This repository contains the cluster_pipeline codes used to identify and characterize stellar structures in galaxies, including NGC 4449. The results were published in Meena et al. 2025, ApJ, 987, 33.
- Detect hierarchical stellar structures (clusters, associations, complexes).
- Compare structures as a function of stellar age or magnitude (mass proxy).
- Quantify structural properties using clustering + MST-based analysis.
- Identify hierarchical stellar structures using HDBSCAN clustering.
- Works with either:
- Stellar ages, or
- F275W photometry for magnitude-based selection.
- Outputs:
- Stellar Complexes (EOM clusters)
- Substructures (Leaf clusters)
- Calculate cluster areas, radii, and stellar separations.
- Perform Minimum Spanning Tree (MST) analysis to determine clustering parameters such as
m_bar,s_bar, andQ. - Produce violin plots showing distributions of these parameters as a function of age, magnitude cuts, or other selections.
- Target info file (tab-separated) with:
Galaxy_name Distance(Mpc) PA(deg) Inclination(deg) - RA, Dec, and ID for each source/star
- Identified clusters and subclusters (stellar complexes and substructures) for each age or magnitude group
- Saved as
.txtfiles along with summary outputs
- Stellar population maps with EOM and Leaf clusters
- Individual cluster plots with ellipse fitting and MST structure
- Violin plots of cluster parameters vs. age or magnitude
- The GULP project focuses on the most massive young stars, providing a short lookback time but enabling high-fidelity cluster detection.
- Input parameters for HDBSCAN (e.g., minimum cluster size) should be tuned using nearest-neighbor distributions or domain knowledge.
- The pipeline is modular and can be adapted for other galaxies or photometric datasets.
- Python 3.8+
numpy,pandas,matplotlib,seabornastropyhdbscan
- Clone the repository:
git clone https://github.com/yourusername/cluster_pipeline.git
cd cluster_pipeline