Hello community!
I am facing a conceptual problem with the correlation matrix between maximum likelihood estimators.
I estimate two parameters (their names are SigmaBin0 and qqzz_norm_0) from a multidimensional likelihood function, actually the number of parameters are larger than the two I am...
Hello everybody!
I am working on a code in which I need to study the dependence of ##<p_T>## vs ##p_L## (the average transverse momentum and the longitudinal momentum of a particle). I am looking for references, papers, books, etc. concerning this topic, but I have not been so lucky. My...
Hello everybody!
I have a doubt about a reaction.
$$ p + n \rightarrow \Lambda + \Sigma^+ $$
I have to establish if it is allowed or not.
Charge is conserved (1 -> 1)
Baryon number is conserved (2 -> 2)
Strangeness is not conserved (0 -> -2)
Third component of the isospin is not conserved (0...
Thank you for the reply. The attached diagram is better? The previous diagram is ##\mathcal{O}(\alpha_s^2)##, instead this one is ##\mathcal{O}(\alpha_s)##, isn't it?
PS It is not homework, I was just discussing about Feynman diagrams with a mate of mine.
Hello everybody!
I have to write the Feynman diagrams for the process ##\pi^- + p \rightarrow \Lambda_c^+ + D^-##. It is a strong process since all the quantum numbers are conserved.
I have attached my attempt, is it correct?
Thank you all in advance!
Hello everybody!
Let's begin with the spin. Spin of the ##\Lambda## is ##1/2## and of the pion is ##0##:
$$ \frac{1}{2} \otimes 0 = \frac{1}{2}$$
Since I know from the homework statement that ##L=1##:
$$ \textbf{J} = \textbf{spin} \otimes \textbf{L} = \frac{1}{2} \otimes 1 = \frac{1}{2} \oplus...
Hello everybody!
I join the conversation since I also have some doubts about Wu experiment.
Yes, you are right, but if the emission is in the opposite direction of the spin the weak interactions obey V-A structure, otherwise V+A... So, the direction of the emission is important.
From the...
$$|\rho^0> = |1,0> = \frac{1}{\sqrt{2}}|1,+1>|1,-1> + 0 |1,0>|1,0> - \frac{1}{\sqrt{2}}|1,-1>|1,+1> = $$ $$ =2\frac{1}{\sqrt{2}}|1,+1>|1,-1> + 0 |1,0>|1,0> = \frac{1}{\sqrt{2}}|\pi^+\pi^-> + 0 |\pi^0\pi^0>$$
From the Clebsch-Gordan coefficients I see that the decay in ##\pi^0\pi^0## is...
Hello everybody!
I have a question regarding the forbidden decay ##\rho^0 \rightarrow \pi^0\pi^0##, but it is a general doubt.
My book states that one of the reasons why the decay is forbidden is Bose-Einstein statistics, the final state of two equal pions must be in an antisymmetric state...
Hello everybody!
I have a problem with this exercise when I have to find the possible angular momentum.
Since ##\rho^0 \rho^0## are two identical bosons, their wave function must be symmetric under exchange.
$$(exchange)\psi_{\rho\rho} = (exchange) \psi_{space} \psi_{isospin} \psi_{spin} =...
Hello George!
Yes, we use three scintillators at the same time, one over the other. We record a start signal from the passage of a muon in the first and the second scintillator (the events we are interested in are the ones in which the muon stops in the middle scintillator). So the start...
I have attached the file with the set up.
$$ p = (m_k, 0, 0, 0)$$
$$ k_1 = (E_{\nu},0,0, E_{\nu})$$
$$ k_2 = (E_{\mu}, 0,0, -\sqrt{E_{\mu}^2-m_{\mu}^2})$$
Using the conservation of momentum and energy I get:
$$E_{\mu} = \frac{m_k^2+m_{\mu}^2}{2m_k} = 258.15 MeV $$
$$ p_{\mu} =...
My first idea was to find an expression of the muon momentum as a function of the angle and then maximaze the expression. But my attempts were not succesful. I report here my attempt.
Set up (referring to the attached file "bettini.pdf"):
$$ p = (\sqrt{p_k^2+m_k^2},0,0,p_k)$$
$$ k_1 =...