# Tag Info

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The wavefunction is always antisymmetric. It does not matter if they have similar, different, or even identical numbers for $n$ and $l$. But let's be clear. The wavefunction is a function from the configuration space into the joint spin state. So for a spin 1/2 particle the wavefunction is a function from $\mathbb R^3$ to $\mathbb C^2$ whereas for two spin ...

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In STM, you tunnel from states of your tip into states of the sample. Electrons can tunnel into states within the whole bulk and the matter beneath. However, their spectral weight decays rather quickly. As a rule of thumb in STM, your current increases by one order of magnitude per Angstroem that you reduced the tip-sample distance. So, the DOS of matter 1 ...

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I was looking through some NIST atomic data for the Balmer Series from here: http://www.nist.gov/srd/upload/jpcrd382009565p.pdf It lists the spontaneous emission rates for the Balmer series as follows: $\lambda = 656 \text{ nm}$, $A_{32} = 4.41\text{e+}7\text{ s}^{-1}$ $\lambda = 486 \text{ nm}$, $A_{42} = 8.42\text{e+}6\text{ s}^{-1}$ $\lambda = 434 ... 2 If you actually look at (atmospherically) scattered light, you will see that even at ground-level, there is a distinct blue tint. How do you see that, you ask? Any old shadow will do - find some building that throws a nice big shadow, make a photo with a decent camera, and analyze it thoroughly - you'll find that there's indeed a blue tint, as expected. Why ... 11 It's because you're not looking far enough. From personal experience, it takes at least 10 km of atmosphere to build up a really obvious blue (see, for example, this picture), and if you're not in hilly country, the horizon is only 5km away. In contrast, most of the sky has distances to space on the order of hundreds of kilometers. 3 Two reasons: The scattering separates red/orange and blue in different directions. At sunset you'll see the red parts that are missing from the blue skies by day. This isn't noticeable for objects close by, because those objects surround you. The blue from some objects mixes with the red from others. Secondly, there is a lot of air between you and the ... 29 If I understand you right, you're referring to the phenomenon seen in this picture (from the first Google hit), that near the horison the color of the sky is more light-blue (not exactly white): Rayleigh scattering The scattering in the atmosphere is for a large part Rayleigh scattering off of nitrogen and oxygen molecules, which are much smaller than ... 1 This is something I never really understood, but Glen Knoll Offers the following in pp. 116 of his book "Radiation Detection and Measurement": "The energy resolution of the detector is conventionally defied as the FWHM divided by the location of the peak centroid H_0 The energy resolution R is thus a dimensionless fraction conventionally expressed as a ... 0 Generally the higher the frequency the more will be absorbed in a given medium. 20Hz will go right through you, and you will feel it. However, if you are talking about ultrasonic imaging there is a tradeoff between resolution and wavelength (frequency). Shorter wavelengths (higher frequencies) will give you a better image but be absorbed more strongly. As ... 1 Positive dispersion means that the lower frequencies are ahead of the higher frequencies in time, and this is caused by the fact that the crystal's group index (derivative of refractive index) is smaller for lower frequencies, giving them faster group velocity going through the crystal. To compensate, the pair of prisms gets the higher frequencies to catch ... 2 Are you using the Apex-Gamma software? If so, a fitted singlet is a line the software has identified as being a single distinct line rather than a peak in a region where there are multiple overlapping lines. As I recall, Apex-Gamma identifies lines that are overlapping by$M$or$m\$ (presumably for multiplet).

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That means that the peaks could be fit with single Gaussian, the simplest fit. They did not have to fit as a doublet (two lines close together). Ortec has a technical paper on line at Deconvolution of Gamma-Ray Peak Doublets as a Function of Peak Separation and Relative Amplitude

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It depends on what you want how you choose the polarization of the light. The polarization of your light determines the recoil of your electron and your ion. In photoelectron vmi you would like to see the angular distribution of how the electron detaches from the molecule, so you should select the polarization of your light such that the velocity vector of ...

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There are several broadband light sources in outer space such as quasars and blazars which basically can act as a light bulb. Earth bound telescopes as well as satellite telescopes can see absorption features in the light when the light passes through some cloud in outer space that contains molecules before the light reaches earth. In addition molecules in ...

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