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Home , Baryon asymmetry

Testable Scenarios for the origin of masses &

Jacobo López-Pavón

IFT UAM-CSIC January 21, 2019

Outline

● What we know/don’t know.

● Leptogenesis and Seesaw Model.

● Testable Leptogenesis. Hernandez, Kekic, JLP, Racker, Rius 1508.03676; Hernandez, Kekic, JLP, Racker, Salvado 1606.06719

● Flavor structure & CP violation in minimal model. Caputo, Hernandez, Kekic, JLP, Salvado 1611.05000 Caputo, Hernandez, JLP, Salvado 1704.08721

● Conclusions

What we know in the neutrino sector

What we know.

Atmospheric sector Interference/Reactor Solar sector

What we know.

Atmospheric sector Interference/Reactor Solar sector

(1s)

Esteban, Gonzalez-Garcia, Hernandez-Cabezudo, Maltoni, Schwetz 1811.05487 http://www.nu-fit.org/ What we know.

Atmospheric sector Interference/Reactor Solar sector

(1s)

Esteban, Gonzalez-Garcia, Hernandez-Cabezudo, Maltoni, Schwetz 1811.05487 http://www.nu-fit.org/ What we know.

Atmospheric sector Interference/Reactor Solar sector

(1s)

Esteban, Gonzalez-Garcia, Hernandez-Cabezudo, Maltoni, Schwetz 1811.05487 http://www.nu-fit.org/ What we know.

● Recent results from T2K and NOvA

excluded at 2s

What we still do not know in the neutrino sector

What we don’t know.

CP violation in the lepton sector ? Fukugita, Yanagida 1986 Essential in order to explain the Baryon asymmetry of the via Leptogenesis.

See for instance: King et al 1402.4271 Altarelli et al 1205.5133, 1002.0211 ? The Octant: . Very relevant for the flavour puzzle.

Neutrino ordering ( sign of ) ?

Normal Inverted Ordering Ordering (NO) (IO)

What we don’t know.

CP violation in the lepton sector ? Fukugita, Yanagida 1986 Essential in order to explain the Baryon asymmetry of the universe via Leptogenesis.

See for instance: King et al 1402.4271 Altarelli et al 1205.5133, 1002.0211 ? The Octant: . Very relevant for the flavour puzzle.

Neutrino ordering ( sign of ) ? Extremely relevant input for other observables as decay Normal Inverted Ordering Ordering Absolute neutrino mass scale (NO) (IO) ? Cosmological probes, Tritium beta decay (KATRIN)

? Dirac vs Majorana: decay

mixing

mass of propagating neutrino

Baryon asymmetry

?

Baryon asymmetry

● Observed universe mainly made out of .

● Reasonable assumption: after Big-Bang same amount of matter and generated.

● The observed baryon asymmetry is quoted in terms of the abundance (number-density asymmetry of normalized to the density):

How can this matter asymmetry of our Universe be generated?

Sakharov conditions ● In order to generate the baryon asymmetry the following conditions should be satisfied:

Baryon number violation 1 If baryon asymmetry is conserved, no can be generated

Sakharov conditions ● In order to generate the baryon asymmetry the following conditions should be satisfied:

Baryon number violation 1 If baryon asymmetry is conserved, no baryon number can be generated

OK in Sphalerons the SM @T 140Gev

Sakharov conditions ● In order to generate the baryon asymmetry the following conditions should be satisfied:

C and CP violation 2 If C or CP are conserved:

Sakharov conditions ● In order to generate the baryon asymmetry the following conditions should be satisfied:

C and CP violation 2 If C or CP are conserved:

Exist in the SM

There is CP violation in the quark sector

Sakharov conditions ● In order to generate the baryon asymmetry the following conditions should be satisfied:

C and CP violation 2 If C or CP are conserved:

Exist Jarlskog in the invariant SM too small

There is CP violation Not enough CP violation in the quark sector in SM !!

Gavela, Hernandez Orloff, Pene, Quimbay 1994 Sakharov conditions ● In order to generate the baryon asymmetry the following conditions should be satisfied:

Departure from thermal equilibrium 3 Production/destruction rates of Baryons are equal in thermal equilibrium:

Sakharov conditions ● In order to generate the baryon asymmetry the following conditions should be satisfied:

Departure from thermal equilibrium 3 Production/destruction rates of Baryons are equal in thermal equilibrium:

Exist in the SM

Due to Hubble expansion of the universe

Sakharov conditions ● In order to generate the baryon asymmetry the following conditions should be satisfied:

Departure from thermal equilibrium 3 Production/destruction rates of Baryons are equal in thermal equilibrium:

Exist Deviation in the too small SM

Due to Hubble expansion Not enough deviation from of the universe thermal equilibrium in the SM!!

Kajantie, Laine, Rummukainen, Shaposhnikov, 1996 Observed Baryon asymmetry can not be generated in the SM

Gavela, Hernandez Orloff, Pene, Quimbay 1994 Leptogenesis

Neutrino Baryon Masses Asymmetry

Why are so light?

Seesaw Model Simplest extension of SM able to account for neutrino masses. Consists in the addition of heavy fermion singlets ( ) to the SM field content:

New Scale

Minkowski 77; Gell-Mann, Ramond, Slansky 79 Yanagida 79; Mohapatra, Senjanovic 80. Seesaw Model Simplest extension of SM able to account for neutrino masses. Consists in the addition of heavy fermion singlets ( ) to the SM field content:

Seesaw Model Simplest extension of SM able to account for neutrino masses. Consists in the addition of heavy fermion singlets ( ) to the SM field content:

Interaction with SM particles via Yukawa coupling

Seesaw Model Simplest extension of SM able to account for neutrino masses. Consists in the addition of heavy fermion singlets ( ) to the SM field content:

Majorana mass Interaction with SM particles term via Yukawa coupling

Lepton Number Violation

Standard Leptogenesis Right-handed neutrino decays which violate CP and lepton number generate lepton asymmetry before

Lepton Baryon Sphalerons Asymmetry Asymmetry L 0 B-L=0 B 0

Temperature

Time Sakharov conditions

Baryon number violation 1 If baryon asymmetry is conserved, no baryon number can be generated

OK in Sphalerons the SM @T 140Gev

Sakharov conditions

C and CP violation 2 There is CP violation Not enough CP violation in the SM quark sector in SM !!

if it enough also exists CP violation in lepton sector

Sakharov conditions

C and CP violation 2

At one loop: CP asymmetry generated via interference effects

Dependence on leptonic CP phases

● It is encoded in the Yukawa couplings:

● Generation of light neutrino masses imposes constraints on Yukawa couplings from neutrino oscillation data

Dependence on leptonic CP phases

● It is encoded in the Yukawa couplings:

Casas-Ibarra

Light Sector Heavy Sector

● Majorana phases ● Complex orthogonal matrix (experimentally challenging) # of extra CP phases ● Dirac CP phase 3 (accessible via neutrino oscillations) 1

Sakharov conditions

Departure from thermal equilibrium 3

out of abundance decoupling equilibrium decay before TEW

x

equilibrium distribution

Testable Leptogenesis

Neutrino Baryon Masses Asymmetry

Testability

The New Physics Scale

Vanilla Leptogenesis meV eV keV MeV GeV TeV not testable GUTs The New Physics Scale

Vanilla

Cosmology Leptogenesis

meV eV keV MeV GeV TeV not testable GUTs

P. Hernandez, M. Kekic, JLP 1311.2614;1406.2961 The New Physics Scale

Vanilla

Cosmology Leptogenesis

meV eV keV MeV GeV TeV not testable GUTs

● decay ● Leptogenesis ● Resonant LFV, SHiP, LHC via Oscillations Leptogenesis FCC. M=0.1-100GeV M>100GeV Akhmedov, Rubakov, Smirnov (ARS) Pilaftsis Asaka, Shaposnikov (AS) The New Physics Scale

Vanilla

Cosmology Leptogenesis

meV eV keV MeV GeV TeV not testable GUTs

● decay ● Leptogenesis ● Resonant LFV, SHiP, LHC via Oscillations Leptogenesis FCC. M=0.1-100GeV M>100GeV Akhmedov, Rubakov, Smirnov (ARS) Pilaftsis Asaka, Shaposnikov (AS) Low Scale Leptogenesis (ARS)

abundance CP asymmetry generated through NR oscillations deviation from equilibrium before TEW

equilibrium distribution

sphalerons

Kinematic Equations

We have computed the equations for the density matrix in the Raffelt- Sigl formalism

● Fermi-Dirac or Bose-Einstein statistics is kept throughout

● Collision terms include 2 ↔ 2 scatterings at tree level with top quarks and gauge bosons, as well as 1 ↔ 2 scatterings, including the resummation of scatterings mediated by soft gauge bosons

● Leptonic chemical potentials are kept in all collision terms to linear order

● Include spectator processes Solved using SQuIDS Arguelles Delgado, Salvado, Weaver 2015 https://github.com/jsalvado/SQuIDS Full parameter space exploration NR=2

Bayesian posterior probabilities (using nested sampling Montecarlo MultiNest)

Casas-Ibarra

Parameters of the model

Fixed by neutrino Free oscillation experiments parameters Leptogenesis in Minimal Model NR=2 Non very degenerate solutions

PRESENT BOUND

FUTURE SENSITIVITY

Inverted light neutrino ordering (IH)

Hernandez, Kekic, JLP, Racker, Salvado 2016 arXiv:1606.06719 Leptogenesis in Minimal Model NR=2 Non very degenerate solutions

PRESENT BOUND

FUTURE SENSITIVITY

Inverted light neutrino ordering (IH)

Hernandez, Kekic, JLP, Racker, Salvado 2016 arXiv:1606.06719 Leptogenesis in Minimal Model NR=2 Non very degenerate solutions

PRESENT BOUND

FUTURE SENSITIVITY

Inverted light neutrino ordering (IH)

Hernandez, Kekic, JLP, Racker, Salvado 2016 arXiv:1606.06719 Leptogenesis in Minimal Model NR=2 SHiP

DUNE

Inverted light neutrino ordering

Hernandez, Kekic, JLP, Racker, Salvado 2016 arXiv:1606.06719 Can we experimentally determine Baryon asymmetry generated in minimal model ?

Predicting YB in minimal model NR=2

● Baryon asymmetry depends on all the unknown parameters

● SHiP sensitivity

Hernandez, Kekic, JLP, Racker, Salvado 2016 Predicting YB in minimal model NR=2

● Baryon asymmetry depends on all the unknown parameters

● SHiP sensitivity

SHiP sensitive to

Hernandez, Kekic, JLP, Racker, Salvado 2016 Predicting YB in minimal model NR=2

● Baryon asymmetry depends on all the unknown parameters

● SHiP sensitivity

SHiP sensitive to

Neutrinoless double beta decay sensitive to through interference between light and heavy contribution

Hernandez, Kekic, JLP, Racker, Salvado 2016 Predicting YB in minimal model NR=2

SHiP

SHiP+

Observed Baryon

asymmetry Hernandez, Kekic, JLP, Racker, Salvado 1606.06719 Predicting YB in minimal model NR=2

SHiP

SHiP+

Observed Baryon

asymmetry Hernandez, Kekic, JLP, Racker, Salvado 1606.06719 Predicting YB in minimal model NR=2

SHiP

SHiP+

Observed Baryon

asymmetry Hernandez, Kekic, JLP, Racker, Salvado 1606.06719 Testability of neutrino mass generation mechanism

Caputo, Hernandez, JLP, Salvado arXiv:1704.08721

Minimal Model: Flavor Structure

NOT ALLOWED

NOT ALLOWED

Caputo, Hernandez, JLP, Salvado arXiv:1704.08721 CP-violation in minimal model

● SHiP and FCC-ee can measure:

Sensitivity to PMNS CP-phases!

●

●

CP-violation in minimal model

SHiP

FCC-ee

5 discovery CP-violation

Caputo, Hernandez, Kekic, JLP, Salvado arXiv:1611.05000 To what extent can all this be modified in the presence of additional New Physics?

Caputo, Hernandez, JLP, Salvado arXiv:1704.08721

Model Independent Approach: EFT

● The leading NP effects are encoded in effective d=5 operators that can be constructed in a gauge invariant way with the SM fields and the Nj

Graesser 2007; del Aguila, Bar-Shalom, Soni, Wudka 2009; Aparici, Kim, Santamaria, Wudka 2009. Model Independent Approach: EFT

● The leading NP effects are encoded in effective d=5 operators that can be constructed in a gauge invariant way with the SM fields and the Nj

- Modification of flavor structure controlled by the lightest neutrino mass generated by Weinberg . Predictions kept if

Model Independent Approach: EFT

● The leading NP effects are encoded in effective d=5 operators that can be constructed in a gauge invariant way with the SM fields and the Nj

- The higgs can decay to a pair of long-lived heavy neutrinos! (powerful signal of two displaced vertices)

Accomando, Delle Rose, Moretti, Olaiya, Shepherd-Themistocleous 2017 Caputo, Hernandez, JLP, Salvado 2017

Seesaw Portal

● Higgs can decay to a pair of long-lived heavy neutrinos. Powerful signal of two displaced vertices.

LHC bound:

Conclusions

● Low Scale Minimal seesaw models are testable and highly predictive

● Successful is possible with a mild heavy neutrino degeneracy, small NR masses M~O(GeV), and significant NR contributions to neutrinoless double beta decay.

● If O(GeV) heavy neutrinos would be discovered in SHiP and the neutrino ordering is inverted, predicting the baryon asymmetry looks in principle viable.

● Extremely constrained flavor structure which shows a strong correlation with the PMNS CP-phases.

● New window to determine PMNS CP violating phases (both the Dirac and Majorana phases).

● Precise measurement of flavor ratios will be essential in establishing the connection between the observed heavy states and neutrino masses.

Thanks!

Approximated LNC

Mohapatra, Valle 1986; Bernabeu, Santamaria, Vidal, Mendez, Valle 1987; Malinsky, Romao, Valle 2005...

● Light nu masses suppressed with LNV parameters

● Quasi-Dirac heavy neutrinos:

Approximated LNC

Contours of constant ratio Minimal Model

NH

IH

Minimal Model + NP

Seesaw Portal

i) Search of displaced tracks in the inner tracker where at least one displace lepton, e or μ, is reconstructed from each vertex. ii) Search for displaced tracks in the muon chambers and outside the inner tracker, where at least one μ is reconstructed from each vertex. Accomando, Delle Rose, Moretti, Olaiya, Shepherd-Themistocleous 2017 CMS Collaboration 1411.6977, CMS-PAS-EXO-14-012 Seesaw Portal Inner Tracker (NH) Muon Chamber (NH)

Mathusla (14 TeV, 3000 fb-1) Chou, Curtin, Lubatti 2017

IH

-1 LHC (13 TeV, 300 fb ) Seesaw Portal

NH

IH

-1 LHC (13 TeV, 300 fb ) Model Independent Approach: EFT

● The leading NP effects are encoded in effective d=5 operators that can be constructed in a gauge invariant way with the SM fields and the Nj

- Electroweak moment Nj couplings.

- Generated only at the 1-loop level (suppression with respect to other operators expected)

Aparici, Kim, Santamaria, Wudka 2009.

1-loop contribution of to nu masses

Production Cross Section

Production Branching Ratio

Kinematical Cuts

(Independent of U)

Cuts associated to displaced tracks

Cuts associated to displaced tracks

5 discovery CP-violation

SHiP: M= 1 GeV FCC: M= 30 GeV

Kinematic Equations We have computed and solved the equations for the density matrix in the Raffelt-Sigl formalism using the code SQuIDS Arguelles Delgado, Salvado, Weaver 2015 https://github.com/jsalvado/SQuIDS Predicting YB in minimal model NR=2

● Neutrinoless double beta decay effective mass in the IH case

LIGHT NEUTRINO contribution

HEAVY NEUTRINO contribution

● Heavy neutrino contribution can be sizable for Mitra, Senjanovic, Vissani 2011 JLP, Pascoli, Wong 2012 SHIP sensitive to PMNS CP phases

analytical expectation

SHIP measurement

Recall, neutrino oscillation experiments sensitive to

Leptogenesis in Minimal Model

Hernandez, Kekic, JLP, Racker, Salvado 2016 ArXiv:1606.06719 ? Dirac vs Majorana: decay

● Outstanding complementarity EXCLUDED with n-oscillations, Katrin and cosmology.

IO ● Extremely relevant input in order to probe New Physics models responsible for nu mass generation.

NO Planck + BAO

Sum of three neutrino masses

Capozzi, Di Valentino, Lisi, Marrone, Melchiorri, Palazzo 1703.0447 ? Dirac vs Majorana

● Outstanding complementarity PRESENT BOUND with 0nbb decay and cosmology.

0nbb ● Extremely relevant input in prospects IO order to probe New Physics models responsible for nu mass generation.

NO Planck + BAO

Capozzi, Di Valentino, Lisi, Marrone, Melchiorri, Palazzo 1703.0447 Heavy New Physics scale

● suggests M close to the GUT scale.

● Drawback: New Physics effects at low energies very suppressed by the NP scale M.

Light New Physics scale

● Contrary to the high scale models, a low Majorana scale does not worsen the Higgs mass hierarchy problem.

Vissani 1998

● Drawback: In principle, a small M requires . Suppression of the NP effects controlled by the Yukawa couplings.

Sizable Phenomenology?

● Sizable New Physics effects require:

(1)

(2) Too large neutrino masses!!

● Way out. Neutrino mass suppression coming from symmetry. Approximate L conservation.

Inverse and direct seesaw models. Mohapatra 1986; Mohapatra, Valle 1986; Bernabeu, Santamaria, Vidal, Mendez, Valle 1987; Branco, Grimus, Lavoura 1989; Malinksy, Romao, Valle 2005; Kersten, Smirnov 2007; Gavela, Hambye, D. Hernandez, P. Hernandez 2009;