CheckMATE: Confronting your Favourite New Physics Model with LHC Data

Abstract: In the first three years of running, the LHC has delivered a wealth of new data that is now being analysed. With over 20 fb$^{-1}$ of integrated luminosity, both ATLAS and CMS have performed many searches for new physics that theorists are eager to test their model against. However, tuning the detector simulations, understanding the particular analysis details and interpreting the results can be a tedious task. CheckMATE (Check Models At Terascale Energies) is a program package which accepts simulated event files in many formats for any model. The program then determines whether the model is excluded or not at 95% C.L. by comparing to many recent experimental analyses. Furthermore the program can calculate confidence limits and provide detailed information about signal regions of interest. It is simple to use and the program structure allows for easy extensions to upcoming LHC results in the future. CheckMATE can be found at: http://checkmate.hepforge.org

• The paper introduces CheckMATE, a computational package that compares simulated events with LHC data at a 95% confidence level for model validation.
• It integrates fast detector simulations and statistical analyses to mirror the performance of ATLAS and CMS in exploring BSM scenarios.
• Validation against standard test cases demonstrates CheckMATE’s efficiency in expediting new physics model testing and empirical evaluation.

Summary of "CheckMATE: Confronting your Favourite New Physics Model with LHC Data"

The article "CheckMATE: Confronting your Favourite New Physics Model with LHC Data" discusses the development and application of a computational package named CheckMATE, which is designed to facilitate the comparison of theoretical models involving new physics against experimental data from the Large Hadron Collider (LHC). CheckMATE aims to streamline the process for theorists attempting to validate or refute their models based on the detection results from the LHC, focusing on the efforts of the ATLAS and CMS collaborations in the search for Beyond the Standard Model (BSM) physics.

Key Features and Methodology

CheckMATE operates by inputting simulated event files from a variety of particle physics models and comparing the outcomes with the latest LHC data to determine model viability at the 95% confidence level. It provides a user-friendly interface, allowing users to easily extend the list of included analyses with upcoming data from the LHC. The system integrates the fast detector simulation tool Delphes and processes the results through multiple modular components. Users can enter their hypothetical physics scenarios into CheckMATE without exploring complex programming requirements thanks to its structured framework design.

Key features of CheckMATE include:

• The ability to handle event files from different Monte Carlo generators in formats such as HepMC or HepEvt.
• Advanced detector simulations faithfully mimicking ATLAS and CMS detectors’ performance with parametrizations of object reconstruction efficiencies and kinematic smearing.
• A comprehensive analysis suite that includes most of the significant LHC search results, especially those related to supersymmetric models and other BSM physics scenarios.
• Implementation of a statistical evaluation routine based on the S prescription to compute observed confidence limits and actual exclusion likelihoods.

Validation and Results

Validation of CheckMATE has been performed rigorously by cross-referencing its outputs with standard test cases and known parameter scans such as the CMSSM/mSUGRA models. The analyses show excellent agreement with the published experimental results across various BSM models, supporting the reliability of the tool for exclusion or confirmation purposes. The paper highlights how the software's flexibility is demonstrated by accommodating potential systematic variations in signal acceptances and backgrounds.

Implications and Future Directions

Practically, CheckMATE represents a significant advancement for theorists needing to test new physical models against a rapidly growing repository of experimental data. Theoretically, it enhances exploration in parameter space, making BSM model validity assessments expedited and more accessible. Future development plans aim to integrate leading-edge Monte Carlo event generators directly into CheckMATE and incorporate more exhaustive LHC results to augment its analytic capacity. The tool’s adaptability positions it well to extend its relevance with direct connections to platforms like FeynRules and SARAH, further bridging the gap between theoretical constructs and empirical validation.

Conclusion

The development of CheckMATE underscores the symbiotic relationship between theoretical and experimental physics. As the LHC continues to probe deeper into the parameters of new physics, CheckMATE provides a crucial infrastructure that assists researchers in ensuring their hypotheses withstand empirical scrutiny. The authors highlight both the current achievements and the forward-looking vision for CheckMATE, setting a vital benchmark for the continued integration of computational tools in physics research.