Status of EIC Calorimeter R&D at BNL

EIC Detector R&D Committee Meeting

January 13, 2014

S.Boose, J.Haggerty, E.Kistenev, E,Mannel, S.Stoll, C.WoodyPHENIX Group

E.Aschenauer, A.KiselevSPIN and EIC Group

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 2

Progress Since Last Meeting (June 2013)• Studied response of calorimeter design with Monte Carlo

• Completed construction of new EMCAL prototype

• Completed design of readout electronics, fabricated all preamps, and started testing readout system

• Designed calibration system and installed components in prototype

• Designed and built rotating support stand to study response of prototype as a function of angle in test beam

• Started testing prototype with cosmic rays at BNL

• Preparing for beam test at Fermilab in February 2014

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 3

EMCAL Tilted Plate Configuration(Flat plates - No Accordion)

A.Kiselev

2 mm W + 1 mm fiber 1 mm W + 1 mm fiber

Energy Resolution vs Tilt Angle

Conclusion: 1mm/1mm sampling reduces dependence on tilt angle and improves performance

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 4

Tilted Plate vs Accordion• Tilted flat plates and accordion strive to accomplish the

same thing: improve longitudinal sampling and prevent channeling

• Accordion is actually more desirable since it keeps the shower more compact in the transverse dimension

• Problem with W-SciFi accordion is that it is difficult to make a “high frequency” accordion with fibers (must respect bending radius) and it is difficult to control the shape and tolerances of accordion W plates

• Optimum may be a combination of a slight accordion plus a small tilt angle

• Decided to build current prototype with flats plates

• Would still like to pursue accordion W plates with THP

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 5

New EMCAL Prototype Assembly

Epoxy is applied to 2 tungsten plates

Twelve sandwiches are glued together to form a module

Fibers are assembled into frames Plates and fiber layer are glued together under vacuum to form a

“sandwich”

Finished W-SciFi sandwichSandwich is cured under weight and vacuum

2 x 0.5 mm flat W plates, 1 mm fibers, rear spacer for tapering

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 6

Absorber Stack

Stack of 7 tower modules (not yet glued) Readout has 7x7 optically separated towers

X0 ~ 7 mm RM ~ 2 cm

Readout end of module is potted with white reflecting epoxy. Other end is

covered with 3M ESR reflector

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 7

Light Collection Cavities

Row of 7 cavities for testing SiPM placement

Seven rows of seven cavities are mounted to a frame and readout boards are connected at the back

Inside of cavities is coated with white reflector

8C.Woody, EIC Detector R&D Committee Meeting, 1/13/14

Light Collection Efficiency

S. Stoll

relative efficiency map of a tapered 27x25x50mm printed cavity, 1 SiPM ~20deg on the dome of the cavity, Hamamatsu 3mm2 SiPMs. readout surface has white painted background

mm

0 3 6 9 12 15 18 21 24 27

mm

0

3

6

9

12

15

18

21

24

0 1 2 3 4 5 6 7 8

mean 4.69MAX 6.25min 3.67MAX/min 1.70

Average efficiency = 4.7%Max/Min ratio = 1.7

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 9

Light YieldLight output from absorber stack was measured with cosmic rays for one tower module (12 scintillator layers) with directly coupled PMT

EMCal tower read out with unmasked R2059 2" pmtCosmic ray trigger (scintillators above and below module).Finished module #1 with RMF reflector on front surface.

adc channels

0 500 1000 1500

coun

ts

0

20

40

60

80

100

datafitpeak: 541 ch

Light yield from stack = 600 g/MeV (energy deposited in scintillator)

Sampling fraction of 6.4% 38,400 g/GeV in calorimeter

Light collection efficiency of 4.7% from cavities 1800 g/GeV

SiPM PDE = 25% 450 p.e./GeV ~ 5% contribution to energy resolution from photon statistics

Light Yield = 600 g/MeV

S. Stoll

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 10

LED Calibration System

Splitter fixture for testing uniformity and efficiency of 1x7 splitters

1x7 splitter for distribution of calibration light to light collection cells

LEDPulser

PIN diodefor monitoring LED

1:7 split1:8 splitSiPM

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 11

Final Assembly

Assembly of absorber stack and readout

module into rotation stand

Testing EMCAL Prototype with Cosmic Rays

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 12

EMCAL prototype being tested with cosmic rays in the Physics High Bay

Digitized cosmic ray pulses

Pulse height distribution

~ 30 MeV(w/higher gain preamp)

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 13

sPHENIX HCAL Prototype

sPHENIX HCAL prototype being assembled in the Physics High Bay

Will be tested with EMCAL prototype in beam test at Fermilab

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 14

Fermilab Beam Test

Test of combined EMCAL and HCAL prototypes at Fermilab in Feb 2014 (sPHENIX 2/5-2/25, STAR 2/26-3/18)

sPHENIXHCAL sPHENIX

EMCAL

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 15

Future R&D Plans Test 7x7 prototype in test beam at Fermilab (electrons up to ~ 8 GeV) Test 7x7 prototype in test beam at SLAC to obtain better measurement

of energy resolution (electrons up to ~ 15 GeV) Continue development of thin W plates with THP

• Produce larger plates (~ 1 m) and determine achievable tolerances• Determine if it is possible/cost effective to produce tapered plates• Determine if it is possible/cost effective to produce accordion

shaped plates Build large scale (~ 1m long) prototype module

• Develop technique for assembly aimed at industrialized process Test new SiPMs from Hamamatsu Continue development of readout system and electronics

C.Woody, EIC Detector R&D Committee Meeting, 1/13/14 16

Budget for Future R&D Plans

Item Year 3Materials and supplies 10Additional SiPMs 5Readout electronics development 10Technical support and designer 10R&D on W plates with THP 40Test beam (SLAC) 15Total Direct 90Overhead (50%) 45Total (including overhead) 135

We are not requesting Year 3 funding at this time but we will request/need additional funding in May/June