Fermilab

MTest Beam Details

Below are the most commonly used energies. Details that are unknown have been left blank. An explanation of the categories can be found below the table. Please see Particle Composition in MTest for recent updates.

Energy Mode1 Protons Pions2 Highest Intensity3 Muons Kaons electrons Spot Size4 Δp
120 GeV Protons 100% 0 5E5 0 0 0 6mm 2%
60 GeV pions +
50 GeV pions +
40 GeV pions +
32 GeV pions +/-  500,000
30 GeV pions +/-  500,000
25 GeV pions +/-  600,000
20 GeV pions +/-  500,000
16 GeV LEπ +/- 87% 1,000,000 100% 10mm  <4.5%
15 GeV LEπ +/-
12 GeV LEπ –  500000
10 GeV LEπ +/-
8 GeV LEπ +/- 55% 750,000 98% 12mm 2.3%
6 GeV LEπ +
4 GeV LEπ +/- 31% 400,000 74% 13mm 2.7%
3 GeV LEπ +/- 2.7%
2 GeV LEπ +/- <30% 450,000 13mm 2.7%
1 GeV LEπ +/- <30% 69,000 2.7%

 

  1. Mode indicates the configuration of the targets and collimators as explained here.
  2. Pion purity w/lead indicates the 1/4 inch lead scatterer, located in the MT4 region was in the beam. (Usually it is out) The scatterer does reduce intensity.
  3. Highest intensity refers to the highest number of particles per spill yet achived on the MT6SC1 scintillator, at the entrance to the facility, after the cerenkov detectors. It also assumes the lead scatterer is out.
  4. Spot size often depends on vagaries of the upstream tune, so it is not necessarily repeatable.

Don’t see what you need?

There are several targets, absorbers, and collimators in the MTest beamline which can be arranged in different configurations and tuned to produce secondary particles at single energies in the following configurations:

  • 120 GeV: Protons
  • 60 – 8 GeV: Pions, (some protons possible)
  • 32 – 1 GeV: Pions, electrons, kaons, or broadband muons
  • 1 GeV – 200 MeV: Pions, protons, kaons (Only available in ‘Tertiary’ Beamline)

If you are interested in a combination not listed above, contact the FTBF coordinator.

Energy resolution

Several measurements on beam momentum spread for electrons were performed and we consistently obtained 3% or better resolution from the lead glass calorimeter.  Some of that spread can be attributed to the finite resolution of the calorimeter itself, so we estimate a 2 to 2.5% momentum spread for a wide variety of tunes.  Since the beam is steered horizontally before the MT6 enclosure, there will be a dependence on position of the momentum, and thus it is possible to obtain better momentum resolution by correcting for position.

Tertiary beam – Now moved to MCenter

minervaBeam