716Hzで回転するラジオパルサー
Jason W T Hessels1, Scott M Ransom, Ingrid H Stairs
1Department of Physics, McGill University, Montreal, QC H3A 2T8, Canada. hessels@physics.mcgill.ca
まとめ
天文学者は,テルザン5球状星団の716ヘルツの二重電波パルサーを遮るものを発見しました. この発見は,これまでで最も速く回転する中性子星を明らかにし,恒星の進化と最大回転速度の既存のモデルに挑戦しています.
科学分野:
- 天文学と天体物理学について
- コンパクトなオブジェクト コンパクトなオブジェクト
- 中性子星とは,中性子星のことです.
背景:
- 中性子星は,極度の密度と急速な回転で知られている巨大な星の残骸です.
- パルサーは回転する中性子星で,電磁放射線を放射します.
- 球状星団は,恒星の密集した集合体であり,しばしばエキゾチックな恒星集団を宿している.
研究 の 目的:
- 急速に回転する中性子星を発見し,特徴づけること.
- 中性子星の最大回転速度の理論を検証する.
- 密度の高い恒星環境におけるパルサーの性質を調査する.
主な方法:
- グリーン・バンク望遠鏡を使ってラジオ観測.
- パルサーの周期的な放射能を介してパルサーを検出する.
- 軌道パラメータと流動密度を分析して,二重星系を遮る.
主要な成果:
- 球状星群テルザン5にある716ヘルツの二重電波パルサーを覆う二重電波パルサーの発見.
- このパルサーは,記録されている中性子星の中で最も速く回転し,以前の記録を上回っています.
- 低流量密度と高い日食分数は,さらに速いパルサーの存在を示唆しています.
結論:
- このパルサーの急速な回転率は,中性子星の回転を制限するモデルに挑戦しています.
- その性質は,中性子星の半径と質量に関する理論に制約を与える.
- この発見は,球状星団でより極端な天体を発見する可能性を強調しています.
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