コンパクトなバイナリ星であるSS Cygniまでの正確な幾何学的な距離は,蓄積円盤理論を正当化している
J C A Miller-Jones1, G R Sivakoff, C Knigge
1International Centre for Radio Astronomy Research, Curtin University, Perth, WA 6845, Australia. james.miller-jones@curtin.edu.au
まとめ
精密な距離測定により,SS Cygniはこれまで考えられていたよりも近くにあることが明らかになりました. この発見は,矮星新星に対する蓄積円盤理論に対する大きな課題を解決する.
科学分野:
- * 天体物理学
- * 恒星の進化について
- * 蓄積物理学の学問
背景:
- * 矮星新星は白矮星が赤矮星から物質を吸収する二重星系である.
- *それらの爆発はディスク不安定モデルによって説明される.
- * 矮星新星SS Cygniは,以前に推定された光度により,このモデルに異議を唱える.
研究 の 目的:
- *SS Cygniまでの距離を正確に測定するために.
- * SS Cygniの観測された振る舞いを,蓄積円盤理論と調和させるため.
- * コンパクトな物体における蓄積の理解における不一致を解明するため.
主な方法:
- * 非常長期ベースライン干渉計 (VLBI) の無線観測を用いた.
- * 距離の決定にモデル独立のアプローチを使用しました.
- * 精密なパララックス測定が組み込まれています.
主要な成果:
- *SS Cygniまでの新しい正確な距離を114 ± 2パーセクで決定しました.
- *この改訂された距離は,以前のハッブル宇宙望遠鏡の推定159 ± 12パーセクより大幅に近い.
- *新しい距離は,SS Cygniの爆発の光度パラドックスを解明する.
結論:
- * SS Cygniへの改訂された距離は,その振る舞いをディスク不安定モデルと一致させる.
- * この研究は,コンパクトな物体に対する蓄積円盤理論の妥当性を強化しています.
- * 精密な距離測定は,天体物理現象を理解するために不可欠です.
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