Spectroscopy Definition and 335 Threads

P119, Mukamel's book "Principles of Nonlinear Optical Spectroscopy" Eq.(5.21) in Liouville space $$ S^{(2)}(t_2,t_1)=\left(\frac{i}{\hbar}\right)^2 \left\langle \left\langle V\left|\mathscr{G}(t_2)\mathscr{V}\mathscr{G}(t_1)\mathscr{V}\right|\rho(-\infty) \right\rangle\right\rangle $$ in...

Does anyone have a link ro the research showing that our sun was formed from more than thirty nebulae, not one as would be expected?

Hello, I am quite interested in Raman spectroscopy. For the reason I would like to get deeper into it. So I searched some details about it, so I know, that each particle emits specific "rainbow" after it receives some amount of radiation from light in various wave lengths and similar situation...

Hello everyone , in my mcnp coding for finding neutron spectroscopy I used F2 tally across a surface. Is it correct or I should use f4 tally? Morever I need to transform the flux data into neutron fluence. How can I do that. Here I uploaded my code. Though my data from codes is way more...

Hello everyone, currently I am doing a neutron spectroscopy experiments. I am doing it with the MCNP code. I designed my Geometry there, but facing problems in data cards, is there anyone who can help me in this sector?

If we spectroscopically observe a cloud of hot gas, which is on the whole not very absorbent, and which is not illuminated by a source behind it, we observe emission lines. How does this type of spectrum form? I had thought that those lines are those in which there are transitions of atoms is...

I've recently been tasked with obtaining transit spectrum data for some fascinating celestial bodies, including Ceres, Enceladus, Ganymede, Io, and Titan. The goal is to compare their transit spectra with that of Earth. However, I'm facing a bit of a challenge when it comes to using the Github...

We know from molecular spectroscopy that incoming light on a molecule can change a molecule's rotational, vibrational and electronic energy levels. If the incoming light is, on the far-infrared and microwave region the molecule gets rotational energy.(microwave spectra) on the near-infrared...

In spectroscopy, the highest peaks in the absorption spectrum are those that are associated with the most probable energy transitions in a molecule. The most probable transitions are those in which the best superposition between the wave function of the vibronic level of the fundamental state...

I know that for the vibrational Raman spectrum, the energy levels are given by- E(n) = ℏω(n+1/2) - χℏω(n+1/2)^2 But I'm not getting what does it meant by the Raman lines are observed at given values of wavelengths and the fundamental vibrational frequency. I equated the E(0) with the energy...

I don't know whether it is an energy of a photon emitted by a deexciting molecule, or if it is an energy of laser's photons. Here is an example of such spectrum: For example, that value of wavenumber ##3000\, \mathrm {cm^{-1}}## is an energy of an emitted photon or a photon from laser? And that...

Hello! I saw many paper extracting the magnetic dipole and electric quadrupole moments of the nuclei by performing RF/microwave spectroscopy on the rotational levels of a molecule. However, I can't seem to find paper measuring higher order moments. For example, the magnetic octupole moment has...

Hello! I have a question about selection rules and electronic transitions of a diatomic molecule: I can't find a good explanation about that, and there's so much confusion about the right rules to use. I studied that on Bransden-Joachain's "Physics of atoms and molecules", but there (to whom...

Hello ! As I understand it, the different isotopes of the same atom have a slightly different spectroscopic absorption and emission where, for example, Deuterium absorbs slightly shorter wavelengths than Protium. My question is if two isotopes of different atoms, for example Tritium and Helium...

I did a prac where we tried to calculate the rydberg constant for hydrogen. We had a hydrogen lamp and we used a spectrometer that was hooked up to a photomultiplier tube to detect the wavelengths of light corresponding to the balmer series. In one section I need to write up a brief summary of...

I was studying a Michelson interferometer for infrared absorption in Fourier transform and I've found these two images (taken from https://pages.mtu.edu/~scarn/teaching/GE4250/ftir_lecture_slides.pdf ) representing an infrared monochromatic beam of light going into the interferometer and the...

Hello everyone. I'm trying to do a Kubelka Munk equation for paint samples and would like to do the calculation in Excel first before moving it over to a programming language outside of MATLAB. I have Spectroscopic scans of the samples and put them into a database where the K/S values have been...

Hello! I am reading about Fourier Transform MW spectroscopy in a FB cavity, which seems to be quite an old technique and I want to make sure I got it right. As far as I understand, this is very similar to normal NRM, i.e. one applies a MW ##\pi/2## pulse which puts the molecules in a linear...

Hello, I have a few uncertainties about this, Forgive the long questions, I appreciate your time. 1) Why is the maximum energy photon loses during Compton scattering about 0.238MeV (if maximum angle 180 achieved aka backscatter) irrespective of the incoming photon total energy? It seems...

Hello! I see that most experiments applying quantum computing techniques for high precision spectroscopy use a quadrupole trap. I don't know much about the experimental implementation of these kind of traps, so any help (or suggested paper) would be appreciated, but I was wondering how well can...

Hello, My question relates to gamma spectroscopy. I understand how the net peak area is calculated for any photopeak. Fortunately, gamma-spec software (e.g., Genie-2000 from Canberra) provides Net peak area and associated uncertainty (for Cs-137 661.7 keV peak, as an example). My question: are...

The figure is shown; the measurements were taken on two consecutive observing nights. The Ordinate is the flux normalized to continuum and the abscissa is the wavelength scale. You can see the "bumps" indicated by the arrows referring to some Starspot as the spot moves on the profile; assuming a...

I'm trying to plot the solar spectrum (Wavelength versus Flux) from a table of values I'm given. I'm given 3 columns; Solar Flux Arcturus Flux Wavelength Plotting Solar Flux versus Wavelength gives me a graph (below) that is very difficult to resolve. There are 21,000 data points as well. If...

Hello! Assuming we use a laser of frequency very close to resonance, in the Ramsey technique (say for 2 level atoms) the ##\pi/2## pulse would put the Bloch vector in the equatorial plane, along the y axis, then in the free region the vector will rotate around the z axis accumulating a phase of...

I am interested, in the context of my work, in the cross correlations between a spectroscopic probe (which gives a 3D distribution of galaxies with redshifts, which is also called spectroscopic Galaxy clustering, GCsp) and a photometric probe (which gives an angular distribution, that is to say...

Precision Microwave Spectroscopy of the Positronium n=2 Fine Structure A nice compact abstract, so I'll just quote it here: Positronium with its two light leptons is the dream of every theorist, that keeps the uncertainties small. The 0.61 MHz experimental uncertainty are the sum of 0.57 MHz...

Hi, everyone: I tried to find the PDF or djvu for this book. Unfortunately, it failed to get it. Could you please so kind send me a link if you have? Thanks.

Hello! Can someone point me towards some introductory levels readings on Rabi and Ramsey spectroscopy. It seems that most readings online are scientific papers, I would like something more basic (e.g. lecture notes). Thank you!

Greetings, how do - the velocity distribution of the solar wind at 1 AU - the velocity distribution of the solar wind in our line of sight look like? I have found the 400 Km/sec but no further information. Is it an average values? Is this radially on the sun the same? Links with graphs are...

I read the "J. Phys. Chem. B 2018, 122, 7616−7624" paper where they calculated the pair distribution function using wide-angle X-ray scattering and mentioned the term " The distances to the first coordination shell for low-, high-, and very-high-density amorphous ice (LDA, HDA, VHDA) were...

Hello! I have some data from a molecular spectroscopy experiment, containing vibrational and rotational spectra, and I want to fit the peaks with Voigt profiles (one for each peak) in order to obtain the centers of the peaks. Do you know any software suitable for this kind of fit? I usually use...

How do you differentiate between the three? I read that "Spectrometry deals with the measurement of a specific spectrum. There are four primary types of spectrometers: 1. Mass spectrometry 2. Neutron triple axis spectrometry 3. Ion-mobility spectrometry 4. Rutherford backscattering...

Summary: How can I know the effects of ions on my coating using Raman and XPS? Hi! So I'm working on my thesis regarding surface morphology of Zn doped HAp coating. Now, my goal is to know the effects of Zn ions on the surface morphology of my coating using raman and xps. Jowever, I do not...

Hi all, my name's Ethan and I'm an undergraduate physics student conducting research on work functions this summer. I've been trying to understand the graphs of N(E) or N'(E) vs. auger electron energy for several days now, but I can't find in the literature what exactly N(E) or N'(E) are. I've...

Raman spectroscopy involves Illuminating a target with a laser Beam. This produces Raleigh scattering. Does The releigh scattering have the same frequency as the laser beam? So use an optical filter to block the same frequency as the laser?

I am writing a review on snapshot spectral imaging techniques, and, being mainly interested in visible applications, I looked into spectral analysis with light field cameras, which have been rather popular in the previous years (see wikipedia): the main reference for these systems, at least for...

Can raman spectroscopy identify any substance or are there certain Substances raman spectroscopy cannot identify?

Hi everyone! I'm a chemistry student, this year i have to learn different types os spectroscopy. I have had troubles to catch up with this subject. Would you please gimme some advices about sources of information to learn about spectroscopy? I Would appreciate it!

Hello everyone, I need some confirmation on something: As far as I understood, the raman spectroscopy measures the inelastic scattering of a photon in a medium through the absorption or the emission of a phonon in the medium. The energy and the momentum is conserved...

I'm an undergraduate and there is a very good optical spectroscopy and nano-materials physics lab at my college. I have FULL access to all equipment and a professor in that field is offering me a ridiculous amount of co-research time during the school year. However, I'm really only interested...

Hello, Recently I had a problem in the analysis of a raw material called Propranolol HCl, when performing Raman identification for the specific batch the obtained spectrum does not generate signal and, consequently, identity of the material. By testing other techniques like infrared and NMR, I...

Homework Statement The figure below shows the hyperfine structure in the transition 6s $^2S_{1/2}$ - 8p $^2P_{3/2}$ in 115In (I = 9/2). The measurement is made using a narrow-band tunable laser and a collimated atomic beam; hence the Doppler width is greatly reduced. The 6 components shown have...

I need some good book(s) or other resources from where I can learn UV-Visible Spectroscopy. Besides explaining the mathematical and theoretical intricacies, it should also mention the practical aspects. If you have read any and found it good, please recommend it.

I'm trying to find a good database of absorption or reflection spectra in visible light for pigments. I've found a wonderful database in this article: http://e-conservation.org/issue-2/36-FORS-spectral-database#CSV It's almost exactly what I needed Except I don't understand the data The...

Astronomers can determine the presence various elements in a star through spectroscopy of the incoming light from that star. The characteristic spectral lines of each element are formed by electrons transitioning between the various orbital energy levels around the nucleus of their atom. But...

To obtain spectroscopy on a gas like hydrogen or helium, an electric arc is passed through a container of the material, and then the emitted light is viewed through a prism which breaks it up into its component wavelengths. There are sharp lines which are formed, caused by excitation of the...

I wanted to know how do you control for changes in refractive index when you get the UV-Vis spectrum of an aqueous solution in a double beam spectrometer? Is that something the equipment does automatically? Or something I have to do? Also, how do these changes in refractive index occur? Thanks...

Homework Statement The decay path of Na 22 and Strontium 90 Experimental Setup The beta particle electron from strontium 90 and positron from sodium 22 physical measurement is as shown. Experimental Result (verified) Strontium beta particle(electron) Count Rate vs Energy(rest energy...

I am a Physics undergraduate at the University of Texas at Arlington. I am currently taking an Astrophysics class in which my professor talked about the inclination angle of the orbital plane of the binary star system and how it is impossible to determine that angle. I was wondering why is it...