cohen vanderbilt physicstalk - swarthmore college
TRANSCRIPT
Hig
h En
ergy
Den
sity
Pla
sma
Phys
ics
Expe
rimen
ts a
t the
Nat
iona
l Lab
s: X
-ray
Sp
ectro
scop
y, In
ertia
l Con
finem
ent F
usio
n,
and
Labo
rato
ry A
stro
phys
ics
Dav
id C
ohen
Swar
thm
ore
Col
lege
D
ept.
of P
hysi
cs a
nd A
stro
nom
y
astro
.swar
thm
ore.
edu/
~coh
en→
pres
enta
tions
→va
nder
bilt
Talk
Out
line
1.Fa
cilit
ies a
nd c
apab
ilitie
s
2.In
ertia
l Con
finem
ent F
usio
n (I
CF)
3.O
MEG
A e
xper
imen
ts: X
-ray
spec
tral d
iagn
ostic
s of I
CF
mat
eria
ls
4.La
bora
tory
ast
roph
ysic
s
5.C
reat
ing
an X
-ray
pho
toio
nize
dne
bula
in th
e la
bora
tory
Hig
h En
ergy
Den
sity
Pla
sma
Phys
ics a
t N
atio
nal F
acili
ties
Las
ers
NO
VA
(Liv
erm
ore)
-cl
osed
in la
te 1
990s
-10
bea
ms,
20
kJ U
V li
ght i
n ~1
ns
OM
EGA
(U. R
oche
ster
/LLE
) -op
ened
in 1
970s
-60
be
ams,
30 k
J, U
V (N
d gl
ass l
aser
)
Nat
iona
l Ign
ition
Fac
ility
(NIF
) (Li
verm
ore)
-co
min
g on
lin
e th
is d
ecad
e -1
92 b
eam
s, 2
MJ
Z-p
inch
es
Z-m
achi
ne/P
BFA
-II (
Sand
ia) -
orig
inal
ly b
uilt
in 1
970s
-20
MA
of c
urre
nt in
a c
ylin
dric
al w
ire a
rray
-~2
MJ o
f X-
rays
in ~
10 n
s
The
se fa
cilit
ies a
re o
pen
to n
on-la
b sc
ient
ists
DO
E’s N
atio
nal L
aser
Use
rs F
acili
ties (
NLU
F)
prog
ram
ena
bles
uni
vers
ity sc
ient
ists
acc
ess o
f O
MEG
A (a
nd p
revi
ousl
y N
OV
A),
as w
ell a
s oth
er
faci
litie
s at L
os A
lam
os, e
tc. -
som
e co
ordi
natio
n w
ith
lab
scie
ntis
ts a
nd te
chni
cian
s is r
equi
red/
prov
ided
Use
of t
he Z
-Mac
hine
gen
eral
ly re
quire
s a S
andi
a co
llabo
rato
r, bu
t DO
E’s f
usio
n gr
ants
pro
gram
(SB
SS)
prov
ides
supp
ort a
nd c
an fa
cilit
ate
colla
bora
tions
Typ
es o
f exp
erim
ents
: gen
eral
ly in
volv
ing
high
ene
rgy
dens
ity p
lasm
as (>
105
atm
)
Can
ach
ieve
mul
ti-G
Pa p
ress
ures
, 103
g cm
-3de
nsiti
es,
mul
ti-m
illio
n K
tem
pera
ture
s in
10 c
m3
volu
me
Soph
istic
ated
dia
gnos
tics a
re a
vaila
ble
at th
ese
faci
litie
s (ti
me
reso
lved
imag
ing
and
spec
trosc
opy,
neu
tron
and
othe
r par
ticle
det
ecto
rs, f
ast r
adio
grap
hy, e
tc.)
-Pl
asm
a in
stab
ility
stud
ies (
inst
abili
ty g
row
th ra
te,
incl
udin
g ap
plic
atio
ns to
supe
rnov
a ex
plos
ions
)
-EO
S st
udie
s (e.
g. o
f hyd
roge
n un
der v
ery
high
pr
essu
re, a
pplic
atio
ns to
gia
nt p
lane
t int
erio
rs)
-Rad
iatio
n an
d th
erm
al e
nerg
y tra
nspo
rt
-Ato
mic
phy
sics
and
opa
citie
s
-Sho
ck p
hysi
cs
Lase
r Fac
ilitie
sG
ener
ally
Nd
glas
s las
ers (
but 5
kJ g
as (K
rF) l
aser
at N
RL)
; 1.0
6 µm
IR li
ght,
freq
uenc
y tri
pled
into
the
near
UV
; mul
ti-be
am (f
or
sym
met
ry a
nd fl
exib
ility
)
Live
rmor
e’s N
IF w
ill b
e co
mpl
eted
in se
vera
l yea
rs,
and
is a
lread
y op
erat
iona
l.
Her
e ar
e so
me
view
s of t
he
huge
targ
et c
ham
ber,
durin
g its
con
stru
ctio
n.
Lase
rs c
an b
e us
ed d
irect
ly to
acc
eler
ate
e.g.
foils
, driv
e sh
ock
wav
es, a
nd c
ompr
ess m
ater
ial s
ampl
es
Als
o, th
ey c
an b
e us
ed in
dire
ctly
to g
ener
ate
X-r
ays -
lase
r lig
ht is
ther
mal
ized
by a
hig
h-Z
foil
or in
side
a h
igh-
Z en
clos
ure,
or h
ohlr
aum
Z-Pi
nche
sA
cur
rent
pas
sing
thro
ugh
a va
poriz
ed w
ire o
r oth
er c
ylin
dric
al
plas
ma
gene
rate
s a p
oloi
dalm
agne
tic fi
eld
that
inte
ract
s with
the
curr
ent,
gene
ratin
g a
Lore
ntz
forc
e in
the
dire
ctio
n of
the
curr
ent
axis
-th
e re
sult
is a
self-
pinc
hed
plas
ma
(e.g
. lig
htni
ng) -
and
the
on-a
xis c
ompr
essi
on c
an g
ener
ate
a sh
ock
wav
e, th
at e
ffic
ient
ly
conv
erts
the
mag
netic
ene
rgy
to h
eat,
and
then
X-r
ays.
E x
B fo
rce
wire
s
B-f
ield
Z-ax
is; n
et
curr
ent;
foam
The
Z-M
achi
ne a
t San
dia
-app
licat
ion
of a
pul
sed-
pow
er g
ener
ator
(Par
ticle
Bea
m F
usio
n A
ccel
erat
or
(PB
FA))
-w
orld
’s la
rges
Z-p
inch
and
mos
t pow
erfu
l X-
ray
sour
ce (2
MJ i
n 10
ns →
200
TW o
f X-r
ay p
ower
)
Expe
rimen
tal p
acka
ges c
an b
e fie
lded
nea
r or e
ven
with
in
the
pinc
h -h
ohlra
umsa
djac
ent t
o th
e pi
nch;
cap
sule
s and
ot
her m
ater
ial s
ampl
es e
mbe
dded
in th
e fo
am c
ore
Talk
Out
line
1.Fa
cilit
ies a
nd c
apab
ilitie
s
2.In
ertia
l Con
finem
ent F
usio
n (I
CF)
3.O
MEG
A e
xper
imen
ts: X
-ray
spec
tral d
iagn
ostic
s of I
CF
mat
eria
ls
4.La
bora
tory
ast
roph
ysic
s
5.C
reat
ing
an X
-ray
pho
toio
nize
dne
bula
in th
e la
bora
tory
Iner
tial C
onfin
emen
t Fus
ion
(IC
F)
→th
e fin
al p
rodu
cts o
f a fu
sion
reac
tion
wei
gh 0
.7%
less
than
th
e in
itial
ingr
edie
nts,
thus
0.7
% m
c2is
con
verte
d in
to e
nerg
y:
One
gra
m o
f fue
l yie
lds 1
75,0
00 k
W-h
ours
of e
nerg
y
Deu
teriu
m-T
ritiu
m fu
sion
reac
tions
ha
ve th
e bi
gges
t cro
ss se
ctio
n
Ener
gy is
rele
ased
prim
arily
in th
e fo
rm o
f fas
t neu
trons
; the
re a
re v
ario
us
sche
mes
for h
arne
ssin
g th
is e
nerg
y
A w
orki
ng te
st-r
eact
or is
dec
ades
off
st
ill, b
ut fu
sion
pow
er is
an
attra
ctiv
e lo
ng-te
rm so
lutio
n to
our
ene
rgy
need
s
Diff
eren
t Fus
ion
Met
hods
Prac
tical
pro
blem
:com
bina
tion
of h
igh
tem
pera
ture
s and
den
sitie
s ar
e re
quire
d to
forc
e po
sitiv
ely
char
ged
nucl
ei to
geth
er, b
ut th
e re
sulti
ng h
igh
pres
sure
will
tend
to b
low
fusi
on p
lasm
a (h
ot io
nize
d ga
s) a
part
3 pr
imar
y pl
asm
a co
nfin
emen
t m
etho
dsI.
Gra
vita
tiona
l con
finem
ent:
astro
phys
ical
con
text
s
II. M
agne
tic c
onfin
emen
t: to
kom
aks
III.
Iner
tial c
onfin
emen
t-in
ertia
of
the
fuel
con
fines
it fo
r the
na
nose
cond
s (10
-9s)
requ
ired
for
the
fusi
on re
actio
n to
pro
ceed
How
Doe
s Ine
rtial
Con
finem
ent F
usio
n (I
CF)
Wor
k?
A sp
heric
al c
apsu
le fi
lled
with
hyd
roge
n fu
el is
bom
bard
ed w
ith
ener
gy, c
ompr
essi
ngan
d he
atin
ga
smal
l reg
ion
in th
e ce
nter
of t
he
fuel
.
The
fusi
on re
actio
ns fr
om th
is c
entra
l “ho
t spo
t” d
epos
it en
ough
ener
gy in
the
rest
of t
he fu
el th
at fu
sion
occ
urs t
here
too–
this
pr
oces
s is r
efer
red
to a
s ign
ition
.
Not
e th
at d
urin
g th
e ve
ry sh
ort p
erio
d of
igni
tion
(a fe
w n
anos
econ
ds, o
r a b
illio
nth
of a
seco
nd) t
he fu
el is
pus
hed
inw
ard,
soits
ow
n in
ertia
act
s to
impe
de it
s dis
asse
mbl
y; h
ence
the
term
iner
tial c
onfin
emen
t fus
ion.
Phys
ical
Req
uire
men
ts fo
r fus
ion
–ov
erco
min
g th
e C
oulo
mb
Bar
rier
Not
e: c
ente
r of t
he S
un h
as T
~15
X 1
06K
, ρ ~
100
g cm
-3
In a
n ab
latio
n-dr
iven
cap
sule
impl
osio
n w
ith a
shoc
k ve
loci
ty o
f 300
km
s-1, a
hot
spot
with
an
area
lm
ass o
f >0.
1 g
cm-2
and
a te
mpe
ratu
re o
f sev
eral
keV
can
igni
te (a
lpha
par
ticle
ene
rgy
depo
sitio
n ex
ceed
s los
ses)
. Ta
ken
from
Lin
dl, P
hysi
cs o
f Pla
smas
, 2, 3
933,
199
5.
Indi
rect
-Driv
e IC
F
Indi
rect
-driv
e IC
F de
liver
s the
ene
rgy
of a
lase
r (or
ion
beam
) no
t dire
ctly
to th
e fu
el c
apsu
le, b
ut ra
ther
to a
n en
clos
ure,
or
hohl
raum
, in
whi
ch it
is th
erm
aliz
ed.
This
ther
mal
radi
atio
n is
typi
cally
cha
ract
eriz
ed b
y te
mpe
ratu
res o
f 2 to
3 m
illio
n K
, so
it is
prim
arily
X-r
ays.
Imag
es o
f a g
old
hohl
raum
used
at
the
NO
VA
lase
r at L
iver
mor
e (f
ar le
ft).
The
pict
ure
on th
e rig
ht w
as ta
ken
in X
-ray
s and
sh
ows t
he la
ser h
otsp
ots o
n th
e in
teri
orof
the
hohl
raum
radi
atin
g th
roug
h th
e ho
hlra
umw
alls
.
Indi
rect
-driv
e IC
F C
apsu
le Im
plos
ion:
co
mpr
essi
on a
nd h
eatin
g vi
a ab
latio
n
The
X-r
ays t
hat f
ill th
e ho
hlra
umba
the
the
fuel
cap
sule
at i
ts c
ente
r, de
posi
ting
ener
gy
on th
e ou
tsid
e of
the
capu
lean
d he
atin
g th
e ou
ter c
apsu
le la
yers
(ref
erre
d to
as t
he
abla
tor)
. Th
is h
ot p
lasm
a ru
shes
aw
ay fr
om th
e ca
psul
e in
to th
e re
lativ
e va
cuum
of
the
hohl
raum
. C
onse
rvat
ion
of m
omen
tum
cau
ses c
ompr
essi
on o
f the
inte
rior o
f the
ca
psul
e (th
e ro
cket
effe
ct),
with
an
inw
ard
mov
ing
shoc
kwav
e co
nver
ging
on
the
fuel
in
the
caps
ule’
s cen
ter.
shoc
k w
ave
radi
atio
n w
ave
A h
ydro
dyna
mic
alsi
mul
atio
n of
the
abla
tion
and
com
pres
sion
of a
solid
pl
astic
sam
ple
by th
erm
al X
-ray
s. Th
e X
-ray
s are
inci
dent
from
the
left.
H
ot, t
enuo
us m
ater
ial e
xpan
ds
rapi
dly
off t
he (p
revi
ousl
y) so
lid
surf
ace
tow
ard
the
left,
whi
le a
sh
ockw
ave
mov
ing
tow
ard
the
right
co
mpr
esse
s the
rem
aini
ng m
ater
ial.
Cle
arly
, con
trolli
ng th
e in
tera
ctio
n of
the
X-r
ays w
ith th
e ou
ter
abla
tor l
ayer
of t
he fu
el c
apsu
le is
cru
cial
for g
ener
atin
g an
ef
ficie
nt im
plos
ion
and
subs
eque
nt ig
nitio
n of
the
fusi
on fu
el.
Typi
cally
, fue
l cap
sule
s con
sist
of
a sp
heric
al p
last
ic sh
ell (
the
abla
tor)
surr
ound
ing
high
de
nsity
hyd
roge
n ic
e (s
ee th
e sc
hem
atic
on
the
left)
.
Abla
tor d
opan
tsaf
fect
the
opac
ity a
nd d
ensi
ty, c
hang
ing
the
man
ner
in w
hich
ene
rgy
is a
bsor
bed
by th
e ab
lato
r.B
y ad
ding
mid
-Z d
opan
ts(li
ke b
rom
ine,
cop
per,
or g
erm
aniu
m) t
o th
e pl
astic
or
bery
llium
cap
sule
abl
ator
, we
can
cont
rol t
he d
ensi
ty a
nd o
paci
ty o
f the
abl
ator
. Th
is in
turn
con
trols
the
abla
tion/
com
pres
sion
phy
sics
in th
e fu
el c
apsu
le. T
he
dopa
ntsa
lso
prov
ide
a ‘s
hiel
d’ a
gain
st ra
diat
ion
preh
eat o
f the
fuel
, allo
win
g fo
r ef
ficie
nt c
ompr
essi
on a
t the
low
est e
ntro
py p
ossi
ble.
Ros
sela
nd M
ean
Gro
up O
paci
ty
1.E
-01
1.E
+00
1.E
+01
1.E
+02
1.E
+03
1.E
+04
1.E
+05 10
100
1000
1000
0
Ene
rgy
(eV
)
Absorption Coefficiant (cm^2/g)
Und
oped
Dop
ed
n_io
n =
5e20
/cc
kT_e
= 1
50eV
Talk
Out
line
1.Fa
cilit
ies a
nd c
apab
ilitie
s
2.In
ertia
l Con
finem
ent F
usio
n (I
CF)
3.O
ME
GA
exp
erim
ents
: X-r
ay sp
ectr
al d
iagn
ostic
s of
ICF
mat
eria
ls
4.La
bora
tory
ast
roph
ysic
s
5.C
reat
ing
an X
-ray
pho
toio
nize
dne
bula
in th
e la
bora
tory
OM
EGA
exp
erim
ents
: X-r
ay sp
ectra
l dia
gnos
tics o
f IC
F m
ater
ials
Goa
l: To
stud
y th
e ef
fect
s of a
blat
or d
opan
tson
the
radi
atio
n-hy
drod
ynam
ics o
f the
abl
atio
n an
d ca
psul
e im
plos
ion;
and
To d
evel
op a
tech
niqu
e fo
r dia
gnos
ing
the
inst
anta
neou
s pr
oper
ties a
t a lo
catio
n in
the
inte
rior
of a
solid
sam
ple.
Spec
ifica
lly, w
e w
ant t
o m
easu
re th
e tim
e at
whi
ch th
e ra
diat
ion
wav
e re
ache
s a sp
ecifi
c de
pth
in th
e ab
lato
r as a
fu
nctio
n of
dop
antl
evel
.
By
putti
ng a
pla
nar s
ampl
e of
pla
stic
abl
ator
mat
eria
l on
the
side
of a
hoh
lraum
we
can
sim
plify
the
geom
etry
Thes
e ex
perim
ents
wer
e ca
rrie
d ou
t in
Apr
il 20
00 a
t the
O
MEG
A la
ser.
On
the
right
is a
pho
togr
aph
of a
hoh
lraum
targ
et, o
n th
e le
ft is
a sc
hem
atic
.
Not
e: th
ese
hohl
raum
s, w
ith la
sers
ent
erin
g on
onl
y on
e si
de a
re re
ferr
ed to
as h
alfr
aum
s.
The
abla
tor “
pack
ages
” ar
e th
in, p
lana
r san
dwic
hes o
f act
ual a
blat
or
mat
eria
l sur
roun
ding
a v
ery
thin
laye
r of a
spec
trosc
opic
trac
er
halfr
aum
radi
atio
n
Ge-
dope
d or
und
oped
plas
tic
NaC
ltra
cer
< 0.
5 µ~20
µ~5
µTh
is p
acka
ge, m
ount
ed o
ver a
ho
le o
n th
e ou
tsid
e of
the
hohl
raum
, act
ually
sees
a
time-
depe
nden
t rad
iatio
n fie
ld
(the
“driv
e”) t
hat i
s ver
y si
mila
r to
wha
t’s se
en b
y a
sphe
ricca
psul
e in
the
cent
er
of a
hoh
lraum
.
Whe
n w
e se
e th
e sp
ectro
scop
ic si
gnat
ure
of th
e ch
lorin
e in
the
trace
r, w
e kn
ow th
e ra
diat
ion
wav
e ha
s re
ache
d it.
Expe
rimen
tal S
et-u
pIn
clud
ing
sche
mat
ics o
f dia
gnos
tic li
nes-
of-s
ight
Not
e: o
nly
one
(blu
e) b
eam
into
the
halfr
aum
is sh
own
here
,for s
impl
icity
. All
shot
s wer
e ca
rrie
d ou
t with
15
beam
s.
Dia
gnos
tics
The
DA
NTE
cam
era
mon
itors
th
e tim
e-de
pend
ent r
adia
tion
field
insi
de th
e ha
lfrau
m(lo
okin
g in
thro
ugh
the
lase
r en
tranc
e ho
le).
The
spec
trom
eter
look
s for
Kα
abso
rptio
nsi
gnal
s fro
m th
e ch
lorin
e tra
cer i
n th
e ab
lato
r pa
ckag
e.
TVS-
X v
iew
Expe
rimen
tal C
onfig
urat
ion
LEH
faci
ng P
-7 (L
XS
in P
-6)
Gol
d H
alfr
aum
s: L
=120
0µ, R
=800
µw
ashe
r/ape
rture
Bi/P
bba
cklig
herf
oil
Pb-d
oped
pla
stic
m
ount
posi
tioni
ng w
ires
stal
k
TVS-
Y v
iew
TVS-
X v
iew
of p
lain
foil
Witn
ess p
late
s wer
e m
ount
ed o
n th
e en
ds o
f hal
frau
ms;
ba
cklig
hter
foils
hun
g ~1
.5m
m fr
om L
EH
Mod
elin
g
1.V
iew
fact
or m
odel
ing
of h
ohlra
umdr
ive,
co
nstra
ined
by
DA
NTE
(and
usi
ng m
easu
red
beam
pro
files
as i
nput
)
2.H
ydro
dyna
mic
cal
cula
tions
for t
ime-
depe
nden
t w
itnes
s pla
te p
rope
rties
(1-D
Lag
rang
ian;
DC
A
and
UTA
ato
mic
and
EO
S m
odel
s; sh
ort
char
acte
ristic
s mul
ti-gr
oup
radi
atio
n tra
nspo
rt)
3.C
RE
post
-pro
cess
ing
for s
pect
ral s
ynth
esis
We
use
code
s writ
ten
by Jo
e M
acFa
rlane
at P
rism
Com
puta
tiona
l Sci
ence
s as w
ell a
s som
e pu
blic
ly a
vaila
ble
code
s writ
ten
at th
e U
. Wis
cons
in F
usio
n Te
chno
logy
Inst
itute
.
VisR
adV
iew
fact
or M
odel
ing
Not
e: n
ot a
ll be
ams a
re sh
own.
•15
cone
2 a
nd c
one
3 be
ams i
nto
the
halfr
aum
•1 n
s squ
are
puls
e
•3 b
eam
s ont
o th
e ba
cklig
hter
foil;
als
o 1
ns sq
uare
, but
stag
gere
d in
tim
e fo
r mor
e ev
en
back
light
er so
urce
.
Con
stra
inin
g th
e vi
ewfa
ctor
mod
elin
g
Rad
iatio
n flu
x m
onito
red
on e
lem
ent
at D
AN
TE p
ositi
on
•Bea
m p
ower
s and
po
intin
gsar
e kn
own
•Tem
pera
ture
dep
ende
nt
albe
dois
mod
eled
(s
epar
atel
y)
•X-r
ay c
onve
rsio
n ef
ficie
ncy
(of l
aser
s) is
a
free
par
amet
er
Shot
#26
Onc
e th
e ho
hlra
umra
diat
ion
field
is m
odel
ed: H
ydro
si
mul
atio
ns o
f the
abl
ator
sam
ple
Not
e: in
Ge-
dope
dsa
mpl
e, th
e pe
aks a
re n
arro
wer
--sh
ock
wav
e an
d ra
diat
ion
wav
e m
ove
slow
er
Ele
ctro
n T
empe
ratu
re
InitialDepth(cm)
kTe(eV)
0.00
10.
002
020406080100
120
140
160
180
200
meshpt.=101time=
0.40(nsec.)
meshpt.=101time=
0.80(nsec.)
meshpt.=101time=
1.20(nsec.)
meshpt.=101time=
1.60(nsec.)
meshpt.=101time=
2.00(nsec.)
BU
CKY
Sim
ulat
ion
Und
oped
,Tr(p
eak)
=175
eV
InitialDepth(cm)
kTe(eV)0.
001
0.00
2020406080100
120
140
160
180
200
meshpt.=101time=
0.40(nsec.)
meshpt.=101time=
0.80(nsec.)
meshpt.=101time=
1.20(nsec.)
meshpt.=101time=
1.60(nsec.)
meshpt.=101time=
2.00(nsec.)
BU
CKY
Sim
ulat
ion
Dop
ed,T
r(p
eak)
=175
eV
Sam
e si
mul
atio
ns: R
adia
tion
Tem
pera
ture
Slow
er ra
diat
ion
wav
e ve
loci
ty in
the
dope
d sa
mpl
e
InitialDepth(cm)
kTr(eV)
0.00
10.
002
020406080100
120
140
160
180
200
meshpt.=101time=
0.40(nsec.)
meshpt.=101time=
0.80(nsec.)
meshpt.=101time=
1.20(nsec.)
meshpt.=101time=
1.60(nsec.)
meshpt.=101time=
2.00(nsec.)
BU
CK
YSi
mul
atio
nU
ndop
ed,T
r(p
eak)
=175
eV
InitialDepth(cm)
kTr(eV)0.
001
0.00
2020406080100
120
140
160
180
200
meshpt.=101time=
0.40(nsec.)
meshpt.=101time=
0.80(nsec.)
meshpt.=101time=
1.20(nsec.)
meshpt.=101time=
1.60(nsec.)
meshpt.=101time=
2.00(nsec.)
BU
CK
YSi
mul
atio
nD
oped
,Tr(p
eak)
=175
eV
4.40
4.45
4.50
4.55
4.60
4.65
4.70
4.75
4.80
0123456
He
L
i
Be
B
C
N
O
F
Non
-Pla
ncki
an In
cide
nt F
lux
; M
odel
ηx
0.2
ns
0.4
ns
0.6
ns
0.8
ns
1.0
ns
Intensity (arb. units)W
avel
engt
h (A
)
Spec
tral s
ynth
esis
: pos
t-pro
cess
ing
of h
ydro
resu
lts
(und
oped
sam
ple)
Not
e: S
houl
dn’t
see
Be-
like
until
~0.
6 ns
.
Dat
a ar
e ac
quire
d w
ith a
fast
stre
ak c
amer
a an
d sp
ectro
grap
h
In th
ese
figur
es w
e’re
focu
sing
in o
n th
e tim
es w
hen
the
trace
r sig
nals
turn
on.
Th
ere’
s a d
elay
of b
etw
een
100
and
200
ps in
the
appe
aran
ce o
f Kα
abso
rptio
n si
gnal
s on
the
dope
d an
d un
dope
dsi
des.
Not
e th
at y
ou c
an a
lso
see
the
ioni
zatio
n ba
lanc
e m
ovin
g to
war
d hi
gher
stag
es (B
e →
Li →
He)
as t
ime
goes
on.
Und
oped
Dop
ed w
ith 1
.5 %
Ger
man
ium
Fina
lly -
the
data
"Tur
n-on
" tim
e vs
. T_r
(p
eak)
0.40
0.50
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
150.
017
0.0
190.
0T_
r (pe
ak) (
eV)
Time (ns)
4.5
µm
"Tur
n-on
" tim
e vs
. T_r
(p
eak)
0.40
0.50
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
150.
017
0.0
190.
0T_
r (pe
ak) (
eV)
Time (ns)
6.5
µm
"Tur
n-on
" tim
e vs
. T_r
(p
eak)
0.40
0.50
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
150.
017
0.0
190.
0T_
r (pe
ak) (
eV)
Time (ns)
8.5
µm
Cal
cula
ted
trac
er tu
rn-o
n tim
e vs
. dri
ve te
mpe
ratu
re
trace
r dep
thre
d=do
ped;
blu
e=un
dope
d
from
dat
a
Qui
ck L
ook
at M
ain
Res
ult
Shot
#26
: und
oped
Shot
#28
: dop
ed
Som
e ab
sorp
tion
sign
al, a
ppar
ently
, on
a no
isy
cont
inuu
m:
Turn
s on
late
r in
the
dope
d sa
mpl
e (a
nd tr
acer
was
eve
n sh
allo
wer
in
this
sam
ple)
; See
pro
gres
sion
thro
ugh
ioni
zatio
n st
ates
.
But--
in b
oth
case
s--e
arlie
r tur
n-on
than
mod
els p
redi
ct
CO
NC
LUSI
ON
S
Bac
klit-
abso
rptio
n sp
ectro
scop
y of
a sm
all s
ampl
e in
an
envi
ronm
ent c
onta
inin
g st
rong
radi
atio
n an
d ho
t pla
sma
is
diff
icul
t
In b
oth
type
s of t
arge
ts, t
he si
gnal
turn
-on
time
was
ear
lier (
by
fact
or ~
2) th
an e
xpec
ted,
and
low
er io
niza
tion
stag
es w
ere
not
seen
).
But
, sig
nal t
urne
d on
soon
er in
und
oped
sam
ple
than
in d
oped
sa
mpl
e.
Talk
Out
line
1.Fa
cilit
ies a
nd c
apab
ilitie
s
2.In
ertia
l Con
finem
ent F
usio
n (I
CF)
3.O
MEG
A e
xper
imen
ts: X
-ray
spec
tral d
iagn
ostic
s of I
CF
mat
eria
ls
4.L
abor
ator
y as
trop
hysi
cs
5.C
reat
ing
an X
-ray
pho
toio
nize
dne
bula
in th
e la
bora
tory
Labo
rato
ry A
stro
phys
ics
Ast
roph
ysic
s is t
radi
tiona
lly n
otan
exp
erim
enta
l sci
ence
, but
m
ater
ials
and
pro
cess
es th
at a
re re
leva
nt to
ast
roph
ysic
s can
be
pro
duce
d an
d st
udie
d in
the
lab:
Hyd
rody
nam
ics a
nd sh
ock
phys
ics
EOS
Mat
eria
ls -
dust
; PA
Hs
Ato
mic
phy
sics
and
radi
atio
n tra
nspo
rt
Mag
netic
reco
nnec
tion
>> C
ode
valid
atio
n
But
pro
blem
of s
cale
: tra
de-o
ffs a
mon
g de
nsity
, siz
e, c
olum
n de
nsity
/opt
ical
dep
th
Talk
Out
line
1.Fa
cilit
ies a
nd c
apab
ilitie
s
2.In
ertia
l Con
finem
ent F
usio
n (I
CF)
3.O
MEG
A e
xper
imen
ts: X
-ray
spec
tral d
iagn
ostic
s of I
CF
mat
eria
ls
4.La
bora
tory
ast
roph
ysic
s
5.C
reat
ing
an X
-ray
pho
toio
nize
dne
bula
in th
e la
bora
tory
Cre
atin
g an
X-r
ay p
hoto
ioni
zed
nebu
la
in th
e la
bora
tory
Acc
retio
n on
to c
ompa
ct o
bjec
ts le
ads t
o ph
otoi
oniz
atio
n-do
min
ated
X-r
ay sp
ectr
a
The
circ
umst
ella
rgas
nea
r the
sour
ce o
f har
d x-
rays
is
high
ly io
nize
d--o
verio
nize
dfo
r its
tem
pera
ture
com
pare
d to
cor
onal
equ
ilibr
ium
--an
d pr
oduc
es a
n x-
ray
spec
trum
do
min
ated
by
radi
ativ
ere
com
bina
tion
cont
inua
and
re
com
bina
tion
casc
ades
.
Arti
st’s
con
cept
ion
of a
n ac
cret
ion-
pow
ered
X-r
ay b
inar
y.
A n
ew g
ener
atio
n of
X-
ray
tele
scop
es (C
hand
ra
pict
ured
her
e) is
pr
oduc
ing
high
-re
solu
tion
X-r
ay sp
ectra
fo
r the
firs
t tim
e.
The
cond
ition
s in
the
plas
ma
in p
roxi
mity
to th
e co
mpa
ct
obje
ct a
re t
radi
tiona
lly d
escr
ibed
by
the
ioni
zatio
n pa
ram
eter
(flu
x/de
nsity
), w
hich
is a
mea
sure
of t
he
dom
inan
ce o
f rad
iatio
n pr
oces
ses o
ver c
ollis
iona
lpr
oces
ses.
Con
tour
s of c
onst
ant i
oniz
atio
n pa
ram
eter
(lo
garit
hmic
, in
cgsu
nits
) are
show
n fo
r the
HM
XR
B
Vel
a X
-1 (a
bove
, rig
ht; F
igur
e fr
om S
ako
et a
l. A
p.J.,
52
5, 9
21 (1
999)
).
Mot
ivat
ion
With
the
adve
nt o
f hig
h-re
solu
tion
(λ/∆
λ~
1000
) x-r
ay
spec
trosc
opy
in th
e la
st se
vera
l yea
rs, a
wea
lth o
f sp
ectro
scop
ic d
ata
for p
hoto
ioni
zed
sour
ces h
as b
een
gene
rate
d, a
nd th
e le
vel o
f det
ail a
nd a
ccur
acy
dem
ande
d of
m
odel
s has
incr
ease
d dr
amat
ical
ly.
By
prod
ucin
g an
d m
easu
ring
a w
ell-c
hara
cter
ized
x-r
ay
phot
oion
ized
plas
ma
in th
e la
bora
tory
, we
hope
to
benc
hmar
k th
e co
des u
sed
to m
odel
x-r
ay sp
ectra
of a
ctiv
e ga
lact
ic n
ucle
i, x-
ray
bina
ries,
and
othe
r ast
roph
ysic
al
sour
ces f
or w
hich
pho
toio
niza
tion
dom
inat
es c
ollis
iona
lio
niza
tion.
Cal
cula
tion
of ir
on e
mis
sion
spec
trum
for a
pho
toio
nize
dpl
asm
a (le
ft) a
nd a
col
lisio
nalp
lasm
a (r
ight
). T
houg
h th
e io
niza
tion
dist
ribut
ion
is th
e sa
me
in b
oth
mod
els,
the
spec
tra a
re q
uite
di
ffer
ent (
and
the
phot
oion
ized
plas
ma
is m
uch
cold
er).
(Fig
ure
take
n fr
om L
ieda
hlet
al.
Ap.
J., 3
50, L
37 (1
990)
.)
Plas
mas
dom
inat
ed b
y co
llisi
ons a
nd th
ose
dom
inat
ed b
y ph
otoi
oniz
atio
nha
ve v
ery
diff
eren
t spe
ctra
The
expe
rimen
tal p
acka
ge c
onsi
sts o
f a
cm-s
cale
neo
n-fil
led
cell
with
myl
arw
indo
ws,
mou
nted
seve
ral c
m fr
om th
e Z-
mac
hine
’s c
urre
nt re
turn
can
, ins
ide
of
whi
ch is
the
pinc
h its
elf.
Ulti
mat
ely,
we
plan
on
mak
ing
sim
ulta
neou
s, tim
e-re
solv
ed a
bsor
ptio
n an
d em
issi
on sp
ectro
scop
ic
mea
sure
men
ts o
f the
gas
cel
l, w
hich
can
be
fille
d w
ith a
var
iety
of g
ases
, in
clud
ing
mix
ture
s. Th
e ab
sorp
tion
spec
trosc
opy
uses
the
pinc
h its
elf a
s a
back
light
er.
Expe
rimen
ts a
lread
y co
mpl
eted
hav
e us
ed 3
0 To
rrne
on (n
ion
~ 10
18cm
-3)
obse
rved
in a
bsor
ptio
n w
ith a
tim
e-in
tegr
ated
spec
trom
eter
.
Expe
rimen
tal s
et-u
p
Vie
wfa
ctor
sim
ulat
ions
of t
he p
inch
and
targ
et a
re u
sed
to
calc
ulat
e th
e in
cide
nt sp
ectru
m o
n th
e ga
s cel
l, an
d al
so to
in
vest
igat
e th
e sp
atia
l uni
form
ity o
f the
irra
dian
ce o
n th
e ce
ll.
gas
cell
Tem
pera
ture
(lef
t) an
d de
nsity
(rig
ht) a
t fou
r diff
eren
t tim
es in
the
sim
ulat
ion
of o
ur e
xper
imen
ts.
The
radi
atio
n is
inci
dent
from
the
left.
The
in
itial
neo
n ga
s den
sity
is 1
018cm
-3.
Not
e th
e sh
ock
wav
es la
unch
ed fr
om
the
myl
arw
alls
at l
ate
times
. N
ote
also
the
radi
atio
n w
ave
(as e
vide
nced
by
the
tem
pera
ture
gra
dien
t) tra
vers
ing
the
gas a
t t=1
00 n
s.
Hyd
ro si
mul
atio
ns o
f the
gas
cel
l
A se
ctio
n of
our
raw
dat
a (a
bove
). N
ote
the
very
hi
gh p
rinci
ple
quan
tum
num
ber l
ines
of H
e-lik
e ne
on.
Bac
klit
abso
rptio
n sp
ectru
m (t
ime
inte
grat
ed)
The
time-
inte
grat
ed
abso
rptio
n sp
ectru
m
from
our
firs
t rou
nd
of sh
ots (
top)
are
w
ell-m
atch
ed b
y ou
r ca
lcul
atio
ns (b
otto
m).
A sp
ectra
l sim
ulat
ion
of n
eon,
bas
ed o
n a
repr
esen
tativ
e hy
dro
calc
ulat
ion.
Th
e in
trins
ic sp
ectru
m (l
eft)
show
s num
erou
s lin
es o
f B-li
ke th
roug
h H
-like
ne
on, a
s wel
l as a
reco
mbi
natio
n ed
ge (n
ear 1
200
eV) a
nd re
com
bina
tion
and
free
-fre
e co
ntin
ua.
At 2
eV
(cen
ter)
and
5 e
V(r
ight
) spe
ctra
l res
olut
ion,
m
any
of th
e fe
atur
es a
re b
lend
ed.
The
2 eV
reso
lutio
n sp
ectru
m is
pro
babl
y go
od e
noug
h to
qua
ntita
tivel
y te
st a
tom
ic/s
pect
ral m
odel
s, w
here
as a
lot o
f in
form
atio
n is
lost
at a
reso
lutio
n of
5 e
V.
In th
e ne
xt ro
und
of e
xper
imen
ts, w
e’ll
also
mea
sure
em
issi
on sp
ectra
•Abs
orpt
ion
spec
tra c
an b
e m
easu
red
in th
is c
onfig
urat
ion;
•Ion
izat
ion
para
met
ers o
f ~10
0 sh
ould
be
achi
evab
le a
t n i
on~1
017cm
-3;
•Mea
sure
men
t of r
ecom
bina
tion
spec
tra a
nd a
ccur
ate
wav
elen
gths
of i
nner
-she
ll tra
nsiti
ons s
houl
d be
pos
sibl
e in
th
e ne
xt ro
und
of e
xper
imen
ts.
Prel
imin
ary
Con
clus
ions
for G
as
Cel
l Exp
erim
ents
Con
clus
ions
-Big
nat
iona
l lab
faci
litie
s pro
vide
uni
que
capa
bilit
ies f
or p
lasm
a ph
ysic
s, fu
sion
, and
ast
roph
ysic
s res
earc
h; a
nd a
re a
vaila
ble
toth
e w
ider
(uni
vers
ity) c
omm
unity
-X-r
ay sp
ectro
scop
y ca
n be
use
d to
eff
ectiv
ely
diag
nose
com
plex
, tim
e-va
riabl
e pl
asm
a pr
oper
ties
-But
sign
ifica
nt m
odel
ing
mus
t be
perf
orm
ed in
ord
er to
pro
perly
inte
rpre
t the
se d
ata
(and
des
ign
the
expe
rimen
ts)
-Ast
roph
ysic
ally
mea
ning
ful r
esul
ts c
an b
e ob
tain
ed in
the
labo
rato
ry, b
ut c
are
mus
t be
take
n
-Mak
ing
cont
rolle
d fu
sion
hap
pen
is g
oing
to b
e ve
ry, v
ery
diff
icul
t