Reignition of Star Formation in Dwarf Galaxies

Anna Wright

ACM SIGHPC/Intel Computational &

Data Science Fellow

Rutgers University

Advisor: Alyson Brooks

September 3, 2018

The Simulations

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Name Type Code ResolutionDark Matter

Particle Mass

Gas Particle Mass

g14 suite Zoom-in Gasoline 65-173 pc~104-105

M⊙

~103-104 M⊙

“Gappy” Dwarf Galaxies

• 109-1010 M⊙

• Field galaxies• Gap of at least 2

Gyr in star formation

3Image Credit: M. Irwin/SDSS-II

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Figure 10 from Christensen et al., 2016

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Summary

• A dwarf galaxy quenched by reionization is not necessarily permanently quenched

• Star formation can be reignited when ram pressure from an interaction with a dense stream of gas in the intergalactic medium causes halo gas to collapse onto the disk of a galaxy

• Dwarf galaxies in which star formation has been reignited by this process have high MHI/M* at z=0, even if the reignition event took place several Gyr ago arXiv:1802.03019

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Figure

4,

panel d f

rom

Weis

z et

al.,

2014

Figure

8 f

rom

Weis

z et

al.,

2014