Peak Definition and 253 Threads

I'm trying to understand why peak resolution changed in my alpha spectroscopy experiment. I've increased the distance between a Am-241 source and a silicon surface barrier (semiconductor) detector and taken spectra along the way, recording information about peak height and FWHM. As the...

Handgun ammunition contains Ba and Sb compounds. Firing a handgun leaves residues of these elements in microgram quantities on the back of ones hand. Such quantities are 1000 times above the detection threshold for neutron activation analysis for Ba and Sb. Assuming a swab is taken from the back...

Hi, as I know the burst C rating usually refers to the max current allowed for 10 seconds. if I need higher current for 1 second, I can do it? The heat is the problem here?

Hi, guys. I'm beginning to fit XPS peaks from a environmental measurement but, as I'm unfamiliar with the exact process I have a lot of doubts. I have solved some of them using the info in http://xpssimplified.com/periodictable.php and in the XPS manual from Moulder and Stickle but I'm not...

Hi guys, I want to calculate the size of nanoparticles by using data from a peak list obtained from the use of XRD. Can anybody help me calculate the particle size by using the scherrer equation? Thanks! :)

Would there be destructive interference if I had two waves that are superimposed and the peak of one wave met the trough of the other but they both have different amplitudes? If there isn't total destructive interference, then what does the final wave look like?

Hi,I've been doing a lab cycle on X-ray crystallography. We are using Cu X-ray source on chloride salt crystals. It seems that the Bragg peak profile are commonly acknowledged to be a Voigt function, which is a convolution of Gaussian and Lorentzian. I am wondering what's the physical reason for...

This thread is prompted by a closed thread which left it’s OP’s original question unanswered. ->https://www.physicsforums.com/threads/average-wavelength-for-blackbody-radiation.423536/ The original question asked: is the ratio, of (a) the wavelength corresponding to the average energy in the...

Homework Statement Calculate the reciprocal lattice vectors for LiF. Given the lattice parameter ##a = 0.402 nm## calculate the magnitude of the ##\textbf{G_{220}}## reciprocal lattice vector for LiF and thus deduce the Bragg angle for the (2,2,0) Bragg peak for incoming wavelength of ##0.9...

Homework Statement A radio broadcast antenna is located at the top of a steep tall mountain. The antenna is broadcasting 104.3 FM (in Megahertz) with a power of 5.00 kilowatts. What is the peak intensity of the signal at a receiving antenna located 25.0 km away? Homework Equations Honestly...

I need to understand if Optical-gain peak, (Photoluminescence) PL peak and the Electroluminescence (EL) peak are they same or different. If they are the same/different what the corresponding conditions? Would be easier for me if bulk GaAs is used for the explanation (comparison at same...

I am new to peak deconvolution, I try to find information about this on the internet but just get a brief understanding of it. Can anyone provide me some suggestions or information about having a deeper understanding of this thing?

Can someone tell me that in bcc lattice why xrd 100 peak does not appear?

Hi there, I am currently studying charge transfer reactions between metallic electrodes and redox couples in aqueous electrolytes (in a diffusion limited system), and I was wondering about the influence of the rate constant on the reduction/oxidation peak maximum. Typically, it is assumed that...

Homework Statement If a question gives us a max load with different extensions, how do I calculate the strain? For example: 1900KN=x mm 1900KN=x mm 2000KN=x mm 2000KN=x mm 2000KN=x mm 1900KN=x mm 1900KN=x mm Homework Equations strain= ΔL / L The Attempt at a Solution What I think is...

Homework Statement The Planck blackbody spectrum is given by u(ω,t)=\frac{ħω^3}{π^2c^3(e^{βħω}-1)} Show that the peak of the Planck spectrum for a blackbody at a temperature T occurs at the wavelength λ_{max}T=0.29 where T is in Kelvin and λmax is in cm. Homework Equations...

I recently acquired a 39 gram sample of U-238 metal. I ran a gamma spectrum on the sample and found a major peak around 97 keV. I couldn't find any documents that mentioned this peak for U-238, but it is very prominent. I ran a gamma ray spectrum on a 5 gram Uranium Oxide sample and it also...

If we know the max. pressure (p) is 2.5 MPa and T = 20 C. Peak intensity, I = p^2 / rho * c where rho = density of water: 0.9982E03 kg/m^3 and c = speed of sound in water: 1482.3 m/s at 20 C I = (2.5E06 [Pa])^2 / 1.4796E06 [kg/m^2/s] = 4.2241E06 W/m^2 Is this correct?

Homework Statement https://session.masteringphysics.com/problemAsset/1385140/3/36.P42.jpg Part A What is the peak current supplied by the emf in the figure? Part B What is the peak voltage across the 4.0 μF capacitor? Homework Equations I = V/XC = E0/1/2πfC = 2πfCE0 The Attempt at a Solution...

If I am attempting to prevent a suspended motor-rotating imbalanced drum of high mass from colliding with its enclosure, how can I attempt to predict the maximum displacement from a balanced center of rotation if I have only a single sensor that can accurately measure(1000 samples/sec)...

Homework Statement The infrared spectrum of CO shows a vibrational absorption peak at 2170 cm-1 (a) What is the force constant of the CO bond? (b) At what wavenumber would the corresponding peak for 14CO occur? Homework Equations k=ω2μ = (2πcv)2μThe Attempt at a Solution So I solved part a...

When 2 black holes coalesce when is the peak energy created, when the BHs are close together or when they are fully merged.

This is a follow up to an old thread: https://www.physicsforums.com/threads/the-first-acoustic-peak-in-cmb.475412/. In the final draft of the Plank study - http://arxiv.org/pdf/1303.5076v3.pdf - they quote the sound horizon at 1.04147 x 10-2. This equates to a multipole moment of 302...

Homework Statement [/B] Hi there! This is a question from a practice problem sheet I got from the lecturer of my Condensed Matter 1 course. Below are the normal vectors to the {111} and {112} lattice planes: Homework Equations [/B] Bragg Condition: \begin{equation} n \lambda = d \sin...

Why almost every crystal system has peak around 32 degree (2 theta) ?

Homework Statement The peak intensity of light from the sun occurs at a wavelength 500nm. Astronomers discover a nearby star X which is the same size and mass as the sun, but has a peak wavelength of half this value. Is X hotter or colder than the sun and by how much?[/B]Homework Equations...

Hi all, I have been getting the emission spectrum of a polymer for a while. The emission peak is very important for that polymer. How do I find the emission peak of the polymer? The reason I ask this question is that if I simply select the highest point, then several points at different...

Can someone tell me how i can determine the one degree peak from power spectrum ?

Hello,i would like to ask something about the first peak in power spectrum of cmb giving by WMAP experiment.The y-axis is temprature difference between two points and the horizontal is the angle seperation.the first peak giving as the fundamental frequency of sound wave right? if we suppose that...

Homework Statement If the peak values of current through inductor (L), capacitor (C) and resistor (R) in parallel AC circuit are 2mA, 3mA, and 5mA respectively, then the peak value of current delivered by the source in the same circuit will be Homework EquationsThe Attempt at a Solution i (R)...

1. Homework Statement Homework Equations Hi all. Lets start with subquestion a). How do i calculate the PEAK gain? The Attempt at a Solution I drew the small signal equivalent and calculated the gain: Av=vo/vi=-gm(ro//R=1kΩ//L//C) Is that correct? How do i now calculate the peak gain...

Hello, I am doing my master thesis about "Means to improve the indicated efficiency in internal combustion engines",and this evening reading about Turbo-charging that doubt came up: talking in turbocharger terms,peak pressure and boost pressure are the same? Thank you in advance for your...

This came up in the arxivs and had me thinking can this be true? arXiv:1506.05478 [pdf, ps, other] Is the baryon acoustic oscillation peak a cosmological standard ruler? Boudewijn F. Roukema, Thomas Buchert, Hirokazu Fujii, Jan J. Ostrowski Comments: 4 pages, 2 figures Subjects: Cosmology and...

Homework Statement Homework Equations I have some equations relating B to I but I don't really know if they are useful The Attempt at a Solution I actually don't even know where to begin on this, my notes are confusing and vague :(

It's known that the nuclear reaction rate (inside a Star) can be determined with $$R_{ab}=n_a n_b\left<\sigma v\right> \, \approx \, n_a n_b \Big(\frac{8}{\pi m_e}\Big)^{1/2} \frac{S(E_0)}{(k_BT)^{3/2}} \Delta \frac{\sqrt{\pi}}{2} e^{-3E_0/k_BT},$$ where ##k_B## is Boltzmann constant, ##T##...

Hey guys I'm new here. I'm an ME student and I'm working on a project. I originally posted this on my350z forum and no one replied. Maybe it's too boring I don't know. If anyone has experience can you help me? Thanks. Hey guys, so I've been recently delving more and more into my z and wanting...

Could you please give proof for Imax formula of peak rectifier with capacitor ??

Homework Statement I am trying to find the peak time and %OS from the diagram Homework EquationsThe Attempt at a Solution I know how to get the %OS but for the peak time, isn't it just the time of the first peak, so around 1.1s? But the answer I am supposed to be getting is 0.0922s

Homework Statement (a) If R1 = 4.7kΩ, what value for C1 will give a cutoff frequency of 50kHz? (b) If the input voltage is described by the equation Vin = 3cos(2π(4000)t), what will the peak output voltage be?[/B] Homework Equations (a) fc = 1/(2πRC) (b) Vout/Vin = 1/√(1 + (2πfRC)2) The...

I'm looking at deep inelastic scattering of a low-energy inelastic electron scattering from a stationary proton target. I am given ##E## and ## \theta ## where ##\theta ## is the scaterring angle. ##E=4.879 GeV , \theta=10^{0} ## I am given a figure of cross section...

Homework Statement The peak of the thermal radiation power spectrum (dR/dλ) is at a wacelength of about λm=hc/5kT. Why is the peak of the same power spectrum plotted as dR/df not at fm=c/λm= 5kT/h? Homework Equations dR/dλ= 2πhc2/(λ5(e(hc/λkT)-1)) f=c/λ The Attempt at a Solution

I understand that the peak-width of diffraction data increases with increasing amounts of heterogeneous, localized (AKA "micro-") strain. So, if you have a single crystal with atomic impurities in it that each create micro-strain in the lattice, you would expect the amount of peak-broadening...

So I'm pretty sure I got 5-iodovanillin. The melting point in the literature is 183-185 C and I got 182.7-183.5 C. But my NMR spectrum isn't showing the alcohol peak. It barely shows up on the SDBS spectrum also (http://sdbs.db.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi). Does anybody know why...

Homework Statement A simple electric generator contains a 30-turn coil of area 6.6 x 10^-4 meters squared. The coil spins in a magnetic field of 0.80 T at a frequency of 60 Hz. a) What is the peak output voltage? b) How must the number of turns be changed to maintain the same output voltage...

As I understand, spectral emission peak can broaden due to high temperature of the emitter. For example, emission of "cold" CO2 will have a thin peak at 4.3um while the CO2 emitted from a (very hot) rocket plume will have a broad emission at ~4um - 4.7um (called "red/blue spike") What is the...

In an EM wave traveling west, the B field oscillates vertically and has a frequency of 80.0kHz and an rms strength of 7.75 × 10−9T. What is the peak strength of the Electric Field. So I worked this problem and got it wrong earlier and am looking for explanation as to why. To Solve this...

Homework Statement Here is the prompt: http://i.imgur.com/GsZck8J.jpg Homework Equations E(max) = NABw = 2pi*NABf The Attempt at a Solution E(max) = NABw = 2pi*NABf = NA*B(nought)*2pi*f 1.50 / (NA*B(nought)*2pi) = f f = 1.50 / N / ((2.50/100)^2*pi) / 0.109 / (2pi) The...

Homework Statement An RLC circuit has a sinusoidal voltage supplied to it at 632 kHz with a peak voltage of 748 kΩ; a 25 kΩ resistance; a 16 µF capacitance; and a 30 H inductance. What is the peak current for this circuit? A) 30 μA B) 26 μA C) 6.3 μA D) 11 μA...

Hello. So when you apply a square wave of voltage to a circuit, there is a slight delay for the electrical current. I'm trying to understand this concept better. I'd like to know if this delay is shorter with wire diameter.. if higher voltage decreases the delay time.. etc. Is there a name for...

Hello everyone! I am generating a signal as a function of time. This is an irregular signal generated by using the superposition principle and random phase. Thus I actually have already all the frequency components of the signal. And from the frequency components I know that there is also a...