Identification

Title

Asteroseismic constraints on diffusion in white dwarf envelopes

Abstract

The asteroseismic analysis of white dwarfs allows us to peer below their photospheres and determine their internal structure. At similar to 28 000K EC20058-5234 is the hottest known pulsating helium atmosphere white dwarf. As such, it constitutes an important link in the evolution of white dwarfs down the cooling track. It is also astrophysically interesting because it is at a temperature where white dwarfs are expected to cool mainly through the emission of plasmon neutrinos. In the present work, we perform an asteroseismic analysis of EC20058-5234 and place the results in the context of stellar evolution and time-dependent diffusion calculations. We use a parallel genetic algorithm complemented with targeted grid searches to find the models that fit the observed periods best. Comparing our results with similar modelling of EC20058-5234's cooler cousin CBS114, we find a helium envelope thickness consistent with time-dependent diffusion calculations and obtain a precise mode identification for EC20058-5234.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d7t1547m

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

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keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

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Temporal reference

Temporal extent

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End position

Dataset reference date

date type

publication

effective date

2011-06-01T00:00:00Z

Frequency of update

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version of format

Constraints related to access and use

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Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact