![]() The x-axis labeled “Wavelength (nanometers)” ranges from about 380 nanometers at the origin on the far left to about 710 nanometers on the far right. A label pointing to the y-axis reads, “Brightness (might be labeled as intensity, counts, flux, power, absorbance, transmittance, or reflectance).” There are no numbers or tick marks on the y-axis. The y-axis is labeled “Brightness” with an arrow pointing up to indicate that brightness increases from bottom to top. The picture and graph are aligned vertically so that the relationship is clear. Graph of a Spectrumĭirectly below the picture of the spectrum is a graph of the same spectrum showing brightness on the vertical y-axis versus wavelength on the horizontal x-axis. The spacing between these lines increases from left to right. There is a series of prominent, thick black lines. The rainbow is not continuous from left to right, but is instead broken up with vertical black lines of varying width. Picture of a SpectrumĪ long horizontal rectangle has a rainbow coloring from blue on the far left to red on the far right. A graph of a spectrum can reveal differences in brightness and wavelength that are too subtle for human eyes to detect.Ī color illustration of a star’s spectrum with a brightness versus wavelength graph of the same spectrum aligned directly below. However, in order to study a spectrum in detail-to really see the subtle differences in brightness of different colors-it needs to be plotted on a graph. (Rainbows are spectra that appear naturally when sunlight passes through water droplets, which act like prisms.) Spectroscopes and spectrographs are scientific tools designed specifically for capturing and measuring spectra.Ī spectrum can be displayed as an image. You can do this using a glass prism, a device called a diffraction grating, or a combination of the two, known as a grism. The first step in spectroscopy is separating light into its component colors to make a spectrum. Rainbows are spectra that form naturally when sunlight refracts and spreads out as it passes through water droplets. Visualizing Spectra Rainbow over Waimea Canyon State Park, Hawaii. We can therefore use spectra-the detailed patterns of colors-to figure out things like exactly how hot something is and exactly what elements and compounds it is made of, without ever sampling it directly. The mechanism of the latter can be attributed to electron–phonon coupling as confirmed by a model of the temperature-dependence of the lifetime.The basic premise of spectroscopy is that different materials emit and interact with different wavelengths (colors) of light in different ways, depending on properties like temperature and composition. A dramatic decrease in the lifetime of the emission peak tentatively assigned to the most stable site with temperature is explained by a competition between the radiative and non-radiative decay paths of the 6 s6 p 3 P 1 state. They are found to be different from each other with indications of a mixture of short- and long- lived 6 s6 p 3 P J fine-structure components and demonstrate distinct temperature dependencies. Time correlated single photon spectroscopy is used to determine the lifetimes of the individual emission bands. Their tentative associations with observed absorption and emission features are discussed. Modeling of the ground-state site structure and stability predicts three Yb/Xe occupation types, substitutional ( ss), tetravacancy ( tv) and hexavacancy ( hv), in order of decreasing stability. Multiple emission peaks are observed and the effects of annealing and prolonged irradiation on their amplitudes are found to be significant and are interpreted as a consequence of Yb population transfer from one type of site to another. Emission induced by the 6 s 2 1 S 0 → 6 s6 p 1 P 1 excitation is found to be concentrated entirely in the region of the 6 s6 p 3 P J→ 6 s 2 1 S 0 decay, whereas the singlet emission is completely quenched. Both bands indicate that Yb atoms occupy multiple trapping sites, of which three are identified. Absorption bands are detected in the regions of the gas-phase 6 s 2 1 S 0 → 4 f 135 d 6 s 2 and 6 s 2 1 S 0 → 6 s6 p 1 P 1 transitions. The electronic transitions of ytterbium atoms in a solid Xe matrix grown at 4.8 K are investigated. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |