K luminosities

In this international system of units, the seven fundamental units are established length = meter (m), mass = kilogram (kg), time = second (s), electrical current = ampere (A), temperature = degree Kelvin (°K), luminosity = candelas (cd), and the quantity of matter = mole (mole). Many traditional units, such as calories (cal) or kilocalories (kcal) and centimeters (cm), are stUl in common use among chemists. 

The differential K luminosity function for the total number of sources found in NGC1333-S shows a rising source count to 14th magnitude beyond whidi, the source count decreases to zero at 17 (due to our limiting E magnitude). 

Based on the colors of the giant branches at various K luminosities, the ordering of the metallidties we have adapted for the observed clusters is correct, but NGC 6528 may be somewhat more metal rich than -0.23 dex in [Fe/H]. 

The near infrared range is very sensitive to evolved objects (red dwarfs, late giant stars, spiral galaxies) and is much less affected by interstellar extinction than the optical range. The K luminosity is also an excellent tracer of the mass of galaxies. Infrared wide field observations are thus destined to... 

Photo flash Compositions. Workers at PicArsn have investigated a series of mixts of K perchlorate with powd metals for use as photoflash compns. Info on candlepower, time to peak luminosity, and duration of flash, as well as performance at sea level and 1 x 10s feet, are given for each compn (Ref 23). A standard mil photo flash compn is given as 40% atomized Al, 30% Ba nitrate, and 30% K perchlorate (Ref 22, P 274)... 

Consider the amount of radiation arriving on the surface of the Earth at a distance of 1 AU or 1.5 x 1011 m. The total flux of the Sun is distributed evenly over a sphere of radius at the distance of the planet, d. From the luminosity calculation of the Sun, F, the solar flux at the surface of Earth, FEarth, is F/47t(1.5 x 1011)2 = 1370 Wm-2 from the least-square law of radiation discussed in Example 2.4 (Equation 2.4). Substituting this into Equation 7.6 with the estimate of the albedo listed in Table 7.2 gives a surface temperature for Earth of 256 K. 

AU from the Sun, just outside the orbit of Mars, whereas the inner boundary is determined by the runaway-greenhouse effect as observed on Venus. If the surface temperature were too hot, above 373 K, this would vaporise all water on the surface of the planet. The inner boundary is around 0.85 AU so the habitable zone spans 0.85-1.7 AU for our Sun (Figure 7.7) but the current habitable zone spans 0.85 - 1.3 AU (t — 0) in Figure 7.7. The habitable zone was much larger when the Sun s luminosity was greater, and narrower when the luminosity was smaller. 

Calculate the distance spanned by the habitable zone around the Sun at its current luminosity of 3.8 x 1026 W. Using Equation 7.5 for the flux at a distance corresponding to 273 K, the freezing point of water is given by ... 

Pollux, one of the twins, has a surface temperature of 9000 K and a stellar radius of 1.16 Rsun- Calculate the reduction in luminosity from the surface of the star when a Jupiter-sized planet passes in front of the star. Is this likely to be detectable ... 

Luminosity or gravity from H-line strengths in hotter stars, Balmer jump and molecular features in F-K stars. 

Planetary nebulae are often even more rich in carbon than cool carbon stars, and those classified by M. Peimbert as Type I are rich in nitrogen, indicating effects of hot-bottom burning in intermediate-mass progenitor stars. The s-process elements are not normally detectable in PN or their central stars, but a remarkable case is that of FG Sagittae, the central star of a fossil planetary nebula, which has cooled in the course of the twentieth century from around 25 000 K to around 5000 K at constant bolometric luminosity. This star suddenly showed an enhancement of s-process elements in its atmosphere between 1965 and 1972 (see Jeffrey Schoenberner 2006, and references therein). 

Fig. 8.39. Chemo-spectrophotometric evolution of the solar neighbourhood (left) and the whole Milky Way (right) as a function of time. Panels aA show the oxygen and iron abundances, bB the mass of stars and gas and the star formation rate, cC the extinction in B, V and K bands along a line of sight normal to the plane, dD the luminosity in solar units (taking extinction into account), eE the colour indices and fF the supernova rates. Note that panels aA are in linear units (see Fig. 8.16), while the others are all logarithmic. After Boissier and Prantzos (1999).

Figure 24.5 Variation in mean temperature Tmean (1), mean mole fraction X112O (2), RMS temperature at the driving frequency fo Trms (3), and luminosity L (4), with relative phase of fuel and air, 6 tuei in the forced 5-kilowatt combustor. Normalization values Tmean = 1740, AH2O = 0.105, and Trms = 60 K. Steady parameters = 0.75, fo = 100 Hz, Aair = 25 W, and Atuei = 1.1 W. Vertical dotted lines correspond to relative phase values which yield Trms values greater than...

The luminosity then decreased rapidly from 20 to 0.5 Lq, where Lq is the Sun s present luminosity, whilst the surface temperature stabilised at around 4460 K. The Sun looked like an orange. The convective zone was resorbed and covered the star like a blanket. Although just 1% of the mass, it occupies today 30% of the radius ... 

When large spherical AP particles dg = 3 mm) are added, large flamelets are formed in the dark zone.Pl Close inspection of the AP particles at the burning surface reveals that a transparent bluish flame of low luminosity is formed above each AP particle. These are ammonia/perchloric acid flames, the products of which are oxidizer-rich, as are also observed for AP composite propellants at low pressures, as shown in Fig. 7.5. The bluish flame is generated a short distance from the AP particle and has a temperature of up to 1300 K. Surrounding the bluish flame, a yellowish luminous flame stream is formed. This yellowish flame is produced by in-terdiffusion of the gaseous decomposition products of the AP and the double-base matrix. Since the decomposition gas of the base matrix is fuel-rich and the temperature in the dark zone is about 1500 K, the interdiffusion of the products of the AP and the matrix shifts the relative amounts towards the stoichiometric ratio, resulting in increased reaction rate and flame temperature. The flame structure of an AP-CMDB propellant is illustrated in Fig. 8.1. 

Poulter on luminosity) 305-06(Detn of temp by radiation and spectra methods) 384 (Discussion on work done at PicArsn on radiation of pyrotechnic compns) 386 (Effect of radiation from a shock wave in an atmosphere at ordinary pressure is negligible in comparison to an endothermic reaction capable of absorbing thousands of kcal per kg of air at 10000°K) 396 (Discussion on energy loss by radiation from the body of the gas mainly in the form "Bremsstrahlung produced when electrons are deflected by ions) 398, 400, 401 403 (More discussion on radiation) 14) Cook (1958), 97, 150-53, 155 158 15) M.A. Cook et al,... 

Equation (6) is used to calibrate the apparatus and determine the detonation temperature Baum et al (Ref 44, p 97) described the spectroscope method developed in Russia in 1945 by Alentsev, Belyaev, Sobolev Stepanov, which was applicable only to transparent liquid expls, such as NG, NGc, etc. In order to elimi-. nate luminosity caused by shock wave in the atmosphere, the authors immersed the test tube with. sample in water. For a more detailed description of the method, see Ref 16 and pp 98-100 of Ref 44. The values obtd by this method are considerably lower than the calcd values. For example, for NG the exptl value was only 3150CK vs 4520°K obtd by calcn and for NGc. 3160 vs 4700... 

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