TY - JOUR

T1 - The impact of the halo spin-concentration relation on disc scaling laws

AU - Posti, Lorenzo

AU - Famaey, Benoit

AU - Pezzulli, Gabriele

AU - Fraternali, Filippo

AU - Ibata, Rodrigo

AU - Marasco, Antonino

PY - 2020/12/1

Y1 - 2020/12/1

N2 - Galaxy scaling laws, such as the Tully-Fisher, mass-size, and Fall
relations, can provide extremely useful clues on our understanding of
galaxy formation in a cosmological context. Some of these relations are
extremely tight and well described by one single parameter (mass),
despite the theoretical existence of secondary parameters such as spin
and concentration, which are believed to impact these relations. In
fact, the residuals of these scaling laws appear to be almost
uncorrelated with each other, posing significant constraints on models
where secondary parameters play an important role. Here, we show that a
possible solution is that such secondary parameters are correlated
amongst themselves, in a way that removes correlations in observable
space. In particular, we focus on how the existence of an
anti-correlation between the dark matter halo spin and its
concentration, which is still debated in simulations, can weaken the
correlation of the residuals of the Tully-Fisher and mass-size
relations. Interestingly, in using simple analytic galaxy formation
models, we find that this happens only for a relatively small portion of
the parameter space that we explored, which suggests that this idea
could be used to derive constraints on galaxy formation models that have
yet to be explored.

AB - Galaxy scaling laws, such as the Tully-Fisher, mass-size, and Fall
relations, can provide extremely useful clues on our understanding of
galaxy formation in a cosmological context. Some of these relations are
extremely tight and well described by one single parameter (mass),
despite the theoretical existence of secondary parameters such as spin
and concentration, which are believed to impact these relations. In
fact, the residuals of these scaling laws appear to be almost
uncorrelated with each other, posing significant constraints on models
where secondary parameters play an important role. Here, we show that a
possible solution is that such secondary parameters are correlated
amongst themselves, in a way that removes correlations in observable
space. In particular, we focus on how the existence of an
anti-correlation between the dark matter halo spin and its
concentration, which is still debated in simulations, can weaken the
correlation of the residuals of the Tully-Fisher and mass-size
relations. Interestingly, in using simple analytic galaxy formation
models, we find that this happens only for a relatively small portion of
the parameter space that we explored, which suggests that this idea
could be used to derive constraints on galaxy formation models that have
yet to be explored.

KW - galaxies: kinematics and dynamics

KW - galaxies: spiral

KW - galaxies: structure

KW - galaxies: formation

U2 - 10.1051/0004-6361/202038474

DO - 10.1051/0004-6361/202038474

M3 - Article

SN - 0004-6361

VL - 644

JO - Astronomy & astrophysics

JF - Astronomy & astrophysics

M1 - A76

ER -