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Tra
nsve
rse
dyna
mic
s at
y=
0 in
BR
AH
MS
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
A s
tory
of
cent
ralit
y de
pend
ent
pt s
pect
ra o
f ide
ntifi
edch
arge
d ha
dron
sm
easu
red
with
the
BR
AH
MS
expe
rimen
t at
RH
IC
Dat
a fr
om A
uAu
colli
sion
s at
s NN
� 200G
eV
Tra
nsve
rse
dyna
mic
s at
y=
0 in
BR
AH
MS
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
A s
tory
of
cent
ralit
y de
pend
ent
pt s
pect
ra o
f ide
ntifi
edch
arge
d ha
dron
sm
easu
red
with
the
BR
AH
MS
expe
rimen
t at
RH
IC
Bjø
rn H
. Sam
set
PhD
stu
dent
, U
nive
rsity
of O
slo,
Nor
way
Bee
n w
ith B
RA
HM
S fo
r 4
year
s...
Tra
nsve
rse
dyna
mic
s at
y=
0 in
BR
AH
MS
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
A s
tory
of
cent
ralit
y de
pend
ent
pt s
pect
ra o
f ide
ntifi
edch
arge
d ha
dron
sm
easu
red
with
the
BR
AH
MS
expe
rimen
t at
RH
IC
Bjø
rn H
. Sam
set
PhD
stu
dent
, U
nive
rsity
of O
slo,
Nor
way
Bee
n w
ith B
RA
HM
S fo
r 4
year
s...
BR
AH
MS
cra
ter
on M
ercu
ry,
form
ed b
y a
high
ene
rgy
colli
sion
at l
owce
ntra
lity,
plu
s so
me
tran
sver
se fl
ow.
Out
line
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
� The
BR
AH
MS
exp
erim
ent a
t RH
IC
� The
ana
lysi
s -
extra
ctin
g pa
rtic
le y
ield
s fr
om B
RA
HM
S d
ata
� <p t>
and
cen
tral
ity d
ep. o
f dN ch/d
η at
y=
0
� <p t>
and
cen
tral
ity d
ep. o
f ide
ntifi
ed h
adro
n p
t spe
ctra
at y
=0
� Cen
tral
ity d
epen
denc
e of
like
and
unl
ike
part
icle
rat
ios
vs
. pt a
t y=
0
� Con
clus
ions
and
futu
re v
isio
ns
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
The
e
xper
imen
t
a
t
The
BR
AH
MS
col
labo
ratio
nB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
I.G. B
eard
en7 ,
D. B
eavi
s1 , C
. Bes
liu10
, Y. B
lyak
hman
6 , J.
Brz
ychc
zyk4 ,
B. B
udic
k6 ,H
. Bø
ggild
7 ,C
. Cha
sman
1 , C
. H. C
hris
tens
en7 ,
P. C
hris
tians
en7 ,
J.C
ibor
4 , R
.Deb
be1 ,
J. J
. Gaa
rdhø
je7 ,M. G
erm
inar
io7 ,
K. G
roto
wsk
i4 , K
. Hag
el8 ,
O. H
anse
n7 , A
.K. H
olm
e12, E
. Eng
er12
, H. I
to11
, E. J
acob
sen7 ,
A. J
ipa10
, J. I
. Jor
dre10
, F. J
undt
2,
C.E
.Jø
rgen
sen7 ,
T. K
eutg
en9 ,
E. J
. Kim
5 , T
. Koz
ik3 ,
T.M
.Lar
sen12
, J. H
. Lee
1 , Y
. K.L
ee5 ,
S. L
inda
l12, G
. Lø
vhø
jden
12, Z
. Maj
ka3 ,
A. M
akee
v8 , B
. McB
reen
1 , M
. Mik
kels
en12
,M
. Mur
ray
8 , J.
Nat
owitz
8 , B
.S.N
iels
en7 ,
K. O
lcha
nski
1 , D
. Oue
rdan
e7 , R
.Pla
neta4 ,
F. R
ami2 ,
D. R
oehr
ich9 ,
B. H
. Sam
set12, S
. J. S
ande
rs11, I
. S. S
gura
10, R
.A.S
heet
z1, Z
.Sos
in3 , P
. Sta
szel7 ,
T.S
. Tve
ter12
, F.V
ideb
æk1 ,
R. W
ada8 a
nd A
.Wie
loch
3
1 Bro
okha
ven
Nat
iona
l Lab
orat
ory,
US
A, 2 IR
eS a
nd U
nive
rsité
Lou
is P
aste
ur, S
tras
bour
g, F
ranc
e3 J
agie
lloni
an U
nive
rsity
, Cra
cow
, Pol
and,
4 Inst
itute
of N
ucle
ar P
hysi
cs, C
raco
w, P
olan
d5 J
ohns
Hop
kins
Uni
vers
ity, B
altim
ore,
US
A, 6N
ew Y
ork
Uni
vers
ity, U
SA
7 Nie
ls B
ohr
Inst
itute
, Ble
gdam
svej
17,
Uni
vers
ity o
f Cop
enha
gen,
Den
mar
k8 T
exas
A&
M U
nive
rsity
, Col
lege
Sta
tion.
US
A, 9 U
nive
rsity
of B
erge
n, N
orw
ay
10U
nive
rsity
of B
ucha
rest
, Rom
ania
, 11U
nive
rsity
of K
ansa
s, L
awre
nce,
US
A
12 U
nive
rsity
of O
slo
Nor
way
The
BR
AH
MS
exp
erim
ent
Set
up u
sed
for
AuA
u da
ta in
200
1B
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
BR
AH
MS
cov
erag
e fo
r th
eA
uAu
run
of 2
001
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
MR
SF
S
25 G
eV/c
4o
2.3o (
min
)
90o
Cov
erag
e of
the
y-pt
pla
ne is
ach
ieve
dby
rot
atin
g th
e tw
osp
ectr
omet
er a
rms
and
chan
ging
m
agne
tic fi
elds
.
Ang
les
cove
red
in 2
001:
90
o , 60o , 4
5o , 40o , 3
5o , 20o , 1
2o , 8o , 4
o , 3o
Dat
a an
alys
is in
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
head
ing
tow
ards
Cen
tral
ity d
epen
denc
e of
ch
arge
d pa
rtic
le p
rodu
ctio
n at
m
idra
pidi
ty
Ana
lysi
s m
ainl
y by
E. J
. Kim
and
J. H
. Lee
Par
ticle
iden
tific
atio
n in
B
RA
HM
SB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
Mid
rapi
dity
per
form
ance
:
� Tim
e-of
-flig
ht r
esol
utio
n of
~75
pse
c
� π/K
sep
arat
ion
up to
~2.
5 G
eV/c
� K/p
sep
arat
ion
up to
~4.
0 G
eV/c
For
war
d sp
ectr
omet
er (
exam
ple)
:
� RIC
H g
ives
PID
up
to 2
5 G
eV/c
TO
FW
RIC
H
Sel
ect d
ata
from
y-p t p
lots
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
90o
60o
40o
Sel
ect d
ata
from
y-p t p
lots
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
90o
60o
40o
Sel
ect d
ata
from
y-p t p
lots
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
90o
60o
40o
Sel
ect d
ata
from
y-p t p
lots
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
90o
60o
40o
A w
ord
on e
xtra
ctin
g a
yiel
d fr
om a
p t spe
ctru
mB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
We
need
to e
xtra
pola
te to
inte
grat
e th
e sp
ectr
a, a
nd h
ere
we
have
tom
ake
an a
ssum
ptio
n ab
out t
he s
pect
ral s
hape
:
� Bol
tzm
an?
� pt e
xpon
entia
l?
� mt e
xpon
entia
l?
The
re is
a 2
0% d
iffer
ence
in th
eyi
elds
ext
ract
ed v
ia th
e di
ffere
ntfit
s -
this
goe
s in
to o
ur s
yste
mat
icun
cert
aint
y.
In th
e fo
llow
ing
we
have
use
dm
t exp
onen
tial f
its u
nles
s
othe
rwis
e no
ted.
Cen
tral
ity d
epen
denc
e of
ch
arge
d pa
rtic
le p
rodu
ctio
n at
m
idra
pidi
tyB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
Ana
lysi
s of
tota
l y~
0 da
ta s
et fr
om R
un-2
(A
u-A
u
)s N
N
� 200G
eV
App
rox.
30M
eve
nts
Cen
tral
ity d
epen
denc
e of
ch
arge
d pa
rtic
le p
rodu
ctio
n at
m
idra
pidi
tyB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
Ana
lysi
s of
tota
l y~
0 da
ta s
et fr
om R
un-2
(A
u-A
u
)
�
Eve
nts
divi
ded
into
cen
tral
ity c
lass
es (
0-10
,10-
20,2
0-40
,40-
60 %
) a
s de
term
ined
by
Mul
tiplic
ity d
etec
tor
(-2.
2<η<
2.2)
.s NN
� 200G
eV
Cen
tral
ity d
epen
denc
e of
ch
arge
d pa
rtic
le p
rodu
ctio
n at
m
idra
pidi
tyB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
Ana
lysi
s of
tota
l y~
0 da
ta s
et fr
om R
un-2
(A
u-A
u
)
�
Div
ided
into
cen
tral
ity c
lass
es (
0-10
,10-
20,2
0-40
,40-
60 %
) a
s de
term
ined
by
Mul
tiplic
ity d
etec
tor
(-2.
2<η<
2.2)
.
�
PID
by
Tim
e-O
f-F
light
, 3σ
cut w
ith r
espe
ct to
our
mom
entu
man
d to
f res
olut
ions
s NN
� 200G
eV
Mom
entu
m
Cor
rect
ions
app
lied
to th
e da
taB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
We
need
to a
pply
a n
umbe
r of
cor
rect
ions
to o
ur r
aw n
umbe
r of
part
icle
s to
get
the
corr
ect y
ield
. We'
ve c
orre
cted
for:
� trac
king
effi
cien
cy, u
sing
a tr
ack
embe
ddin
g te
chni
que
� effi
cien
cy in
mat
chin
g sp
ectr
omet
er tr
acks
to h
its in
the
time-
of-f
light
sys
tem
s
� geo
met
rical
acc
epta
nce,
usi
ng G
EA
NT
3.21
� phy
sics
effe
cts
like
mul
tiple
sca
tterin
g, p
roto
n kn
ocko
ut fr
om th
ebe
ampi
pe e
tc.,
also
eva
luat
ed w
ith G
EA
NT
3.21
Cav
eats
:T
he n
umbe
rs I
will
sho
w h
ave
not b
een
corr
ecte
d fo
r Λ
feed
-dow
n,an
d I w
ill o
nly
show
sta
tistic
al e
rror
s.
Cor
rect
ions
app
lied
to th
e da
taB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
We
need
to a
pply
a n
umbe
r of
cor
rect
ions
to o
ur r
aw n
umbe
r of
part
icle
s to
get
the
corr
ect y
ield
. We'
ve c
orre
cted
for:
� trac
king
effi
cien
cy, u
sing
a tr
ack
embe
ddin
g te
chni
que
� effi
cien
cy in
mat
chin
g sp
ectr
omet
er tr
acks
to h
its in
the
time-
of-f
light
sys
tem
s
� geo
met
rical
acc
epta
nce,
usi
ng G
EA
NT
3.21
� phy
sics
effe
cts
like
mul
tiple
sca
tterin
g, p
roto
n kn
ocko
ut fr
om th
ebe
ampi
pe e
tc.,
also
eva
luat
ed w
ith G
EA
NT
3.21
Cav
eats
:T
he n
umbe
rs I
will
sho
w h
ave
not b
een
corr
ecte
d fo
r Λ
feed
-dow
n,an
d I w
ill o
nly
show
sta
tistic
al e
rror
s.
Now
for
the
data
...
Cen
tral
ity d
epen
denc
e of
ch
arge
d ha
dron
spe
ctra
at y
=0
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
� The
cha
rged
had
ron
spec
tra
have
been
fitte
d to
a p
ower
law
form
ula:
in th
e ra
nge
0.2
< p t <
4.0
GeV
/c
� dN
/dη
and
<p t>
val
ues
are
calc
.
from
the
fit p
aram
eter
s, w
ith
f�
C
1
�pt
p 0
n
p t
2p 0
n
3
dN/d
η at
η=
0 fr
om
char
ged
hadr
ons
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
dN/d
η pe
r pa
rtic
ipan
t pai
r in
crea
ses
from
3.0
for
perip
hera
l col
lisio
ns to
3.5
for
cent
ral.
Thi
s is
con
sist
ent w
ith w
hat w
e sh
owed
inP
hys.
Rev
.Let
t.88:
2023
01,2
002
<pt
> r
ises
from
~0.
55 G
eV/c
for
perip
hera
l col
lisio
ns to
~0.
60 G
eV/c
for
cent
ral.
Cha
rged
had
ron
yiel
d pe
r N
coll,
com
paris
on b
etw
een
cent
ral a
nd p
erip
hera
lB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
The
rat
io b
etw
een
the
yiel
d of
char
ged
hadr
ons
from
cen
tral
an
d pe
riphe
ral c
ollis
ions
� incr
ease
s up
to p t ~
2.3
� dro
ps a
s p t in
crea
ses
beyo
nd
thi
s va
lue
Par
ticle
spe
ctra
from
ce
ntra
l AuA
u co
llisi
ons
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
Rec
ap o
f
Cen
t:0-
10%
Ana
lysi
s by
D. O
uerd
ane
Cha
rged
had
ron
spec
tra:
π+, π
-B
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
Cha
rged
had
ron
spec
tra:
K+, K
-B
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
0-10
%
Cha
rged
had
ron
spec
tra:
p, p
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
0-10
%
Com
paris
on: 0
-10%
vs.
40-
60% B
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
We
see
no s
igni
fican
t diff
eren
ce b
etw
een
the
beha
vior
s of
pt s
pect
ra
for
cent
ral a
nd p
erip
hera
l eve
nts.
Inve
rse
slop
e vs
. mas
s an
d ce
ntra
lity
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
� We
see
tran
sver
se fl
ow a
t all
rapi
ditie
s, a
nd a
ll ce
ntra
litie
s at
y=
0
� Inve
rse
slop
e de
crea
ses
with
incr
easi
ng r
apid
ity
� Inve
rse
slop
e de
crea
ses
som
ewha
t for
less
cen
tral
eve
nts
y=0,
0.9
y~3
<p t>
for π
, K, p
at y
=0
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
The
mea
n p t i
s ev
alua
ted
from
the
expo
nent
ial m
t fits
.
�
<p t>
for
all p
artic
le s
peci
es
incr
ease
s fr
om p
erip
hera
l to
cent
ral e
vent
s
�
Val
ues
and
cent
ralit
y de
pend
ence
is
goo
d ag
reem
ent w
ith
prel
imin
ary
Phe
nix
data
, exc
ept f
orth
e pi
ons.
Our
s ar
e hi
gher
, lik
ely
beca
use
of th
e m t fi
t.
dN/d
y pe
r pa
rtic
ipan
t pai
r at
y=
0 Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3s N
N
20
0Ge
V
� The
yie
ld p
er p
artic
ipan
t pai
r in
crea
ses
with
par
ticip
ant n
umbe
r fo
r al
l par
ticle
spe
cies
� K a
nd p
yie
lds
rise
fast
er th
an
π
Sta
tistic
al e
rror
s on
ly. D
omin
ant s
ourc
es o
fsy
stem
atic
err
ors
are
Npa
rt num
bers
and
extr
actio
n of
yie
lds.
K/π
rat
io a
t y=
0, 3
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
Rec
ap o
f
� Pos
itive
and
neg
ativ
e ra
tios
are
iden
tical
at
y=0.
� At y
=3
K- /π
- dro
ps
belo
w th
e po
sitiv
es
Ana
lysi
s by
D. O
uerd
ane
Cen
tral
ity d
epen
dent
π- /π+ r
atio
s at
y=
0B
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
The
π- /π
+ rat
io is
flat
ove
r th
e ra
nge
0.5<
pt<
3.5G
eV/c
.
�
R(c
entr
al)
is e
qual
with
in e
rror
s to
R(p
erip
hera
l)
Cen
tral
ity d
epen
dent
K- /K
+ r
atio
s at
y=
0B
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
The
K- /K
+ rat
ios
are
alm
ost f
lat o
ver
the
rang
e 0.
5<pt
<3.
5GeV
/c. T
here
may
be
a di
p at
low
p t
�
R(c
entr
al)
is a
gain
equ
al w
ithin
err
ors
to R
(per
iphe
ral)
Cen
tral
ity d
epen
dent
p / p
rat
ios
at y
=0
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
The
p /
p ra
tios
for
cent
ral e
vent
s ar
e fla
t ove
r th
e ra
nge
0.5
<pt
<3.
5GeV
/c.
�
R(c
entr
al)
is e
qual
with
in e
rror
s to
R(p
erip
hera
l)
K /
π ra
tios
at y
=0
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
K- /π
- , K+ /π
+ rat
ios
show
an
incr
ease
with
p t
�
The
re is
no
sign
ifica
nt d
iffer
ence
bet
wee
n ce
ntra
l and
perip
hera
l eve
nts.
p / π
rat
ios
at y
=0
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
p/π- , p
/π+ r
atio
s sh
ow a
n in
crea
se w
ith c
entr
ality
.
�
The
rat
ios
in c
entr
al e
vent
s re
ach
0.7~
0.8
at 2
GeV
/c,
whi
le in
per
iphe
ral e
vent
s th
e ra
tios
go u
p to
0.4
~0.
5.
The
BR
AH
MS
exp
erim
ent
Add
ition
s si
nce
2001
B
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
C4
- C
here
nkov
cou
nter
Spe
ctro
met
er tr
igge
rs fo
r pp
and
dA
� Ext
ende
d pt
cov
erag
e at
mid
rap.
� Bet
ter
timin
g re
solu
tion
� Allo
ws
trig
gerin
g on
eve
nts
w. t
rack
s in
spe
ctro
met
er fo
r in
c. d
ata
rate
TO
FW
II se
cond
tim
e-of
-flig
htw
all
Wha
t to
expe
ct fr
om B
RA
HM
Sin
the
near
futu
reB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
Exi
stin
g A
uAu
data
:
� Ana
lysi
s is
ong
oing
aw
ay fr
om m
idra
pidi
ty
� Our
cen
tral
ity d
epen
dent
spe
ctra
will
be
exte
nded
out
to y
~3
pp a
nd d
Au
data
:
� pp
data
are
bei
ng a
naly
zed
to s
erve
as
base
line
for
our
AuA
u da
ta
� dA
u da
ta a
re b
eing
take
n an
d an
alyz
ed a
s w
e ge
t the
m. N
ow w
e on
ly
nee
d th
e m
achi
ne to
del
iver
eno
ugh
beam
for
a go
od h
igh
pt s
ampl
e!
A fu
ture
AuA
u ru
n at
full
RH
IC e
nerg
y:
� C4
and
TO
FW
II ex
tend
our
cap
abili
ties
at m
idra
pidi
ty, a
llow
ing
for
an
even
bet
ter
com
paris
on b
etw
een
mid
and
hig
h ra
pidi
ties
� Our
pt c
over
age
at m
idra
pidi
ty w
ill g
o in
crea
se, n
icel
y co
mpl
emen
ting
the
dat
a w
e al
read
y ha
ve
Con
clus
ions
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
BR
AH
MS
has
mea
sure
d th
e tr
ansv
erse
dyn
amic
s of
cha
rged
had
rons
at m
idra
pidi
ty fr
om A
uAu
colli
sion
s at
In b
rief,
we
have
sho
wn
that
� for
char
ged
hadr
ons,
<p
t> in
crea
ses
as a
func
tion
of c
entr
ality
� this
als
o ap
plie
s to
eac
h pa
rtic
le s
peci
es in
divi
dual
ly
� the
glob
al b
ehav
ior
of id
entif
ied
part
icle
spe
ctra
doe
s no
t cha
nge
with
cen
tral
ity
� like
-par
ticle
rat
ios
are
cons
tant
as
a fu
nctio
n of
pt a
nd c
entr
ality
� the
p/π r
atio
sho
ws
an in
crea
se fo
r m
ore
cent
ral e
vent
s
s NN
� 200G
eV
Con
clus
ions
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
BR
AH
MS
has
mea
sure
d th
e tr
ansv
erse
dyn
amic
s of
cha
rged
had
rons
at m
idra
pidi
ty fr
om A
uAu
colli
sion
s at
In b
rief,
we
have
sho
wn
that
� for
char
ged
hadr
ons,
<pt
> in
crea
ses
as a
func
tion
of c
entr
ality
� this
als
o ap
plie
s to
eac
h pa
rtic
le s
peci
es in
divi
dual
ly
� the
glob
al b
ehav
ior
of id
entif
ied
part
icle
spe
ctra
doe
s no
t cha
nge
with
cen
tral
ity
� like
-par
ticle
rat
ios
are
cons
tant
as
a fu
nctio
n of
pt a
nd c
entr
ality
� the
p/π r
atio
sho
ws
an in
crea
se fo
r m
ore
cent
ral e
vent
s
s NN
� 200G
eV
Tha
nk y
ou fo
r lis
teni
ng
Com
paris
on: 0
-10%
vs.
40-
60%
mt-m
0B
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
Hig
h pt
, nuc
lear
m
odifi
catio
n fa
ctor
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
Rec
ap o
f
RA
A
�d²N
A
� A
� dp t
d
�
d²
�N� N
� dp t
d
�
�N
� N
Nb
in
≈ 15
0≈4
0-60
%
551
10-2
0%
764
5-10
%
965
0-5%
⟨Nbi
nary
⟩ce
nt.
The
lin
es s
how
ratio
s of
fits
.
Ana
lysi
s by
C. E
. Jor
gens
en
Num
bers
from
nucl
-ex/
0206
011
Cal
cula
ting
<p t>
from
mt s
pect
raB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
We'
ve fi
t our
spe
ctra
with
an
m t exp
onen
tial t
o ex
trac
t the
inve
rse
slop
e.
Usi
ng th
e fit
func
tions
for
p t:d
N dp t
� p t·
e
�
p t2
� m2
T
p t·d
N dp t
� p t²·
e�
p t2� m
2
T
p t�
�p t
²·d
N p t
�
p t·d
N p t
we
can
extr
act t
he m
ean
pt b
y in
tegr
atin
g:
Ana
lysi
s de
tails
1:
Tra
ck a
nd e
vent
sel
ectio
nB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
All
MR
S 9
0 de
gree
dat
a se
t
->
run
4692
- r
un59
83
-
> B
B, T
PC
, TO
FW
, BbV
erte
x ca
libra
tion
�
No
spec
ific
Trig
ger
sele
ctio
n
�
Cen
tral
ity c
ut fr
om la
test
cal
ibra
tion
from
DB
�
Sel
ect
Goo
d M
rsT
rack
s
�
Mag
net F
iduc
ial c
ut :
1cm
(x,
y) fr
om e
dge
�
Run
-by-
Run
fitti
ng
- D
iff(V
zdc-
Vbb
) : 4
σ cu
t
- m
atch
ing
(Dan
g,D
y,D
aly,
Ty)
: 3σ
cut
Ana
lysi
s de
tails
2:
Acc
epta
nce
map
sB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
Fla
t dis
trib
utio
ns :
p,
θ
->
10M
at e
ach
setti
ng
->
-17
.5cm
< z
<17
.5cm
, ∆z =
5cm
�
New
TP
M2
geom
etry
for
2001
dat
a se
tting
�
Sel
ectio
n : s
ame
as u
sed
in d
ata
->
rem
ove
bad
TO
FW
sla
ts
->
Mag
net F
iduc
ial c
ut :
1cm
(x,
y)
�
y-m
t, y-
pt m
ap fo
r π,
K, p
->
Acc
epta
nce
valu
es b
elow
4.5
(5.5
) ar
e
a
pplie
d to
dat
a. (
redu
ce e
dge
effe
ct)
Ana
lysi
s de
tails
3:
Cor
rect
ions
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
Tra
ck-b
y-T
rack
cor
rect
ions
�
TP
C e
ffici
ency
: ~
89%
, 96%
-
> a
s a
func
tion
of #
of c
lust
ers
�
TO
FW
: re
mov
e ba
d sl
ats
�
Cor
rect
ions
for
part
icle
spe
cies
-
> M
ultip
le s
catte
ring
: π, Κ
, p
->
Dec
ay c
orre
ctio
n : π
, K
->
Abs
orpt
ion
: pba
r
->
as
a fu
nctio
n of
mom
entu
m
Bjø
rn H
. Sam
set
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
@
Cen
t:0-
10%
Cen
tral
ity d
epen
denc
e of
ch
arge
d pa
rtic
le p
rodu
ctio
n at
m
idra
pidi
tyB
jørn
H. S
amse
t
Tra
nsve
rse
dyna
mic
sat
RH
IC, M
arch
200
3
�
Ana
lysi
s of
tota
l y~
0 da
ta s
et fr
om R
un-2
(A
u-A
u
)
�
Div
ided
into
cen
tral
ity c
lass
es (
0-10
,10-
20,2
0-40
,40-
60 %
) a
s de
term
ined
by
Mul
tiplic
ity d
etec
tor
(-2.
2<η<
2.2)
.
�
PID
by
Tim
e-O
f-F
light
, 3σ
cut w
ith r
espe
ct to
our
mom
entu
man
d to
f res
olut
ions
s NN
� 200G
eV
1) Y
ield
s an
d <
p t> fr
om c
harg
ed h
adro
ns
2) Y
ield
s an
d <
p t> fr
om id
entif
ied
hadr
ons
3) C
entr
ality
and
p t dep
ende
nce
of li
ke a
nd u
nlik
e pa
rtic
le r
atio
s
...an
d no
w fo
r th
e da
ta:
