The Micromegas detector on board two applications … DEMIN & R3B Ph.Legou DSM-IRFU-SEDI Commissariat à l’Energie Atomique (CEA), France Ph.Legou DSM-IRFU-SEDI Commissariat à l’Energie Atomique (CEA), France WORKSHOP IRFU MPGD

DEMIN DEMIN ANCILLARY RACK WORKSHOP IRFU MPGD

DEMIN Concept Thin gas chamber (< 600 mm) Low ionization probability for electrons compare to recoil ions Fast response Spectroscopy based on time of flight technique in counting mode Recoils charged particles liberate ionization electrons in two gas filled gaps defined by three planar electrodes. In the electric fields, electrons are multiplied and drift up to the strips. Electrons produced by g-rays pass through the detector with a lower ionization probability.  Insensitivity to g-rays WORKSHOP IRFU MPGD

On behalf of Rui de Oliveira at CERN the Mesh A « bulk » which can be seen as Other layers of the PCB A Kapton foil streched and glued on a Frame, and the frame is screwed on the PCB Two way of making a mesh for a Micromegas design Improvements are possible (other gap) Ready to use solution Mounting operation is required No improvements + difficult to repair Micromegas : MICROMEsh GASeous

The data acquisition system is a digitizer. 8 channels boards / 20 boards in the VME 6U format -The 4-layers PCB is made by CERN. Strips, spacers and the mesh are sticked on the PCB by a single process. -Preamplifiers (CEA, 1GHz) are plugged on the PCB. - The PCB is 80 channels (low cost). - Detector is shielded by a stainless- steel box. The Detector WORKSHOP IRFU MPGD

Strips, preamplifiers and connectors : good signals integrity Coaxial connectors for analog signals preamplifiersReading strips WORKSHOP IRFU MPGD

DEMIN was installed on OMEGA (LLE) reaction chamber WORKSHOP IRFU MPGD

Dimensions: 23 x 20 x 5 mm Weight : 4 g Power supply : + 5V -5V Consumption  280 mW Input noise  10µV rms In figures … Input : positive ou negative Rise time < 1ns Gain : 30 Cost : 35 $ / Ch The front end electronics WORKSHOP IRFU MPGD

FAMMAS vs commercial Module F1 F6 F4 F2 Amplitude 0.8ns 1.11ns 2.57ns F1 F6 F4 F2 Rise time 10% - 90% Fall time 90% - 10% width Amplitude 1.08ns 2.16ns 3.07ns CEA - FAMMAS Front-end module Minicircuits 1GHz ZFL-1000LN Rise time 10% - 90% width Fall time 90% - 10%

Characterization of the DEMIN in the Laboratory Le 14 février DEMIN – 1100 WORKSHOP IRFU MPGD

DEMIN characteristics WORKSHOP IRFU MPGD

Demonstration of the Gamma insensitivity of the Demin OMEGA DEMIN Scint DD Target, shot DT Target, shot WORKSHOP IRFU MPGD

Secondary neutrons are clearly observed T= 0 1 Secondary neutron (n 2.45,  ) n 2.45 Signal (mV) Time (ns) Signal from channel #4; shot D2-cryo WORKSHOP IRFU MPGD

Counts Neutron energy (MeV) Secondary neutrons spectrum Measurement of secondary neutrons emitted from a pure deuterium cryogenic target implosion at the OMEGA Laser Facility. - A DEMIN with 160 channels is located at 2 meters from the target. - From each individual channel, neutrons signals are taggered in time. The energy spectrum is built from the time of fligth spectrum. WORKSHOP IRFU MPGD

ANCILLARY RACK 70cm=27.5’’ 180cm=71’’ MATACQ digitizers MATACQ digitizers 160 channels (20 cards) 160 channels (20 cards) GPIB/Ethernet interface GPIB/Ethernet interface 3 power supplies for MATACQ 3 power supplies for MATACQ (-7.5V 20A, +7.5V 10A, +5V 10A) (-7.5V 20A, +7.5V 10A, +5V 10A) Gas flow regulator Gas flow regulator Acqiris digitizer (4channels) Acqiris digitizer (4channels) + PC (drives the gas regulator) + PC (drives the gas regulator) NIM crate : NIM crate : DEMIN Polarizations Power supplies for preamps (+5V 5A, -5V 5A) WORKSHOP IRFU MPGD

Conclusions Experiments performed at the OMEGA Facility (Rochester, NY, USA) have shown the γ insensitivity of the concept and successfully achived neutron spectroscopy. The concept is reliable and very low cost. DEMIN bulk detectors have been tested in beam three times during2011, seven years after their fabrication and we can say that the behaviour is still very good! WORKSHOP IRFU MPGD

R 3 B – TPC © Ph. LEGOU & F.G. NIZERY

WORKSHOP IRFU MPGD 1- Motivation 2- Principle of detection 3- Construction of the detector: - the detector - the front-end electronics 4- Results 1- Motivation 2- Principle of detection 3- Construction of the detector: - the detector - the front-end electronics 4- Results Outline

WORKSHOP IRFU MPGD  Where ?  at GSI, just after GLAD magnet.  Who ? (for instance)  several teams of CEA Saclay : SPhN, SIS, SEDI  Cracovie (university and Nuclear Physics institute)  King Saud university (Arabia Saudia)  Bratislava (Nuclear Physics Institute)  Why ?  to measure precisely kinematics characteristics of particles with minimum amount of material in the beam.  What is it? ▪ a multi track Time Projection Chamber detector for protons to beam heavy ions.  When ?  end of 2018 R3B - TPC in few words …. R3B for : Reaction studies with Radioactive Relativistic Beams)

WORKSHOP IRFU MPGD R3B hall in the FAIR facility R3B hall in the FAIR facility GSI FAIR R3BR3B Cave C Still to build

WORKSHOP IRFU MPGD Mesh 10×10 cm  m kapton +5  m Cu Mesh 10×10 cm  m kapton +5  m Cu a 100 µm mesh bulk detector No frame anymore !

WORKSHOP IRFU MPGD R3B – TPC test setup in cave C October 2008 & March 2009 R3B – TPC test setup in cave C October 2008 & March 2009 Six detectors along the beam between scintillators for the DACQ trigger Beam direction

WORKSHOP IRFU MPGD a TracKer channels Width of strips : 835 µm Space between 2 strips : 65 µm Very fast Preamp Mother board Or 7 channels of 5mm with 150 µm between 2 strips.

WORKSHOP IRFU MPGD Characterization of the front-end in the lab Very good uniformity of the noise on the 48 channels front-end cards on each tracker detector

WORKSHOP IRFU MPGD Characterization of the detector Both detectors have the same gain in the area of the operating point.

WORKSHOP IRFU MPGD Test conditions :  visualisation at about 30 meters coaxial cable.  Gaz : COMPASS.  Beam. Mesh Voltage : 350 VMesh Voltage : 370 V Test on a 100 µm gap detector at CERN

WORKSHOP IRFU MPGD Test conditions :  visualisation at about 30 meters coaxial cable.  Gaz : COMPASS.  Beam. Mesh Voltage : 340 V No crosstalk between neighbour channels Test on a 100 µm gap detector at CERN

WORKSHOP IRFU MPGD Tests on a 100 µm gap Bulk detector at GSI … 2008, october 19th. Test conditions :  visualisation at about 30 meters coaxial cable.  Gaz : P10  Beam. Mesh Voltage : 380 V Drift Voltage : 2000V

WORKSHOP IRFU MPGD Signals on resistive Bulk detectors Pics from the scope of two neigbourg strips

WORKSHOP IRFU MPGD Response of three neighbour strips seen by the ADC

WORKSHOP IRFU MPGD Tests on a resistive 100 µm gap Bulk detector at GSI March 2009 in Cave C. « classic 835 µ »« resistive 835 µ » « resistive 5 mm » The charge is more spread on resistive detectors Classical detectors

≈2m Aim of this detector : to test the real drift distance The « One meter » detector test - station The elctrical field cage Electric field cage To provide an uniform fieldIn the whole convertion gap One meter saclay in « lab #534 »

WORKSHOP IRFU MPGD Detection boxes R3B – GSI ≈ 8 m 1,6 m End CapGas enclosure

WORKSHOP IRFU MPGD R3B TPC … the just after GALD magnet and the Helium tank…. ≈ 4 m GLAD magnet Helium tank TPC

WORKSHOP IRFU MPGD Tracks seen by all the chambers C 835 µm R 5 mm R 835 µm C 835 µm

WORKSHOP IRFU MPGD Pads response function of the pads classical 835 µm resistive 835 µm resistive 5 mm

WORKSHOP IRFU MPGD Taking into account : - the transfert properties of the magnet. - the multiple scattering from the target point to the detector. We need a position reconstruction in the TPC of 200 µm RMS