Context : Umbral Dots ( UDs ) are thought to be manifestations of magnetoconvection in sunspot umbrae .
Recent advances in their theoretical description point to the need for a thorough study of their properties and evolution based on data with the highest currently achievable resolution .

Aims : Our UD analysis aims to provide parameters such as lifetimes , diameters , horizontal velocities , and peak intensities , as well as the evolution of selected parameters .

Methods : We present a 106-minute TiO ( 705.7 nm ) time series of high spatial and temporal resolution that contains thousands of UDs in the umbra of a mature sunspot in the active region NOAA 10667 at \mu = 0.95 .
The data were acquired with the 1-m Swedish Solar Telescope ( SST ) on La Palma .
With the help of a multilevel tracking ( MLT ) algorithm the sizes , brightnesses , and trajectories of 12836 umbral dots were found and extensively analyzed .
The MLT allows UDs with very low contrast to be reliably identified .

Results : Inside the umbra we determine a UD filling factor of 11 % .
The histogram of UD lifetimes is monotonic , i.e .
a UD does not have a typical lifetime .
Three quarters of the UDs lived for less than 150 s and showed no or little motion .
The histogram of the UD diameters exhibits a maximum at 225 km , i.e .
most of the UDs are spatially resolved .
UDs display a typical horizontal velocity of 420 m s ^ { -1 } and a typical peak intensity of 51 % of the mean intensity of the quiet photosphere , making them on average 20 % brighter than the local umbral background .
Almost all mobile UDs ( large birth-death distance ) were born close to the umbra-penumbra boundary , move towards the umbral center , and are brighter than average .
Notably bright and mobile UDs were also observed along a prominent UD chain , both ends of which are located at the umbra-penumbra boundary .
Their motion started primarily at either of the ends of the chain , continued along the chain , and ended near the chain ’ s center .
We observed the splitting and merging of UDs and the temporal succession of both .
For the first time the evolution of brightness , size , and horizontal speed of a typical UD could be determined in a statistically significant way .
Considerable differences between the evolution of central and peripheral UDs are found , which point to a difference in origin .

Conclusions :