An Unsupervised Machine Learning Approach to Identify Spectral Energy Distribution Outliers: Application to the S-PLUS DR4 data

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Quispe-Huaynasi, F., Roig, F., Holanda, N., Loaiza-Tacuri, V., Eleutério, Romualdo, Pereira, C. B., Daflon, S., Placco, V. M., de Oliveira, R. Lopes, Sestito, F., Humire, P. K., Fernandes, M. Borges, Kanaan, A., Ribeiro, T., Schoenell, W.
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866909594562854912
author Quispe-Huaynasi, F.
Roig, F.
Holanda, N.
Loaiza-Tacuri, V.
Eleutério, Romualdo
Pereira, C. B.
Daflon, S.
Placco, V. M.
de Oliveira, R. Lopes
Sestito, F.
Humire, P. K.
Fernandes, M. Borges
Kanaan, A.
Ribeiro, T.
Schoenell, W.
author_facet Quispe-Huaynasi, F.
Roig, F.
Holanda, N.
Loaiza-Tacuri, V.
Eleutério, Romualdo
Pereira, C. B.
Daflon, S.
Placco, V. M.
de Oliveira, R. Lopes
Sestito, F.
Humire, P. K.
Fernandes, M. Borges
Kanaan, A.
Ribeiro, T.
Schoenell, W.
contents Identification of specific stellar populations using photometry for spectroscopic follow-up is a first step to confirm and better understand their nature. In this context, we present an unsupervised machine learning approach to identify candidates for spectroscopic follow-up using data from the Southern Photometric Local Universe Survey (S-PLUS). First, using an anomaly detection technique based on an autoencoder model, we select a large sample of objects ($\sim 19,000$) whose Spectral Energy Distribution (SED) is not well reconstructed by the model after training it on a well-behaved star sample. Then, we apply the t-distributed Stochastic Neighbor Embedding (t-SNE) algorithm to the 66 color measurements from S-PLUS, complemented by information from the SIMBAD database, to identify stellar populations. Our analysis reveals 69 carbon-rich star candidates that, based on their spatial and kinematic characteristics, may belong to the CH or Carbon-Enhanced Metal-Poor (CEMP) categories. Among these chemically peculiar candidates, we identify four as likely carbon dwarf stars. We show that it is feasible to identify three primary white dwarf (WD) populations: WDs with hydrogen-dominated atmospheres (DA), WDs with neutral helium-dominated atmospheres (DB), and the WDs main sequence binaries (WD + MS). Furthermore, by using eROSITA X-ray data, we also highlight the identification of candidates for very active low-mass stars. Finally, we identified a large number of binary systems using the autoencoder model, but did not observe a clear association between the overdensities in the t-SNE map and their orbital properties.
format Preprint
id arxiv_https___arxiv_org_abs_2504_18491
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle An Unsupervised Machine Learning Approach to Identify Spectral Energy Distribution Outliers: Application to the S-PLUS DR4 data
Quispe-Huaynasi, F.
Roig, F.
Holanda, N.
Loaiza-Tacuri, V.
Eleutério, Romualdo
Pereira, C. B.
Daflon, S.
Placco, V. M.
de Oliveira, R. Lopes
Sestito, F.
Humire, P. K.
Fernandes, M. Borges
Kanaan, A.
Ribeiro, T.
Schoenell, W.
Solar and Stellar Astrophysics
Astrophysics of Galaxies
Instrumentation and Methods for Astrophysics
Identification of specific stellar populations using photometry for spectroscopic follow-up is a first step to confirm and better understand their nature. In this context, we present an unsupervised machine learning approach to identify candidates for spectroscopic follow-up using data from the Southern Photometric Local Universe Survey (S-PLUS). First, using an anomaly detection technique based on an autoencoder model, we select a large sample of objects ($\sim 19,000$) whose Spectral Energy Distribution (SED) is not well reconstructed by the model after training it on a well-behaved star sample. Then, we apply the t-distributed Stochastic Neighbor Embedding (t-SNE) algorithm to the 66 color measurements from S-PLUS, complemented by information from the SIMBAD database, to identify stellar populations. Our analysis reveals 69 carbon-rich star candidates that, based on their spatial and kinematic characteristics, may belong to the CH or Carbon-Enhanced Metal-Poor (CEMP) categories. Among these chemically peculiar candidates, we identify four as likely carbon dwarf stars. We show that it is feasible to identify three primary white dwarf (WD) populations: WDs with hydrogen-dominated atmospheres (DA), WDs with neutral helium-dominated atmospheres (DB), and the WDs main sequence binaries (WD + MS). Furthermore, by using eROSITA X-ray data, we also highlight the identification of candidates for very active low-mass stars. Finally, we identified a large number of binary systems using the autoencoder model, but did not observe a clear association between the overdensities in the t-SNE map and their orbital properties.
title An Unsupervised Machine Learning Approach to Identify Spectral Energy Distribution Outliers: Application to the S-PLUS DR4 data
topic Solar and Stellar Astrophysics
Astrophysics of Galaxies
Instrumentation and Methods for Astrophysics
url https://arxiv.org/abs/2504.18491