Author: Cherenkov Telescope Array Observatory; Cherenkov Telescope Array ConsortiumContact: open-data@cta-observatory.org The Cherenkov Telescope Array Observatory (CTAO) will be the next-generation gamma-ray observatory and is currently under construction on the island of La Palma (Spain) and near Paranal (Chile). This repository provides access to reconstructed event information (DL2- and DL1-level, simulation parameters) from Monte Carlo simulations of the CTAO Northern Array (production 5). The Monte Carlo simulations for prod5 are described in arXiv:2108.04512, the simulation telescopes models used in the telescope simulation program sim_telarray and the configuration used in the air-shower code CORSIKA are available from the Zenodo archive for CTA Prod5 Telescope Models. MC events are calibrated and reconstructed using the ctapipe package and stored for the following data levels: R1-MC: simulated raw data (output from sim_telarray) DL1 (this repository): telescope level data including images and image parameters DL2 (this repository): reconstructed event parameters such as energy, direction, gamma/hadron discrimination parameters. Note that this repository only contains the direction information. DL3: selected events with associated instrument response functions (IRFs). Preliminary DL3-IRFs are available from [here](https://doi.org/10.5281/zenodo.5499839). For a description of the file format and data model, see ctapipe Data Model. Data set description: using ctapipe version 0.17 (GitHub release page, Zenodo page) CTAO Northern Array on La Palma for the Alpha configuration (4 large-sized telescopes, 9 mid-sized telescopes) Zenith angles of 20 deg, telescope pointing direction north and south Primary particles: photons, protons Contained information: DL1 image and parameter data, DL2 geometry, simulation truths For convenience, the same data is provided in a single, large file per particle type for the whole dataset which do not contain the low-level DL1 image information and a larger number of files including this information. We explicitly note that the products provided are preliminary and do not reflect the final performance of the CTA Observatory, neither are data structure or formats finalized. We also note that these data products are different to those used for the CTAO Instrument Response Functions.In cases in which the data provided in this repository are used in a research project, we ask that the following acknowledgment is added in any resulting publication: "This research has made use of the CTA DL1 and DL2 Event lists provided by the CTA Observatory and Consortium (version prod5-DL2-release1-DL2)" and cite this repository in the reference section of your publication. We would like to thank the computing centers that provided resources for the generation of the Prod5 simulation set, click here for a list of service providers.