Refined data on electron structure from invariant frequency ratios in electron and positron geonium spectra

2005 ◽  
pp. 75-76
Author(s):  
Hans Dehmelt
Keyword(s):  
Electron Structure ◽  
Frequency Ratios

Ti L-Spectrum XANES and Electron Structure of the System Ti-Al-C

1997 ◽  
Vol 7 (C2) ◽  
pp. C2-281-C2-282 ◽  
Author(s):  
V. V. Ilyasov ◽  
I. Ya. Nikiforov ◽  
Yu. V. Ilyasov
Keyword(s):  
Electron Structure

Exploring the X-ray universe via timing: mass of the active galactic nucleus black hole XMMUJ134736.6+173403

2019 ◽  
Vol 15 (S356) ◽  
pp. 348-350
Author(s):  
Eva Šrámková ◽  
K. Goluchová ◽  
G. Török ◽  
Marek A. Abramowicz ◽  
Z. Stuchlík ◽  
...  
Keyword(s):  
Black Hole ◽  
Frequency Ratio ◽  
Active Galactic Nucleus ◽  
Periodic Modulation ◽  
X Ray ◽  
Upper Limit ◽  
M 10 ◽  
Frequency Ratios ◽  
Quasiperiodic Oscillations ◽  
Twin Peak

AbstractA strong quasi-periodic modulation has recently been revealed in the X-ray flux of the X-ray source XMMUJ134736.6+173403. The two observed twin-peak quasiperiodic oscillations (QPOs) exhibit a 3:1 frequency ratio and strongly support the evidence for the presence of an active galactic nucleus black hole (AGN BH). It has been suggested that detections of twin-peak QPOs with commensurable frequency ratios and scaling of their periods with BH mass could provide the basis for a method intended to determine the mass of BH sources, such as AGNs. Assuming the orbital origin of QPOs, we calculate the upper and lower limit on the AGN BH mass M, reaching M ≍ 107–109M⊙. Compared to mass estimates of other sources, XMMUJ134736.6+173403 appears to be the most massive source with commensurable QPO frequencies, and its mass represents the current observational upper limit on the AGN BH mass obtained from the QPO observations.

Cents versus scale steps: Can we tell the difference between major and minor thirds?

2021 ◽  
pp. 030573562098727
Author(s):  
Pedro Neto ◽  
Patricia M Vanzella
Keyword(s):  
Auditory Processing ◽  
Perceptual Quality ◽  
Chromatic Scale ◽  
Major Scale ◽  
Accurate Performance ◽  
The Difference ◽  
Scale Step ◽  
Frequency Ratios ◽  
Tonal Context

We report an experiment in which participants ( N = 368) were asked to differentiate between major and minor thirds. These intervals could either be formed by diatonic tones from the C major scale (tonal condition) or by a subset of tones from the chromatic scale (atonal condition). We hypothesized that in the tonal condition intervals would be perceived as a function of scale step distances, which we defined as the number of diatonic leaps between two notes of a given music scale. In the atonal condition, we hypothesized that intervals would be perceived as a function of cents. If our hypotheses were supported, we should verify a less accurate performance in the tonal condition, where scale step distances are the same between major and minor thirds. The data corroborated our hypotheses, and we suggest that acoustic measurements of intervallic distances (i.e., frequency ratios and cents) are not optimal when it comes to describing the perceptual quality of intervals in a tonal context. Finally, our research points to the possibility that, in comparison with previous models, scale steps and cents might better capture the notion of global versus local instances of auditory processing.

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