1 INTRODUCTION  
2 SAMPLES  
2.1 The Surveys and Catalogues  
2.2 The Sky Regions Used  
2.3 The Optical Sample  
2.4 The X-ray Sample  
3 CROSS MATCHING THE redMaPPer AND XCS SAMPLES  
3.1 X-ray to Optical Matching  
3.2 Optical to X-ray Matching  
3.3 redMaPPer Clusters Undetected in X-ray Observations  
4 X-RAY ANALYSIS  
4.1 Recovering X-ray temperature and luminosities  
4.2 Samples used for recovering temperatures and luminosities  
5 SCALING RELATIONS  
5.1 Fitting the data  
5.2 Fitted scaling relations  
6 DISCUSSION  
6.1 Scaling relations  
6.2 Comparison to previous studies  
6.3 Predicted X-ray cluster detections in the era of the Rubin Observatory  
7 SUMMARY