## 5 Conclusions and Outlook  
In this work, a novel setup is demonstrated which can record the time of arrival of individual X-rays and inelastically scattered electrons with nanosecond precision.  
The advantage of this method is that it reveals correlation data while preserving the full EELS and EDX signal without compromise in speed or acquisition time. We demonstrate that the correlation information provides several important advantages on top of simply merging two independent spectral channels. Model-free background subtraction takes away the requirement of having to fit a model background in a fitting region and is especially interesting in cases where overlapping edges occur. We show that coincidence detection provides a benefit for low-concentration elements in the presence of a high background as would occur in cases relating to doping and trace elements; typically, topics which are hard or even impossible to treat with EELS despite its very favorable detection efficiency.  
We identified the single most important parameter to further improve detection limits in coincidence detection between core-loss EELS and EDX to be the limited time resolution due to large area SDD detectors that are commonly used in modern TEM setups. The most optimal way to make progress here would be to redesign the EDX detectors with the requirement of both high collection efficiency and good time resolution. We estimate that another factor 10-100 could be achievable which would have a similar effect as improving the electron dose by that same factor without the downside of beam damage or drift.  
The novel method of detecting single events instead of the integrated signal, opens up possibilities for other types of scattering phenomena where signals are correlated with each other in time such as EELS-CL, secondary electrons-EELS and many more. The intrinsic data compression by storing only actual events, the lack of readout time and the fact that synchronization between multiple detectors is reduced to the problem of syncing them all to a single master clock holds many benefits for implementation in TEM setups with their ever-increasing number of detectors and datarates.  
Conceptualization, J.V. and K.M.-C.; Development experimental setup, D.J., A.B., K.M.[PERSON]C. and J.V.; Experimental data acquisition, D.J.; Data analysis, D.J.; writing-original draft preparation, D.J.; writing-review and editing, A.B., [PERSON] and J.V. All authors have read and agreed to the published version of the manuscript.  
This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 823717 ESTEM3. [PERSON], [PERSON] and [PERSON] acknowledge funding from FWO project G042920N 'Coincident event detection for advanced spectroscopy in transmission electron microscopy'. We acknowledge funding under the European Union's Horizon 2020 research and innovation program ([PERSON] and [PERSON] under grant agreement No 101017720, FET-Proactive EBEM). [PERSON] acknowledges funding from the Helmholtz society under contract VH-NG-1317.  
The full datasets and software are made available on Zenodo [18].  
The authors would like to express their gratitude to [PERSON] for significant help with scan engine, to [PERSON] for fruitful discussions, to [PERSON] for help with video port on Gatan imaging filter and [PERSON] of the University of Hasselt for providing the diamond test sample.  
The authors declare no conflict of interest.