In this contribution we report on a kinematic study for 33 early type galaxies (ETGs) into their outer halos (average 6 effective radii, Re). We use planetary nebulae (PNe) as tracers of the main stellar population at large radii, where absorption line spectroscopy is no longer feasible. The ePN.S survey is the largest survey to-date of ETG kinematics with PNe, based on data from the Planetary Nebula Spectrograph (PN.S), counter-dispersed imaging, and highresolution PN spectroscopy. We find that ETGs typically show a kinematic transition between inner regions and halos. Slow rotators have increased rotational support at large radii. Most of the ePN.S fast rotators show a decrease in rotation, due to the fading of the stellar disk in the outer, more slowly rotating spheroid. 30% of these fast rotators are dominated by rotation also at large radii, 40% show kinematic twists or misalignments, indicating a transition from oblate to triaxial in the halo. Despite this variety of kinematic behaviors, the ePN.S ETG halos have similar angular momentum content, independently of fast/slow rotation of the central regions. Estimated kinematic transition radii in units of Re are ∼ 1 − 3 Re and anti-correlate with stellar mass. These results are consistent with cosmological simulations and support a two-phase formation scenario for ETGs.
Recent advances in high-throughput
experimentation for combinatorial
studies have accelerated the discovery and analysis of materials across
a wide range of compositions and synthesis conditions. However, many
of the more powerful characterization methods are limited by speed,
cost, availability, and/or resolution. To make efficient use of these
methods, there is value in developing approaches for identifying critical
compositions and conditions to be used as a priori knowledge for follow-up characterization with high-precision techniques,
such as micrometer-scale synchrotron-based X-ray diffraction (XRD).
Here, we demonstrate the use of optical microscopy and reflectance
spectroscopy to identify likely phase-change boundaries in thin film
libraries. These methods are used to delineate possible metastable
phase boundaries following lateral-gradient laser spike annealing
(lg-LSA) of oxide materials. The set of boundaries are then compared
with definitive determinations of structural transformations obtained
using high-resolution XRD. We demonstrate that the optical methods
detect more than 95% of the structural transformations in a composition-gradient
La-Mn-O library and a Ga2O3 sample, both subject
to an extensive set of lg-LSA anneals. Our results provide quantitative
support for the value of optically detected transformations as a priori data to guide subsequent structural characterization,
ultimately accelerating and enhancing the efficient implementation
of micrometer-resolution XRD experiments.
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