Muon Detector Systems - Boston University...
42
Muon Detector Systems John M. Butler Boston University & Darien Wood Northeastern University
Transcript of Muon Detector Systems - Boston University...
Muo
n D
etec
tor S
yste
ms
John
M. B
utle
rB
osto
n U
nive
rsity
&D
arie
n W
ood
Nor
thea
ster
n U
nive
rsity
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
2
Out
line
•W
hy M
uons
Mat
ter
•M
uon
Det
ecto
r Sys
tem
s–
Bas
ic P
rinci
ples
–R
eal E
xam
ples
•B
ackg
roun
ds–
Had
ron
Pun
ch-th
roug
h–
Low
E P
artic
les
–C
osm
ic R
ays
•D
esig
n C
onsi
dera
tions
–M
omen
tum
Res
olut
ion
•M
ultip
le S
catte
ring
•P
ositi
on M
easu
rem
ent
–G
eom
etric
Acc
epta
nce
•D
esig
n C
halle
nge
•C
avea
ts–
Lim
it ex
ampl
es to
cur
rent
and
fu
ture
had
ron
collid
er d
etec
tors
: C
DF,
DØ
, ATL
AS
, CM
S–
I will
be a
bit
DØ
-cen
tric,
ap
olog
ies
in a
dvan
ce–
Man
y to
pics
will
be s
kipp
ed•
Drif
t cha
mbe
r ope
ratio
n (B
ecke
r, la
st y
ear)
•D
rift c
ham
ber a
ging
•D
etai
ls o
f ene
rgy
loss
(F
ishe
r, th
is y
ear;
Ahl
en, l
ast y
ear)
•Fr
ont e
nd e
lect
roni
cs
(Oliv
er, t
his
year
)•
Det
ails
on
trigg
erin
g•
…
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
3
Des
ign
Cha
lleng
e ak
a “H
omew
ork”
•B
rief i
ntro
her
e, d
etai
ls a
t the
end
•Y
our j
ob is
to d
esig
n a
“fast
er, b
ette
r, ch
eape
r”
dete
ctor
to d
isco
ver t
he H
iggs
at t
he L
HC
in th
e go
lden
mod
e H
Z
Z µ+
µ−µ+
µ−
•Y
our d
etec
tor w
ill b
e an
“iro
n ba
ll”de
sign
–Ju
st a
muo
n sy
stem
–D
on’t
mea
sure
ele
ctro
ns, j
ets,
mis
sing
ET,
etc
.•
Opt
imiz
atio
n: y
our d
etec
tor m
ust h
ave
suffi
cien
t H
iggs
mas
s re
solu
tion
to c
laim
dis
cove
ry w
hile
m
inim
izin
g th
e ch
anne
l cou
nt (i
.e. t
he c
ost)
•P
rese
ntat
ions
of p
ropo
sals
dur
ing
the
Wed
nesd
ay
sess
ion
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
4
Goo
gle
“iron
bal
l det
ecto
r” an
d…19
75 P
EP
Sum
mer
Stu
dy
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
5
Why
Muo
ns M
atte
r
•H
igh
ener
gy le
pton
s ha
ve
been
a h
ighl
y pr
oduc
tive
way
to
find
new
par
ticle
s•
The
J/ψ
, τ, Y
, W, Z
, and
to
p qu
ark
disc
over
ies
all
relie
d on
muo
ns•
No
high
ene
rgy
muo
ns in
the
initi
al s
tate
–S
igna
ture
for i
nter
estin
g ph
ysic
s–
The
goal
sho
uld
be to
get
th
em a
ll on
tape
!
•P
hysi
cs to
pics
at t
he
Teva
tron
and
LHC
that
use
m
uons
–H
eavy
flav
ors
(b, c
)–
Top
quar
k ph
ysic
s–
Ele
ctro
wea
k–
Sea
rche
s fo
r new
ph
enom
ena:
Hig
gs,
SU
SY
…•
b-ta
ggin
g vi
a b
µ ν
c•
Rel
ativ
ely
easy
to tr
igge
r on
and
ID m
uons
but
…re
quire
s a
very
larg
ede
tect
or s
yste
m
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
6
Muo
n P
rope
rties
•Fr
om th
e P
artic
le D
ata
Gro
up–
Mas
s =
105.
7 M
eV/c
2
–P
rope
r life
time
= 2.
2 µs
•H
owev
er, i
n ha
dron
col
lider
exp
erim
ents
–
Muo
ns a
re s
tabl
e pa
rticl
es–
v ≈
c•
Pen
etra
ting
–D
epos
it on
ly m
inim
um io
nizi
ng e
nerg
y in
det
ecto
r mat
eria
l (u
p to
the
criti
cal e
nerg
y, m
ore
late
r)–
Onl
y pa
rticl
es to
esc
ape
a ha
dron
col
lider
det
ecto
r are
m
uons
and
neu
trino
s
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
7
Pur
pose
s of
Muo
n D
etec
tor S
yste
ms
•Id
entif
y m
uons
–at
the
trigg
er le
vel a
nd o
fflin
e•
Opt
iona
lly –
mea
sure
the
muo
n’s
mom
entu
m•
Opt
iona
lly –
act a
s a
“tail
catc
her”
for m
easu
ring
the
ener
gy th
at le
aks
out o
f the
cal
orim
eter
from
ver
y hi
gh e
nerg
y je
ts
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
8
Ele
men
ts o
f Muo
n D
etec
tion
track
erca
lorim
eter
Muo
n m
agne
tM
easu
re p
inin
so
leno
id fi
eld
Det
ecto
r Lay
er –
mul
tiple
pla
nes
of(a
) coo
rdin
ate
mea
sure
men
ts(b
) fas
t cou
nter
s
Mea
sure
pou
tus
ing
(a) t
oroi
d fie
ldso
lid o
r air
core
or (b
) sol
enoi
d re
turn
fiel
d
Abs
orb
hadr
ons
Elo
ssfro
m io
niza
tion
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
9
Rea
l Muo
n S
yste
ms:
CD
F
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
10
•N
o p o
utm
easu
rem
ent
•D
rift c
ham
bers
–C
entra
l: 2-
laye
rs (8
pl
anes
), 3.
4k c
h–
Ext
ensi
on: 1
-laye
r (4
plan
es),
2.2k
ch
–In
term
edia
te: 1
-laye
r (4
pla
nes)
, 1.7
k ch
•S
cint
illat
or–
Cen
tral:
1-la
yer,
270
ch–
Ext
ensi
on: 2
-laye
r, 32
0 ch
–In
term
edia
te: 1
-laye
r, 86
0 ch
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
11
Rea
l Muo
n S
yste
ms:
DØ
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
12
•Fe
Tor
oid
–2
T•
Drif
t Cha
mbe
rs–
Cen
tral:
3-la
yers
(1
0 pl
anes
), 6.
8k c
h–
Forw
ard:
3-la
yers
(1
0 pl
anes
), 50
k ch
•S
cint
illat
or–
Cen
tral:
2-la
yers
, 99
0 ch
–Fo
rwar
d: 3
-laye
rs,
4.8k
ch
•E
xten
sive
shi
eldi
ng
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
13
Rea
l Muo
n S
yste
ms:
ATL
AS
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
14
•A
ir-co
re T
oroi
ds•
Drif
t Cha
mbe
rs–
3-la
yers
(6/8
pla
nes/
laye
r),
370k
ch
–30
µm
rela
tive
cham
ber
alig
nmen
t•
Cen
tral R
PC
s: 3
-laye
rs
•Th
in G
ap C
ham
bers
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
15
Rea
l Muo
n S
yste
ms:
CM
S
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
16
•R
etur
n fie
ld fr
om s
olen
oid
–2
T•
Cen
tral:
Drif
t Cha
mbe
rs–
4-la
yers
(32+
12 p
lane
s), 2
00k
ch•
Forw
ard:
Cat
hode
Stri
p C
ham
bers
–4-
laye
rs (2
4 pl
anes
), 40
0k c
h•
RP
Cs:
4-la
yers
(6 p
lane
s),
155k
ch
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
17
Mag
nets
•S
olid
Cor
e To
roid
–Iro
n–
B ~
2 T
–Fu
rther
filte
rs h
adro
ns–
Mul
tiple
sca
tterin
g in
Fe
will
lim
it p o
utre
solu
tion
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
18
Mag
nets
•A
ir C
ore
Toro
id–
B ~
0.3
-1 T
, ∫B
dl ~
3-9
Tm
in A
TLA
S–
Allo
ws
prec
isio
n m
easu
rem
ent o
f pou
t
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
19
Det
ecto
r Lay
er
•C
oord
inat
e M
easu
rem
ent
–D
rift C
ham
bers
, cat
hode
st
rip c
ham
bers
–W
ire p
itch
~1-1
0 cm
per
p. to
µ
traje
ctor
y–
Res
olut
ions
rang
e fro
m
80-7
00 µ
m, o
ne li
mit
on
mom
entu
m re
solu
tion
–In
tegr
ate
~few
bea
m
cros
sing
s
CM
S
ATL
AS
DØ
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
20
Det
ecto
r Lay
er
•Fa
st T
rigge
r Cou
nter
s–
Sci
ntilla
tor +
PM
Ts,
Res
istiv
e P
late
Cha
mbe
rs
(RP
Cs)
–R
esol
utio
n ~1
-2 n
s–
Tag
beam
cro
ssin
g in
tri
gger
–R
educ
e ba
ckgr
ound
s
DØ
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
21
Sou
rces
of S
igna
ls in
Muo
n S
yste
ms
•P
hysi
cs P
roce
sses
, Pro
mpt
M
uons
–H
eavy
flav
ors:
c a
nd b
qu
arks
–W
, Z d
ecay
s–
Top
quar
ks–
Hig
gs, n
ew p
heno
men
a•
Bac
kgro
unds
–pi
on/k
aon
deca
ys in
flig
ht–
Had
ron
punc
h-th
roug
h–
Bea
m H
alo
–B
acks
catte
r–
Cos
mic
Ray
s–
Ran
dom
coi
ncid
ence
s
ATL
AS
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
22
Pro
mpt
Muo
n S
igna
ture
Muo
n m
agne
t
track
erca
lorim
eter
p out
p in
Rea
l muo
n
p in
≈p o
ut +
Elo
ss
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
23
Ene
rgy
Loss
of M
uons
in M
atte
rP
DG
Muo
ns a
re ty
pica
lly “m
ips”
in th
em
omen
tum
rang
e of
inte
rest
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
24
Ene
rgy
Loss
of M
uons
in M
atte
rP
DG
Ver
y hi
gh e
nerg
y m
uons
sho
wer
like
ele
ctro
nsR
adia
tive
loss
es d
omin
ate
abov
e th
e cr
itica
l ene
rgy
Eµc
Eµc
~ 35
0 G
eV fo
r muo
ns in
Fe
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
25
Mul
tiple
Cou
lom
b S
catte
ring
•M
uons
trav
ersi
ng m
ater
ial a
re d
efle
cted
from
thei
r orig
inal
tra
ject
ory
by m
ultip
le s
mal
l-ang
le C
oulo
mb
scat
ters
off
nucl
ei•
y pla
nean
d θ p
lane
are
~ G
auss
ian
dist
ribut
ed
PD
G
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
26
Bac
kgro
und
–P
unch
-thro
ugh
and
Dec
ay-in
-Flig
ht
track
erca
lorim
eter
Muo
n m
agne
t
p out
p in
hadr
on
p in >>
pou
t + E
loss
Out
er p
unch
-thro
ugh/
deca
y tra
ck p
oint
s ba
ck to
pa
rent
had
ron,
but
mom
enta
do
not m
atch
.
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
27
Bac
kgro
und:
Had
ron
Pun
ch-th
roug
h•
Def
ine
“pun
ch-th
roug
h” a
s pa
rticl
es fr
om la
te-d
evel
opin
g ha
dron
sho
wer
s th
at g
et in
to th
e µ
syst
em•
“Sne
ak-th
roug
h” –
prob
abili
ty fo
r a
hadr
on to
not
inte
ract
afte
r pen
etra
ting
a di
stan
ce x
, ty
pica
lly v
ery
smal
l
•M
inim
ize
punc
h-th
ough
by
–M
ater
ial a
s m
easu
red
in
nucl
ear i
nter
actio
n le
ngth
s λ I
•“B
est µ
ID to
ol is
a m
eter
of
ste
el”
–G
ood
track
mat
ches
con
sist
ent
with
ms
unce
rtain
ty•
Pro
b ~1
0-3
–10
-4in
DØ
NIM
A24
4, 3
56 (1
986)
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
28
Bac
kgro
und:
Had
ron
Pun
ch-th
roug
h
CD
FP
unch
-thro
ugh
is a
pro
blem
for µ
ID a
nd tr
igge
ring
ATL
AS
DØ
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
29
Bac
kgro
und:
Bea
m H
alo
Muo
n m
agne
tca
lorim
eter
track
er
p out
p in
p in
? p o
ut +
Elo
ss
Goo
d tim
ing
(sci
ntill
ator
, RP
C) a
nd tu
nnel
sh
ield
ing
can
get r
id o
f mos
t of t
hese
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
30
Bac
ksca
tter B
ackg
roun
d
•R
educ
e so
urce
: con
ical
bea
m p
ipe/
calo
rimet
er:
colli
sion
s
Low
βqu
ad/s
hiel
ding
Forw
ard
calo
rimet
er
•Shi
eld
arou
nd q
uads
•Rej
ect r
emai
ning
ba
cksc
atte
r with
tim
ing
Or e
lse…
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
31
Hadrons EM particlesE
ffect
of S
hiel
ding
With
Shi
eldi
ngN
o S
hiel
ding
50 c
m F
e –
h &
EM
12 c
m p
olye
thyl
ene
–n
5 cm
Pb
–ga
mm
as
Shi
eld
redu
ced
rate
by
fact
or o
f 100
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
32
Bac
kgro
und:
Cos
mic
Ray
Muo
ns
•C
osm
ic ra
y m
uons
arr
ival
tim
es a
re u
ncor
rela
ted
with
bea
m
cros
sing
s fla
t bac
kgro
und
in ti
me
–C
ut o
n tig
ht ti
min
g w
indo
w a
roun
d t =
0 u
sing
fast
cou
nter
s•
Als
o re
quire
trac
k po
int t
o th
e pr
imar
y ve
rtex
allt
ime
En
trie
s 1
3604
8
Mea
n
5.3
92
RM
S
15.
04
Sci
nti
llato
r ti
me
(ns)
-20
-10
010
2030
4050
6070
80
Number of events
0
2000
4000
6000
8000
1000
0
1200
0
1400
0
1600
0
allt
ime
En
trie
s 1
3604
8
Mea
n
5.3
92
RM
S
15.
04
Mu
on
Sci
nti
llato
r T
imes
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
33
Mom
entu
m R
esol
utio
n
•Tw
o di
stin
ct c
ontri
butio
ns to
m
omen
tum
reso
lutio
n–
Mul
tiple
Cou
lom
b S
catte
ring
in d
etec
tor m
ater
ial (
ms)
–Fi
nite
pos
ition
mea
sure
men
t re
solu
tion
(res)
–A
ssum
e θ
wel
l mea
sure
d,
so δ
θis
neg
ligib
le–
Sur
vey
is a
noth
er im
porta
nt
cont
ribut
ion
•C
onve
ntio
nal t
o qu
ote
δp/p
bu
t mea
sure
men
t is
Gau
ssia
n in
1/p
, not
p
0.00
0.10
0.20
0.30
0.40
0.50
0.60
010
2030
4050
6070
8090
100
p (G
eV/c
)
sigma(p)/p
ms
tota
l
res
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
34
Mom
entu
m R
esol
utio
n
•M
ultip
le S
catte
ring
cont
ribut
ion
depe
nds
on–
Mat
eria
l thr
ough
the
“rad
iatio
n le
ngth
” X0
•X
0=
1.76
cm
for F
e–
Pat
h le
ngth
L′i
n m
ater
ial
–B
fiel
d–
Uni
ts a
re G
eV/c
, Tes
la,
met
er•
For e
xam
ple,
in D
Ø
L′=
1m @
nor
mal
inci
denc
e B
= 2T
so th
e m
ser
ror i
s ~2
0%
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
35
Mom
entu
m R
esol
utio
n
s
RR
•S
tart
with
a s
impl
e ca
se•
Ass
ume
–U
nifo
rm B
fiel
d in
z-d
irect
ion
–sm
all θ
–L
is p
roje
cted
leng
th o
f tra
ck
onto
ben
ding
pla
ne•
To m
easu
re p
T, m
easu
re th
e sa
gitta
s–
3 eq
uidi
stan
t mea
sure
men
ts
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
36
Mom
entu
m R
esol
utio
n
s
RR
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
37
Mom
entu
m R
esol
utio
n
•M
ake
mor
e m
easu
rem
ents
!G
luck
ster
n, N
IM 2
4, 3
81 (1
963)
–N
equ
idis
tant
m
easu
rem
ents
–
N >
> 3
–S
ame
δy fo
r eac
h–
Uni
form
B fi
eld
•To
impr
ove
reso
lutio
n w
ith
3-m
easu
rem
ent s
yste
m–
Incr
ease
L–
Incr
ease
B–
Dec
reas
e δy
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
38
Mom
entu
m R
esol
utio
n
•C
an w
in fu
rther
on
reso
lutio
n by
–
Arr
angi
ng N
mea
sure
men
ts li
ke th
e 3-
mea
sure
men
t cas
e•
Clu
ster
ing
mea
sure
men
ts a
lso
nece
ssar
y fo
r trig
ger
–P
rimar
y ve
rtex
cons
train
t red
uces
reso
lutio
n by
fa
ctor
of ~
√2 to
2
•A
lso
by re
duci
ng δ
y bu
t…–
#cha
nnel
s ~
1/y c
ell~
$$$
–Fo
r our
exe
rcis
e, a
ssum
e a
PW
C-ty
pe re
solu
tion
–In
pra
ctic
e, d
o be
tter u
sing
drif
t cha
mbe
rs
(see
Bec
ker’s
talk
from
last
yea
r)
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
39
Geo
met
ric C
over
age
•Im
porta
nt d
esig
n ch
oice
driv
en b
y ph
ysic
s an
d co
st•
In h
adro
n co
llider
s, th
e na
tura
l coo
rdin
ates
are
not
r, φ
, θbu
t r, φ
, η•
Why
pse
udo-
rapi
dity
η?
Lig
ht p
artic
les
are
prod
uced
suc
h th
at
6o3
15o
2
40o
1
90o
0
θη
√s=
2 Te
V @
Tev
atro
n√s
= 14
TeV
@ L
HC
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
40
Geo
met
ric C
over
age
•To
ach
ieve
~co
nsta
nt ra
te in
eac
h de
tect
or e
lem
ent,
cons
tant
∆η
× ∆
φse
gmen
tatio
n is
pre
ferre
d. F
or e
xam
ple,
DØ
pix
el
coun
ters
hav
e se
gmen
tatio
n of
0.1
×4.
5o
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
41
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.
Geo
met
ric C
over
age
•In
pra
ctic
e, th
e m
axim
um η
is s
elec
ted
to h
ave
good
ac
cept
ance
for µ
’s fr
om
“hea
vy” p
artic
les
•Fo
r exa
mpl
e, a
t the
Tev
atro
n η m
ax~
2 is
suf
ficie
nt fo
r top
Effi
cien
cy
2.4
CM
S
2.7
ATL
AS
2.0
DØ
1.5
CD
F
η max
Exp
erim
ent
John
M. B
utle
rN
EPPS
R, 1
8 Au
gust
2003
42
Sum
mar
y
Muo
ns w
ent f
rom
“Who
ord
ered
that
?” –
I.I. R
abi
to b
eing
esse
ntia
l to
collid
er p
hysi
cs
Muo
n de
tect
or s
yste
ms
are
now
stan
dard
com
pone
nts
of
collid
er d
etec
tors
And
now
for y
our h
omew
ork…
