High rate electron beam tests with MuPix sensors at MAMI

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High rate electron beam tests with MuPix sensors at MAMI

Carsten Grzesik

Institute for Nuclear Physics Mainz

January 16, 2018

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Outline

I Mainz Microtron (MAMI) accelerator

I MAMI testbeam locations

I MuPix sensor

I MuPix testbeams at MAMI

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The MAMI accelerator

I 4 stage electron accelerator

I 1.6 GeV at 100µA

I 82 % polarization (max. 20µA)

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Accelerator stages 1-3 - MAMI-B

I Linear injector

I 3 stage racetrack microtrons

I Energies[MeV]:

14, 180, 855

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Accelerator stages 1-3 - MAMI-B

I Linear injector

I 3 stage racetrack microtrons

I Energies[MeV]:

14, 180, 855

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Accelerator stage 4 - MAMI-C

I Harmonic double-sided microtron

I Output energy:

1.6 GeV

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MAMI operation

I Up to 70 % duty cycle

I December 2017 missing (≈150 h unpolarized)

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Testbeam locations

I X1: behind RTM 3

I A2 hall: tagger magnet

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HV-MAPS - MuPix sensor prototypes

P-substrate N-well

Particle E field

I 180 nm HV-CMOS technology

I Reverse biased up to 90 V

I Readout logic on chip

I Thinnable down to 50µm

I MuPix7

I Pixel size: 80×103µm²

I Sensor size: 3×3 mm²

I Used in Mu3e, P2

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Testbeam locations

I X1: behind RTM 3

I A2 hall: tagger magnet

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X1 - high rate electron testbeam

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X1 - high rate electron testbeam

Rate [1/s]

0 500 1000 1500 2000 2500

103

×

Efficiency

0.99 0.991 0.992 0.993 0.994 0.995 0.996 0.997 0.998 0.999 1

/ ndf

χ2 14.63 / 63

p0 0.9975 ± 0.0001364 p1 −1.204e−09 ± 8.574e−11

/ ndf

χ2 14.63 / 63

p0 0.9975 ± 0.0001364 p1 −1.204e−09 ± 8.574e−11 Efficiency vs rate

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A2-Glasgow-Mainz tagger - photon testbeam

E0= 450MeV

Vacuum Window (Mylar) Permanent

Magnet MuPix Sensor Dipole

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A2-Glasgow-Mainz tagger - photon testbeam

50 100 150 200 250 300 350 400

Photon Energy / MeV 0.5

1.0 1.5

ηdet2.01e-3

MC prediction

Corrected Data with stat. error Systematic error

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A2-Glasgow-Mainz tagger - electron testbeam

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A2 electron beamline extension - new 2017

I A2 hall: beamline extended through Crystal Ball

I No radiator, tagger magnet off

I E_beam= 700 MeV

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TPC testbeam - setup in A2 hall

I MuPix telescope

I High preasure helium TPC

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TPC testbeam - observations

0 5 10 15 20 25 30

0 5 10 15 20 25 30 35

pixel_map_0_

Entries 6259201 Mean x 17.91 Mean y 20.5 Std Dev x 3.881 Std Dev y 8.043

1 10 102 103 104 pixel_map_0_

pixel map for sensor 0_

Beamspot

0 5 10 15 20 25 30

0 5 10 15 20 25 30 35

pixel_map_0_

1 10 102 103 104 105 pixel_map_0_

pixel map for sensor 0_

Background after 2 MHz hit rate

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TPC testbeam - results

I MuPix telescope operation

I Beam monitoring

I Provide reference tracks

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Summary

I MAMI provides polarized electron beam up to 1.6 GeV

I Electron & photon testbeams possible

I MuPix high rate capabilities tested

I MuPix telescope provides reference tracks up to 2 MHz

I MuPix8 to be tested in March

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Backup - A1

I Electron scattering

I 3 rotatable spectrome- ters

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Backup - A2

I Photoproduction by Bremsstrahlung

I Beam electrons deflected and tagged by spectrometer

I Meson radiation of target nucleons

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Backup - A4

I Elastic electron scattering

I Longitunally polarized electrons

I Unpolarized H₂ target

I Measure parity violating asymmetry

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Backup - MESA

I Mainz Energy Recovering Superconducting Accelerator (MESA)

I 2 modes, up to 155 MeV, 85 % polarization

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Backup - P2 experiment

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Backup - P2 spectrometer and tracking system

I 0.6 T solenoid magnet

I Inhomogenous field in tracking system

I Measure the average Q²

I Validate acceptance, alignment

I Monitor beam and target conditions

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Backup - P2 tracking detector

I Pixel sensors, electronics, gaseous helium cooling, mechanical support

I Low material budget

I 2×4 modules, double layers, 300 sensors per layer