منابع مشابه
Analysis of the irregular pulsations of AC Herculis
The AAVSO lightcurve data of the irregularly pulsating star AC Herculis of the RV Tau class are analysed. The lightcurve is shown not to be compatible with a periodic, or even multiperiodic pulsation, even if allowance ismade for evolution. Instead the best explanation is that the irregularly alternating cycles are a manifestation of low dimensional chaos. Our flow reconstruction suggests that ...
متن کاملOptical noninvasive monitoring of skin blood pulsations.
Time-resolved detection and analysis of skin backscattered optical signals (remission photoplethysmography or PPG) provide rich information on skin blood volume pulsations and can serve for reliable cardiovascular assessment. Single- and multiple-channel PPG concepts are discussed. Simultaneous data flow from several locations on the human body allows us to study heartbeat pulse-wave propagatio...
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در این پایان نامه، درهمتنیدگی بین یک سیستم نقطه کوانتومی دوگانه(مولکول نقطه کوانتومی) و میدان مورد مطالعه قرار گرفته است. از آنتروپی ون نیومن به عنوان ابزاری برای بررسی درهمتنیدگی بین اتم و میدان استفاده شده و تاثیر پارامترهای مختلف، نظیر تونل زنی(که توسط تغییر ولتاژ ایجاد می شود)، شدت میدان و نسبت دو گسیل خودبخودی بر رفتار درجه درهمتنیدگی سیستم بررسی شده اشت.با تغییر هر یک از این پارامترها، در...
15 صفحه اولOn the optical pulsations from the Geminga pulsar
We present a model for generation mechanisms of the optical pulsations recently detected from the Geminga pulsar. We argue that this is just a synchrotron radiation emitted along open magnetic field lines at altitudes of a few light cylinder radii (which requires that Geminga is an almost aligned rotator), where charged particles acquire non-zero pitch-angles as a result of the cyclotron absorp...
متن کاملA Search for Optical Pulsations from Two Young Southern Pulsars
We report on high-speed optical photometry of the radio positions of two young rotation-powered pulsars. No pulsations were detected from the optical counterpart proposed by Caraveo et al. (1994) for PSR B1509–58, with a 2σ upper limit on the pulsed fraction of < 12%, significantly lower than that measured in the five known optical pulsars. Given its low pulsed fraction, high optical luminosity...
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ژورنال
عنوان ژورنال: Nature Physical Science
سال: 1973
ISSN: 0300-8746,2058-1106
DOI: 10.1038/physci244137a0