externaltargetfacility at csr frib-china east lansing 2015.5.28-30 sun, zhiyu institute of modern...

External Target Facility at CSR

FRIB-China East Lansing 2015.5.28-30

Sun, Zhiyu

Institute of Modern Physics, CAS

CSRe

SFC (K=69)10 AMeV (H.I.), 17~35 MeV (p)

SSC(K=450) 100 AMeV (H.I.), 110 MeV (p)

CSRm 1000 AMeV (H.I.), 2.8 GeV (p)

Providing stable beams and RIBs with energies from MeV/u to GeV/u

National Laboratory of Heavy Ion Accelerator in Lanzhou

RIBLL1RIBs at tens of AMeV

RIBLL2RIBs at hundreds of AMeV

HIRFL(Heavy Ion Research Facility in Lanzhou)


HIRFL Research Programs

• Nuclear Physics– Nuclear spectroscopy

– Super-Heavy Element (SHE)

– Radioactive Ion Beam (RIB) physics

– Reaction dynamics and nuclear matter

• Atomic Physics• Material Science

• Radiation Biology and Medicine

• Accelerate and related technology

• Electronics and detector development


① Low energy site in general ② Atomic physics exp. site ③ SHANS - Spectrometer for Heavy Atom and Nuclear Structure

④ Heavy ion irradiation exp. site

⑤ RIBLL1 – 1st Radioactive Ion Beam Line in Lanzhou

⑥⑧ ETF – External Target Facility at CSR ⑦ CSRe – Experimental Ring ⑨ Tumor therapy site

HIRFL: Experiment Setups


SFC

TR5

TR3TR4

TR2

TR1

TL2

TL1

SSC PDC

T1

RIBLL1

RIBLL2

PT

CSR

m

Experiments at the CSR-ETF

Study the structure of unstable nuclei through few-body reactions such as Coulex, Knock-out and break-up.

Study the density and isospin dependence of the Equation of State (EOS) in the supra-saturation density

RIB Physics

Properties of Nuclear Matter



Dipole

Array

Tracking T0

Neutron Wall

TOF Wall

• A multi-purpose setup• measure charged particles, gs and

neutrons at the same time• completely kinematic measurement

σ(E)/E=3%

σ(E)/E=2%

σ(E)/E=1%

2.9°

2.0°1.8°1.6°

1.3°1.2°500MeV/u


Material: CsI(Tl)Coverage ： 6°~129.2°Module number: 4608Volume (Crystal) ： 226,762 cm3

Weight (Crystal) ： 1,021 kg

Measure g rays up to 15 MeVLarge coverageGood efficiencyGood energy resolutionGood Doppler correction

The CsI g Detector Array

For the 1st stage, the end-cup has been constructed.coverage ： 15.6°~36.4°Module number ： 1024Volume (Crystal) ： 44,177 cm3Weight (Crystal) ： 200 kg

700MeV/u500MeV/u300MeV/u100MeV/u50MeV/u

700MeV/u500MeV/u300MeV/u100MeV/u50MeV/u

6° 36.4°

129.2°15.6°


G=3.29%


Readout with APD(Hamamatsu S8664-1010)

137Cs （ 662keV ）Homogeneit

y

Electronics


ASIC chip MATE3

simulation

measurement

backscattering peak


Coverage ： 6.0 %×4π

E（ MeV）

Efficiency Total absorbtion

1.17 99.5% 64.8%

1.33 98.5% 61.3%

Efficiency for the g rays within the coverage(simulation) ：

Still working on the spectrum reconstruction process now, will do calibration and compare with the simulation after this.

FWHM ≈ 8%60Co


Pole gap: 27 cmEffective length: 1 mMax. Field: 1.5 T

The Dipole Magnet

The TOF Wall Detector

Get the momentum of charged particles by the time of flight measurements

Active area 1.2×1.2m2

Time resolution(σ)

150 ps30 modules in one layer


Readout from both sides by PMT

Module Performance with cosmic rays

The charge obtained from one PMT will vary for 300% while the hit position moves

The average has less dependence on hit position

The effective velocity of light transfer is about 15 cm/ns, leading to a position resolution of about 2 cm (σ)



Time resolution: σ~70 ps (corrected, center position)

Time resolution(σ) is better than 150 ps （ LED after correction ）

test with 100 MeV/u 12C beam

test with cosmic rays

Timing measured by HPTDC in the high-resolution mode (25ps), Charge measured by TOT method with a resolution of 5%

Electronics


The MWDC Detectors


Active size 96×50 cm2 80×60 cm2 48×32 cm2

Quantity 1 5 1

Wires readout 576 480 288

Position resolution (σ) ~260 μm ~230 μm ~200 μm

Efficiency (MIPs) >95% >95% >95%

• SFE16 as pre-amplifier and LED• Timing measured by HPTDC in the normal-resolution mode (100ps) • Charge measured by TOT method• 128 channels/board


85 ％ Ar ＋ 15 ％ CO2

neutron energy range： tens MeV～GeV

time of flight method

high efficiency

good momentum resolution

large coverage

good positon resolution

150 MeV

Neutron Wall detector


14Layers, 18Modules/Layer

The first 2 layers consists of plastic scintillator only

Other 12 layers are scintillator+iron configuration

Consists of 76cm scintillator and 24cm iron totally

Read-out from both ends of every module by PMT

Coupled with a veto detector consists of 1cm plastic scintillator


Active volume: 1.5×1.5×1m3

Distance to target: 14 m

Energy resolution: 5% (1GeV)

Module performance (cosmic rays)


Scintillator module Scintillator+iron module

Module performance (beam)

Beam ： 100 MeV/u 12C6+

Target ： Fe （ 8 mm ）Flight length ： 1 m


VETO ： 150cm×8cm×1cm

Module tested

100 MeV/u 12C6+ Pb


Time resolution for the scintillator module: 50ps for charged particles and 230ps for neutrons

Charged Particles Neutrons

Time resolution for the scintillator+iron module: 120ps for charged particles and 350ps for

neutrons

N

CSRm

CSRe

SFC

SSC

SFC: 10 AMeV (H.I.), 17~35 MeV (p)

SSC: 100 AMeV (H.I.), 110 MeV (p)

CSRm: 1000 AMeV (H.I.), 2.8 GeV (p)

CSR External Target

Experiment


Spokespersons:Prof. Xu Nu Xiao Guo-Qing

Study the properties of nuclear matter at CSR

CEE (CSR External Target Experiment)


Momentum resolution <5%

Time resolution <70 ps

Event rate 103~104/s

Date taken ~500MB/s

CEE:1) Extreme high baryon density

and low temperature region2)Strong hadronic interactions

Net baryon density

Target

MWDC

TOFW

Big Dipole

Beam

π—

π+p

Can we work with the existing setup?

Start


p/Z (MeV/c)m

/Z (

MeV

/c2 )

Target

MWPC

TOFW

Big Dipole

Start

Beam

π—π+p

B= 0.27 Tesla

π— π+p

B= - 0.27 Tesla


proton

π+

π-

Elab=200AMeV

Elab=600AMeV

Summary

• The experiments at CSR-ETF will focus on the RIB physics and the properties of dense nuclear matter

• A multi-purpose setup is under-construction at the CSR-ETF for RIB physics, and the detectors are nearly ready for commissioning.

• Need more hard works to make the new CEE spectrometer approved, and we can use the setup for RIB physics to start the work on EOS at the same time.


Thank!

externaltargetfacility at csr frib-china east lansing 2015.5.28-30 sun, zhiyu institute of modern...

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