# Lepton number in electron capture

#1
https://www.dropbox.com/s/dofptcijg5...epton.JPG?dl=0

How is the lepton number conserved in this electron capture.
19 + 1 doesn't not equal 18 + 1

Many thanks
0
4 years ago
#2
(Original post by clausencallum)
https://www.dropbox.com/s/dofptcijg5...epton.JPG?dl=0

How is the lepton number conserved in this electron capture.
19 + 1 doesn't not equal 18 + 1

Many thanks
K and ar are elements not leptons
0
#3
(Original post by kishxx01)
K and ar are elements not leptons
but they have electrons so surely they have lepton number?
0
4 years ago
#4
Well firstly you shouldn't be taking into account the atomic number; lepton number is conserved.

Potassium has 0 lepton number. The electron has a lepton number of +1.

Argon has 0 lepton number number. The electron neutrino has a lepton number +1

0 + 1 --> 0 + 1
1=1

Lepton number conserved.

Your thinking is incorrect because in electron capture, a proton decays into a neutrino by capturing an inner shell electron (it's in the name!). Therefore, both the proton number and the number of electrons in the atom decrease by 1.

EDIT: so it's actually 18 + 1 --> 18 + 1
19=19 hence lepton number is conserved.
0
4 years ago
#5
(Original post by clausencallum)
but they have electrons so surely they have lepton number?

(Original post by BTAnonymous)
Well firstly you shouldn't be taking into account the atomic number; lepton number is conserved.

Potassium has 0 lepton number. The electron has a lepton number of +1.

Argon has 0 lepton number number. The electron neutrino has a lepton number +1

0 + 1 --> 0 + 1
1=1

Lepton number conserved.

Your thinking is incorrect because in electron capture, a proton decays into a neutrino by capturing an inner shell electron (it's in the name!). Therefore, both the proton number and the number of electrons in the atom decrease by 1.
0
#6
(Original post by BTAnonymous)
Well firstly you shouldn't be taking into account the atomic number; lepton number is conserved.

Potassium has 0 lepton number. The electron has a lepton number of +1.

Argon has 0 lepton number number. The electron neutrino has a lepton number +1

0 + 1 --> 0 + 1
1=1

Lepton number conserved.

Your thinking is incorrect because in electron capture, a proton decays into a neutrino by capturing an inner shell electron (it's in the name!). Therefore, both the proton number and the number of electrons in the atom decrease by 1.

EDIT: so it's actually 18 + 1 --> 18 + 1
19=19 hence lepton number is conserved.
But why do elements not have lepton numbers?
0
4 years ago
#7
(Original post by clausencallum)
But why do elements not have lepton numbers?
What is a lepton? It's a fundamental particle cannot decay by the strong nuclear force. Are elements fundamental particles? No. They are made of electrons, protons and neutrons.

You're thinking about the number of electrons in the atom aren't you?
0
#8
(Original post by BTAnonymous)
What is a lepton? It's a fundamental particle cannot decay by the strong nuclear force. Are elements fundamental particles? No. They are made of electrons, protons and neutrons.

You're thinking about the number of electrons in the atom aren't you?
yep
0
4 years ago
#9
19-1=18+0
0
4 years ago
#10
(Original post by clausencallum)
yep
Yeah, well if you want to think about it like that then you need to consider the fact that the electron is coming from one of the 19 electrons in the K atom. This electron which is being captured is part of the 19 electrons in the K atom, it's not a random free electron which is colliding.

So it isn't 19 + 1 but 18 + 1.
0
#11
(Original post by BTAnonymous)
What is a lepton? It's a fundamental particle cannot decay by the strong nuclear force. Are elements fundamental particles? No. They are made of electrons, protons and neutrons.

You're thinking about the number of electrons in the atom aren't you?
guessing elements dont have a baryon number either then?
0
4 years ago
#12
(Original post by Rhiaaaaa)
18+1=19+0
18+1-->18+1
0
4 years ago
#13
(Original post by BTAnonymous)
18+1-->18+1
Liar
0
4 years ago
#14
(Original post by Rhiaaaaa)
Liar
How so?
0
#15
(Original post by BTAnonymous)
18+1-->18+1
ok, I think just knowing that elements dont have baryon and lepton numbers for aqa a level physics will be ok. Many thanks though
0
4 years ago
#16
(Original post by clausencallum)
ok, I think just knowing that elements dont have baryon and lepton numbers for aqa a level physics will be ok. Many thanks though
Yh, just think of it like that.
0
4 years ago
#17
(Original post by BTAnonymous)
How so?
I WAS TALKING ABOUT CHARGE. Idk what lepton number is TELL ME
0
4 years ago
#18
(Original post by Rhiaaaaa)
I WAS TALKING ABOUT CHARGE. Idk what lepton number is TELL ME
0
4 years ago
#19
for physics do we need to know the baryon and lepton number for each particle?
0
4 years ago
#20
(Original post by BTAnonymous)
Tell me idoot
0
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