All Questions
43
questions
1
vote
1
answer
118
views
Do all antiquarks carry and anti-color charge, or can they carry RGB color charges as well?
I know there are antiquarks with anticolor charges. Are there also antiquarks that instead carry color charges?
Basically, which of these lists describes the types of quarks that there are:
List one:
...
0
votes
2
answers
76
views
Difference between $ SU(3)$ and $ SU(3)_c $ group
I am reading quark model. I don't understand what's the meaning of a color $SU(3)$ or $SU(3)_c$ group and how it differs from a general $SU(3)$ group. Please elaborate.
3
votes
0
answers
67
views
When do pairs of quarks form jets vs mesons?
For certain processes with low momentum transfer, such as the Kaon decay shown below, quarks will form bound states of mesons.
Whereas for higher momentum-transfer processes, such as the decay of an ...
-1
votes
1
answer
156
views
Why is the electromagnetic force not an emergent property of the strong force? [closed]
Two up quarks in a proton lead to an imbalance, which results in the proton having the ability to attract electrons. Two down quarks in a neutron lead to balance in the electromagnetic force, leading ...
1
vote
1
answer
233
views
Why Lambda Baryon and Sigma Baryon unequal sum isospin with "really" isospin?
For information isospin for $u$-quark = 1/2, isospin for $d$-quark = -1/2 and isospin for $s$-quark = 0.
Lambda Baryon consists $uds$ quarks,therefore sum isospin 1/2-1/2+0=0, It true.
But sum isospin ...
1
vote
0
answers
27
views
Background cuts [closed]
I am considering background events like, $p p \rightarrow t \bar{t}$ and QCD events where t is a top quark. I want also to reduced the QCD events such that QCD events will be less observed than that ...
3
votes
1
answer
530
views
Why do gluon jets have more particles?
From papers on the concept of quark/gluon jet tagging, I've seen that gluon jets have more particles and a broader radiation pattern. Why does carrying more color charge allow them to produce more ...
9
votes
2
answers
286
views
Why are protons/neutrons spin-$\frac{1}{2}$ when they are made up of three valence quarks (also spin-$\frac{1}{2}$)?
If we take the composite angular momentum of the three valence quarks, we should have a proton/neutron spin angular momentum of,
$$S=\{ \frac{1}{2},\frac{3}{2} \}$$
using the general rule for adding ...
1
vote
1
answer
60
views
$\alpha_s$ strength in quarkonium potential energy formula
The top answer to Is there an equation for the strong nuclear force? explains that there is a coulomb's law-like formula:
$V(r)=−\frac{4}{3}\frac{α_s(r)ℏc}{r}+kr$
that describes how quarks and ...
-3
votes
1
answer
209
views
Do Quarks Exist?
Do Quarks Really Exist?
Is there any experiment which can confirm the existence of Quarks and what kind of force is that which binds them to form neutron and proton?
0
votes
1
answer
454
views
Hadronization time
In the process of hadronization what is the characteristic time? I was thinking about at the inverse of $\Lambda_{\rm QCD}$ but can also be a dependence from $\sqrt{s}$. Can anyone help me?
14
votes
5
answers
2k
views
Why aren't all quarks clumped together in one giant hadron?
As far as I am aware, the strong interaction is attractive only, and its carrier, the gluon, is massless meaning it has unlimited range. If this is the case, how come we only observe quarks in pairs ...
2
votes
1
answer
91
views
How is the colour quantum number not conserved in this process?
I stumbled upon this CERN article, where I found this diagram describing the process $gg \rightarrow HH$:
I'm still new to QCD, and I don't see how a coloured gluon can decay into colourless final ...
3
votes
2
answers
689
views
What is "Colombia Plot" in reference to lattice QCD?
In High Energy Physics papers, I often see a diagram as shown below:
I am still studying Quantum Field Theory, and I could not understand the only reference I could find about this plot: https://...
1
vote
2
answers
30
views
Understanding Jet Clustering: Why is only $p_{T}$ used?
Let's only consider iterative jet clustering algorithms. Famous ones are the $k_{T}$ ($p = 1$), anti-$k_{T}$ ($p = -1$) and Cambridge/Aachen ($p = 0$) jet reconstruction algorithms.
All these ...