What Causes a Narrow Resonance in Particle Spectra?

  • Thread starter HAMJOOP
  • Start date
  • Tags
    Particle
In summary, to find a new particle, the energy and momentum of the (decayed) particles are measured and evaluated using the expression m^2 = E^2 - p^2. A histogram is then plotted to show the data. It is important to consider not just the peak in the histogram, but also the rapid increase in the phase of the partial-wave scattering amplitude, as well as possible threshold cusps, when identifying a resonance particle. Particle detection experiments typically try to avoid these thresholds.
  • #1
HAMJOOP
32
0
To find a new particle, the energy and momentum of the (decayed) particles are measured
Evaluate the expression m^2 = E^2 - p^2 and plot a histogram.

I just don't understand why there is a resonance particle if there is a peak in the histogram.
Is it because the probability is very high and we regard it as a particle ??
 
Physics news on Phys.org
  • #2
Where else would the peak come from?
 
  • #3
Simon Bridge said:
Where else would the peak come from?
A threshold cusp, for one thing. http://arxiv.org/abs/hep-ph/0406293

Indication of a resonance comes not just from a peak in the partial-wave scattering amplitude, but also a rapid increase in its phase. This recently played a role in the identification of Z(4430) as a candidate for a four-quark state. http://arxiv.org/abs/1404.1903
 
Last edited:
  • #4
... OK, but I wanted HAMJOOP to think about it first.
(In the context in which the question was asked...)
 
  • #5
Simon Bridge said:
... OK, but I wanted HAMJOOP to think about it first.
(In the context in which the question was asked...)
Sorry, I just thought it was an interesting question. Did I get it right? :smile:
 
  • #6
Well it is the interesting form of the original question yes.
A narrow resonance in a spectra could be a wigner cusp - usually a scattering experiment... occurs near the threshold where one channel comes to dominate another one.

Particle detection experiments try to avoid these thresholds.
It's the other half fo the answer OP is looking for. The graph, by itself, is not the whole story.
 

1. How do scientists discover new particles?

Scientists use a variety of methods to discover new particles, such as analyzing data from particle accelerators and conducting experiments to observe the behavior of particles.

2. Why is the discovery of new particles important?

The discovery of new particles can help us better understand the fundamental building blocks of the universe and the laws of physics that govern them. It also has practical applications in fields such as medicine and technology.

3. What tools and technologies are used to find new particles?

Particle accelerators, detectors, and advanced computer simulations are some of the tools and technologies used by scientists to find new particles. These tools allow them to create and study the behavior of particles in controlled environments.

4. How do scientists determine if a new particle has been discovered?

Scientists use statistical analysis and multiple experiments to confirm the existence of a new particle. They compare the data from these experiments to established theories and models to determine if the new particle fits into our current understanding of the universe.

5. What are some recent advancements in the search for new particles?

Recent advancements include the discovery of the Higgs boson in 2012, the observation of gravitational waves from merging black holes in 2015, and the detection of the first-ever direct image of a black hole in 2019. Scientists continue to build and upgrade particle accelerators and detectors in hopes of finding new particles and expanding our understanding of the universe.

Similar threads

  • High Energy, Nuclear, Particle Physics
Replies
6
Views
1K
  • High Energy, Nuclear, Particle Physics
Replies
1
Views
1K
  • Beyond the Standard Models
Replies
4
Views
902
  • High Energy, Nuclear, Particle Physics
Replies
11
Views
1K
  • High Energy, Nuclear, Particle Physics
Replies
16
Views
2K
  • High Energy, Nuclear, Particle Physics
Replies
11
Views
1K
  • High Energy, Nuclear, Particle Physics
Replies
7
Views
1K
  • High Energy, Nuclear, Particle Physics
Replies
4
Views
2K
  • High Energy, Nuclear, Particle Physics
Replies
8
Views
967
  • High Energy, Nuclear, Particle Physics
Replies
4
Views
2K
Back
Top