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Title: Asteroseismic Diagram for Subgiants and Red Giants

Abstract

Asteroseismology is a powerful tool for constraining stellar parameters. NASA’s Kepler mission is providing individual eigenfrequencies for a huge number of stars, including thousands of red giants. Besides the frequencies of acoustic modes, an important breakthrough of the Kepler mission is the detection of nonradial gravity-dominated mixed-mode oscillations in red giants. Unlike pure acoustic modes, mixed modes probe deeply into the interior of stars, allowing the stellar core properties and evolution of stars to be derived. In this work, using the gravity-mode period spacing and the large frequency separation, we construct the ΔΠ{sub 1}–Δ ν asteroseismic diagram from models of subgiants and red giants with various masses and metallicities. The relationship ΔΠ{sub 1}–Δ ν is able to constrain the ages and masses of the subgiants. Meanwhile, for red giants with masses above 1.5 M {sub ⊙}, the ΔΠ{sub 1}–Δ ν asteroseismic diagram can also work well to constrain the stellar age and mass. Additionally, we calculate the relative “isochrones” τ , which indicate similar evolution states especially for similar mass stars, on the ΔΠ{sub 1}–Δ ν diagram.

Authors:
;  [1];  [2];  [3]
  1. College of Physics and Electronic information, Dezhou University, Dezhou 253023 (China)
  2. College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 401331 (China)
  3. Shandong Provincial Key Laboratory of Biophysics, Dezhou University, Dezhou 253023 (China)
Publication Date:
OSTI Identifier:
22663937
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 836; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DETECTION; EIGENFREQUENCY; GRAVITATION; MASS; METALLICITY; OSCILLATION MODES; OSCILLATIONS; STAR EVOLUTION; STARS

Citation Formats

Gai, Ning, Tang, Yanke, Yu, Peng, and Dou, Xianghua, E-mail: ning_gai@163.com, E-mail: tyk450@163.com. Asteroseismic Diagram for Subgiants and Red Giants. United States: N. p., 2017. Web. doi:10.3847/1538-4357/836/1/3.
Gai, Ning, Tang, Yanke, Yu, Peng, & Dou, Xianghua, E-mail: ning_gai@163.com, E-mail: tyk450@163.com. Asteroseismic Diagram for Subgiants and Red Giants. United States. doi:10.3847/1538-4357/836/1/3.
Gai, Ning, Tang, Yanke, Yu, Peng, and Dou, Xianghua, E-mail: ning_gai@163.com, E-mail: tyk450@163.com. Fri . "Asteroseismic Diagram for Subgiants and Red Giants". United States. doi:10.3847/1538-4357/836/1/3.
@article{osti_22663937,
title = {Asteroseismic Diagram for Subgiants and Red Giants},
author = {Gai, Ning and Tang, Yanke and Yu, Peng and Dou, Xianghua, E-mail: ning_gai@163.com, E-mail: tyk450@163.com},
abstractNote = {Asteroseismology is a powerful tool for constraining stellar parameters. NASA’s Kepler mission is providing individual eigenfrequencies for a huge number of stars, including thousands of red giants. Besides the frequencies of acoustic modes, an important breakthrough of the Kepler mission is the detection of nonradial gravity-dominated mixed-mode oscillations in red giants. Unlike pure acoustic modes, mixed modes probe deeply into the interior of stars, allowing the stellar core properties and evolution of stars to be derived. In this work, using the gravity-mode period spacing and the large frequency separation, we construct the ΔΠ{sub 1}–Δ ν asteroseismic diagram from models of subgiants and red giants with various masses and metallicities. The relationship ΔΠ{sub 1}–Δ ν is able to constrain the ages and masses of the subgiants. Meanwhile, for red giants with masses above 1.5 M {sub ⊙}, the ΔΠ{sub 1}–Δ ν asteroseismic diagram can also work well to constrain the stellar age and mass. Additionally, we calculate the relative “isochrones” τ , which indicate similar evolution states especially for similar mass stars, on the ΔΠ{sub 1}–Δ ν diagram.},
doi = {10.3847/1538-4357/836/1/3},
journal = {Astrophysical Journal},
number = 1,
volume = 836,
place = {United States},
year = {Fri Feb 10 00:00:00 EST 2017},
month = {Fri Feb 10 00:00:00 EST 2017}
}
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