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The bolometric correction scale is set by the absolute magnitude of the Sun and an adopted (arbitrary) absolute bolometric magnitude for the Sun.Hence, while the absolute magnitude of the Sun in different filters is a physical and not arbitrary quantity, the absolute bolometric magnitude of the Sun is arbitrary, and so the zero-point of the bolometric correction scale that follows from it.
The star has 97% of the mass of the Sun and 100% of the Sun's radius. [11] It is of apparent magnitude 3.44, [ 2 ] radiating 129% [ 3 ] of the luminosity of the Sun from its outer envelope at an effective temperature of 6,010 K . [ 11 ]
The Greek astronomer Hipparchus established a numerical scale to describe the brightness of each star appearing in the sky. The brightest stars in the sky were assigned an apparent magnitude m = 1, and the dimmest stars visible to the naked eye are assigned m = 6. [7] The difference between them corresponds to a factor of 100 in brightness.
For example, a magnitude 2.0 star is 2.512 times as bright as a magnitude 3.0 star, 6.31 times as magnitude 4.0, and 100 times magnitude 7.0. The brightest astronomical objects have negative apparent magnitudes: for example, Venus at −4.2 or Sirius at −1.46.
The true stellar density near the Sun is estimated as 0.004 stars per cubic light year, or 0.14 stars pc −3. When combined with estimates of the stellar masses, this yields a mass density estimate of 4 × 10 −24 g/cm 3 or 0.059 solar masses per cubic parsec.
The average absolute magnitude of an RR Lyrae star is about +0.75, only 40 or 50 times brighter than the Sun. [8] Their period is shorter, typically less than one day, sometimes ranging down to seven hours. Some RRab stars, including RR Lyrae itself, exhibit the Blazhko effect in which there is a conspicuous phase and amplitude modulation. [9]
The mathematics for the creation and annihilation operators for bosons is the same as for the ladder operators of the quantum harmonic oscillator. [4] For example, the commutator of the creation and annihilation operators that are associated with the same boson state equals one, while all other commutators vanish.
RR Lyrae is a variable star in the Lyra constellation, figuring in its west near to Cygnus. [10] As the brightest star in its class, [11] it became the eponym for the RR Lyrae variable class of stars [3] and it has been extensively studied by astronomers. [7] RR Lyrae variables serve as important standard candles that are used to measure ...