Marco Drewes, Université catholique de Louvain. The Other Neutrinos IAP Meeting. Université libre de Bruxelles

Marco Drewes, Université catholique de Louvain The Other Neutrinos 21.12.2017 IAP Meeting Université libre de Bruxelles

The Standard Model of Particle 125 GeV The periodic table of elementary particles

The Standard Model of Particle Are we missing a type of neutrinos? 125 GeV The periodic table of elementary particles

The Standard Model of Particle Are we missing a type of neutrinos? If yes, what is their mass? And what would their existence imply? 125 GeV The periodic table of elementary particles

How Heavy are the Missing Neutrinos? ev kev MeV GeV TeV 10 14 GeV Traditionally: assume large mass for theoretical reasons ( naturalness, grand unification)

How Heavy are the Missing Neutrinos? ev kev MeV GeV TeV 10 14 GeV Traditionally: assume large mass for theoretical reasons ( naturalness, grand unification) experimentally inaccessible

How Heavy are the Missing Neutrinos? ev kev MeV GeV TeV 10 14 GeV experimentally accessible masses Understand the implications across the entire experimentally accessible mass range

Heavy Neutrinos Could Solve Key Problems What is the origin of neutrino mass? Possible key to embed Standard Model in a more fundamental theory of Nature Why was there more matter than antimatter in the early universe? so that some matter survived the mutual annihilation to form galaxies, stars etc. What is the Dark Matter made of? It makes up most of the mass in the universe.

Heavy Neutrinos Could Solve Key Problems What is the origin of neutrino mass? Possible key to embed Standard Model in a more fundamental theory of Nature L = L SM + i R 6@ R LL F R H H R F L Why was there more matter than antimatter in the early universe? so that some matter survived the mutual annihilation to form galaxies, stars etc. What is the Dark Matter made of? It makes up most of the mass in the universe. 1 2 ( c RM M R + R M M c R) three light neutrinos mostly active SU(2) doublet ' U ( L + R c ) with masses m ' M M T = v 2 FM 1 three heavy mostly singlet neutrinos N ' R + T L c with masses M N ' M M M F T Minkowski 79, Gell-Mann/Ramond/ Slansky 79, Mohapatra/Senjanovic 79, Yanagida 80, Schechter/Valle 80

Heavy Neutrinos Could Solve Key Problems What is the origin of neutrino mass? Possible key to embed Standard Model in a more fundamental theory of Nature Why was there more matter than antimatter in the early universe? Leptogenesis so that some matter survived the mutual annihilation to form galaxies, stars etc. Heavy neutrinos are unstable particles What is the Dark Matter made of? Can decay into matter or antimatter Quantum effects can make decay into matter more likely It makes up most of the mass in the universe. Nonequilibrium quantum process produces matter excess

Heavy Neutrinos Could Solve Key Problems What is the origin of neutrino mass? Possible key to embed Standard Model in a more fundamental theory of Nature Why was there more matter than antimatter in the early universe? so that some matter survived the mutual annihilation to form galaxies, stars etc. Not today s topic. Recent review: 1602.04816 What is the Dark Matter made of? It makes up most of the mass in the universe.

Right Handed Neutrinos and the Light Neutrino Masses ev kev MeV GeV TeV 10 14 GeV Neutrino LSND etc Explain Light Neutrino Masses ( Seesaw Mechanism ) Cosmology Dark Radiation Dark Matter Origin of Matter ( Leptogenesis ) High Energy

Heavy Neutrinos as the Origin of Matter ev kev MeV GeV TeV 10 14 GeV Neutrino Cosmology Origin of Matter ( Leptogenesis ) High Energy

Heavy Neutrinos as the Origin of Matter ev kev MeV GeV TeV 10 14 GeV Leptogenesis in heavy neutrino decay Neutrino Cosmology Origin of Matter ( Leptogenesis ) High Energy

Heavy Neutrinos as the Origin of Matter Leptogenesis from heavy neutrino oscillations baryon charge lepton charge source term Neutrino Cosmology High Energy ev kev MeV EW scale / temperature GeV TeV 10 14 GeV Leptogenesis in heavy neutrino decay Origin of Matter ( Leptogenesis )

Heavy Neutrinos and the Light Neutrino Masses ev kev MeV GeV TeV 10 14 GeV Neutrino Explain Light Neutrino Masses ( Seesaw Mechanism ) Cosmology Origin of Matter ( Leptogenesis ) High Energy

Heavy Neutrinos and the Light Neutrino Masses ev kev MeV GeV TeV 10 14 GeV Neutrino Explain Light Neutrino Masses ( Seesaw Mechanism ) Cosmology Dark Matter Origin of Matter ( Leptogenesis ) neutrino oscillation data High Energy

How to Find Heavy Neutrinos? ev kev MeV GeV TeV 10 14 GeV Neutrino Explain Light Neutrino Masses ( Seesaw Mechanism ) Cosmology Origin of Matter ( Leptogenesis ) High Energy

How to Find Heavy Neutrinos? ev kev MeV GeV TeV 10 14 GeV Neutrino Explain Light Neutrino Masses ( Seesaw Mechanism ) Cosmology Origin of Matter ( Leptogenesis ) High Energy Direct Searches

How to Find Heavy Neutrinos? ev nuclear decay spectra kev fixed target experiments MeV GeV b factories TeV proton 10 colliders 14 GeV Neutrino Oscillation Anomalies Explain light Neutrino Masses ( Seesaw Mechanism ) electron colliders Cosmology TRISTAN, ECHO Origin of Matter ( Leptogenesis ) High Energy Direct Searches

How to Find Heavy Neutrinos? ev kev MeV GeV TeV 10 14 GeV Neutrino Explain light Neutrino Masses ( Seesaw Mechanism ) Cosmology Origin of Matter ( Leptogenesis ) High Energy Direct Searches Indirect Searches

How to Find Heavy Neutrinos? Neutrino ev Oscillation Anomalies kev MeV GeV TeV 10 14 GeV rare processes, precision tests, Explain light Neutrino Masses neutrinoless double β decay ( Seesaw Mechanism ) lepton universality Cosmology High Energy Dark Radiation Dark Matter lepton number violating decays CMK unitarity electroweak precision data Indirect Searches Origin of Matter ( Leptogenesis )

( ) Experimental Perspectives - ( ) - ( ) - ( ) - / μ - - [ ] plot from MaD/Garbrecht/Gueter/Klaric 1609.09069

Priors and Assumptions - ( ) - ( ) - ( ) - / - ( ) - [ ] MaD/Garbrecht/Gueter/Klaric 16b Hernandez/Kekic/Lopez-Pavon/Racker/Savaldo 16

What is the allowed range of heavy neutrino mass and mixing for leptogenesis? What is the most likely place where leptogenesis will occur, given some bottom-up prior? - - ( ) - ( ) ( ) - / - - ( ) [ ] Shaposhnikov 08 Hernandez/Kekic/Lopez-Pavon/Racker/Rius 15 Canetti/Shaposhnikov 10 Hernandez/Kekic/Lopez-Pavon/Racker/Savaldo 16 Canetti/MaD/Shaposhnikov 13 Canetti/MaD/Frossard/Shaposhnikov 13 MaD/Eijima 16 MaD/Garbrecht/Gueter/Klaric 16a MaD/Garbrecht/Gueter/Klaric 16b Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric 17 Abada/Arcadi/Domcke/Lucente 17

Experimental Perspectives ATLAS/CMS (Izaguirre/Shuve) Hard to reach leptogenesis region How about - MATHUSLA? ( ) - ( ) - ( ) - / μ - - Displaced vertex searches at LHCb Antusch/Cazzato/Fischer ( ) [ ] plot from MaD/Garbrecht/Gueter/Klaric 1609.09069

Experimental Perspectives - - ( ) - ( ) ( ) - / μ - NA62 dump mode - SHiP see 1504.04855 1504 ( ) [ ] plot from MaD/Garbrecht/Gueter/Klaric 1609.09069

Experimental Perspectives - - ( ) - ( ) ( ) - / μ - - NA62 dump mode Can also modify prediction for neutrinoless double β decay MaD/Eijima 16. Hernandez/Kekic/Lopez-Pavon/Racker/Savaldo 16, SHiP see 1504.04855 Asaka/Eijima/Ishida 16 1504 [ ] ( ) plot from MaD/Garbrecht/Gueter/Klaric 1609.09069

Neutrino Mixing vs Collider Searches M = 1 GeV 0.8 U 2 coupling to muon U 2 /U 2 0.6 0.4 0.2 9. 10-7 8. 10-7 7. 10-7 6. 10-7 5. 10-7 4. 10-7 3. 10-7 2. 10-7 0.0 0.00 0.02 0.04 0.06 0.08 0.10 0.12 U 2 e /U coupling to 2 electron plot from MaD/Garbrecht/Gueter/Klaric 1609.09069

Neutrino Mixing vs Collider Searches M = 1 GeV 0.8 Shades: U 2 coupling to muon U 2 /U 2 0.6 0.4 0.2 How testable 9. 10 is leptogenesis? -7 8. 10-7 7. 10 [darker = larger -7 total mixing] 6. 10-7 5. 10-7 4. 10-7 3. 10-7 2. 10-7 0.0 0.00 0.02 0.04 0.06 0.08 0.10 0.12 U 2 e /U coupling to 2 electron plot from MaD/Garbrecht/Gueter/Klaric 1609.09069

Neutrino Mixing vs Collider Searches M = 1 GeV 0.8 Area U 2 within black line: coupling to muon U 2 /U 2 0.6 0.4 0.2 9. 10-7 allowed by neutrino 8. 10-7 oscillation 7. 10 data -7 6. 10-7 5. 10 coupling -7 to electron 4. 10 maximal -7 12%! 3. 10-7 [for 2. 10 normal neutrino -7 mass ordering] 0.0 0.00 0.02 0.04 0.06 0.08 0.10 0.12 U 2 e /U coupling to 2 electron plot from MaD/Garbrecht/Gueter/Klaric 1609.09069

Neutrino Mixing vs Collider Searches 0.8 M = 1 GeV Effect on production at lepton colliders: e + ν Area U 2 within black line: coupling to muon flavour U 2 /U 2 0.6 0.4 0.2 e W suppressed compared to e + Z θ e N any θ a ν 9. 10-7 allowed by neutrino 8. 10-7 oscillation 7. 10 data -7 6. 10-7 5. 10 coupling -7 to electron 4. 10 maximal -7 12%! 3. 10-7 [for 2. 10 normal neutrino -7 mass ordering] 0.0 0.00 0.02 0.04 0.06 0.08 0.10 0.12 e U 2 e /U coupling to electron 2 flavour N plot from MaD/Garbrecht/Gueter/Klaric 1609.09069

Displaced Vertices at FCC-ee normal ordering inverted ordering 10-5 disfavoured by DELPHI 10-5 BAU (upper bound) disfavoured by DELPHI 10-7 BAU (upper bound) 10-7 U 2 U 2 10-9 FCC-ee @ s =90 GeV 10-9 FCC-ee @ s =90 GeV 10-11 10-11 constrained by neutrino oscillation data constrained by neutrino oscillation data 5 10 20 50 M [GeV] 5 10 20 50 M [GeV] Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric 1710.03744

Displaced Vertices at CEPC normal ordering inverted ordering 10-5 disfavoured by DELPHI 10-5 BAU (upper bound) disfavoured by DELPHI 10-7 BAU (upper bound) 0.1 ab -1 10-7 0.1 ab -1 U 2 10-9 10 ab -1 1 ab -1 U 2 10-9 10 ab -1 1 ab -1 10-11 constrained by neutrino oscillation data 10-11 constrained by neutrino oscillation data 5 10 20 50 M [GeV] 5 10 20 50 M [GeV] Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric 1710.03744

Displaced Vertices at ILC normal ordering inverted ordering 10-5 disfavoured by DELPHI 10-5 BAU (upper bound) disfavoured by DELPHI 10-7 BAU (upper bound) 10-7 U 2 ILC @ s =90 GeV U 2 ILC @ s =90 GeV 10-9 10-9 ILC @ s =500 GeV 10-11 constrained by neutrino oscillation data 10-11 constrained by neutrino oscillation data 5 10 20 50 M [GeV] 5 10 20 50 M [GeV] Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric 1710.03744

Leptogenesis and Heavy Neutrino Mass Splitting normal ordering inverted ordering 10-7 10-7 10-8 M 10-8 M 10-9 10-9 U 2 10-10 U 2 10-10 10-11 10-11 10-12 seesaw limit 10-12 seesaw limit 10-20 10-15 10-10 10-5 10 0 M[GeV] 10-20 10-15 10-10 10-5 10 0 M[GeV] Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric 1710.03744

Leptogenesis and Heavy Neutrino Mass Splitting 10-7 RHN oscillations in detector normal ordering LNV vs LFV events 10-7 direct kinematic measurement inverted ordering 10-8 M 10-8 M 10-9 10-9 U 2 10-10 U 2 10-10 10-11 10-11 10-12 seesaw limit 10-12 seesaw limit 10-20 10-15 10-10 10-5 10 0 M[GeV] 10-20 10-15 10-10 10-5 10 0 M[GeV] Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric 1710.03744

Leptogenesis and Heavy Neutrino Mass Splitting normal ordering inverted ordering 10-7 10-7 10-8 M 10-8 M 10-9 10-9 U 2 10-10 U 2 10-10 10-11 10-11 10-12 seesaw limit 10-12 seesaw limit 10-20 10-15 10-10 10-5 10 0 M[GeV] with three RH neutrinos: 10-20 10-15 10-10 10-5 10 0 M[GeV] no need Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric for mass degeneracy for leptogenesis MaD/Garbrecht 1710.0374412

Conclusions Heavy neutrinos can explain the origin of neutrino masses and matter in the universe Collider data + DUNE or NOvA can fully test the minimal seesaw model in the sub-tev mass range non-collider data can help to guide collider searches (e.g. flavour structure, LNV vs LFV) several colliders can probably reach the leptogenesis region : ILC, CEPC, FCC-ee Fully testable model of neutrino masses and baryogengesis

MATHUSLA MAssive Timing Hodoscope for Ultra-Stable NeutraL PArticles charged particles displaced vertex from LLP decay is so spectacular DV LLP Surface Scintillator surrounds detector DV Air Multi-layer tracker in the roof 20m 100m ATLAS or CMS SIGNAL: neutral LLP LHC beam pipe 100m 200m slide by David Curtin

Number of Events normal ordering 10-4 inverted ordering 50 000 disfavoured by DELPHI 10-5 10 000 10-6 10-5 2000 BAU 10 (uppe r bou -8 nd) 500 U2 U2 disfavoured by DELPHI 50 000 10-6 10-7 10 200 000 10-4 10-9 BAU 10 000 (uppe r bou -7 nd) 2000 10-8 10-9 500 100 10-10 10-10 10-11 20 constrained b y neutrino osc 10-12 illation data 100 10-11 constrained b y neutrino osc 10-12 illation data 20 5 10-13 5 10 20 M [GeV] 30 40 50 10 5-13 5 10 20 30 40 50 M [GeV] Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric 1710.03744

Number of Events normal ordering 10-4 inverted ordering 50 000 disfavoured by DELPHI 10-5 10 000 10-6 10-5 2000 BAU 10 (uppe r bou -8 nd) 500 U2 U2 disfavoured by DELPHI 50 000 10-6 10-7 10 200 000 10-4 10-9 BAU 10 000 (uppe r bou -7 nd) 2000 10-8 10-9 500 100 10-10 10-10 10-11 20 constrained b y neutrino osc 10-12 illation data 100 10-11 constrained b y neutrino osc 10-12 illation data 20 5 10-13 5 10 20 M [GeV] 30 40 50 10 5-13 5 10 20 30 40 50 M [GeV] percent level measurement of flavour structure! Antusch/Cazzato/MaD/Fischer/Garbrecht/Gueter/Klaric 1710.03744

Right Handed Neutrinos and the Light Neutrino Masses ev kev MeV GeV TeV 10 14 GeV Neutrino LSND etc Explain Light Neutrino Masses ( Seesaw Mechanism ) Cosmology Dark Radiation Dark Matter Origin of Matter ( Leptogenesis ) High Energy Disfavoured by CMB and BBN

Right Handed Neutrinos and the Light Neutrino Masses Neutrino LSND etc Cosmology Dark Radiation ev kev MeV GeV TeV 1014 GeV RH neutrinos must mix to generate light neutrino mass Explain Light Neutrino Masses ( Seesaw Mechanism ) Mixing leads to production in the early universe Dark Origin of Matter Matter ( Leptogenesis ) For masses below 100 MeV, High Energy RH neutrinos do not decay before BBN Disfavoured by CMB and BBN Their decay either disturbs BBN or affects the CMB

Right Handed Neutrinos and the Light Neutrino Masses Cosmology Dark Radiation Neutrino LSND etc ev MeV kev 1014 GeV TeV GeV Seesaw: Need one RHN for Explain Light Neutrino each mmasses i 0 ( Seesaw Mechanism ) For mlightest > 10-3 ev, three RHN reach equilibrium Dark Matter Log10 @Mi HeVLD Origin of Matter 10 ( Leptogenesis ) 8 6 High Energy 4 Disfavoured by CMB and BBN 2 0 1 2 3 Hernandez/Kekic/Lopez-Pavon 1406.2961

Right Handed Neutrinos and the Light Neutrino Masses Cosmology Dark Radiation Neutrino LSND etc ev MeV kev 1014 GeV TeV GeV Seesaw: Need one RHN for Explain Light Neutrino each mmasses i 0 ( Seesaw Mechanism ) For mlightest < 10-3 ev, one RHN almost decouples Dark Matter Log10 @Mi HeVLD Origin of Matter 10 ( Leptogenesis ) 8 6 High Energy 4 Disfavoured by CMB and BBN 2 0 1 2 3 Hernandez/Kekic/Lopez-Pavon 1406.2961

Right Handed Neutrinos and the Light Neutrino Masses Cosmology Dark Radiation Neutrino LSND etc ev MeV kev 1014 GeV TeV GeV Seesaw: Need one RHN for Explain Light Neutrino each mmasses i 0 ( Seesaw Mechanism ) For mlightest < 10-3 ev, one RHN almost decouples Dark Matter Log10 @Mi HeVLD Origin of Matter 10 ( Leptogenesis ) 8 Two do Seesaw, and leptogenesis 6 High Energy 4 Disfavoured by CMB and BBN DM candidate 2 Asaka/Shaposhnikov 2005 0 1 2 3 Hernandez/Kekic/Lopez-Pavon 1406.2961

Neutrino masses vs collider searches neutrino masses mi are small (sub ev) active-sterile mixing angle θ must be small Problem! colliders rely on branching ratio active-sterile mixing angle θ must be large

Neutrino masses vs collider searches neutrino masses mi are small (sub ev) active-sterile mixing angle θ must be small approximate Problem! Solution B-L conservation e.g. Kersten/Smirnov 07 colliders rely on branching ratio active-sterile mixing angle θ must be large

Neutrino masses vs collider searches Large branching rations consistent with small neutrino masses approximate B-L conservation meets neutrinoless double ß decay constraints implies Heavy Neutrino mass degeneracy e.g. Kersten/Smirnov 07! suppresses LNV collider signatures!

Neutrino masses vs collider searches hard to distinguish signatures kinematically cannot study heavy flavours individually may observe CP violation in Heavy Neutrino decay Cvetic/Kim/Saa 14 connection to leptogenesis? golden channels suppressed need to use other channels (LFV, displaced vertices) implies! Heavy Neutrino mass degeneracy suppresses LNV collider signatures!