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تسجيل مستخدم جديدملاحظات الطيف البصري للمؤشر المتوسط EX Hydrae في الإستقرار
Spectroscopic Observations of the Intermediate Polar EX Hydrae in Quiescence
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نقدم هنا نتائج الملاحظات الطيفية للموجب المتوسط (IP) EX Hya في الإستقرار خلال عامي 1991 و 2001. تم الكشف عن سرعات نحوية معدلة بالدوران تتوافق مع مصدر قرص خارجي لأول مرة في IP. تم تعديل الدوران الإشعاعي مع سرعات تقريبا بالقرب من ~500-600 كم / س. هذه السرعات تتوافق مع تلك المواد التي تدور عند حافة القرص المؤخرج، مما يشير إلى تطابق الدوران مع الستار المؤخرج في مسافة بالقرب من حجم روش. بالإضافة إلى ذلك، أظهرت رسوم التوموغرام الدوبلر الدورانية دليلاً على وجود إشعاع الستار المؤخرج الذي يمتد من سرعات تقريبا ~500 كم / س إلى ~1000 كم / س. هذه النتائج أكدت النماذج النظرية التي تنبأت بها King & Wynn (1999)، Belle et al. (2002) و Norton et al. (2004) ل EX Hya، التي تنبأ بوجود ستارات مؤخرج كبيرة تمتد إلى مسافة بالقرب من حجم روش في هذا النظام. تم الكشف عن دليل على وجود جريان تجاوز يسقط على المغناطيسية، مؤكداً نتيجة Belle et al. (2005) بأن التجاوز القرص في EX Hya موجود أثناء الإستقرار والإخراج. يبدو أن سرعات الدوران النحوية لهبتا وهجاما ناتجة عن دوران القمع في حافة القرص الخارجية، في حين أن سرعات الهالفا ناتجة عن تدفق المواد على أسطح الأساليب المغناطيسية بعيداً عن الأسد البيضاء (المكون الضيق) وقريباً من الأسد البيضاء (المكون القاعدي الواسع)، موافقاً لنموذج الستار المؤخرج.
Results from spectroscopic observations of the Intermediate Polar (IP) EX Hya in quiescence during 1991 and 2001 are presented. Spin-modulated radial velocities consistent with an outer disc origin were detected for the first time in an IP. The spin pulsation was modulated with velocities near ~500-600 km/s. These velocities are consistent with those of material circulating at the outer edge of the accretion disc, suggesting corotation of the accretion curtain with material near the Roche lobe radius. Furthermore, spin Doppler tomograms have revealed evidence of the accretion curtain emission extending from velocities of ~500 km/s to ~1000 km/s. These findings have confirmed the theoretical model predictions of King & Wynn (1999), Belle et al. (2002) and Norton et al. (2004) for EX Hya, which predict large accretion curtains that extend to a distance close to the Roche lobe radius in this system. Evidence for overflow stream of material falling onto the magnetosphere was observed, confirming the result of Belle et al. (2005) that disc overflow in EX Hya is present during quiescence as well as outburst. It appears that the hbeta and hgamma spin radial velocities originated from the rotation of the funnel at the outer disc edge, while those of halpha were produced due to the flow of material along the field lines far from the white dwarf (narrow component) and close to the white dwarf (broad-base component), in agreement with the accretion curtain model.
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We use the best available X-ray data from the intermediate polar EX Hydrae to study the cooling-flow model often applied to interpret the X-ray spectra of these accreting magnetic white dwarf binaries. First, we resolve a long-standing discrepancy be
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