All Questions
Tagged with neutrinos homework-and-exercises
20 questions
10
votes
1
answer
3k
views
How much of neutrinos pass through a neutron star?
Neutrino rarely interact with matter however neutron star is extremely dense and I suppose only an insignificant amount of neutrinos can pass through the densest object in the universe second to black ...
- 13.1k
4
votes
3
answers
12k
views
Would a neutrino bomb do anything? Or can weak force kill you?
In a disreputable animated cartoon (I accidentally watch every episode of religiously), a mad scientist plans on killing all humans with a Neutrino bomb.
From context, this is a bomb that produces a ...
- 175
4
votes
1
answer
1k
views
Neutrino decoupling and units
I have a problem that states:
In the early Universe, neutrinos can be created and destroyed by the process:
\begin{equation}
\nu \bar{\nu} \leftrightarrow e^{+}e^{-}
\end{equation}
The thermally ...
- 2,577
4
votes
3
answers
162
views
High intensity laser and neutrino pair production
Given the very small rest mass of the neutrino, visible photons have plenty energy for neutrino pair creation. What would be the probability of $\gamma \to \nu + \bar\nu$?
Would the neutrinos be ...
- 243
4
votes
0
answers
1k
views
Neutrino interaction probability [closed]
Just a quick question, if a single 1GeV neutrino (muon neutrino) were fired at a block of iron with a given density, $\rho$, and the neutrino-nucleon interaction cross section is $\sigma$, what would ...
- 1,644
3
votes
1
answer
539
views
Interaction between neutrino and an anti-neutrino?
What happens when a neutrino and an anti-neutrino interacts together? For example, what does a muon neutrino and anti-muon neutrino produce? it says in my book that it creates "muons and antimuons". ...
- 1,107
2
votes
0
answers
265
views
Using the boltzmann equation to find neutrino decoupling temperature
I'm an undergraduate student currently following a particle astrophysics lecture. I was reading some stuff about the neutrinos decoupling before the $e^+ e^-$ annihilations. It's possible to quickly ...
- 21
1
vote
1
answer
180
views
What lepton neutrino would be in this reaction?
If I have a reaction (shown below), and I'm supposed to work out what the products will be, what would the lepton neutrino $\nu$ be? e.g electron neutrino:
$$ \nu + p \to $$
- 11
1
vote
1
answer
599
views
Minimum energy of a neutrino for charged current reaction with nucleus
I am struggling with a practice problem regarding the following reaction:
\begin{equation}
\nu_{\mu}+n\rightarrow\mu^{-}+p
\end{equation}
The question is "What is the minimum energy of the muon ...
- 71
1
vote
0
answers
36
views
Cloud Chamber Help Needed! [closed]
I was inspired by this video to attempt to create a cloud chamber without dry ice (it's very challenging to get where I live) and I have had limited success so far. This is what the design looks like:
...
- 11
1
vote
0
answers
36
views
How is the fraction of a particular neutrino species calculated?
Suppose we assume that a neutrino is formed in the $\left| \nu_2 \right>$ eigenstate. Then,
\begin{align}
\left| \psi(x, t) \right>
&= \left| \nu_2 \right> e^{-i\phi_2} \\
&= \left(...
- 11
0
votes
1
answer
127
views
What is the bigger number of particles crossing an area: the number of photons or the number of neutrinos? [closed]
Take an squared area with (10²)² m² in front of the sun. What is the bigger number of particles crossing an area: the number of photons or the number of neutrinos?
Just for clarification: you can ...
- 407
0
votes
1
answer
194
views
Decay and Invariant mass [closed]
Consider the following decay :
\begin{equation}
K^+\longrightarrow \pi^0 + e^+ + l^0
\end{equation}
where $l^0$ is a neutral lepton.
What kind of particle is $l^0$?
For $K^+$ , if it's at rest, ...
0
votes
1
answer
42
views
Show that $\nu^c _L = (\nu ^c)_R $
Considering Majorana neutrinos, how can I show that $\nu^c _L = (\nu ^c)_R $?
I don't know how to answer this question.
And what is the difference between $\nu ^c _R $ and $(\nu ^c)_R $? I know it ...
- 759
0
votes
0
answers
43
views
What will happen if neutrinos are not massless particles? [duplicate]
In beta decay, explain qualitatively What will happen if neutrinos are not massless particles?
- 165
0
votes
0
answers
314
views
Summing of neutrino spins in Muon decay
This might be a silly question, but I am just a beginner so please bear with me.
When we average the matrix element over spins, do we also have to sum over neutrino spins since neutrinos are only Left-...
0
votes
0
answers
24
views
Can CC interactions be used to detect oscillations $\bar{\nu_e} \to \bar{\nu_\mu}$?
Can CC interactions be used to detect oscillations $\bar{\nu_e} \to \bar{\nu_\mu}$?
I believe this is not possible because CC interactions occur through the emission of a $W_{\pm}$ boson. This would ...
- 759
0
votes
1
answer
50
views
Limiting the mass of the neutrino for a relativistic case
I came across a question that states
What mass would a neutrino need to still be relativistic today (T = 2.37K) ?
So for a particle to be relativistic we need $pc \gg mc^2$
Well Neutrino was ...
- 3,160
0
votes
1
answer
89
views
Neutrino temperature
I was wondering if anybody knows the relation between the photon temperature $T$ and neutrino temperature $T_{\nu}$? And why this can be written as
$$T_{\nu}=\left(\frac{4}{11}\right)^{1 / 3} T \...
- 1
-1
votes
1
answer
879
views
How to convert this expression from natural units to those used experimentally?
I cannot for the life of me do the correct conversion of the following expression I derived for two flavour neutrino oscillation. I need to convert the expression from natural units ($c = \hbar = 1$ ) ...
