Constraining Star Formation Histories of Blue Galaxies using the Scatter between Stellar Mass and Halo Mass

Understand

We present constraints on the timescale of star formation variability and the correlation between star formation and host halo accretion histories of star-forming (SF) central galaxies from the scatter of the stellar-to-halo mass relation (SHMR).

• SF galaxies are found to have a tight relationship between their star formation rates and stellar masses on the so-called "star-forming sequence" (SFS), which characterizes their SF histories and $M_*$ growths.
• Meanwhile, observed SHMR constraints connect $M_*$ growth to halo accretion history.
• Combining these observed trends with a cosmological $N$-body simulation, we present flexible models that track the SF, $M_*$, and halo accretion histories of SF central galaxies at $z<1$ while reproducing the observed stellar mass function and SFS in SDSS DR7.