The Milky Way like galaxy NGC 6384 and its nuclear star cluster at high NIR spatial resolution using LBT/ARGOS commissioning data. (arXiv:1901.06350v1 [astro-ph.GA])

The Milky Way like galaxy NGC 6384 and its nuclear star cluster at high NIR spatial resolution using LBT/ARGOS commissioning data. (arXiv:1901.06350v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Georgiev_I/0/1/0/all/0/1">Iskren Y. Georgiev</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Neumayer_N/0/1/0/all/0/1">Nadine Neumayer</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Gaessler_W/0/1/0/all/0/1">Wolfgang Gaessler</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rabien_S/0/1/0/all/0/1">Sebastian Rabien</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Busoni_L/0/1/0/all/0/1">Lorenzo Busoni</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bonaglia_M/0/1/0/all/0/1">Marco Bonaglia</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ziegleder_J/0/1/0/all/0/1">Julian Ziegleder</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Xivry_G/0/1/0/all/0/1">Gilles Orban de Xivry</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Peter_D/0/1/0/all/0/1">Diethard Peter</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kulas_M/0/1/0/all/0/1">Martin Kulas</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Borelli_J/0/1/0/all/0/1">Jose Borelli</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rahmer_G/0/1/0/all/0/1">Gustavo Rahmer</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lefebvre_M/0/1/0/all/0/1">Michael Lefebvre</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Baumgardt_H/0/1/0/all/0/1">Holger Baumgardt</a>

We analyse high spatial resolution near infra-red (NIR) imaging of NGC6384, a
Milky Way like galaxy, using ARGOS commissioning data at the Large Binocular
Telescope (LBT). ARGOS provides a stable PSF$_{rm FWHM}!=!0.2″!-!0.3″$ AO
correction of the ground layer across the LUCI2 NIR camera $4′!times4’$ field
by using six laser guide stars (three per telescope) and a natural guide star
for tip-tilt sensing and guiding. Enabled by this high spatial resolution we
analyse the structure of the nuclear star cluster (NSC) and the central
kiloparsec of NGC6384. We find via 2D modelling that the NSC ($r_{rm
eff}!simeq!10$pc) is surrounded by a small ($r_{rm eff}!simeq!100$pc)
and a larger Sersi’c ($r_{rm eff}!simeq!400$pc), all embedded within the
NGC,6384 large-scale boxy/X-shaped bulge and disk. This proof-of-concept study
shows that with the high spatial resolution achieved by ground-layer AO we can
push such analysis to distances previously only accessible from space.
SED-fitting to the NIR and optical HST photometry allowed to leverage the
age-metallicity-extinction degeneracies and derive the effective NSC properties
of an young to old population mass ratio of $8%$ with ${cal
M}_{rmstar,old}!simeq!3.5times10^7M_odot$, Age$_{rm old,
young}!=!10.9pm1.3$Gyr and 226,Myr $pm62%$, metallicity
[M/H]$=!-0.11pm0.16$ and $0.33pm39%$dex, and $E(B!-!V)!=!0.63$ and
1.44mag.

We analyse high spatial resolution near infra-red (NIR) imaging of NGC6384, a
Milky Way like galaxy, using ARGOS commissioning data at the Large Binocular
Telescope (LBT). ARGOS provides a stable PSF$_{rm FWHM}!=!0.2″!-!0.3″$ AO
correction of the ground layer across the LUCI2 NIR camera $4′!times4’$ field
by using six laser guide stars (three per telescope) and a natural guide star
for tip-tilt sensing and guiding. Enabled by this high spatial resolution we
analyse the structure of the nuclear star cluster (NSC) and the central
kiloparsec of NGC6384. We find via 2D modelling that the NSC ($r_{rm
eff}!simeq!10$pc) is surrounded by a small ($r_{rm eff}!simeq!100$pc)
and a larger Sersi’c ($r_{rm eff}!simeq!400$pc), all embedded within the
NGC,6384 large-scale boxy/X-shaped bulge and disk. This proof-of-concept study
shows that with the high spatial resolution achieved by ground-layer AO we can
push such analysis to distances previously only accessible from space.
SED-fitting to the NIR and optical HST photometry allowed to leverage the
age-metallicity-extinction degeneracies and derive the effective NSC properties
of an young to old population mass ratio of $8%$ with ${cal
M}_{rmstar,old}!simeq!3.5times10^7M_odot$, Age$_{rm old,
young}!=!10.9pm1.3$Gyr and 226,Myr $pm62%$, metallicity
[M/H]$=!-0.11pm0.16$ and $0.33pm39%$dex, and $E(B!-!V)!=!0.63$ and
1.44mag.

http://arxiv.org/icons/sfx.gif