Maybe you could help me with solving this problem.
The four-momenta in the initial state have the following form:
$$p_1=(x_1\cdot\frac{\sqrt{s}}{2},0,0,x_1\cdot\frac{\sqrt{s}}{2})
p_2=(x_2\cdot\frac{\sqrt{s}}{2},0,0,-x_2\cdot\frac{\sqrt{s}}{2})$$
The routine that generates the final state...
Thank you for your response! Regarding the points you mentioned:
1) it is a proton-proton collision at 1TeV center of mass energy. Histograms are on matrix element level the process is in LO and I used the same pdf set for both calculations
2) Yes, x may take all the values from 0 to 1 and...
Thanks! So I will have to look into this again. I was just wondering since I calculated the cross sections before with both programs and the results matched. Do you have any idea why that could be?
The process is u b < d t. Without using pdfs the distributions were basically the same Bit now with pdfs they are not anymore. I used mad analysis and a self written program (blue). Mine works in principle since I tested it without the pdfs
I attatched an example plot where I created the histogram for the differential distribution with respect to the energy of the d-quark produced in the scattering process. My conception is that the phase space generator can "decide" how much of the available energy it assigns to the respective...
Does anyone have experience with such strange behavior in Monte-Carlo methods? I think it is a conceptional problem and I am just missing a key point in how to set up the integration instead of a error in my code itself. I use data files from LHAPDF and also checked that my variables give the...
Thanks for your answer! I thought in this case the Riemann tensor should vanish as well due to it´s definition in form of products and derivatives of Christoffel symbols but one will probably simply use the argument that tensors are independent of any basis.
Hello everyone,
in equation 3.86 of this online version of Carroll´s lecture notes on general relativity (https://ned.ipac.caltech.edu/level5/March01/Carroll3/Carroll3.html) the covariant derviative of the Riemann tensor is simply given by the partial derivative, the terms carrying the...
Thanks for your replies! I actually took the info for the uncertainties from the webseite you linked. However I did not understand the following equations:
var(w_i * 1 event) = w_i^2 * var(1 event) = w_i^2
Do you know why the these three expressions are equal? In the first relation why why is it...
Here is the histogram you asked for. I am just not firm with the application of the poisson distribution since everyone says it kind of always applies in counting experiments but I still don't know why that is.
A second thing that I am unsure about is if the error from the MC ist poissonian I...
Hello everyone,
I calculated the matrix element of a parton level process and determined the total cross section via a MC-simulation. Then I wanted to look at some differential distributions like the differential cross section with respect to the energy of one of the particles in the final...