A solenoid pion collector for ESSnuSB Maja Olvegrd October 7, - - PowerPoint PPT Presentation

A solenoid pion collector for ESSnuSB

Maja Olvegård October 7, 2014

Magnetic Pion Collectors

• Positron sources

– matching to accelerator optics

• Neutrino factories / Muon colliders

– nature of focusing? matching?

• Superbeam facilities

– point-to-parallel focusing

Three solenoid types

Standard (S) Quarter Wave Transformer (QWT) Adiabatic device (AD) beam

The pions

• Large momentum spread
• Large angular divergence

– Max intensity at

• What energy (range) are we targeting?

– Single energy (standard solenoid) – Maximum energy? (adiabatic solenoid) – Central energy? (quarter wave transformer)

Pion distribution provided by N. Vassilopoulos.

Specifications from Physics needed!

Important problems

coil

• Hard-edge done. Turn to “physical”

magnet with fringe fields.

• Source inside or (partially) outside the

solenoid?

• How to do the charge separation?

― Add a chicane? ― Tilt the solenoid?

• Available space?
• How much contamination can we accept?
• Later: try more complex systems (e.g.

adiabatic solenoid system)

• Several codes for particle tracking:
• Particle interaction with matter: FLUKA/GEANT4

Tracking codes

source import magnet availability comment Parmela/Parmila 3D yes map UU license exists. Tredi 3D GPT 3D ? map License required. Astra Open source IMPACT PARTRAN Matlab “manual” work

• Potential showstoppers:

a) The solenoid provides significantly (at an unacceptable level) lower collection efficiency b) The charge separation is too complex. c) The heat load on the superconducting coil is excessive.

• Strategy to deal with the scenarios above:

–

If a) and/or b) is true, terminate the study.

–

If a) and b) are false, increase efforts to face c).

• Timeline:

–

Investigate a) and b) before March 2015.

–

Boundary conditions:

• Design study application is approved.
• My contract expires June 30, 2015.

Strategy

• Jean-Pierre
• Maja

– part time until July 1, 2015

• Volker
• Roger
• ...

Available resources

Hard-edge solenoid

• Source outside of solenoid

– a max to be captured

• Source inside the solenoid

– discrete energy selection: Particles with momenta

will exit the magnet with zero transverse momentum ( = point-to-parallel focusing)

• Pion rest mass and half life
• Pion momentum and total energy
• Relativistic gamma factor
• Pion speed
• Distance traveled in lab frame
• Muon life time ~100 time longer. Rest mass about the same

which means that muons travel ~100 times longer before decaying.

Available space

( for ) ( for )