Register to reply

The origin of baryon number

by guest1234
Tags: baryon, number, origin
Share this thread:
guest1234
#1
Jan10-14, 06:39 AM
P: 30
I'm doing a little research on quarks on stumbled upon the baryon number. Wikipedia says that the notion predates the quark model. I have no clue why particle physicists were motivated to introduce it before flavour quantum numbers came to the scene.

So... What's the (historical) origin of baryon number?
Phys.Org News Partner Physics news on Phys.org
'Squid skin' metamaterials project yields vivid color display
Team finds elusive quantum transformations near absolute zero
Scientists control surface tension to manipulate liquid metals (w/ Video)
Vanadium 50
#2
Jan10-14, 07:04 AM
Emeritus
Sci Advisor
PF Gold
Vanadium 50's Avatar
P: 16,461
Baryon number as a conserved quantity was to explain why you didn't see decays like p -> e+ pi0.
Meir Achuz
#3
Jan10-14, 07:05 AM
Sci Advisor
HW Helper
PF Gold
P: 2,024
In all known experiments so far, the number of baryons is conserved, and the notion goes back to the early beta decay experiments. This has nothing to do with quarks, but most quark models incorporate baryon number conservation. Some extended symmetry theories predict proton decay into leptons and mesons which would violate baryon number conservation.

Simon Bridge
#4
Jan10-14, 07:09 AM
Homework
Sci Advisor
HW Helper
Thanks
Simon Bridge's Avatar
P: 13,051
The origin of baryon number

Well baryons were observed before the quark model and their behaviors documented.

One of the things researchers try is to sort things into groups and see what makes sense.

Doesn't it seem reasonable to count matter as +1 and antimatter as -1? Once you've done that for nucleons, and looked at what happens to the numbers in various nuclear reactions, what would be a sensible number to give mesons?
PAllen
#5
Jan10-14, 09:05 AM
Sci Advisor
PF Gold
P: 5,080
Where the quark model helps explain baryon number is motivating why baryon number of mesons is zero (quark/antiquark pair). Baryon number could be replaced with quark number, but everyone was used to baryon number.
guest1234
#6
Jan10-14, 10:27 AM
P: 30
Thanks everyone for your input! Got the type of answers I wanted.


Register to reply

Related Discussions
Conservation of Baryon Number Quantum Physics 5
Origin of terminology (baryon number, hypercharge, strangeness) High Energy, Nuclear, Particle Physics 2
Are there any GUT's that do not violate baryon number? Beyond the Standard Model 10
Baryon Number Non-Conservation High Energy, Nuclear, Particle Physics 8
Violation of Baryon Number Beyond the Standard Model 5