3 May 2017

ISOLDE

Physics

Group

Meeting

03/05/2017

Technical

news

• HRS

– Vito

(35Ar)

were

the

main

users

(IS601)

with

1

shift

for

IDS

taking

(17N)

for

calibrations.

– There

was

a

mix

up

when

switching

beam

settings

between

IDS

and

VITO,

which

lead

to

lost

time

at

VITO.

– No

changes

had

been

made

to

target

parameters

when

switching

(as

agreed;

may

need

to

re-use

this

target

for

VITO

later

this

year).

– However,

overlapping

arrays

meant

parameters

were

overwritten/changed.

– In

addition

the

RFQ

settings

could

not

be

recovered

due

to

a

new

software

limit,

which

had

been

installed

earlier

that

day

– This

has

since

been

removed,

but

was

implemented

to

prevent

overheating

of

the

amplifier.

– Tim/Stuart

are

making

a

manual

to

prescribe

the

future

operation.

• GPS

– Proton

scan

took

6.5

hours

due

to

badly

setup

separator;

the

beam

was

poorly

set

up

on

the

horizontal

plane.

– It

was

noticed

that

an

element

had

drifted.

– Fixed/noticed

at

5pm

and

p+

scan

completed,

but

no

yield

measurements

were

possible

due

to

this

delay.

– Independent

HV

trips

on

both

the

target

and

the

line.

No

reason

found

e.g.

no

vacuum

spike,

but

this

has

been

seen

many

times

before.

– Drift

in

magnet

field/voltages

reported

by

IDS.

Tuning

appeared

to

not

be

optimum

and

transmission

drifted

to

10%;

recovered

to

65%.

– The

cause

could

not

be

identified,

but

Timber

will

be

used

to

look

at

the

data.

Data

from

scanners

etc.

not

possible

yet.

Elefteris

is

coding

this

into

the

system.

• REX/HIE

– Bake

out

of

REX

is

finished.

– Cooling

of

cryomodules

has

been

improved,

which

will

lead

to

fewer

trips

during

operation.

• RILIS

– Indium

setup

continuing

for

upcoming

runs

at

IDS

and

CRIS.

• Targets

– #595

worked

well

last

week.

– #597

being

installed

now.

– MEDICIS

monotrack

system

was

used,

meaning

that

the

time

to

change

the

target

was

reduced

from

2

hours

to

only

30

minutes,

and

no

access

was

required

in

the

zone.

Physics

news

• VITO

– β-asymmetry

studies

with

35Ar.

– Motivation

is

fundamental

physics

and

the

Vud

matrix

element.

– Preliminary

studies

searching

for

appropriate

crystal

that

can

operate

at

high

temperatures,

whilst

maintaining

the

polarization

for

a

long

time.

Relaxation

time

vs.

nuclear

lifetime.

– Avoid

low

temperatures

(<100K)

as

much

as

possible

to

prevent

freezing

dirt

onto

the

surface

of

the

crystal.

– Total

of

5

candidate

crystals,

2

measured

in

this

beam

time.

– 1st

crystal

showed

some

asymmetry

at

low

temperatures

(~10K).

– 2nd

crystal

(NaF)

maintained

reasonable

asymmetry

at

room

temperature.

Magnitude

is

10x

more

than

1st

crystal,

but

still

not

huge.

– Polarisation

of

lasers

should

also

be

checked.

• IDS

– 133Sn

being

studied

in

β-decay

of

133In.

Also

had

134In

β-n

decay.

– Motivation

is

the

single-particle

structure

with

one

neutron

outside

of

the

doubly-magic

132Sn

core.

– Chances

to

use

RILIS

lasers

to

make

isomer

selection,

enhancing

population

of

low-spin

or

high-spin

states

in

the

daughter

nucleus.

– Neutron

ToF

spectra

obtained

and

states

have

been

identified.

– Goal

to

make

coincidences

between

neutrons

and

gammas;

analysis

is

ongoing.

– A

lot

of

contamination

on

these

masses

for

Cs:

20

kBq

at

mass

A=133

and

65

kBq

at

mass

A=134

(in

only

8

hours).

T1/2

=

10

yrs

and

2

hrs,

respectively.

IDS

passed

on

this

advice

to

CRIS

for

the

following

run,

which

will

explore

a

similar

region.

• CRIS

– Laser

spectroscopy

of

n-rich

In

isotopes.

– Motivation

is

again

in

the

proximity

to

132Sn

and

shell-closures.

– Everything

beyond

128In

will

be

new

for

laser

spectroscopy.

– Aim

to

measure

charge

radii

and

moments

via

high-resolution

hyperfine

spectra.

A.O.B.

• European

Researcher

Night

– ISOLDE

would

like

to

be

involved,

or

at

least

CERN

would

like

ISOLDE

to

be

involved,

this

year.

It’s

in

September.

– Interest

from

French

speakers

would

be

good

as

much

of

the

audience

will

be

the

local

community

in

the

Meyrin

region.

– If

interested,

contact

Karl

to

discuss

as

the

promotional

material

is

expected

to

be

printed

and

advertised

a

long

time

in

advance.

• Safety

courses

– Nobody

signed

up

for

safety

courses

on

16th

May

yet.

Please

inform

Karl

or

it

will

be

cancelled.

• Operations

team

– New

operator

from

PS

who

will

take

over

piquet

duties

from

Pascal.

His

name

is

Simone

and

he

is

training

and

gathering

experience.

• Setups

– WITCH

will

start

up

in

the

week

of

June

12th.

The

magnet

will

be

ramped

up

for

a

couple

of

days

or

nights

and

should

be

communicated

with

accelerator

people.

– A

new

policy

of

oil-free

pumps

in

the

HIE-ISOLDE

extension

is

to

be

adopted

after

contamination

at

Miniball

last

year.

– Dirty

exhaust

lines

will

be

replaced

before

the

campaign.

• INTC

– LOIs

for

stable

and

long-lived

beams

are

requested

at

the

next

INTC

meeting

in

June.

Minutes

taken

by

LPG

Date

2017-05-03