GMF_models_data_analysis_visualisation

Tools to compare Galactic Magnetic Field (GMF) models with C-BASS 5 GHz polarization data.
Includes end-to-end pipelines for loading observational maps, harmonizing synchrotron templates, masking, fitting, and generating comparison plots.

📄 Related material

• DESY 2025 GMF–C-BASS talk (slides)
• Paper in preparation: Shaw et al., Fall 2025
• Contact V. Shaw for relevant details at vasundhara.shaw@manchester.ac.uk as the work is still in progress

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🚀 Features

• Load & process polarization maps (C-BASS, S-PASS, Franken)
• Compute PI from Q/U with variance handling and RM masking
• Load & scale GMF synchrotron templates: JF12, UF23, SVT22, KST24, XH19, LogSpiral
• Frequency scaling across bands (e.g. 30 GHz → 4.76 GHz)
• Apply Galactic masks (GC, quadrants, N/S, high-latitude)
• Fit models via amplitude scaling and Spearman correlation
• Generate heatmaps, T–T plots, and region-wise tables

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📦 Requirements

This project requires Python 3.10+ and the following libraries:

Package	Recommended Version
numpy	1.23+
scipy	1.10+
pandas	2.0+
healpy	1.16+
matplotlib	3.7+
seaborn	0.12+
astropy	5.3+
scikit-image	0.21+
cmcrameri	1.7+
colorcet	3.0+

⚠️ Ensure your numpy/scipy versions are compatible with healpy and astropy.
Using a virtual environment (conda or venv) is highly recommended.

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⚙️ Installation

Clone the repository and set up a virtual environment:

git clone https://github.com/<your-username>/GMF_models_data_analysis_visualisation.git
cd GMF_models_data_analysis_visualisation

conda create -n gmf python=3.10
conda activate gmf

pip install numpy==1.23.5 scipy==1.10 pandas==2.0 healpy==1.16.5 matplotlib==3.7 \
            seaborn==0.12 astropy==5.3 scikit-image==0.21 cmcrameri==1.7 colorcet==3.0


## 📊 Example Outputs

- **Polarized intensity maps**: C-BASS/S-PASS data vs GMF model templates  
- **Heatmaps**: best-fit amplitudes & Spearman correlation across sky regions  
- **T–T scatter plots**: model vs. data comparisons in quadrants, GC, N/S, high-latitude masks  
- **Tables**: CSVs of fitted amplitudes, correlation coefficients, and regional statistics  

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## 📚 References

### GMF Models
- **SVT22** – Shaw et al., *Synchrotron emission in Galactic Magnetic Fields*, MNRAS 517, 2534 (2023)  
- **UF23** – Unger & Farrar (2023), *arXiv:2311.12120*  
- **KST24** – Kim, Seta & Thomson (2024), *arXiv:2407.02148*  
- **JF12** – Jansson & Farrar (2012), *ApJ 757, 14*  
- **XH19** – Han et al. (2019), *MNRAS 486, 4275*  
- **LogSpiral** – Page et al. (2007), *ApJ 665, 1067*  

### Observational Data
- **C-BASS** – C-Band All-Sky Survey  
- **S-PASS** – Carretti et al. 2019, *MNRAS 484, 4933*  

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## 📜 Citation

If you use this repository, please cite:

- Shaw et al., *C-BASS collaboration paper* (in preparation, Fall 2025).  
- [DESY 2025 GMF–C-BASS talk (slides)](https://drive.google.com/file/d/15HRuauIdqdiJdtrGDF_ruxOOCKgCX-uO/view).  

And, where appropriate, cite the GMF model papers listed in the [References](#-references) section.