{
  "id": "2411.13011",
  "version": "v1",
  "published": "2024-11-20T03:29:10.000Z",
  "updated": "2024-11-20T03:29:10.000Z",
  "title": "The temporal and spatial variations of lithium abundance in the Galactic disc",
  "authors": [
    "Tiancheng Sun",
    "Shaolan Bi",
    "Xunzhou Chen",
    "Yuxi",
    "Lu",
    "Yuqin Chen",
    "Ming-Yi Ding",
    "Jianrong Shi",
    "Hongliang Yan",
    "Zhishuai Ge"
  ],
  "comment": "Accepted for publication in MNRAS. 9 pages, 10 figures",
  "categories": [
    "astro-ph.GA",
    "astro-ph.SR"
  ],
  "abstract": "This study investigates the temporal and spatial variations in lithium abundance within the Milky Way using a sample of 22,034 main-sequence turn-off (MSTO) stars and subgiants, characterised by precise stellar ages, 3D NLTE (non-local thermodynamic equilibrium) lithium abundances, and birth radii. Our results reveal a complex variation in lithium abundance with stellar age: a gradual increase from 14 Gyr to 6 Gyr, followed by a decline between 6 Gyr and 4.5 Gyr, and a rapid increase thereafter. We find that young Li-rich stars (ages $<$ 4 Gyr, A(Li) $>$ 2.7 dex) predominantly originate from the outer disc. By binning the sample according to guiding center radius and z$_{\\rm max}$, we observe that these young Li-rich stars migrate radially to the local and inner discs. In addition, the stars originating from the inner disc experienced a rapid Li enrichment process between 8 Gyr and 6 Gyr. Our analysis suggests that the age range of Li-dip stars is 4-5 Gyr, encompassing evolution stages from MSTO stars to subgiants. The Galactic radial profile of A(Li) (with respect to birth radius), as a function of age, reveals three distinct periods: 14-6 Gyr ago, 6-4 Gyr ago, and 4-1 Gyr ago. Initially, the lithium abundance gradient is positive, indicating increasing Li abundance with birth radius. During the second period, it transitions to a negative and broken gradient, mainly affected by Li-dip stars. In the final period, the gradient reverts to a positive trend.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2024-11-20T03:29:10.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "lithium abundance",
      "spatial variations",
      "galactic disc",
      "birth radius",
      "rapid li enrichment process"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 9,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}