EMR project Overview

Transcription

1 EMR project Overview MICE Collaboration Meeting RAL, May 31, June EMR EMR conceptual design design Mechanical envelope Pending issues issues & outlook outlook University of Geneva: A.Blondel, J-S Graulich, V.Verguilov, F.Masciocchi, L. Nicola, R. Bloch, P. Béné, F. Cadoux 1

2 Thanks to INFN Trieste team, we didn t start from scratch in March 09 (meeting held in Trieste) UniGe took over the EMR mechanics Adapt their first prototype (reduced scale, rectangular bars) Scintillation bars (white painted) WLS optical fibers Moving to Rectangular shaped bars (used for the proto) Triangular shaped bars (1.1m long, from Fermilab) 2

3 Re use their R&D on fiber gluing into the bars (at first) Short length to 1m long bar Use of syringes (top and bottom) Molding compound Tests at UniGe on triangular bars to be performed soon Based on 2 fibers per bars (see previous studies) Start R&D for gluing in parallel (several bars in one go, mass prod )? Same glue as used by INFN Trieste (no safety issue) 3

4 First step: the EMR plane concept (59 bars side by side) EMR will be made of 50 planes (X and Y alternatively) X+Y planes is called Module so 25 modules totally! Designed by Florian Masciocchi (UniGe) Bars fixed to the aluminum beam (see next slides) 59 bars WLS Fibers coming from the bars Aluminum beam removed for clarity 4

5 EMR plane concept (2 beams in aluminum as part of the module mechanics): stress free mounting of the bars (bars to be water jet cut to get a precise length for all in one go ) Single pixel PMT 1mm deep groove (anti rotation + alignment of the bars) scintillators 30mm Al profiles (standard) Multi anodes PMT (64 pixels) Protection box (light tight) 5

6 EMR plane concept : CAD exploded view 1 EMR Conceptual design Double threaded cylinder Grommet for fibers Thru hole for fibers exit Torque value TBD! Nut for bolting 6

7 EMR plane concept : a few figures EMR Conceptual design 30mm Plane Cross section L=990 mm L=1100 mm 16.5mm (hole pattern giving alignment) Fibers going thru the bars and the 2 beams All the grommets in place (In plastic, to prevent any breakage on fibers) X + Y planes together (active surface) will cover nearly 1m 2 7

8 EMR plane concept : Fiber bundles and PMT assembly thru side boxes (1) CAD model side view 2 fibers per bar About 150mm (minimum) 2 side boxes (light tightness) 1 pixel PMT Top part of side boxes removed for clarity 64 pixels PMT 8

9 EMR plane concept : Fiber bundles and PMT assembly thru side boxes (2) Shielding Tube not shown here PMT holder (light tight) Holder in 2 parts (fiber polishing) PMT end cap 64 pixels PMT 9

10 EMR plane concept : Fiber bundles and PMT assembly thru side boxes (3) Pixel Cross talk issue (to be limited by fiber positioning & arrangement) Pixel size: 2x2mm 2 Fiber size: 1mm dia. Fiber filling according to a special arrangement: 2 successive bars are shifted to 1 pixel and so on. bar1 bar3 bar2 10

11 EMR plane concept : Fiber bundles and PMT assembly thru side boxes (4) 1 pixel PMT (from a former experiment at DPNC) Rigidity has been tested on aluminum plates Some loops to get the same length for all the fibers (by CAD: 1200mm +1100mm +1200mm) PMT 11

12 EMR Module concept : 2 planes assembled in X and Y (corner blocks) Also used for handling (40 Kg) X Y First DPNC proto Corner blocks (4 per module) bolted thru the beams Each individual module thru Commissioning prior final integration 12

13 EMR Module concept : 2 modules assembled EMR Conceptual design Electronic boards to be optimized (FEE, HV divider) In case of integration issue It could be reduced 5mm gap between modules 1mm gap between planes 13

14 EMR Module concept : the whole assembly (25 modules ) EMR Envelope Beam Nearly 2500mm 1684mm Stand still to be optimized 1500 mm 14

15 EMR Module concept : the whole assembly (25 modules ) EMR Envelope Every PMT accessible till the last moment Access needed underneath First idea on shielding tube (may too close to each others ) 15

16 EMR Envelope EMR Module concept : The staking of the modules (from 1 side, flexibility for integration) 16

17 EMR Pending issues and outlook Electronics definition: Size of the boards, number, location EMR envelope definition: what is the constraint / neighborhood? FEA simulations still to be performed Magnetic shielding issue: simulations? PMT to be oriented / field? FIRST MODULE PROTOTYPE TO BE ASSEMBLED AT UNIGE BY Oct 09 (still to understand with which electronics for testing purposes, including R&D on multi anode pixels for cross talk issue, light tightness ) 17