TY - JOUR
KW - Space and Planetary Science
KW - Astronomy and Astrophysics
AU - Emma Lieb
AU - Angela Collier
AU - Ann-Marie Madigan
AB - An overwhelming majority of galactic spiral arms trail with respect to the rotation of the galaxy, though a small sample of leading spiral arms has been observed. The formation of these leading spirals is not well understood. Here we show, using collisionless N-body simulations, that a barred disc galaxy in a retrograde dark matter halo can produce long-lived (∼3 Gyr) leading spiral arms. Due to the strong resonant coupling of the disc to the halo, the bar slows rapidly and spiral perturbations are forced ahead of the bar. We predict that such a system, if observed, will also host a dark matter wake oriented perpendicular to the stellar bar. More generally, we propose that any mechanism that rapidly decelerates the stellar bar will allow leading spiral arms to flourish.
BT - Monthly Notices of the Royal Astronomical Society
DA - 2021-10
DO - 10.1093/mnras/stab2904
IS - 1
N2 - An overwhelming majority of galactic spiral arms trail with respect to the rotation of the galaxy, though a small sample of leading spiral arms has been observed. The formation of these leading spirals is not well understood. Here we show, using collisionless N-body simulations, that a barred disc galaxy in a retrograde dark matter halo can produce long-lived (∼3 Gyr) leading spiral arms. Due to the strong resonant coupling of the disc to the halo, the bar slows rapidly and spiral perturbations are forced ahead of the bar. We predict that such a system, if observed, will also host a dark matter wake oriented perpendicular to the stellar bar. More generally, we propose that any mechanism that rapidly decelerates the stellar bar will allow leading spiral arms to flourish.
PB - Oxford University Press (OUP)
PY - 2021
SP - 685
EP - 692
T2 - Monthly Notices of the Royal Astronomical Society
TI - Bar-driven leading spiral arms in a counter-rotating dark matter halo
UR - https://academic.oup.com/mnras/article/509/1/685/6384839?login=true
VL - 509
SN - 0035-8711, 1365-2966
ER -