Seyda Ipek UC Irvine

Baryogenesis and Particle—Antiparticle Oscillations

SI, John March-Russell, arXiv:1604.00009 Sneak peek • There is more matter than antimatter - baryogenesis • SM cannot explain this

• There is baryon number violation • Not enough CP violation • No out-of-equilibrium processes

• CP violation is enhanced in particle—antiparticle oscillations • Can these oscillations play a role in baryogenesis?

Seyda Ipek (UCI) 2 There is more matter than antimatter

⌦ 0.69 ⇤ ⇠ ⌦ 0.27 DM ⇠ ⌦ 0.04 B ⇠ number of baryons:

n n ¯ ⌘ = B B n

10 CMB 6 10 ' ⇥ PDG

Seyda Ipek (UCI) 3 How Fermilab produces its baryons

Seyda Ipek (UCI) 4 How the Universe would do

Need to produce 1 extra quark for every 10 billion antiquarks! Sakharov Conditions Sakharov, JETP Lett. 5, 24 (1967) Three conditions must be satisﬁed: 1) Baryon number (B) must be violated ✔ can’t have a baryon asymmetry w/o violating baryon number! 2) C and CP must be violated a way to differentiate matter from antimatter ✘ 3) B and CP violating processes must happen out of equilibrium equilibrium destroys the produced baryon number ✘

Seyda Ipek (UCI) 5 We need New Physics

Couple to the SM

Extra CP violation

Some out-of-equilibrium process

Seyda Ipek (UCI) 6 Old New Physics

First-order phase transition Extra scalar ﬁelds CP violation in the scalar sector 2HDM, MSSM, NMSSM, … Out-of-equilibrium decays Leptogenesis CP violation from interference Heavy right-handed neutrinos,…of tree-level and loop processes

Asymmetry Asymmetry in the in the dark sector visible sector asymmetric dark matter + Afﬂeck-Dine Seyda Ipek (UCI) 7 We need New Physics

Couple to the SM Let’s re-visit SM CP violation Extra CP violation

Some out-of-equilibrium process

Seyda Ipek (UCI) 8 CP Violation in Neutral Meson Mixing

We see SM CP violation through neutral meson mixing

K K Bd Bd Bs Bs D D

• A few Nobel prizes • CKM matrix Are particle—antiparticle oscillations special for CP • Top quark violation?

Seyda Ipek (UCI) 9 Particle—Antiparticle Oscillations

Take a Dirac fermion with an approximately broken U(1) charge m = M + ( c + c) Lmass 2 Dirac mass Majorana mass with interactions = g XY + g c XY +h.c. Lint 1 2 We will want the ﬁnal state XY : pseudo-Dirac fermion to carry either baryon or lepton number Seyda Ipek (UCI) 10 Particle—Antiparticle Oscillations

Mm M = i mM Hamiltonian: H = M ✓ ◆ 2 12rei i ' 2 re 1 ✓ ◆

c g2 eigenvalues: H,L = p q r = | | 1 g ⌧ | i | i ± | i | 1| mass states ≠ interaction states OSCILLATIONS!

Seyda Ipek (UCI) 11 Particle—Antiparticle Oscillations 1.0

0.8 important parameter: 1/ 0.6 m x Probability 0.4 ⌘ 1/m 0.2 m = M M 2m H L ' 0.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 time Goldilocks principle for oscillations x 1 x 1 x 1 ⇠ ⌧ Too fast Just right To o s l o w

Seyda Ipek (UCI) 12 CP Violation in Oscillations

c c 1 ( / f) ( / f¯) ✏ = dt ! ! ( / c f)+( / c f¯) Z0 ! !

g2 10-1 For r = | | 1 g ⌧ r =0.1 | 1| -2 sin =0.5 10 2xrsin ✏ -3 2 ϵ 10 ' 1+x

10-4 exact approximation CP violation is 10-5 10-4 10-2 1 100 104 maximized for x ~ 1 x = 2m / Γ

Seyda Ipek (UCI) 13 CP Violation ✔

2xrsin ✏ ' 1+x2 Baryon Number Violation ✔

e.g. RPV SUSY Say the ﬁnal state f has baryon number +1 gudd˜ Baryon asymmetry is produced due to oscillations and decays:

n n ¯ = ✏ n B B

Seyda Ipek (UCI) 14 How to decay out of thermal equilibrium?

Oscillations in the early Universe?

Seyda Ipek (UCI) 15 Oscillations in the early Universe are complicated M 300 GeV 1 ⇠

10-2

Rates (eV) Hubble rate 10-4

Big Bang? 10-6

1 10 100 z = M/T Time

Seyda Ipek (UCI) 16 Oscillations in the early Universe are complicated M 300 GeV 1 ⇠

10-2

Rates (eV) Hubble rate 10-4

Decay rate Big Bang? 10-6

1 10 100 z = M/T Time Out-of-equilibrium decay: H(T M) . ⇠ Seyda Ipek (UCI) 17 Oscillations in the early Universe are complicated M 300 GeV 1 ⇠ Oscillations start when 10-2 !osc >H Rates (eV) Hubble rate 10-4

ωosc = 2m

Decay rate Big Bang? 10-6

1 10 100 z = M/T Time Out-of-equilibrium decay: H(T M) . ⇠ Seyda Ipek (UCI) 18 Oscillations in the early Universe are complicated

Particles/antiparticles are 1 ¯ a ¯ in a hot/dense plasma scat = 2 f af with interactions L ⇤

Seyda Ipek (UCI) 19 Oscillations in the early Universe are complicated

What if interactions can tell the difference between a particle and antiparticle?

Quantum Zeno effect

Oscillations delayed till

!osc > ann, scat

Seyda Ipek (UCI) 20 Oscillations in the early Universe are complicated M 300 GeV 1 Annihilation rate ⇠ Elastic scattering rate

10-2

Rates (eV) Hubble rate 10-4

ωosc = 2m

Decay rate Big Bang? 10-6

1 10 100 z = M/T Time oscillations are further delayed Seyda Ipek (UCI) 21 Oscillations in the early Universe are complicated

Described by the time evolution of the density matrix

Vanishes if scatterings Oscillations are ﬂavor blind dY zH = i HY YH† ± [O , [O , Y]] dz 2 ± ± 1 ¯ 2 s v Y,O YO Yeq h i± 2{ ± ±} ✓ ◆ H : Hamiltonian Annihilations Y: Density matrix O = diag(1, 1) z = M/T not redshift! ± ± Seyda Ipek (UCI) 22 Oscillations + Decays 6 M = 300 GeV, = 10 eV (z) Y Y c : particle asymmetry ⌘ 0.000014 m = 5 x 10-6 eV, x = 10 Symmetric initial 0.000012 m = 2 x 10-6 eV, x = 4 conditions: (0) = 0 0.00001 m = 0.25 x 10-6 eV, x = 0.5 8. × 10-6 r =0.1 Oscillations are delayed Δ(z) 6. × 10-6 sin =0.5 for smaller m

4. × 10-6

2. × 10-6

0 Smaller asymmetry 0 10 20 30 40 50 z =z M/T m (z)=✏ Y (1) exp sin2 eq 2H(z) 2H(z) ✓ ◆ ✓ ◆ Seyda Ipek (UCI) 23 Oscillations + Decays + Annihilations/Scatterings

Two types of interactions

ﬂavor-blind ﬂavor-sensitive c : ! L ! L L !L e.g. scalar e.g. vector 1 1 = ¯ ff¯ = ¯ µ f¯ f L ⇤2 L ⇤2 µ

f : (massless) fermion ⇤: interaction scale Seyda Ipek (UCI) 24 Elastic scatterings/Annihilations delay oscillations

Ignoring decays, particle asymmetry is given by

2 d (y) d(y) 2 2 +2⇠! + ! (y)=0 y = z dy2 0 dy 0 z = M/T S V m ann/scat (z) Y Y c !0 , ⇠ ⌘ ⌘ yH ⌘ 2m

⇠ 1 overdamped, no oscillations ⇠ < 1 underdamped, system oscillates

Seyda Ipek (UCI) 25 Elastic scatterings/Annihilations delay oscillations ﬂavor-sensitive interactions ﬂavor-blind interactions !osc = scat(zosc) !osc = ann(zosc)

when 100 oscillations 50 start

zzoscosc 10

0 =1fb

0 = 1 ab

1 10-6 10-4 10-2 1 z = M/T mass differencem (eV) (eV) Seyda Ipek (UCI) 26 Oscillations + Decays + Annihilations/Scatterings

⌃(z) Y + Y c : total number of particles ⌘ M = 300 GeV 10-3 6 m 2 10 eV ⇥ 6 No annihilation = 10 eV 10-6 <σv>=10-2 ab Σ(z) sin =0.5 <σv>=1 ab r =0.1 0.3 -9 10 ⌘

10-12 1 10 100 ﬂavor-sensitive z = zM/T Seyda Ipek (UCI) 27 Oscillations + Decays + Annihilations/Scatterings m (z) ✏ Y (z )exp sin2 ' eq osc 2H(z) 2H(z) ✓ ◆ ✓ ◆ M = 300 GeV -3 No annihilation 10 6 m 2 10 eV <σv>=10-2 ab ⇥ 6 <σv>=1 ab = 10 eV 10-6 sin =0.5 Δ(z) r =0.1 0.3 -9 10 Oscillations are delayed

10-12 1 10 100 Smaller asymmetry z = M/Tz Seyda Ipek (UCI) 28 How about baryon asymmetry?

1 Annihilation rate Annihilations freeze-out 10-2 z 20 f ' Hubble rate -4 Rates 10 (eV) ωosc

10-6 Decay rate

10-8

1 5 10 50 100 z = M/T

Seyda Ipek (UCI) 29 How about baryon asymmetry?

1 Annihilation rate Elastic scattering rate Annihilations freeze-out 10-2 z 20 f ' Hubble rate -4 Rates 10 Oscillations start (eV) ωosc zosc 60 10-6 ' Decay rate

10-8

1 5 10 50 100 z = M/T

Seyda Ipek (UCI) 30 How about baryon asymmetry?

1 Annihilation rate Elastic scattering rate Annihilations freeze-out 10-2 z 20 f ' Hubble rate -4 Rates 10 Oscillations start (eV) ωosc zosc 60 10-6 ' Decay rate Annihilations are

10-8 Boltzmann suppressed 1 5 10 50 100 ann ⌧ z = M/T Oscillate a few times Produce the baryon asymmetry

10 ⌘ ✏ ⌃(z ) 10 ' osc ⇠ Seyda Ipek (UCI) 31 Let there be baryons!

dB(z) ✏ For z>zosc baryon asymmetry is given by: ⌃(z) dz ' zH

Flavor-sensitive 10-3 ⌃(z)

M = 300 GeV 2 6 0 = 10 ab m =2 10 eV 10-6 ⇥ 6 BARYONS!!! = 10 eV = 1 ab = ⇡/6 0 Abundancies -9 (z) 10 ⌘

B(z) 10-12 1 10 100 z = M/Tz = Y Y : baryon asymmetry B B B Seyda Ipek (UCI) 32 My history of the Universe hot 1014 K 1013 K 1010 K 3,000 K

Temperature

p n n p

p n

n p n Inﬂation BigBang p n p n p n Equal number Antiparticles of particles and Particles decay turn into antiparticles into protons Atoms, particles stars, Time and neutrons galaxies… are formed

1 ns 10 ns 1 s 300,000 13.7 billion years years Seyda Ipek (UCI) 33 What kind of model?

Oscillations Pseudo-Dirac fermions

Approximately broken U(1) symmetry

DM theories with a global U(1) ?

global symmetries are broken by gravity

Seyda Ipek (UCI) 34 Hall, Randall, Nuc.Phys.B-352.2 1991 Kribs, Poppitz, Weiner, arXiv: 0712.2039 Frugiuele, Gregoire, arXiv:1107.4634 SI, McKeen, Nelson, arXiv: 1407.8193 SI, John March-Russell, arXiv:1604.00009 Pilar Coloma, SI, arXiv:1606.06372 My favorite model for everything!

U(1)R -symmetric SUSY

Has Dirac gauginos Dirac gauginos are awesome - less tuning for heavier stops Solves SUSY CP and ﬂavor problems, …

Seyda Ipek (UCI) 35 U(1)R symmetric SUSY

Sfermions have +1 R-charge

Fields SU(3)c SU(2)L U(1)Y U(1)R Q =˜q + ✓ q 3 2 1/6 1 U¯ = u¯˜ + ✓ u¯ 3¯ 1 -2/3 1 D¯ = d¯˜+ ✓ d¯ 3¯ 1 1/3 1 ¯ D¯ = D¯ + ✓ D¯ 3 1 1/3 1 D = D + ✓ D 3 1 -1/3 1 W ˜ B˜ 1 1 0 1 B,↵ ↵ S = s + ✓ S 1 1 0 0

Bino has +1 R-charge (pseudo)-Dirac Singlino (S) has -1 R-charge gauginos!

Seyda Ipek (UCI) 36 U(1)R symmetric SUSY

New superﬁelds non-gauge couplings for Dirac partners

Seyda Ipek (UCI) 37 Pseudo-Dirac gauginos Take the bino and the singlino: Fox, Nelson, Weiner, hep-ph/0206096 B˜ (1, 1, 0) +1 ˜ ˜ ⌘ mass MD BS + MD⇤ B†S† S (1, 1, 0) 1 L ⌘ U(1)R must be broken …because (anomaly mediation) (g) m = F B˜ g (Small) Majorana mass some conformal for the bino parameter 3 m3/2 2 2 . F . m3/2 16⇡ MPl | | Arkani-Hamed, et al, hep-ph/0409232

Seyda Ipek (UCI) 38 SUSY CP Problem

Electron electric dipole moment: de ≤ 0.87x10-28 e⋅cm ACME, Science 343 (2014)

What we have in the SM: What SUSY has: � �

e e ╳ EW loop ╳ eL e˜L e˜R eR de ≤ 10-38 e⋅cm SUSY CP problem

Seyda Ipek (UCI) 39 SUSY CP Problem: Solved

Due to the UR(1) symmetry: • No (very small) Majorana gaugino masses • No left-right mixing for sfermions

�

(similar story for the ╳ ﬂavour problem)

╳ eL e˜L e˜R eR

We can have large CP violating parameters w/o affecting EDMs

Seyda Ipek (UCI) 40 Pseudo-Dirac bino oscillations 1 Mass terms: mass MDBS + m ˜ B˜B˜ + mSSS +h.c. L ! 2 B ⇣ ⌘ Let’s also consider R-parity violation ˜ ¯¯ ¯¯ e↵ = GB˜ B u¯dd + GSS u¯dd +h.c. L gY 00 gS 00 GB 2 GS 2 ⇠ msf ⇠ m Remember from before: m = M + ( c + c) Lmass 2 with interactions bino antibino = g XY + g c XY +h.c. Lint 1 2 udd udd Seyda Ipek (UCI) 41 Pseudo-Dirac bino oscillations

Oscillation Hamiltonian:

i MD m i 12re = i H mMD 2 2re 1 ✓ ◆ ✓ ◆ 5 M 2 GS G ˜ r = | | 1 3 B G ˜ ⌧ ' (32⇡) | | | B| with annihilations + elastic scatterings: 2 gY ¯ ¯ µ scat = 2 µPL F (gV + gA5)F L msf ﬂavor sensitive, oscillations are Y 2 Y 2 fL g = R ± L F = delayed, etc etc V,A f † 2 ✓ R ◆ Seyda Ipek (UCI) 42 Let there be baryons!

10-3 ⌃(z)

M = 300Σ(z) GeV 6 m 2 10 eV 10-6 Δ⇥(z) 6 = 10 eV ΔB(z) = ⇡/6,r=0.1 msf = 20 TeV Abundancies -9 10 (z) msf = 10 TeV

B(z) 10-12 1 10 100 z = zM/T BARYONS!!!

Seyda Ipek (UCI) 43 Outlook

•Sfermions are a few TeV (no lighter than ~ 3 TeV) •O(100 GeV - TeV) particles Colliders! •Decay rate < 10-4 eV travels > mm displaced vertices! •How about lepton number violation? same-sign lepton asymmetry? •Connection to asymmetric DM? Seyda Ipek (UCI) 44 backup slides

Seyda Ipek (UCI) 45 Time dependent oscillations

q c (t) = g+(t) g (t) , | i | ip | i c c p (t) = g+(t) g (t) | i | i q | i

1 im t 1 t im t 1 t g (t)= e H 2 H e L 2 L ± 2 ± ⇣ ⌘

Seyda Ipek (UCI) 46 Oscillations+Decays

d2(y) d(y) +2⇠! + !2 (y)= ✏!2 ⌃(y) dy2 0 dy 0 0

For: ⌃(z)=2Y (1) exp for z>1 eq 2H(z) ✓ ◆ Solution is m (z) A ✏Y (1) exp sin2 + ' eq 2H(z) 2H(z) ✓ ◆ ✓ ◆

Seyda Ipek (UCI) 47 Different mass difference

M = 300 GeV

= ⇡/6,r=0.1

0 = 1 ab 4 10-6 = 10 eV

5 -8 = 10 eV ΔB 10

6 = 10 eV 10-10

7 = 10 eV 10-12 10-6 10-4 10-2 1 m (eV)

Seyda Ipek (UCI) 48 Oscillation start times Hubble 2 10 6 eV M z 6 ⇥ osc ⇠ m 300 GeV r ✓ ◆ Flavor-blind

3 6 7 M 2 10 eV 0 zosc ln 10 ⇥ ⇠ " 300 GeV m 1fb # ✓ ◆ ✓ ◆ ⇣ ⌘ Flavor-sensitive 3/5 6 1/5 1/5 M 2 10 eV z 80 ⇥ 0 osc ' 300 GeV m 1fb ✓ ◆ ✓ ◆ ⇣ ⌘ Seyda Ipek (UCI) 49 Elastic scatterings delay oscillations 1

M 300 GeV scattering rate v =1fb ⇠ annihilation rate h i 10-2

Hubble rate Rates 10-4 (eV) ωosc = 2m

10-6 Decay rate Big Bang?

10-8 1 5 10 50 100 500 z = M/T Time

Seyda Ipek (UCI) 50