Spectral energy distributions

When considering light of a certain spectral energy distribution falling on an object with a given spectral reflectance and perceived by an eye with its own spectral response, to obtain the perceived color stimulus it is necessary to multiply these factors together as ia Eigure 6. Standards are clearly required for both the observer and the illuminant. 

In Fig. 6, we report the radius an the mass of the compact star RX J1856.5-3754 inferred by Walter Lattimer (2002) (see also Kaplan et al. 2002) from the fit of the full spectral energy distribution for this isolated radio-quite neutron star , after a revised parallax determination (Kaplan et al. 2002) which implies a distance to the source of 117 12 pc. Comparing the mass-radius box for RX J1856.5-3754 reported in Fig. 6 with the theoretical determination of the MR relation for different equations of state, one concludes that RX J1856.5-3754 could be (see e.g. Fig. 2 in Walter Lattimer, 2002) either an hadronic star or an hybrid or strange star (see also Drake et al. 2002). 

Measurements of combustion temperatures, radiation intensity distributions in the range from 400 to 800 nm, and particle size distributions of combustion products have been made for the reaction of aluminum powder with both 02/Ar and H2O oxidizers in atmospheric dump combustors. The fraction of unburned aluminum in the combustion products was also determined for the H2O oxidizer case. An analytical study was performed to determine if the measurements are consistent with each other and with theory, and also to estimate the rate of heat loss from the combustion products. A Monte Carlo technique was used to determine the expected spectral energy distribution that would be emitted from a viewport located in the side of a combustion chamber containing products of aluminum combustion. 

Fig. 2. Spectral energy distribution of the emission of YFs-En (5%) 366 nm excitation (from Ref. (30))...

Figure 5. Spectral energy distributions of red-emitting cathode ray phosphors (8 ...

Figure 6. Spectral energy distributions of several green-emitting cathode ray...

Staton RD, Enderle JD, Gerst JW. The electroencephalographic pattern during electroconvulsive therapy. IV. Spectral energy distributions with methohexital, innovar and ketamine anesthesias. Clin Electroencephalogr 1986 17 203-215. 

Figure 12. Spectral energy distribution of daylight phase D65 with permitted range of deviation (shading)...

Observational evidence for the dynamic mass-flow phase includes (A) light-curves where the secondary eclipse becomes deeper at shorter wavelengths (Kondo et al. 1985), (B) the non-monotonic variation of the spectral energy distribution which is pronounced in the ultraviolet (Kondo et al. 1985), and (C) continued presence, both inside and outside the eclipses, of emission features observed in beta Lyrae (Hack et al. 1977). Phenomena (A) and (B) have been attributed to the presence of variable, optically-thick, extrastellar plasma. 

BLACK BODY. This term denotes an ideal body which would, if it existed, absorb all and reflect none of the radiation felling upon it its reflectivity would be zero and its absorptivity would be 100%. Such a body would, when illuminated, appear perfectly black, and would be invisible except its outline might be revealed by the obscuring of objects beyond. The chief interest attached to such a body lies in the character of the radiation emitted by it when heated and the laws that govern the relations of the flux density and the spectral energy distribution of that radiation with varying temperature. 

The total emission of radiant energy from a black body takes place at a rate expressed by the Stefan-Boltzmann (fourth-power) lav/ while its spectral energy distribution is described by Wien slaws, ormore accurately by Planck s equation, as well as by a n umber of oilier empirical laws and formulas, See also Thermal Radiation,... 

Figure 2. Spectral energy distribution of sunlight at the earth s surface for solar angles of 10°, 40°, and 90°, from direct sun (--) or reflection from open sky (--) (5 ). ...

The spectral energy distribution of CIE light sources A and C is shown in Figure 6-2. CIE illuminant A is an incandescent light operated at 2854°K, and illuminant C is the same light modified by filters to result in a... 

Figure 6-2 Spectral Energy Distribution of Light Sources A and C, the CIE, and Relative Luminosity Function y for the CIE Standard Observer...

Figure 6-3 Spectral Energy Distribution of Sunlight (S), CIE IUuminant (A), Cool White Fluorescent Lamp (B), and Sodium Light (N)...

The fundamental initial parameters of protoplanetary disk evolution are the masses and sizes of the disks. Optical silhouettes of disks in the Orion Nebula Cluster (McCaughrean O Dell 1996), scattered light imagery (e.g. Grady et al. 1999), interferometric maps in millimeter continuum or line emission (e.g. Rodmann et al. 2006 Dutrey et al. 2007), and disk spectral energy distributions... 

Expressing the size distributions in this way is analogous to the way a spectral energy distribution vFv presents equal energy radiated in equal logarithmic frequency bins. 

Since dust particles emit inefficiently at wavelengths much shorter than their size, it is necessary to observe at millimeter to centimeter wavelengths to probe particles that have experienced strong particle growth. The tracer of such large particles is the spectral slope ft of the emissivity of dust, defined as kv v at wavelengths > 500 pm. The disk spectral energy distribution (SED, see Chapter 3) is related to the opacity, rv = kvT (R) as ... 

Figure 9.1 Examples of spectral energy distributions from young Sun-like stars with circumstellar dust disks. Optically thick dust disks (solid line) have excess emission relative to the stellar photosphere over a broad wavelength range, from near-infrared to millimeter wavelengths. Transition disks (dashed line) lack near-infrared excess emission, but have large mid- and far-infrared emission. Debris disks (dotted line) have small excess emission starting at wavelengths typically longer than 10 pm. Primordial and transition disks often show a prominent 10 pm silicate emission feature from warm dust grains in the disk atmosphere.

The Infrared Spectrograph (IRS) provided crucial data to characterize the mid-infrared rise in the spectral energy distribution of transition disks, which bear... 

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