The Polluted Atmosphere of the White Dwarf NLTT 25792 and the Diversity of Circumstellar Environments

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F13%3A00399742" target="_blank" >RIV/67985815:_____/13:00399742 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1088/0004-637X/779/1/70" target="_blank" >http://dx.doi.org/10.1088/0004-637X/779/1/70</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/0004-637X/779/1/70" target="_blank" >10.1088/0004-637X/779/1/70</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The Polluted Atmosphere of the White Dwarf NLTT 25792 and the Diversity of Circumstellar Environments

Popis výsledku v původním jazyce

We present an analysis of X-shooter spectra of the polluted, hydrogen-rich white dwarf NLTT 25792. The spectra show strong lines of calcium (Ca H&K, near-infrared calcium triplet, and Ca I?4226) and numerous lines of iron along with magnesium and aluminum lines from which we draw the abundance pattern. Moreover, the photospheric Ca H&K lines are possibly blended with a circumstellar component shifted by ?20 km s?1 relative to the photosphere. A comparison with a sample of four white dwarfs with similarparameters show considerable variations in their abundance patterns, particularly in the calcium to magnesium abundance ratio that varies by a factor of five within this sample. The observed variations, even after accounting for diffusion effects, implysimilar variations in the putative accretion source. Also, we find that silicon and sodium are significantly underabundant in the atmosphere of NLTT 25792, a fact that may offer some clues on the nature of the accretion source.

Název v anglickém jazyce

The Polluted Atmosphere of the White Dwarf NLTT 25792 and the Diversity of Circumstellar Environments

Popis výsledku anglicky

We present an analysis of X-shooter spectra of the polluted, hydrogen-rich white dwarf NLTT 25792. The spectra show strong lines of calcium (Ca H&K, near-infrared calcium triplet, and Ca I?4226) and numerous lines of iron along with magnesium and aluminum lines from which we draw the abundance pattern. Moreover, the photospheric Ca H&K lines are possibly blended with a circumstellar component shifted by ?20 km s?1 relative to the photosphere. A comparison with a sample of four white dwarfs with similarparameters show considerable variations in their abundance patterns, particularly in the calcium to magnesium abundance ratio that varies by a factor of five within this sample. The observed variations, even after accounting for diffusion effects, implysimilar variations in the putative accretion source. Also, we find that silicon and sodium are significantly underabundant in the atmosphere of NLTT 25792, a fact that may offer some clues on the nature of the accretion source.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BN - Astronomie a nebeská mechanika, astrofyzika

OECD FORD obor

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Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2013

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Astrophysical Journal

ISSN

0004-637X

e-ISSN

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Svazek periodika

779

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

10

Strana od-do

"70/1"-"70/10"

Kód UT WoS článku

000328160100070

EID výsledku v databázi Scopus

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