Overview of GRETINA

I-Yang Lee

Lawrence Berkeley National Laboratory

GRETINA Auxiliary Detector WorkshopWashington University

28 - 29 January 2006

Outline

Status Mechanical interface Data acquisition interface Summary

Highlight of recent achievements

Obtained CD2A/CD3A approval, 6/16/05 Purchase 3 detectors

Awarded detector contract 9/30/05 1 detector, with options for 7 total

Published prototype II in-beam test results Obtained 2 mm position resolution

Refurbished prototype II detector With 18 cold and 18 warm FETs

Tested prototype III detector module

Signal decomposition meeting

Status of mechanical structure

Completed conceptual design, except for the quarter sphere.

Carried out finite element analyses to ensure the required rigidity of the support structure.

Studying installation at potential sites. Fabrication drawings for hexapod are being made. Schedule to complete 3/31/06

Installation at potential sites• Cave 4C, 88” Cyclotron LBNL• FMA, ATLAS ANL• RMS, HRIBF ORNL• S800, NSCL MSU

Collected 3D drawings Visited MSU, ANL and ORNL Challenges :

- Position GRETINA at the ideal location of the spectrographs.- Detector at forward angle at NSCL

Proposed a 4-ring design Modification to fit ANL and ORNL

Detector angles: 31.7º (5 positions), 58.3º (4), 90º (8), and 121.7º (4)

Target chamber

∎ Target to Ge = 17.8 cm∎ Inner radius = 17 cm ∎ Cord radius = 16 cm

6 Ports∎ Beam in ∎ Beam out ∎ Target/cable x2∎ Target port at 90º ∎ Viewing port

Electronics status

Completed electronics requirement document Studied the Eurisys pre-amplifier. Completed the grounding and shielding design. Tested selected signal cables, and connectors. Decided to implement trigger serializers using

FPGAs and standard protocols

Detector analog signals Digitizer

Zo/2

Cable: twisted pairs

C

Twisted pair with shielding

Drain wire for pairs

Cable drain wire

Cable shielding

Jacket

Computing system status

Completed Computing system requirement document

Integrated software to perform end-to-end test– Detector signal crystal event building signal

decomposition global event building tracking disk

Improved data acquisition software– Eliminated errors– New run control system

Design and purchased prototype computer cluster (with 8 nodes)

Data Acquisition System

Signal digitizer Network switch Workstations

Data Acquisition System Schematic

Aux. Det. Trigger

Global TriggerModule

SignalDigitizers

Local TriggerModule

NetworkSwitch

Processing Farm

28 Crystals

Data Storage

2.2 MB/s

Aux. Det. Data

66 MB/s

75 dual Processors

Workstations, Servers

6.9 MB/s

2.3 MB/s + Aux. Det. Data

Trigger/timing system Processing farm Data storage

Data Acquisition

GRETINA Auxiliary Detector

Trigger Each segment generates and receives trigger

FPGA based trigger unit

Accept and provide multiple trigger types

Timing Each segment has LED and CFD time stamps

At least one time stamp per event

Readout Buffered readout for each module

Two-level event building, crystal and global

Analog signalsDigitized data streamsEthernet packets

Auxiliary detector interface Trigger in/out Time stamp Data read out

Interface options

Analog signals Digitized data streams Ethernet packets

Data Acquisition System Schematic

Aux. Det. Trigger

Global TriggerModule

SignalDigitizers

Local TriggerModule

NetworkSwitch

Time

Aux. Detector Interface crate

Tim

e stamp

Aux. Detector crates

FE

RA

CA

MA

C

TDC

ADC

Clock

Ethernet packets

Analog signal

FERA data stream

Acquisition interface options

Additional hardware and software are not funded currently

Options Signal Additional hardware Additional software

Preamp signals Pulse digitizer

VME crate

VME controller

NONE

Analog signal

Shaped signals

Trigger

time

VME ADC, TDC

Time stamp module

VME crate

VME controller

Module control

Module readout

Digitized data stream

FERA

Trigger

time

FERA interface module

Time stamp module

VME crate

VME controller

Module control

Module readout

Ethernet packet

Ethernet packets

Trigger

time

NONE

NONE

Auxiliary detector interfacing issues

• Mechanical– Space inside chamber– Vacuum– Cable and target ports– Interference with external structure and

detectors

• Data acquisition– Number of allowed interface options– Additional hardware needs– Additional software efforts

New auxiliary/external detectors

• Super-CHICO

ScheduleWBS Task Name

1 GRETINA

1.1 Mechanical

1.1.2 Design

1.1.3 Production

1.2 Detector Module

1.2.1 Purchasing

1.2.2 Test/Characterize Module 1

1.2.3 Test/Characterize Rest of Modules

1.3 Electronics

1.3.2 Prototype

1.3.3 Production

1.4 Computing Systems

1.4.2 Prototype

1.4.3 Production

1.5 System Assembly

1.5.1 Prototype

1.5.2 Production

1.6 Project Management

1.7 Environment and Safety

1.12 Level 1 Milestones: Critical Decisions CD1 CD2/3A CD2/3B CD4

Complete test proc. and apparatus

Award module contract Exercise option last module

Complete mechanical subsystem

Complete test DSP module

Start production DSP module

Award computer farm contract

Ready for prototype assembly Ready for final assembly

CD0

3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 42003 2004 2005 2006 2007 2008 2009 2010 2011

Complete test/char. module

Complete design/draw. support structure

January 2006

Summary GRETINA is on budget and on schedule. In 2006 design work of all systems will be in

progress Process of design interface with auxiliary detector

Developed requirement documents Working with potential sites and working groups Make decisions on design Designs

Auxiliary/external detectors are essential Many challenges and opportunities for auxiliary

detectors This workshop is an important step in advancing

the state-of-the-art

FMA Efficiency 48Ca + 124Sn 200 MeV Target 1 mg/cm2

Acceptance 5 cm Dia.

0

20

40

60

80

100

120

30 40 50 60 70 80 90 100

Distance (cm)

Eff

icie

nc

y (

%)

4n2p2nalpha 2n

S800 Efficiency

RMS Efficiency

• Nominal target to quad distance = 72 cm

• Acceptance angle= ± 30 mr (H), ± 100 mr (V)

0

0.2

0.4

0.6

0.8

1

1.2

70 80 90 100 110 120 130 140

Distance (cm)

So

lid

an

gle

fra

ctio

n