# Colorado Ultraviolet Transit Experiment Data Simulator

## TL;DR

The paper introduces a data simulator for the Colorado Ultraviolet Transit Experiment (CUTE), aiding in mission planning, target selection, and pipeline development for studying exoplanet atmospheres via ultraviolet transit spectroscopy.

## Contribution

It presents a novel data simulation tool for CUTE, supporting mission design, target prioritization, and pipeline testing, adaptable to similar future missions.

## Key findings

- Simulated transit depth measurement precision varies with star temperature and brightness.
- Estimated impact of spacecraft jitter on spectral resolution.
- Validated the simulator with HD209458 system data.

## Abstract

The Colorado Ultraviolet Transit Experiment (CUTE) is a 6U NASA CubeSat carrying on-board a low-resolution (R~2000--3000), near-ultraviolet (2500--3300 {\AA}) spectrograph. It has a rectangular primary Cassegrain telescope to maximize the collecting area. CUTE, which is planned for launch in Spring 2020, is designed to monitor transiting extra-solar planets orbiting bright, nearby stars aiming at improving our understanding of planet atmospheric escape and star-planet interaction processes. We present here the CUTE data simulator, which we complemented with a basic data reduction pipeline. This pipeline will be then updated once the final CUTE data reduction pipeline is developed. We show here the application of the simulator to the HD209458 system and a first estimate of the precision on the measurement of the transit depth as a function of temperature and magnitude of the host star. We also present estimates of the effect of spacecraft jitter on the final spectral resolution. The simulator has been developed considering also scalability and adaptability to other missions carrying on-board a long-slit spectrograph. The data simulator will be used to inform the CUTE target selection, choose the spacecraft and instrument settings for each observation, and construct synthetic CUTE wavelength-dependent transit light curves on which to develop the CUTE data reduction pipeline.