to the PRACE Research Infrastructure resource Curie hosted at the TGCC, France (PRACE project ra-0283), and national GENCI resources (projects 2013, 2014, 2015-GEN2192). FR and FB acknowledge support from the European Research Council through grant nos. ERC-StG-335936 and ERC-StG-257720. EA acknowledges financial support from the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme FP7/2007-2013/ under REA grant agreement no. PITN-GA-2011-289313 to the DAGAL network and from the CNES (Centre National d’Etudes Spatiales – France). FC acknowledges the European Research Council for the Advanced Grant Programme no. 267399-Momentum. KK acknowledges support from grant Spin(e) ANR-13-BS05-0005 of the french ANR.
Publisher Copyright:
© 2015 The Author.
PY - 2015/12/11
Y1 - 2015/12/11
N2 - The strong time-dependence of the dynamics of galactic bars yields a complex and rapidly evolving distribution of dense gas and star forming regions. Although bars mainly host regions void of any star formation activity, their extremities can gather the physical conditions for the formation of molecular complexes and mini-starbursts. Using a sub-parsec resolution hydrodynamical simulation of a Milky Way-like galaxy, we probe these conditions to explore how and where bar (hydro-)dynamics favours the formation or destruction of molecular clouds and stars. The interplay between the kpc-scale dynamics (gas flows, shear) and the parsecscale (turbulence) is key to this problem. We find a strong dichotomy between the leading and trailing sides of the bar, in term of cloud fragmentation and in the age distribution of the young stars. After orbiting along the bar edge, these young structures slow down at the extremities of the bar, where orbital crowding increases the probability of cloud-cloud collision. We find that such events increase the Mach number of the cloud, leading to an enhanced star formation efficiency and finally the formation of massive stellar associations, in a fashion similar to galaxy-galaxy interactions. We highlight the role of bar dynamics in decoupling young stars from the clouds in which they form, and discuss the implications on the injection of feedback into the interstellar medium (ISM), in particular in the context of galaxy formation.
AB - The strong time-dependence of the dynamics of galactic bars yields a complex and rapidly evolving distribution of dense gas and star forming regions. Although bars mainly host regions void of any star formation activity, their extremities can gather the physical conditions for the formation of molecular complexes and mini-starbursts. Using a sub-parsec resolution hydrodynamical simulation of a Milky Way-like galaxy, we probe these conditions to explore how and where bar (hydro-)dynamics favours the formation or destruction of molecular clouds and stars. The interplay between the kpc-scale dynamics (gas flows, shear) and the parsecscale (turbulence) is key to this problem. We find a strong dichotomy between the leading and trailing sides of the bar, in term of cloud fragmentation and in the age distribution of the young stars. After orbiting along the bar edge, these young structures slow down at the extremities of the bar, where orbital crowding increases the probability of cloud-cloud collision. We find that such events increase the Mach number of the cloud, leading to an enhanced star formation efficiency and finally the formation of massive stellar associations, in a fashion similar to galaxy-galaxy interactions. We highlight the role of bar dynamics in decoupling young stars from the clouds in which they form, and discuss the implications on the injection of feedback into the interstellar medium (ISM), in particular in the context of galaxy formation.
KW - ISM: structure -Galaxy: structure
KW - Methods: numerical
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U2 - 10.1093/mnras/stv2223
DO - 10.1093/mnras/stv2223
M3 - Article
AN - SCOPUS:84962555362
SN - 0035-8711
VL - 454
SP - 3299
EP - 3310
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -