普通の電波パルサーのX線スペクトルの吸収特性は,
Oleg Kargaltsev1, Martin Durant, Zdenka Misanovic
1Department of Astronomy, 222 Bryant Space Science Center, University of Florida, Gainesville, FL 32611, USA. kargaltsev@astro.ufl.edu
Science (New York, N.Y.)
|August 28, 2012
まとめ
研究者らは,典型的な回転動力パルサー (J1740+1000) のX線スペクトルで吸収特性を検出しました. この発見は,スペクトル線が以前考えられていたよりも中性子星でより一般的かもしれないことを示唆しています.
科学分野:
- 天体物理学 天体物理学
- 高エネルギー天体物理学
- 中性子星物理学 中性子星物理学
背景:
- ほとんどの非収束中性子星 (NSs) は,電波および/またはガンマ線を発射するパルサーです.
- 彼らのスペクトルは通常,スペクトルラインが欠けている連続体放射によってモデル化されます.
- 以前,スペクトル特性は,ユニークな特性に関連したいくつかのエキゾチックなNSでのみ観察されていました.
研究 の 目的:
- 普通の回転動力パルサーのスペクトル特性の存在を調査する.
- スペクトル線が,これまで考えられていたよりも,中性子星のより一般的な特徴であるかどうかを判断する.
主な方法:
- 回転動力を持つ電波パルサーJ1740+1000のX線スペクトロスコピー.
- 吸収特性を特定するためにスペクトルデータの分析.
主要な成果:
- J1740+1000のX線スペクトルにおける有意な吸収特性の検出.
- この発見は,パルサースペクトルのこれまでの理解に挑戦しています.
結論:
- スペクトルの特徴は,エキゾチックな中性子星に特有するものではなく,普通のパルサーにも存在する可能性があります.
- J1740+1000での吸収線の検出は,これらの特徴が中性子星の集団でより広く広がっていることを示唆しています.
- これはパルサーと他のタイプの中性子星の間のスペクトルギャップを埋めます.
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