Radiation safety@isac saferib workshop cern oct 30 nov 1 2002
Download
1 / 51

Radiation. Safety@ISAC SAFERIB Workshop CERN, Oct.30-Nov.1, 2002 - PowerPoint PPT Presentation


  • 117 Views
  • Uploaded on
  • Presentation posted in: General

Radiation. Safety@ISAC SAFERIB Workshop CERN, Oct.30-Nov.1, 2002. L. Moritz TRIUMF 4004 Wesbrook Mall Vancouver, B.C. V6T2A3 Lutz.moritz@triumf.ca. Overview. Short description of ISAC Shielding (tools and verification) Activation (yields and distribution) Target handling

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha

Download Presentation

Radiation. Safety@ISAC SAFERIB Workshop CERN, Oct.30-Nov.1, 2002

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Radiation.Safety@ISACSAFERIB WorkshopCERN, Oct.30-Nov.1, 2002

L. Moritz

TRIUMF

4004 Wesbrook Mall Vancouver, B.C. V6T2A3

Lutz.moritz@triumf.ca


Overview

  • Short description of ISAC

  • Shielding (tools and verification)

  • Activation (yields and distribution)

  • Target handling

  • Contamination control

  • Experience and plans for future


ISAC Parameters

Reference Design:

100 A of 500 MeV protons on

95 g cm-2 UC2

Authorization:

100 A of 500 MeV protons on targets

Z  82

Application for targets with Z > 82 in preparation

Ottawa


Targets (to September 2002)

Test only


ISAC at TRIUMF

http://www.triumf.ca/isac/is9-00-t.jpg


ISAC Experimental Hall


ISAC-II (2005)


ISAC Target Stations

RIB

Initial Installation:

West Target Station

Installation 2002: East Target Station

500 MeV Protons


Shielding

  • Bulk Shielding: Point source, line-of-sight attenuation

  • Complicated geometries: FLUKA

  • Verification: MCNP, LCS


Point Source, Line-of-sight Attenuation of Prompt Radiation Field

Nuclear interaction probability

Geometry factor

High-energy neutron yield

Exponential Attenuation

Angular dependence


Parameters fn(Ep), h0,, 

Nuclear interaction probability, fn

Source term, h0

m=0.8

Angular dependence, 

Attenuation

length, 


Test: 500 MeV Proton Beam Stop

1.8 m

2.9 m


ISAC Target Shielding (Plan)

Concrete

(low Na)

Radioactive Ion beam

Concrete

Steel

Slits

A

Cu Beam dump

A’

Target

Proton beam


0

1m

ISAC Target/ion Source Shielding

concrete & steel

(Section AA’)

Service space

concrete

vacuum seals

steel

steel

steel

target

ion beam

recycled steel


FLUKA simulation

Streaming Through Pre-separator Maze

Target: 50 g cm-2 UC2

Ep = 500 MeV

Ip = 100 mA


Before

Pre-separator Maze

Added shielding

After


ISAC Target Module


Target Module Service Ducts

Target/Ion Source


Sv/h

Streaming Through Target Vacuum Exhaust Ducts

Concrete-

steel

Air

Target: 50 g cm-2 UC2

Ep = 500 MeV

Ip = 100 mA

steel

p


Streaming Through Ducts

Concrete-

steel

Air


Composition of Top Shield


Sv/h

1000

350

400

200

105

100

10

140

170

200

115

1

Radiation Fields above Target

Andersson-Braun Measurement

100 A on Mo Target Test


Activation

  • Experimental Cross-sections

  • Silberberg & Tsao

  • FLUKA, LAHET, MCNPX

  • ORIGEN


238U(p,x) Cross Section Comparison at 500 MeV

…………

Silberberg & Tsao

LCS

FLUKA

Experimental

Spallation

Fission

Peripheral


Silberberg & Tsao (YIELDX)

500 MeV Protons


FLUKA Simulation (500 MeV protons on UC2 target)

UC2 (5.076 g cm-3)

H2O

p

67 mm

27 mm

Ta

18 cm

p

1.4 cm

UC2 (5.076 g cm-3)


Yields: UC2 target (FLUKA simulation)

18 cm

500 MeV p

1.4 cm

UC2 (5.076 g cm-3)


ORIGEN (build-up and decay)

Beam On

Beam Off


Decays Leading to 210Po

210Po

Long-lived

Not in ORIGEN Library


ISAC Target Handling

Target Maintenance Hall


Maximum g-field Outside ITMH

~10 Sv/h

@ 1 m

1 mSv/h


ISAC Target Servicing:

Hot

Target storage pit

Cells

Target storage pit

Hot

Cells


ISAC target hot cell roof docking mechanism


ISAC target being docked in hot cell


ISAC Hot Cells Before Installation of Windows


View Through ISAC Hot Cell Window


Contamination Control

  • Ventilation System

  • Production of Radioactivity in Air

  • Typical Release Rates

  • Production of Volatile Radioactivity

  • Vacuum Exhaust Handling


Secondary Filters

Primary Filters

Ventilation System

Stack

Air pressure depression

relative to outside

Fan

Standby Fan

Target

Service

Space

Presep.

Cave

Mass

Separator

Room

Experimental

Hall

Services

Hot Cell

Service

Room

Hot Cell

Target Maintenance Hall


Radioactivity Production in Air


Production in Pre-separator Vault

(3000 hours per year, 100mA on 238UC2 target)


Production in Target Service Space

(3000 hours per year, 100 A on 238UC2 target)


Releases to Atmosphere (Gaseous, 2001)


Production of Volatiles

Cl/Ar

b+

Ne

Target

I/Xe

Hg

Rb/Kr

volatiles


MP

Vacuum Exhaust System

MP

TP

TIS

MP

HEPA filter

TP

TP

Exit modules

TP

Operating storage

Charcoal filter

TP

TP

Pre-separator

Secondary

Slits

Primary

MP

TP

Mass-separator

Long-term storage


Releases to Atmosphere (Particulates, 2001)


Experience

  • Contamination Issues

  • Collective Dose


One (!) Contamination Incident(June 2000)

Hot Cell

Target Station

Nb target

1

Ta target

2

No contamination after step 1

Uniform contamination after step 1

No other significant contamination

since June 2000


TRIUMF Collective Dose

So far ISAC has had no significant impact on TRIUMF collective dose

Start of ISAC operation


Future Plans

  • Task Force to pursue licensing for actinide targets

  • Proposed test station to measure yields and transport properties of alpha-emitters

  • Proposed second proton beam line to feed second target station


Conceptual Design of Proposed Test Station


ad
  • Login