Science and Technology at the LHC
riccardo.de.maria@cern.ch
Elementary particles are massless, the
Higgs field couples at very small
scales with all particles but photons
and the net effect results in an
effective mass.
Particle rest mass and energy are
given in units of eV: the energy of an
electron charge accelerated by
potential of 1V.
Higgs(-like) Boson Discovery 2012
The Large Hadron Collider
2808 bunches · 1.15 1011 protons at 7 TeV each. =
2808 · 1.15 · 1011 ·7 · 1012 · 1.602 · 10-19 Joules = 362 MJ per beam
LHC Complex
Lorentz Force for Relativistic Particles
β=v /c γ=1/ √(1−β2)
p=γ m v
F = ṗ
⃗ =q( ⃗E+⃗v × ⃗B)
F
Lorentz Force
Centrifugal Force
Beam Rigidity
E
F =q v B
F =γ m v 2 ρ
p
=B ρ
q
pc=7000GeV
∫ E ds=16 MV
B≈8.3T
ρ≈2.8 km
LHC Dipoles
Dipole Current = 12.5 kA
Dipole Inductance = 0.1 H
Dipole Stored Energy = 7 MJ
1232 Dipoles → 9 GJ Stored Energy
Coils and Cables
LHC Magnet cables
Rutherford Cable
15 mm
1 mm
Filaments
6 um
∇ ×E =−
∂B
∂t
B
z
t=1000 s
L
Current at the cable edge
Measure of a magnetic field error
L
L
I
B3
B1
z
Tempo [s]
tempo
Z [mm]
Experimental evidence: an oscillating magnetic field error with a periodicity
equal to the loop length is measured in every superconducting magnet.
Dipole Powering
dI
V =R I +L
dT
I ≈12.5kA
R≈0.8 m Ω
L≈8H
2008 Incident
Lost of superconductivity in one interconnection
2009-2012 Operations
Particle Transport
For stability:
Linear restoring force
∇⋅B=0
∇ ×B=0
∂2 B x ∂2 B y ∂2 B z
+
+
=0
2
2
2
∂x
∂y
∂z
Long magnets
2
B y +i B x =( B 1 +i A1 )+( B 2 +i A2 )( x +i y)+( B3 +i A3 )( x+i y) +...
B1 <0
B2 >0
^y
x^
^z
⃗ =q ⃗v × ⃗B
F
B3 <0
Alternating gradient
CERN Complex
HL-LHC Upgrade Project
Hardware for the HL-LHC
Crab cavities
Nb3Sn quadrupoles
Superconducting links
Studies for the next collider
Large Hadron Electron Collider
International linear collider
High Energy LHC
LEP3, Very High Energy LHC
84km
31km
Student Programs
●
Summer Student program
–
●
Technical Student program
–
●
July August
6 to 12 months
Doctoral Student program
–
2 to 3 years
Informations at www.cern.ch
Joint University Accelerator
School