amo adventures at the lcls - advanced photon source€¦ · 2×1013 photons per pulse at 750 ev;...
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AMO Adventures at the LCLS
TheArgonneAtomic,Molecular,andOp6calPhysicsGroup’sexperimentsu6lizingtheLinacCoherentLightSource(LCLS)−thefirstX‐rayFree‐ElectronLaser
BertoldKrässigChemicalSciencesandEngineeringDivision(soon:X‐RayScienceDivision)ArgonneNaAonalLaboratory
APS/UsersMonthlyOperaAonsMeeAng,December16th,2009
Thanks to 33 Undulators from the APS
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X-Ray Flux: Per Pulse versus Per Second
LCLS:2×1012photonsperpulseat9keV;
2×1013photonsperpulseat750eV;
≈70‐300femtosecondspulselength
(≈1‐3femtoseconds,ifthebunchchargeisloweredfrom250pCto20pC)currently30HzrepeAAonrate,120Hzmaximum:
≤2.4×1015photonspersecond
Forcomparison,APS14‐ID(2undulators):
1010photonsperpulseat12keV;≈100picosecondspulselength;
6.5MHz,mechanicallylimitedto≤1kHz:
≤6.5×1016photonspersecond
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High Intensity X-rays
2×1013photons 750eVphotonenergy 200fspulselength 1μm2focaldiameter 1.2×1018W/cm2
Pulsesarespiky−>peakintensiAesarehigherthantheaverage IndividualatomsabsorbmulAplephotonsduringasinglepulse
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“Unlocking the World of the Ultra Small and the Ultra Fast”
AMOquesPons
fundamentalnatureofx‐raydamageathighintensity– electronicdamage
– CoulombexplosionAmescale
– behaviorat>1018W/cm2–15Å
nonlinearx‐rayprocesses
roleofcoherence
quantumcontrolofinner‐shellprocesses
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Before During ~10 fs After ~50 fs
Neutze,Wouts,vanderSpoel,Weckert,HajduNature406,752(2000)
3x1012 x-rays 100 nm spot 12 keV
10 fs ⇒ 1022 W/cm2
TheLCLSPosterChild
The First Endstation: AMO Physics
KBmirrors
HighFieldPhysicsChamber
Diagnos6csChamber
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The Components of the High Field Chamber
ionTOF
5eTOFsforangulardistribu6ons
Negasjet
JohnBozekChristophBostedt
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The First User Experiment , October 1−5, 2009 Tracking transient atomic states produced by ultraintense x-ray pulses
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TheTeamYuelinLi,ElliotKanter,BertoldKrässig,AnneMarieMarch,StevePram,
RobinSantra,SteveSouthworth,LindaYoungArgonne
JohnBozek,ChristophBostedt,MarkMesserschmidtLCLS
LouDiMauro,GillesDoumy,ChrisRoedigOhioStateUniversity
NoraBerrah,LiFang,MamhiasHönerWesternMichiganUniversity
PhilBucksbaum,JamesCryan,MikeGlownia,DavidReisPulseCenter,Stanford
Collaborators
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200 600 1000 1400 1800
photon energy (eV)
0.01
0.1
1
cro
ss s
ectio
n (
Mb
)
Ne photoabsorption
Neon, the Prototypical Atom
10electrons,groundstateconfiguraAon1s22s22p6
Bindingenergiesinneutralneon:
2p:21.6eV2s:48.5eV
1s:870.2eV
Thehigherthechargestate,thehigherthebindingenergies.
Atthreshold,thephotoabsorpAoncrosssecAonforthe1sshellis15Ameslargerthanforthevalenceshell.
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K-Shell Ionization (870 eV and above) Auger Decay
K‐holestatelifeAmeτ=2.4fs
PredominantlyAugerdecay(98.2%)
K‐shellholeisfilledbyavalenceelectronandasecondvalenceelectronisemimed(Augerelectron)
Augerelectronenergyisthebindingenergydifferencebetweentheinnerandvalenceshells
DoubleK‐holes(hollowatom)giverisetohypersatellitetransiAons
Double‐K/Single‐K=0.32(4)%(for5keVx‐rays,single‐photonabsorpAon,12‐ID)
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Southworth et al., Phys. Rev A 67 (2003)
Theory: Nina Rohringer and Robin Santra Phys. Rev. A 76, 033416 (2007)
P:K‐shellphotoionizaAon
A:Augerelectronemission
V:ValenceionizaAon SequenAalionizaAonPAVVVV…
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1013x‐rays230fs1µmspot
The “First Glimpse at the Experimental Data” will be posted after publication of this work
Thankyouforyourunderstanding.
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The Fifth Experiment at LCLS, Oct 30− Nov 3, 2009 Resonant nonlinear x-ray processes at high x-ray intensity
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TheSameTeamYuelinLi,ElliotKanter,BertoldKrässig,AnneMarieMarch,StevePram,
RobinSantra,SteveSouthworth,LindaYoungArgonne
JohnBozek,ChristophBostedtLCLS
LouDiMauro,GillesDoumy,ChrisRoedigOhioStateUniversity
NoraBerrah,LiFang,MamhiasHönerWesternMichiganUniversity
PhilBucksbaum,JamesCryan,MikeGlownia,DavidReisPulseCenter,Stanford
Schematic of the Two-photon 1s-2p Resonance Excitation
a) ValenceionizaAonbyfirstabsorbedx‐rayphoton(orIRlaser)b) 1s‐2pexcitaAonat848.6eVbysecondabsorbedphoton;
resonantabsorpAon/sAmulatedemissioncyclingathighintensity(RabiFlopping)
c) Augerdecay
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Theory: Nina Rohringer and Robin Santra, Phys. Rev. A 77, 053404 (2008)
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Single shot
average
Summary and Outlook
TheLCLSisupandrunning. TheArgonneAMOgrouphadtwosuccessfulexperimentsat
theLCLSinOctober2009.
Thedatashowthesignaturesof– sequenAalmulAphotonabsorpAon,– doubleK‐hole(hollowneon)producAon,– intensity‐inducedtransparency/saturableabsorpAon,– 1s‐2presonantabsorpAon.
Dataanalysisisongoing. Ournextrun:August1‐5,2010.Femtosecondx‐raytwo‐photonphotoelectronspectroscopyof
organicmolecules
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Heroes at the Main Control Center
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