J.B. Hastings- Science with the LCLS

8/3/2019 J.B. Hastings- Science with the LCLS

1/34

Jerry Hastings APS April 23, 2006

Science with the LCLS

Science with the LCLS

J. B. Hastings

SLAC/SSRL/LUSI


2/34


Palo Alto 1878Palo Alto 1878--18791879


3/34


1878: E. Muybridge at Stanford1878: E. Muybridge at Stanford

E.E. MuybridgeMuybridge,, AnimalsAnimals in Motionin Motion, ed., ed. byby L. S. Brown (Dover Pub. Co., New York 1957).L. S. Brown (Dover Pub. Co., New York 1957).

Tracing motion of animals by spark photographyTracing motion of animals by spark photography

Muybridge and Stanford disagree whether all feet leave the grounMuybridge and Stanford disagree whether all feet leave the ground at oned at one

time during the galloptime during the gallop

E. MuybridgeE. Muybridge


4/34Jerry Hastings APS April 23, 2006

Ultrafastlasers

Synchrotrons

Laser plasmasXFELs

Current lasers:

X-ray sources:

Science:

Acoustic phonons

Vibrations (Optical phonons)Chemistry and BiochemStrings,

CosmologyParticle Collisions

Electron dynamics

Ultrafast Sources and ScienceUltrafast Sources and Science

harpo10-27

yocto10-24

milli10-3

micro10-6

nano10-9

pico10-12

femto10-15

atto10-18

Pulse duration (seconds)

zepto10-21



z

1/3

coherent power

incoherent power

NN 66101099

Powe

r

Wavelength



GENESIS- simulation for TTF parametersCourtesy - Sven Reiche (UCLA)

undulatorentrance

undulatorentrance

half-waysaturation

half-waysaturation

fullsaturation

fullsaturation

Microbunching through SASE ProcessMicrobunching through SASE Process



LCLSLCLSLCLS

1.5-15 1.5-15

2 compressors2 compressors

one undulatorone undulator

X-FEL based on last 1-km of existingSLAC linac



Peak Brilliance of FELsPeak Brilliance of FELs

courtesy T. Shintake

X-Ray

~109 103 by e quality,

long undulators

106 by FEL gainphotonsper

phase-

space

volume

per band-

width

1


10/34


Temporal Characteristics

E(t)=j E0(t-tj), tj is the random arrival time of jth e-

E0: wave packet of a single e-

Nu

uc

Ncl

2

bunch length

Sum of all packets E(t) lc ~ 100-1000 < bunch length


11/34


Atomic, molecular and

optical science

Nano-particle and singlemolecule (non-periodic)imaging

Diffraction studies of

stimulated dynamics(pump-probe)

High energy density science

Coherent-scattering studiesof nanoscale fluctuations

SLAC Report 611

Absorption

ResonanceRaman

t0

t1

t2

t3

t4t5

Aluminum plasma

10-4 10-21

102 10 4

classical plasma

dense plasma

high densitymatter

G =1

Density (g/cm-3)

G =10

G =100

Program developed by

international team of

scientists working withaccelerator and laser

physics communities

t=0

t=

the beginning.... not the end


12/34


Focused beam (100nm):

Formation of Hollow Atoms:

Multiphoton Ionization:

L-edge

Kr photoabsorption

h =900eV2h

h

h

K-edge

Ne Photoionization

h =900eVAll atoms havemultiple core holesper pulse (105 atoms)Auger

=2.5fs

Note effect ~ I2

All atoms experience

multiphoton ionizationper pulse (105 atoms)

Giant Coulomb explosions of Xe clustersAuger rate 1000 times faster thanionization rate

Valence shell is missing - only cores left

Understanding is central to the

imaging of biomolecules

109 atoms

h =950eVAuger

=0.1fs 3p (M3)

Xe


13/34


Structural Studies on Single Particles and Biomolecules

Conventional method: x-ray diffraction from crystal

Proposed method: diffuse x-ray scattering from single protein moleculeNeutze, Wouts, van der Spoel, Weckert, Hajdu Nature406, 752-757 (2000)

Implementation limited by radiation damage:

In crystals limit to damage tolerance is about 200 x-ray photons/2

For single protein molecules need about 1010 x-ray photons/2 (for 2 resolution)

LysozymeCalculated scattering patternfrom lysozyme molecule

LCLS


14/34


Nanocrystal of lysozyme

1 LYSOZYME5x5x5

LYSOZYMES

LCLS

Nanocrystal of lysozyme

562kD


15/34


100 fs

3 x 101150 fs

8 x 101110 fs5 x 1012

5 fs1 x 1013

1 fs5 x 1013

562kDa

2 resolution

Predicted scattering from a single RUBISCO molecule (Relectronic = 15%)

Ultrafast Coherent Single Shot X ray Diffraction


16/34


multilayermirror

CCD

15o

-15o

To beamdump

Incident VUV-FEL pulse:30 fs, 32 nm,3 x 1 013 Wcm-2 1x3 SiN membranewith 200 nm pattern

Pulse #1: Diffraction reveals structurebeforeradiation damage occurs

Pulse #2: Structure was completelydestroyed by pulse #1

Ultrafast Coherent Single Shot X-ray Diffraction

The First Demonstration at the VUV-FEL at DESY

VUV FEL P b E i t M th FEL


17/34


VUV-FEL Pump-probe Experiments Measure the FEL-

induced explosion with 30 fs Time Resolution

zDetector

MultilayerMirror

30 fs pulse(9 m long)

PromptdiffractionDelayed diffraction

Latexparticles

Single shot ultrafast time-delay X-rayhologram, with 300 fs delay

Time delay = 2z/c

The pattern is the interference ofthe waves scattered from theunexploded particle (reference

wave) and the same particleduring explosion. Manyparticles generate speckle also.

Chapman, Hajdu and collaborators


18/34


Scattering experiments


19/34


EOS and PumpEOS and Pump--ProbeProbe

s

ystemresponse

0S 2S3S4S 6S7S 5S8S9S1S time

impulse

Electro-Optic Sampling (EOS) delivers arrival time to users

Pump-Probe experiments now possible at XFELs

Machine jitter exploited to sample time-dependent phenomena

Typical time resolved experiment utilizes intrinsic

synchronization between pump excitation and probe


20/34


~ 200fs

(Typical)Single-Shot EOS Data at SPPS (100m ZnTe)


21/34


Dynamics of high amplitude coherent optical phonons

Bi structure

a a

a


22/34


X-rays diffraction direct probe of atomic motion

111 forbidden in simple cubic 222 perfect in simple cubic

467 fs

Sokolowski-Tinten et al., Nature, 422 (2003)


23/34


Using the jitter @ SPPS for Random Sampling

D. M. Fritz et al. unpublished

U i th jitt @ SPPS f R d S li


24/34


Using the jitter @ SPPS for Random Sampling

N=12463

1.74 mJ/cm2 (absorbed), ~1% f =2.5 THz* A = 0.92 pm = 5pm

Arrival time distribution Sorted normalized data

D. M. Fritz et al. unpublished *precise time calibration still in progress

Measured (Mean) Equilibrium Position


25/34


Measured (Mean) Equilibrium Position

D. M. Fritz et al. unpublished

E i i i i h h b li LCLS


26/34


Exciting science with the baseline LCLS

Atomic physics in a new regime

Potential to collect and invert diffraction patternsfrom single molecules providing atomicresolution

Study directly the atomic scale motions on the timescales of interest to chemistry and materials

science

And MUCH more


27/34


Looking to the future:

Can we get attosecond pulses ??


28/34


Undulator RegimeUndulator Regime

Exponential Gain RegimeExponential Gain Regime

SaturationSaturation

0.2 fs

0.9 fs

1 % of X-Ray Pulse1 % of X-Ray Pulse

Electron BunchMicro-Bunching

Electron Bunch

Micro-Bunching

Select a single spike

~ 300 attoseconds

2.5 fs

Transverse Emittance is Critical for X-ray FEL


29/34


Transverse Emittance is Critical for X ray FEL

< 1< 1m at 1m at 1 , 15 GeV, 15 GeV

courtesy S. Reiche

P = P0NN = 1.2= 1.2 mm

PP == PP00/100/100NN = 2.0= 2.0 mm

Can we spoil most ofthe e bunch andleave 1-fs to lase?

i l b h 1 C 120 H

singlebunch 1 nC 120 Hz


30/34


single bunch, 1-nC, 120-Hzsingle bunch, 1-nC, 120-Hz

SLAC linac tunnelSLAC linac tunnel

LinacLinac--00LL =6 m=6 m

LinacLinac--11LL =9 m=9 mrfrf== 3838



BCBC--11LL =6 m=6 m

RR5656== 36 mm36 mm

BCBC--22LL =22 m=22 m

RR5656== 22 mm22 mm DLDL--22LL =66 m=66 m

RR5656 = 0= 0

DLDL--11LL =12 m=12 mRR5656 00

undulatorundulatorLL =120 m=120 m

7 MeV7 MeVzz 0.83 mm0.83 mm 0.2 %0.2 %

150 MeV150 MeVzz 0.83 mm0.83 mm 0.10 %0.10 %

250 MeV250 MeVzz 0.19 mm0.19 mm 1.8 %1.8 %

4.54 GeV4.54 GeVzz 0.022 mm0.022 mm 0.76 %0.76 %

14.35 GeV14.35 GeVzz 0.022 mm0.022 mm 0.02 %0.02 %

...existing linac...existing linac

new

new

rfrf

gungun

2525--1a1a3030--8c8c

2121--1b1b2121--1d1d XX

LinacLinac--XXLL =0.6 m=0.6 mrfrf==180180

2121--3b3b2424--6d6d

MagneticBunch Compression

MagneticBunch Compression


31/34


Magnetic Bunch CompressionMagnetic Bunch Compression

z0z0

//

zz

zz

under-

compression

under-

compression

V= V0sin()V= V0sin()

RF AcceleratingVoltage

RF AcceleratingRF AcceleratingVoltageVoltage

z =R56/z =R56/

Path Length-EnergyDependent BeamlinePath LengthPath Length--EnergyEnergyDependent BeamlineDependent Beamline

or over-

compression

or over-

compression

//

zz

E/EE/E

//

zz

chirpchirp

2.6mmrm

s

0.1 mm (300 fs) rms

x,ho

rizontalpos

.(mm)

50 m

z, longitudinal position (mm)

Add thin slotted foil in center of chicane

Add thin slotted foil in center of chicaneAdd thin slotted foil in center of chicane


32/34


x DE/E txx DDEE//EE tt2D2Dxx

yy

Add thin slotted foil in center of chicaneAdd thin slotted foil in center of chicaneAdd thin slotted foil in center of chicane

coulombcoulomb

scatteredscatteredee--

unspoiledunspoiled ee--

coulombcoulombscatteredscatteredee--

ee--

1515--mmm thick Be foilm thick Be foilPRLPRL 9292, 074801 (2004, 074801 (2004).P. Emma, M. Cornacchia, K. Bane, Z. Huang, H. Schlarb, G. StupakP. Emma, M. Cornacchia, K. Bane, Z. Huang, H. Schlarb, G. Stupakov, D. Walz (SLAC)ov, D. Walz (SLAC)

zz 60 m60 m


33/34


2 fsec fwhm2 fsec fwhm

xx--rayrayPowerPower

(GW

)

S


34/34


Summary

The fun begins in 2008 -2009and the unexpected is the

most exciting !

Documents

J.B. Hastings- Science with the LCLS