Low-energy QED tests (and what we can learn from them)

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Barbara Nicholson
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1 Low-nrgy QED tsts (and what w can larn from thm) (0γ) 2γ (4γ) (1γ) 3γ (5γ) Indirct Sarchs for Nw Physics at th tim of LHC Flornc, March 2010 Andrzj Czarncki U. of Albrta & CERN

2 Outlin Gyromagntic factors and th dtrmination of fundamntal constants (α, m ) Polylctrons and tsts of fw-body QED (0γ) 2γ (4γ) (1γ) 3γ (5γ) Muonic atoms and nw physics sarchs (lpton flavor violation, nw wak-scal forcs)

3 Gyromagntic factors and th dtrmination of * th lctron mass * th fin structur constant

4 Fr-lctron g-factor α =1/ ( 51) [ 0.37 ppb] If you rmmbr thr dcimal placs, , you gt anothr thr fr!

5 Fr-lctron g-factor Exprimntal and thortical uncrtaintis: α =1/ ( 33)( 39) [ 0.37 ppb]

6 Motion in th Pnning trap Motion in th xy plan:

7 Bound-lctron g-2: masurmnt From Wrth M and m hav diffrnt origins!

8 Bound-lctron g-2: thory ( Zα) ( Zα) g = 2 + O Z = Z ( α) ( α) 6 2 Brit 1928 Dirac thory Not: Brit s calculation prdats Schwingr s by 20 yars

9 Bound-lctron g-2: thory g ( Zα) ( Zα) = 2 + O Z 3 6 ( α ) 6 ( Zα ) 2 α ( Zα) a41 ln + a O Z π 6 ( Zα ) ( α) 4 5 on-loop corrctions Pachucki, Jntschura, Yrokhin 2004

10 Bound-lctron g-2: thory g ( Zα) ( Zα) = 2 + O Z 3 6 ( α ) 6 ( Zα ) 2 α ( Zα) a41 ln + a O Z π 6 ( Zα ) ( α) 4 5 ( Zα ) 2 2 α ( Zα ) b41 ln b π 6 ( Zα ) two-loop corrctions

11 Th two-loop bound-stat ffct b b = 9 = 16.4 Pachucki, AC, Jntschura, Yrokhin 2005 ( ) = ( 29) ( 1) m C u xp th Thortical rror: ngligibl

12 2010: nw masurmnt with oxygn, 16 O 7+ Thortical prdiction: th g Z = = Masurd valu: ( ) ( ) xp g Z = = ( ) ( ) (prliminary)

13 Th kinmatic mthod of finding alpha Rydbrg constant is xtrmly wll masurd, R = mc 2 α V hc hc W can find alpha if w masur th quotint of th Planck constant and th lctron mass, In practic havir particls ar bttr: nutrons or atoms. 2 α = = 2h R mc 2R m p mcs h c m m m p Cs

14 Fin structur constant: othr mthods Natur 442 (2006) 516. ν ν ' Rb 2 α = = 2h Ry mc 2Ry mp mrb h c m m m p Rb h ( ν ν ') h m Rb = 2 2 2h ν 2 m c Rb Δν c 2 2ν 2

15 α from Paris about 450 Bloch oscillations in ach dirction : 1800 rcoils from F. Nz Statistical uncrtainty on α = α -1 = (91) uncrtainty Cladé t al, PRL 96, (2006) Futur goal: 1ppb

16 Polylctrons (0γ) 2γ (4γ) (1γ) 3γ (5γ)

17 Dipositronium Ps (0γ) 2γ (4γ) (1γ) 3γ (5γ) + (0γ) 2γ (4γ) (1γ) 3γ (5γ)

18 Discovry of dipositronium 2007 Molcul formation kills long-livd positronia. At highr tmpratur, fwr atoms on th surfac, fwr molculs formd. Indd: at high-t, mor long-livd positronia obsrvd. Cassidy & Mills, Natur 2007 (0γ) 2γ (4γ) (1γ) 3γ (5γ)

19 Spctrum of th molcul Ps 2 Non-molcular stats of Molcular stats From Suzuki & Usukura, 2000 (0γ) 2γ (4γ) (1γ) 3γ (5γ)

20 A dirct signal of th molcul: transition lin. From Suzuki & Usukura, 2000 Autodissociation forbiddn by Bos-Einstin statistics (0γ) 2γ (4γ) (1γ) 3γ (5γ)

21 A dirct signal of th molcul: transition lin. From Suzuki & Usukura, 2000 Obsrvabl UV transition (0γ) 2γ (4γ) (1γ) 3γ (5γ)

22 Qustions about this transition: with Puchalski, PRL 101, (2008) What is its accurat nrgy? Δ E = E E = P 4.9V S (8) a.u. Similar to atomic positronium, but softr (dilctric ffct?): E P 3 1 ES = a.u.=0.1875a.u. 4 4 (0γ) 2γ (4γ) (1γ) 3γ (5γ)

23 Qustions about this transition: with Puchalski, PRL 101, (2008) How oftn dos radiativ transition appar (bfor annihilation)? ( P S) annih Γdip ( P S) ( P) ( P S) dip ( ) BR = = Γ +Γ (0γ) 2γ (4γ) (1γ) 3γ (5γ)

24 Muonic atoms

25 Muonic hydrogn Lamb shift and th proton radius Slids on this topic ar not includd in this vrsion; plas contact Randolf Pohl for dtaild information about th rcnt PSI rsults.

26 Sarchs for Lpton Flavor Violation W hard ystrday about MEG: now 10-11, goal ~10-13 Muon-lctron convrsion: Frmilab proposal Mu2E: Nw ida: µ Koik t al, , in a larg-z atom. Comptition with muon captur.

27 Muon captur Thory and xprimnt agr, aftr yars of confusion. Avrag of HBChPT calculations of Λ S : Apply nw rad. corrction (2.8%): furthr sub prcnt thory rquird Λ Thory S Thory = S s -1-1 PRL 99, (2007) Λ MuCap S MuCap = S ± stat ± stat sys s sys -1-1

28 Summary Continuing progrss in dtrmination of α and m. Nw opportunitis to tst QED with thr- and four-body bound stats. An opn problm: organization of th prturbativ sris; origin of dominant corrctions.

DIS-Parity. Search for New Physics Through Parity Violation In Deep Inelastic Electron Scattering. The Physics Case

DIS-Parity. Search for New Physics Through Parity Violation In Deep Inelastic Electron Scattering. The Physics Case DIS-Parity Sarch for Nw Physics Through Parity Violation In Dp Inlastic Elctron Scattring Th Physics Cas R. Arnold for th DIS-Parity Collaboration Exprimnt Plan by Stv Rock will follow 12 Jun 2003 DIS-Parity