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APP Introduction to Astro-Particle Physics
Maarten de Jong
1
Particle physics
Astrophysics
Cosmology
What is APP?
This course will have a particle physics approach. 2
Chapter 1 Chapter 2, 3, 6 Chapter 11 Chapter 12, 13, 14 Chapter 15
3
useful coordinates
E-mail URL http://www.nikhef.nl/~mjg/Leiden/APP
http://www.nikhef.nl
4
The bottom line
homework ~40% – study of articles, scientific proposals, …
• group of 3 – 5 students • written reports and/or oral presentations
exam (written) ~60% – 4 – 5 exercises
• December 21, 2012, 10:00-13:00 room HL106
Number of EC points 6 5
What is (cosmic) matter made of?
6
!
7
θ
extended charge distribution
point like particles
num
ber o
f eve
nts
beam of particles θ
n p
0 0
0K K K Kρ ρ ρ ωφ
∗− ∗ ∗ ∗+
+ −
0π π π− +
0
0
− +
−Σ Σ ΣΛ Ξ Ξ
0 0K K K K η− +Mas
s sp
ectru
m o
f had
rons
scattering off target protons
8
1960’s → today
quark-parton model ↓
standard model of particles and fields
9
particles
q e µ τ –1 νe νµ ντ 0 u c t +⅔ d s b –⅓
flavour
leptons
quarks
particle
10
fermions
spin ½ particle
11
interactions
interaction mediator spin/parity
strong gluon (g) 1–
E-M photon (γ) 1–
weak W±, Z0 1–, 1+
gravity graviton? 2+
12
bosons
spin 1, 2, … particle
13
photon
1) mediator of E-M interaction 2) mass-less ‘particle’
14
photon astronomy
1’ 1’ 1’ 1’
radio 10-8 eV optical 10 eV X-rays 104 eV gamma rays 1012 eV
broadband feature
Crab nebula
15
hcEγ
λ =
Planck constant speed of light
Energy of ‘particle’
Wavelength:
16
Mass of elementary particles?
17
quarks leptons bosons
Z
W
e
µ τ
ντ
νµ
νe
solar ν oscillations
atmospheric ν oscillations
u d
c b
s
t M
ass
[eV/c
2 ]
mγ < 10-15 eV
18
origin of mass?
Higgs search
19
strong E-M weak gravity
1 10-2 10-7 10-39
nucleus atom ? planets stars
interactions (II)
20
conservation rules
energy-momentum charge lepton number (e,µ,τ) baryon (qqq) number …
21
Radio-active decay
1Z ZN NA A e±→ +
12 2
Z ZN N
E M c M ce A A± = −
2-body decay?
22
Radio-active decay (II)
Ee±
Num
ber o
f eve
nts
Energy not conserved?
observed energy spectrum of e±
12 2
Z ZN N
M c M cA A−
23
en p e ν→ + +
n p
d d u u
d u
e
eνW–
Feynman diagram
not detected Pauli (1930):
Fermi: Weak interaction
24
Fundamental forces
Energy
25
Atomic Mass Unit
12
2931.494028(23)
12
2
1
Camu
E mc
M MeVc
Eamu
≡ =
=
∈≡ ≤Energy ratio: 26
Chemical energy
2 2 2n mC H O CO H O x eV+ → + +
1.5 Volt
10 910 ( 10 / )10
x eVx J kg
amu−∈ =
E-M interaction: α = 1/137
27
Nuclear energy
235 92 141 3U n Kr Ba n x MeV+ → + + +
510100x MeV
xamu
−∈ =
Strong interaction: αs ≈ 1
28
dr
r
A = 4πr2
2
2
03 2
0
2 4
03 2
2
( ) 4
4 43
(4 )3
4 3( )3 5
35
RN
R
N
R
N
N
N
G M r rV dr
r
r rG dr
r
G dr r
G RR
G MR
π ρ
π ρ π ρ
πρ
π ρ
=
=
=
=
=
∫
∫
∫
Gravitational energy
4π ρ r2dr 2
0
( ) ' 4 'r
M r dr rρ π= ∫
1 2NG M MV
r=
29
Stellar implosion
2
2 1
51
2
46
1 135
7 10
15
2 10
NE G MR R
M M
R R km
R km
E J
= −
=
= ×
=
↓
×
e-
p Å = 10-10 m
fm = 10-15 m
n
30
Stellar implosion (II)
46
33
2
2 10
1.99 10
10%
E J
M g
E M c
×
= ×
↓
×
¶ Weak field approximation!
¶
Gravitational force is accumulative: ? E MM
∝
31
Energy barrier
p e n eν+ → +
2
939.566 938.272 0.5110.784
10%
n H n p e
p
m m m m m
MeVMeV
m c
− − −
− −
32
Solar luminosity
26
93.92 10
4.5 10
L W
T y
=
=
Luminosity
Age
chemical
26 9 7
9
34 30
3.92 10 4.5 10 3 10
10 /
5 10 2 10
L TM
EM
W s
J kg
kg M kg
×∆ =
∆
× ×=
=
33
hydrogen burning
44 2 2 ep e He ν+ → +
44 26.731p HeM M MeV− =
146 10E JM kg∆
=
detected!
34
Solar luminosity (II)
26
93.92 10
4.5 10
L W
T y
=
=
Luminosity
Age
26 9 7
14
28
3.92 10 4.5 10 3 10
6 10 /309 10 2 10
L TM
EM
W s
J kg
kg M kg
×∆ =
∆
× ×=
= =
nuclear 35
Milky Way 36
104 10
1 10
L W
T y∗
∗
=
=
Luminosity
Age
36 10 739
14
4 10 1 10 3 102 10
6 10He
L TM kg
EM
∗ ∗× × ×= = =
∆
He has cosmological origin
1% 24%HeM M M∗ ∗ observed
36