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arXiv · 2311.00030

Model Independent Reconstruction of Galaxy Stellar Velocity Map

Mikhail Denissenya·Eric V. Linder·Sangwoo Park·Arman Shafieloo·Satadru Bag
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Abstract

We develop a model independent, robust method for determining galaxy rotation velocities across a 2D array of spaxels from an integral field spectrograph. Simulations demonstrate the method is accurate down to lower spectral signal-to-noise than standard methods: 99\% accurate when median $S/N=4$. We apply it to MaNGA data to construct the galaxy velocity map and galaxy rotation curve. We also develop a highly efficient cubic smoothing approach that is $25\times$ faster computationally and only slightly less accurate. Such model independent methods could be useful in studying dark matter properties without assuming a galaxy model.

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Mikhail Denissenya, Eric V. Linder, Sangwoo Park, Arman Shafieloo, Satadru Bag. 2023-10-31. Model Independent Reconstruction of Galaxy Stellar Velocity Map. https://arxiv.org/abs/2311.00030

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