Spectrum Definition and 725 Threads

Hello I have this Hamiltonian: \mathcal{H} = \alpha S_{+} + \alpha^{*}S_{-} + \beta S_{z} with \alpha, \beta \in \mathbb{C} . The Operators S_{\pm} are ladder-operators on the spin space that has the dimension 2s+1 and S_{z} is the z-operator on spin space. Do you know how to get (if...

Is it possible for EM radiation to exist outside the EM spectrum? I'm aware of the different frequencies at which energy can be radiated eg. radio, infrared, and gamma. But is it possible for objects to absorb or release energy at subradio or supergamma frequencies? Or is there a physical law...

Hey guys, I recently noticed that, after a swim, when you look at the light, you see a spectrum around it. The light was white light. And you see it with naked eyes. Can you guys explain this phenomenon? The water did contain Chlorine and maybe other necessary chemicals required in...

so the title speaks for itself i hope. my problem is i don't know how to work the formula. what are the ns about?? lamba^-1 = R(n1^-2 - n2^-2)

Dear All I am trying to measure the spectrum of an incandesant 6V 15W tungsten microscope lamp. I have a reasonably old scanning monochromator (diffraction grating based) coupled to a fibre optic cable and it has given me the spectrum...

This question might be better answered by someone in the mobile industry, but I guess I'll ask it here since it does involve physics. I understand that wireless spectrum for mobile data is finite, and will run out at some point. Out of curiosity, what are the implications of that exactly...

Homework Statement Let A be a linear transformation on the space of square summable sequences \ell2 such that (A\ell)n = \elln+1 + \elln-1 - 2\elln. Find the spectrum of A. 2. The attempt at a solution I see that A is self-adjoint, so its spectrum must be a subset of the real line. We also...

I was taking solar spectra yesterday for a Physics lab, and I found this strange phenomenon slightly to the left of the sun. I think it might be a solar prominence, but then again I know absolutely nothing about astronomy. What is it? (The graph is intensity vs. wavelength)...

hello i was just wondering what is considered to be the finger print region in an IR spectrum. Is there a range of wavenumbers which are designated as the finger print region? ...let me clarify um so a C-O bond in an ether (and maybe alcohol) is suppose to have a peak in the 1000-1200cm^-1...

Homework Statement (a)The cosmic microwave background fits the blackbody radiation spectrum well with a temperature of 2.7 K and a corresponding peak wavelength at 1.9nm. Applying the relationship between the radiant emittance, i.e. the total power emitted per unit area, and the photon energy...

Hi The new edition of th book " fast Breeder Reactors" by Reynolds has been revealed by the Springer publishing under the title of " Fast Spectrum Reactors". the book is downloadable in the following address for those who have access to Springer accounts...

Homework Statement I have attached the question and necessary infromationHomework Equations The Attempt at a Solution so here's what I would say "Unlikely as the peaks in the IR spec are very similar, no additional peaks have shown" BUT THE MARK SCHEME SAYS Vanillin IS likely to have...

dear all, after doing a complex Fourier series on a function. i am asked to find and graph the magnitude and phase spectrum of a function. now to cut the long story short. let's say we arrived a Fourier series like this. = \sum_{i=-∞}^{∞} \frac{1}{npi}sin...

I got this thing from wikipedia: http://img72.imageshack.us/img72/9878/vlszo.jpg Link to wikipedia: Visible spectrum So: - Is it the right scan of visible spectrum? Because when I search, there are a lots of other version, which is not really like each other. (Google Link) - What is the...

how can microwaves heat food?

Homework Statement X rays give continuous spectrum and line spectrum. Whether these spectrums are emission or absorption spectrum? Homework Equations The Attempt at a Solution I think it is emission spectrum, because there is no absorbing material. Still, i need confirmation from...

What determines the wave length.

I've recently taken a spectral image (visible wavelengths) of Jupiter. After calibrating my spectral analysis program I've been able to get wavelength per pixel and produce a graph of intensity vs wavelength. I have an absorption spectra of Jupiter, but I am unaware on how to correlate which...

Hello! I'm writing a thesis about the optical properties of CO2. However I'm having a hard time finding any solid material about the basic info of the absorption spectrum of CO2. I'm especially interested in the absorption band at approximately 4,3µm. If any of you guys know some good articles...

Hi there, just wondered if anyone could help me... If I am given a hamiltonian describing a particle in one dimension H=p^2/2m +1/2 (γ(x-a)^1/2) + K(x-b) how do I go about finding the eigenstates and eigenvalues of this hamiltonian? Many thanks

hi i was wondering why the spectrum of an ordinary light bulb is continuous. i know that "i think it's thermodynamics" says that some temperature creates a specific continuous radiation, but how is this reconcilable with quantum mechanics and e.g. a sodium gas, that emits only a tiny yellow...

[Solved] How and why does a prism split white light into the colour spectrum Homework Statement How and why does a prism split white light into the colour spectrum? Homework Equations Red light has a lower frequency than violet light. As speed of light = wavelength * frequency, red...

Hi, I've been trying to figure out how to convert a spectrum from wavelength space into velocity space. I thought it would be a simple relation, but I can't see it - maybe I'm missing something? I've got Flux v Wavelength at the moment, so I converted into frequency space. I've played...

Homework Statement A two-state system has Hamiltonian \sum |i\right\rangle hi \left\langle i| + Δ (| 1 \right\rangle \left\langle 2| + |2 \right\rangle \left\langle 1 |) Where, \left\langle i | j \right\rangle = \deltaij, hi, and Δ are real. Compute the energy spectrum of this...

I know that light is a form of electromagnetic radiation but I know that all electromagnetic radiation is not light. I know that light has four basic properties: 1) Light travels in straight lines. 2)Light can reflect. 3)Light...

A question I have puzzled over for a year now is how we define time. We chose light as the fastest thing we know (currently) as our mathematical limit, as only massless particles can only reach c our calulations of Gr and Sr are based on this. Unitl I started hearing terms of backwards in time...

Is it a silly question to ask *why* we see the orders of colors the way we do in the visible spectrum with respect to wavelength? For instance, I know that comparisons to dogs are often made with the following visible spectrum comparisons...

Assuming, of course, that we simply rescaled our color perspectives so that longest wavelengths = red, shortest wavelengths = violet. Are there any such pictures?

Radiation with a wavelength in the visible light range is what mainly reaches the Earth's surface. What is so special about visible light that makes it so easy to reach the surface compared to something like gamma rays with a smaller wavelength or something with a larger wavelength? Also...

I am in need of the wavelength of the spectral lines of sodium but all I can find is the wavelength for the doublet. I am looking for the cyan coloured one that appears very close to 500nm but I cannot find the exact value anywhere. Would anyone be able to direct me somewhere? Thanks

Hi there, So I am doing this lab write-up at the moment with a single channel analyser. The following diagram pretty much sums up the setup: So pretty much I have found a suitable operating voltage gain by recording number of counts vs. gain and now I must change the Baseline-E...

Continuous absorption spectrum -- why this happens? Homework Statement A pure green glass plate placed in the path of light, absorbs everything everything except green, similarly red glass plate absorbs everything except red. Homework Equations May i know the reason for this? Thanks...

Homework Statement While dealing with continuous absorption spectrum, my book depicts like this " A pure green glass plate when placed in the path of white light, absorbs everything except green and gives continuous absorption spectrum" Homework Equations The Attempt at a Solution...

In wikipedia I've read that the Sun's surface temperature is about 5700K. The emission spectrum graph can be seen there: http://en.wikipedia.org/wiki/File:EffectiveTemperature_300dpi_e.png. I don't understand why the irradiance (or intensity I guess) of the Sun is greater than the one of a...

In his article on the Zero-point Energy: http://www.calphysics.org/zpe.html Bernard Haisch says: That the spectrum of zero-point radiation has a frequency-cubed dependence is of great significance. That is the only kind of spectrum that has the property of being Lorentz invariant. The...

Homework Statement The outermost electron in a sodium atom can be in these energy states: (1)-0.82 aJ, (2) -0,48 aJ, (3) -0.31 aJ 1 aJ= 10^{-18} J. When we study the spectrum of a sodium lamp, we see a yellow line. Use the above given energy states to determine the wavelength of this yellow...

I mean how can i analysis the thermal conductivity of two structures with their phonon spectrum. thank you!

I have been posting on here pretty frequently; please forgive me. I have an exam coming up in functional analysis in a little over a week, and my professor is (conveniently) out of town. We proved in our class notes that if T:X\to X is a compact operator defined on a Banach space X, \lambda...

i and my friend want to have spectrum of star. i need star light with high intensity to diffract this. unfortunately, we don't know how we can have a intense light? do you know how we can do this? or in general, how can we have spectrum of light star?

hi everyone, i would be grateful for suggestions for the following problem: i have a set of measurements, discrete samples from a continuous function of time. with each measurement comes a estimate of its uncertainty (standard error). by doing a discrete Fourier transform, i have seen some...

What are the conditions for which it can be concluded that a system has discrete energy levels? For example a system in one dimension with the potential V(x)=b|x| has only a discrete spectrum. How I can prove it? My book says moreover that the energy eigenvalues have to satisfy the...

no of line in line spectrum is equal to jumps of electron from one shell to another. Am i correct. IN my book it is written that if a electron in hydrogen jumps from n1 to n2 then number of spectral lines is given by formula {(n1-n2)(n1-n2+1}/2. so consider a electron jump from 4th shell to 2nd...

Our eyes have 3 types of cones to perceive color, one for red, one for green, and one for blue. On the one end of the spectrum we see red. But on the other end of the spectrum we do not see blue, but beyond blue we have violet. How is this possible? :confused: A bit of research found...

Hello, does anyone know of a code that will generate the expected neutron spectrum for an AmBe neutron source along with the expected reaction efficiency?

Hey all, I am trying to locate an atomic spectrum for the following elements. O2 and N2 I have the information from 10nm - Visible, but the internet seems to be always missing the first piece of information that is vital to my experiment. Thanks for any assistance in locating. I have...

I posted this http://answers.yahoo.com/question/index;_ylt=AioiPKUALWyrKuH4dGXejba9DH1G;_ylv=3?qid=20110618143816AAgRMyF"on Yahoo Answers yesterday, but it might be too specialized: If I understand correctly, the Cosmic Microwave Background Radiation is a perfect thermal (black-body)...

Hi, I am new to QM, so advanced apologies for the dumb questions to follow. What does "the spectrum of boundstates is non-degenerate" mean? And why is the time-independent Schrodinger eqn reflection invariant? (I'm not sure I quite know what that means either...) Thanks!

Hi guys, this is a homework question, but i didnt think it belonged with the physics questions. I have the spectrum of a star, it has hydrogen gamma and hydrogen beta absorbtion lines, but a very very strong hydrogen alpha emission line. What is the significance of this, I would expect a...

If I modulate a pulse X(t) with a.) a sine wave or b.) a cosine wave, I have the frequency spectrum expressions a.) \frac{1}{2j}[X(f-f_0)-X(f+f_0)] b.) \frac{1}{2}[X(f-f_0)+X(f+f_0)] When I plot these for a pulse, I see a difference in the magnitude spectrum, but I should not expect...

Hi all, I'm working on Taylor's text on scattering (a reference from Peskin and Schroeder). They define the Moller operators \Omega which are isometric, satisfying \Omega^{\dagger}\Omega=1 This is not necessarily the same as unitary in an infinite dimensional space, the difference being...