Time for Accretion, Sigtuna, Sweden, August 6-10, 2018
Date(s) - 06/08/2018 - 10/08/2018
Accreting compact objects are among the most powerful sources of radiation in the Universe. The observed bright emission in X-rays would have been impossible without matter losing its energy to radiation on its way towards a black hole or neutron star. Conversely, emission at the extreme limits of the observed wavelength range, at radio frequencies and in the GeV energy range, is connected to ejection events where matter is accelerated to relativistic speeds. Since the initial discovery in the middle of the 20th century, spectral and timing properties of accreting sources, black hole and neutron star-hosting X-ray binaries and active galactic nuclei, have been studied in the entire available electromagnetic energy range. Yet, the geometry and physical properties of these objects remain highly debated, and different models compete to predict and explain the data. New instruments bring more surprises in the field, such as the recent discovery of the pulsed ultraluminous X-ray sources and transitional millisecond pulsars. https://ttt.astro.su.se/groups/head/accretion18/With substantial advances in computer hardware and numerical algorithms, it has become possible to simulate the environments of the extreme gravitational field, close to the compact objects. It is now time for the simulations to meet observations.