Towards a public analysis database for LHC new physics searches using MadAnalysis 5

Abstract: We present the implementation, in the MadAnalysis 5 framework, of several ATLAS and CMS searches for supersymmetry in data recorded during the first run of the LHC. We provide extensive details on the validation of our implementations and propose to create a public analysis database within this framework.

• The paper introduces a public analysis database that integrates LHC new physics searches using the MadAnalysis 5 framework for comprehensive simulation and validation.
• It employs an event simulation approach that overcomes simplifications and provides versatile outputs for limit setting and efficiency mapping.
• The implementation is validated through detailed cut-flows and a Python CLs utility, promoting transparency and community contributions in collider phenomenology.

Analysis Database for LHC New Physics Searches with MadAnalysis 5

The paper discusses the establishment of a public analysis database for LHC new physics searches using the MadAnalysis 5 framework. It details the implementation of various ATLAS and CMS searches for supersymmetry based on data from the first LHC run. The overarching goal is to facilitate broader accessibility and usability of experimental analyses by the high-energy physics community.

Key Features of the Database

The database aims to offer a user-friendly platform for collider phenomenology, allowing researchers to access and extend LHC analyses using MadAnalysis 5. The proposal is complementary to existing tools such as SModelS, Fastlim, and CheckMATE, with distinct advantages:

1. Event Simulation Approach: By simulating events, the database circumvents the limitations of the Simplified Models approach.
2. Output Versatility: Provides event numbers in different experimental regions, enabling users to perform tasks like limit setting and efficiency mapping.
3. Open Source Initiative: Encourages contributions from the research community, emphasizing transparency and collective development.

Implementations and Validation

The paper presents the implementation of several analyses within the MadAnalysis 5 framework, validated against official results:

• CMS-SUS-13-011: A search for stop quarks in single lepton final states, focusing on decay modes $\tilde{t} \to t \tilde{\chi}^{0}_1$ and $\tilde{t} \to b \tilde{\chi}^{+}_1$. Validation against detailed cut-flows from CMS shows reasonable agreement, indicating accurate reproduction of the analysis.
• CMS-SUS-13-012: Searches for gluinos and squarks via jet multiplicity and missing energy. The agreement in cut-flow tables and kinematic variables like $n_j$, $H_T$, and $\slashed{H}_T$ illustrates robust implementation.
• CMS-SUS-13-016: Focuses on gluino searches in events with opposite-sign leptons and multiple jets. The validation emphasizes the importance of detailed systematic checks and reinforces the reliability of the implemented analysis.
• ATLAS-SUSY-2013-05/11: Searches for third-generation squarks, neutralinos, and charginos, validated through a series of benchmark points, highlight the importance of comprehensive SLHA inputs and precise MC configurations for accurate simulation and analysis reproduction.

Statistical Interpretation and Limit Setting

The paper also provides a Python utility for calculating exclusions using the $\mathrm{CL}_s$ method. This lightweight tool, integrated with MadAnalysis 5, facilitates quick evaluations of simulation results against LHC data. It identifies the most sensitive signal regions and computes exclusion values, thereby helping researchers assess the viability of theoretical models.

Implications and Recommendations

The proposed public analysis database has significant implications both practically and theoretically. Practically, it democratizes access to LHC analyses, allowing researchers without experimental collaborations' resources to test and validate hypotheses. Theoretically, the database could streamline new physics searches by making existing analyses more accessible and interoperable.

The paper suggests guidelines for both experimental collaborations and potential contributors. For collaborations, it stresses the need for detailed, unambiguous documentation and comprehensive validation material, including SLHA files and MC settings. For contributors, it emphasizes adherence to validation protocols and encourages publication of implementations via platforms like Inspire to ensure traceability and citation.

Overall, this proposed public analysis database is positioned as a valuable asset within the high-energy physics community, promising to enhance the collaborative search for new physics at the LHC and beyond.