{"paper":{"title":"Blue Straggler Stars in Berkeley 18: A Multiwavelength Study of Their Physical Properties and Dynamical Evolution","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"Alok Durgapal, A. Raj, D. Bisht, D. C. \\c{C}{\\i}nar, Geeta Rangwal, Ing-Guey Jiang, K. Belwal, M. Manu, M. S. Bisht, Shraddha Biswas","submitted_at":"2026-06-03T08:59:27Z","abstract_excerpt":"Berkeley~18 is an old open cluster in the outer Galactic disk that hosts a population of blue straggler stars (BSSs). We present a comprehensive multiwavelength analysis of its BSS population using \\textit{Gaia} DR3 astrometry, optical--infrared photometry, and time-domain TESS observations. Using a Gaussian Mixture Model (GMM) in astrometric space, we identify 798 high-probability cluster members ($p > 0.7$). Isochrone fitting yields an age of $3.2 \\pm 0.2$ Gyr and a heliocentric distance of $5.01^{+0.75}_{-0.55}$ kpc. We identify 24 BSS candidates above the main-sequence turn-off. Spectral e"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.04624","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2606.04624/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}