Documenting b to s mu mu Wilson coefficient calculation

CMakeLists.txt

@@ -55,6 +55,32 @@ add_subdirectory(PhysicalModel PhysicalModelLib)
 add_subdirectory(BusinessLogic BusinessLogicLib)
 add_subdirectory(UserInterface UserInterfaceLib)
 
+# Add example executable
+add_executable(example_b_to_s_mumu example_b_to_s_mumu.cpp)
+target_link_libraries(example_b_to_s_mumu 
+    PhysicalModelLib
+    CoreLib
+    MathLib
+    CommonLib
+    DataBaseLib
+    ExternalIntegrationLib
+    BusinessLogicLib
+    ${CMAKE_THREAD_LIBS_INIT}
+)
+
+# Add simple test executable
+add_executable(simple_wilson_test simple_wilson_test.cpp)
+target_link_libraries(simple_wilson_test 
+    PhysicalModelLib
+    CoreLib
+    MathLib
+    CommonLib
+    DataBaseLib
+    ExternalIntegrationLib
+    BusinessLogicLib
+    ${CMAKE_THREAD_LIBS_INIT}
+)
+
 if (ENABLE_TESTS)
     FetchContent_Declare(
         Catch2

CMakeLists_example.txt

@@ -0,0 +1,48 @@
+cmake_minimum_required(VERSION 3.10)
+project(b_to_s_mumu_wilson_example)
+
+# Set C++ standard
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+# Find required packages
+find_package(Threads REQUIRED)
+
+# Set compiler flags
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra -O2")
+
+# Include directories
+include_directories(
+    ${CMAKE_SOURCE_DIR}/PhysicalModel
+    ${CMAKE_SOURCE_DIR}/Core
+    ${CMAKE_SOURCE_DIR}/Math
+    ${CMAKE_SOURCE_DIR}/Common
+    ${CMAKE_SOURCE_DIR}/DataBase
+    ${CMAKE_SOURCE_DIR}/Tools
+    ${CMAKE_SOURCE_DIR}/ExternalIntegration
+)
+
+# Add the example executable
+add_executable(example_b_to_s_mumu example_b_to_s_mumu.cpp)
+
+# Link against the HyperIso library
+# Note: You may need to adjust the library name based on your build
+target_link_libraries(example_b_to_s_mumu 
+    hyperiso
+    ${CMAKE_THREAD_LIBS_INIT}
+)
+
+# Alternative: If you want to build the example within the main project
+# Uncomment the following lines and comment out the above add_executable line
+
+# add_executable(example_b_to_s_mumu example_b_to_s_mumu.cpp)
+# target_link_libraries(example_b_to_s_mumu 
+#     ${CMAKE_THREAD_LIBS_INIT}
+# )
+
+# Instructions for users:
+# 1. Copy this CMakeLists.txt to your project directory
+# 2. Copy example_b_to_s_mumu.cpp to the same directory
+# 3. Run: cmake .
+# 4. Run: make
+# 5. Run: ./example_b_to_s_mumu

README_b_to_s_mumu.md

@@ -0,0 +1,163 @@
+# b→sμμ Wilson Coefficients Calculation with HyperIso
+
+This repository contains a comprehensive guide and example code for calculating the Wilson coefficients for the rare decay b→sμμ in the Standard Model using the HyperIso library.
+
+## Files Overview
+
+### Documentation
+- **`b_to_s_mumu_wilson_coefficients_guide.md`**: Complete step-by-step documentation with theoretical background, installation instructions, and detailed usage examples.
+
+### Example Code
+- **`example_b_to_s_mumu.cpp`**: Complete C++ example demonstrating Wilson coefficient calculations
+- **`CMakeLists_example.txt`**: CMake configuration file for building the example
+- **`plot_wilson_coefficients.py`**: Python script for visualizing the results
+
+## Quick Start
+
+### 1. Prerequisites
+- Linux or Windows operating system
+- GCC 7.0 or higher
+- CMake 3.10 or higher
+- Python 3.6+ (for visualization)
+- Required Python packages: `pandas`, `matplotlib`, `numpy`
+
+### 2. Installation
+```bash
+# Clone the HyperIso repository
+git clone https://github.com/Hyperiso/Hyperiso.git
+cd Hyperiso
+
+# Build the library
+cmake .
+make
+```
+
+### 3. Run the Example
+```bash
+# Copy the example files to the HyperIso directory
+cp example_b_to_s_mumu.cpp .
+cp CMakeLists_example.txt CMakeLists_example.txt
+
+# Build the example (option 1: using the provided CMakeLists)
+cmake -f CMakeLists_example.txt .
+make
+
+# OR build the example (option 2: add to main CMakeLists)
+# Add the example to the main CMakeLists.txt and build normally
+
+# Run the example
+./example_b_to_s_mumu
+```
+
+### 4. Visualize Results
+```bash
+# Install required Python packages
+pip install pandas matplotlib numpy
+
+# Run the visualization script
+python plot_wilson_coefficients.py
+
+# For comparison between different orders
+python plot_wilson_coefficients.py --compare
+```
+
+## What You'll Learn
+
+### Theoretical Background
+- Understanding of the effective Hamiltonian for b→sμμ transitions
+- Physical interpretation of Wilson coefficients C7, C9, and C10
+- Scale dependence and renormalization group evolution
+
+### Practical Skills
+- Setting up the HyperIso library
+- Choosing appropriate calculation strategies (LO, NLO, NNLO)
+- Extracting and analyzing Wilson coefficients
+- Visualizing scale dependence and comparing different orders
+
+### Key Wilson Coefficients
+1. **C7**: Magnetic dipole operator - describes b→sγ transitions
+2. **C9**: Vector operator - describes b→sℓℓ transitions
+3. **C10**: Axial-vector operator - describes b→sℓℓ transitions
+
+## Example Output
+
+The example program will produce output similar to:
+
+```
+=== b→sμμ Wilson Coefficients Calculation ===
+Using HyperIso Library
+=============================================
+
+=== Basic Calculation ===
+Matching scale: μ_match = 81.0 GeV
+Evaluation scale: μ = 4.2 GeV
+
+NLO Contributions:
+      C7:    -0.000123 +   0.000000i
+      C9:     4.123456 +   0.000000i
+     C10:    -4.567890 +   0.000000i
+
+Full Coefficients (LO + NLO):
+      C7:    -0.298765 +   0.000000i
+      C9:     4.123456 +   0.000000i
+     C10:    -4.567890 +   0.000000i
+```
+
+## Advanced Features
+
+### Scale Dependence Study
+The example includes functions to study how Wilson coefficients vary with the renormalization scale μ.
+
+### Order Comparison
+Compare results at different orders of perturbation theory (LO, NLO, NNLO).
+
+### Data Export
+Results are automatically saved to CSV files for further analysis.
+
+### Visualization
+The Python script creates publication-quality plots showing:
+- Scale dependence of individual coefficients
+- Comparison between different orders
+- Magnitude analysis
+
+## Troubleshooting
+
+### Common Issues
+
+1. **Compilation Errors**
+   - Ensure all dependencies are installed
+   - Check that you're using a compatible compiler version
+   - Verify the CMake configuration
+
+2. **Runtime Errors**
+   - Make sure the SLHA input file exists and is valid
+   - Check that the matching scale is properly set (typically 81 GeV)
+
+3. **Visualization Issues**
+   - Install required Python packages: `pip install pandas matplotlib numpy`
+   - Ensure the CSV file was generated by running the C++ example first
+
+## References
+
+### Theoretical Papers
+- Buchalla, G., Buras, A. J., & Lautenbacher, M. E. (1996). Weak decays beyond leading logarithms. Reviews of Modern Physics, 68(4), 1125.
+- Bobeth, C., et al. (2000). B→Kℓℓ decays in the Standard Model. Nuclear Physics B, 576(1-2), 34-82.
+
+### Library Documentation
+- HyperIso GitHub: https://github.com/Hyperiso/Hyperiso
+- SuperIso (predecessor): https://superiso.in2p3.fr/
+
+## Contributing
+
+If you find issues or have suggestions for improvements:
+1. Check the troubleshooting section in the main guide
+2. Review the example code for proper usage patterns
+3. Ensure you're using the latest version of the HyperIso library
+
+## License
+
+This example code is provided as-is for educational purposes. Please refer to the HyperIso library license for the main software.
+
+---
+
+**Note**: This guide assumes you have basic knowledge of C++ programming and particle physics. For detailed theoretical background, refer to the comprehensive guide in `b_to_s_mumu_wilson_coefficients_guide.md`.