Landscape of BSM Physics@ Neutrino Experiments
Sanjib Kumar Agarwalla
sanjib@iopb.res.in
https://twitter.com/sanjibneutrino

Institute of Physics (IOP), Bhubaneswar, India

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

4.5%

2.3%

3%

1.1%

6%

16%

Tremendous boost to search for BSM physics at ! expts

Robust three-flavor neutrino oscillation paradigm

Remarkable Precision on Neutrino Oscillation Parameters

Agarwalla, Kundu, Prakash, Singh, in preparation
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Very Bright Future Ahead: Triumph of JUNO
0.307±0.002 0.7%

NuFIT 5.0

0.304±0.012 3.9%

KamLAND+SK+SNO

0.306+0.013°0.012 4.1%

SuperK+SNO

0.306±0.014 4.6%
0.299+0.016°0.015 5.2%

SNO
Forero et al.

0.318±0.016 5.0%

JUNO T+SNO(NC)(expected)

0.316+0.034°0.026 9.5%

KamLAND
0.28

0.30

0.32
sin2 µ120.307±0.023 7.5%

0.34

2.442+0.026°0.028 1.1%

Forero et al.
v2.0b 2021.07: git.jinr.ru/nu/osc

JUNO j (expected)

2.388±0.011 0.5%

NuFIT 5.0
Daya Bay
T2K
MINOS+

2.49 +0.06
°0.08

2.8%

2.40

SuperK
nGd

2.31 +0.11
°0.13

nH

0.36

+0.08
°0.09
+0.11
°0.12

2.40
2.69 ±0.12

IceCubeRENO

1.4%

2.471+0.068°0.070 2.8%
2.41 ±0.07 2.9%

nGd

NOvA

RENO

2.48 +0.03
°0.04

2.2

2.4
2.6
|¢m232 |, 10°3 eV2

2.8

2.48 +0.28
°0.32

3.5%
4.8%
4.5%
5.2%
12.1%

JUNO j (expect)

KamLAND+SK+SNO

7.51 +0.19°0.18

2.492±0.011 0.4%

NuFIT 5.0

2.498±0.028 1.1%

Forero et al.

2.54 ±0.03

1.2%

NOvA

2.45 ±0.06

2.4%

KamLAND

7.54

NuFIT 5.0

7.42

Forero et al.

7.50

SuperK+SNO

6.11

JUNO T+SNO(NC) (expected)

7.5

SNO

5.60
5

6
7
¢m221 , 10°5 eV2

8

9

+0.19
°0.18
+0.21
°0.20
+0.22
°0.20
+1.21
°0.68
+1.6
°1.2
+1.90
°1.40

2.5%
2.5%
2.8%
2.8%
15.5%
18.7%
29.5%

v2.0b 2021.07: git.jinr.ru/nu/osc7.540±0.044 0.6%

Daya Bay2.575+0.068°0.070 2.7%

nGd

2.45 +0.07°0.08

MINOS+
RENO

nGd

2.79 ±0.12

IceCube2.32

SuperK

2.40

RENO

nH

2.58
2.2

2.4
2.6
|¢m232 |, 10°3 eV2

2.8

+0.11
°0.13
+0.09
°0.32
+0.28
°0.32

3.1%
4.3%
5.2%
8.5%

v5.0b 2021.07: git.jinr.ru/nu/osc

Inverted mass ordering

JUNO j (expected)

4v5.0b 2021.07: git.jinr.ru/nu/osc

Normal mass ordering
JUNO j (expect)

11.6%

Maxim Gonchar (JUNO Collaboration) EPS-HEP 2021, July 26

JUNO will improve significantly our knowledge on neutrino oscillation parameters. Thesedevelopments are very crucial to probe sub-leading BSM effects at next generation long-baseline
and atmospheric experiments, IceCube-Upgrade, IceCube-Gen2
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Probing BSM Scenarios Across I8 orders in E and 25 orders in L
Non-zero neutrino mass: first experimental proof (gateway) for BSM physics
Several BSM possibilities can be introduced in the framework of Effective Field Theory (EFT)
d=5 Weinberg Operator: LLHH, Λ: New Physics Scale
S. Weinberg, PRL 43 (1979) 1566
BSM Scenarios naturally arise due to different mechanisms for generating ! masses (e.g. seesaw)

Many models of BSM physics suggest: new fundamental particles and interactions,
new sources of CP-invariance violation, lepton number and lepton flavor violations

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

3/29

Probing BSM Scenarios Across I8 orders in E and 25 orders in L
Non-zero neutrino mass: first experimental proof (gateway) for BSM physics
Several BSM possibilities can be introduced in the framework of Effective Field Theory (EFT)
d=5 Weinberg Operator: LLHH, Λ: New Physics Scale
S. Weinberg, PRL 43 (1979) 1566
BSM Scenarios naturally arise due to different mechanisms for generating ! masses (e.g. seesaw)

Many models of BSM physics suggest: new fundamental particles and interactions,
new sources of CP-invariance violation, lepton number and lepton flavor violations
Probe BSM Physics at High Energies (TeV-PeV)
High-Energy (TeV-PeV) Astrophysical Neutrinos
coming from cosmic distances (Mpc-Gpc)
Giant Neutrino Telescopes: IceCube@South Pole,KM3NeT@Mediterranean Sea, future IceCube-Gen2
Novel Approach -New Physics beyond the reach of modern Colliders
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

4/29

Probing BSM Scenarios Across I8 orders in E and 25 orders in L
Non-zero neutrino mass: first experimental proof (gateway) for BSM physics
Several BSM possibilities can be introduced in the framework of Effective Field Theory (EFT)
d=5 Weinberg Operator: LLHH, Λ: New Physics Scale
S. Weinberg, PRL 43 (1979) 1566
BSM Scenarios naturally arise due to different mechanisms for generating ! masses (e.g. seesaw)

Many models of BSM physics suggest: new fundamental particles and interactions,
new sources of CP-invariance violation, lepton number and lepton flavor violations
Probe BSM Physics at High Energies (TeV-PeV)
High-Energy (TeV-PeV) Astrophysical Neutrinos
coming from cosmic distances (Mpc-Gpc)
Giant Neutrino Telescopes: IceCube@South Pole,KM3NeT@Mediterranean Sea, future IceCube-Gen2
Novel Approach -New Physics beyond the reach of modern Colliders

Probe BSM Physics at Low Energies (MeV-GeV)
Low-Energy (MeV-GeV) Accelerator & Atmospheric!s travelling terrestrial distances (few m - 1000s of km)
Accelerator: DUNE@USA, T2HK@Japan
Atmospheric: India-based Neutrino Observatory (INO)
Expected to measure oscillation parameters with a
precision around a few % -- sensitive to sub-leading
BSM physics at low energies
Complement BSM search @ High-Energy Colliders

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Landscape of BSM Scenarios affecting Neutrino Experiments

Courtesy Mauricio Bustamante

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Landscape of BSM Scenarios affecting Neutrino Experiments

Alters neutrino flux

Agarwalla et al., JHEP 05 (2012) 154

Courtesy Mauricio Bustamante

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Landscape of BSM Scenarios affecting Neutrino Experiments
Alters neutrino flux, oscillation, mixing
L = 295 km

Alters neutrino flux

Agarwalla et al., JHEP 02 (2016) 111

Agarwalla et al., JHEP 05 (2012) 154

Courtesy Mauricio Bustamante

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Landscape of BSM Scenarios affecting Neutrino Experiments
Alters neutrino flux, oscillation, mixing
L = 295 km

Alters neutrino flux

Agarwalla et al., JHEP 02 (2016) 111

Agarwalla et al., JHEP 05 (2012) 154

Courtesy Mauricio Bustamante
Alters neutrino detection cross sections

Agarwalla et al., JHEP 02 (2020) 038
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Novel Connections between Observables and BSM Scenarios in IceCube
A new multi-dimensional approach → four key observables of astrophysical neutrinos

Arguelles,
Bustamante,
Kheirandish,Palomares-Ruiz,
Salvado, Vincent,
PoS ICRC2019 (2020) 849

For applications, see:Song, Li, Arguelles,
Bustamante, Vincent,arXiv: 2012.12893 [hep-ph]energy spectrum, arrival directions, flavor composition, and arrival times to explore BSM Physics
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Ultimate Bounds on Long-Range Interactions

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Ultimate Bounds on Long-Range Interactions

ggravity ~ 10-19

Huge Electron repositories in the local and distant Universe
Oscillations sensitive to long-ranged flavored interactions
between neutrino and electron. Use flavor composition of
TeV-PeV astrophysical neutrinos at IceCube

Bustamante, Agarwalla PRL 122, 061103 (2019)
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Neutrino Non-Standard Interactions (NSIs)

NC-NSIs may explain
tension between
T2K and NOvA
See talk by
S. Chatterjee
See also,
Denton, Pestes
PRL 126 (2021) 5, 051801

NSIs in radiative
neutrino massmodels, See talkby S. Jana

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Neutrino NC-NSIs in Propagation
dimension-6
4-fermion
operators➡
Esteban, Gonzalez-Garcia, Maltoni, Martinez-Soler, Salvado, JHEP 08 (2018) 180
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Neutrino NC-NSIs in Propagation

Blue lines: All Oscillation data

Cyan lines: All Oscillation data + COHERENT data

Esteban, Gonzalez-Garcia, Maltoni, Martinez-Soler, Salvado, JHEP 08 (2018) 180
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Neutrino CC-NSIs at Production and Detection
dimension-6
4-fermion
operators➡
Farzan, Tortola, Front.in Phys. 6 (2018) 10
Ref. [13]: Agarwalla, Bagchi, Forero, Tortola, JHEP 07 (2015) 060
Ref. [33]: Biggio, Blennow, Fernandez-Martinez, JHEP 08 (2009) 090
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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New Constraints on Flavor-Diagonal NSIs from Borexino Phase-II

Nice complementarity between Borexino and Texono

one parameter at-a-time limit at 90% C.L. (1 d.o.f.)

S. K. Agarwalla et al., JHEP 02 (2020) 038

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Several Anomalies at Short-Baseline Experiments
Long-standing saga of eV-scale anomalies!
▸ LSND: 3.8!

[PRD 64 (2001) 22, 112007]▸ MiniBooNE (combined " and anti- "): 4.7!

[PRL 121 (2018) 22, 221801]▸ Reactor Antineutrino Anomaly: 3!
▸ Gallium Neutrino Anomaly: 3!
▸ NEOS: 3!

[PRD 83 (2011) 073006, PRC 84 (2011) 024617][PRC 83 (2011) 065504, PLB 795 (2019) 542]
[PRL 118, 121802 (2017)]▸ DANSS: 2.8!
▸ Neutrino-4: 2.8!

[PLB 787 (2018) 56][JETP Lett. 109 (2019) 4, 213]

See talks by S. H. Seo, A. Minotti, M. Danilov, A Serebrov, R. Samoilov, A. Fomin
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Significant tension between appearance and disappearance results

Dentler, Hernandez-Cabezudo, Kopp, Machado, Maltoni, Martinez-Soler, Schwetz, JHEP 08 (2018) 010

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Very Short-Baseline Reactor Experiments

DANSS: Kalinin Nuclear Power Plant (KNPP), Moscow, Russia
Neutrino-4: SM-3 Research Reactor at Dmitrovgrad, Russia
SoLid: SCK-CEN BR2 Research Reactor in Belgium

NEOS: Hanbit Nuclear Power Complex in Yeong-gwang, Korea
PROSPECT: High Flux Isotope Reactor (HFIR) at ORNL, USA
STEREO: High Flux Reactor of the Institute Laue-Langevin, France

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Present and Future Sensitivity from Very SBL Reactor Experiments

Present Sensitivity

Future Sensitivity
PWR = Pressurized Water Reactor
HFIR: High Flux Isotope Reactor

Courtesy Bryce Littlejohn

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Fermilab: Short-Baseline Neutrino Appearance Oscillation Sensitivity

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Fermilab: Short-Baseline ! Disappearance Oscillation Sensitivity

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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First Study on θ23 Octant with Light Sterile Neutrino

sin2!23 = 0.42 (LO) and 0.58 (HO)●Three-flavor ellipses due tovariation in δ13 in [-π to π]●

Four-flavor blobs due tovariation in δ13 and δ14 in [-π to π]●

Due to new CP phases, sensitivity
towards octant lost in DUNE

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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CPT and Lorentz Symmetry Violation▸ Unified theories, such as string theory, allow for violation of Lorentz symmetry
by inducing new spacetime structure at the quantum gravity scale▸ The direct observation of Lorentz Invariance Violation (LIV) at low-energy
would provide access to the Planck-scale (Mp) physics☞ Introduce LIV or CPT violation in the framework

If one extends the SM to include LIV/CPT-violating terms using the SME framework:

We assume that “a” and “c” only have a time component:
Kostelecky, Mewes, PRD 69 (2004) 016005
For a comprehensive list of the constraints on all the relevant LIV/CPT-violating parameters, see
Kostelecky, Russel, RMP 83 (2011) 11, arXiv:0801.0287v13 [hep-ph]
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Current Bounds on LIV using IceCube Atmospheric Neutrino Data

Nature Phys 14, 961–966 (2018)
Very strong limits on LIV induced by dimension-six operators!
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Neutrino Decays (Visible and Invisible)▸ Various new physics models predict neutrino decay

Chikashige, Mohapatra, Peccei, PLB 98 (1981) 265
Gelmini, Roncadelli, PLB 99 (1981) 411; Gelmini, Valle, PLB 142 (1984) 181
scalar▸ Invisible decay: either the decay products are sterile neutrinos, or have sufficiently
low energy avoiding detection▸ Visible decay: involves regeneration of lower energy neutrinos and provides
additional detection signatures▸ Invisible decay: ν3 → sterile neutrino + Majoron (m! ≲ m#)☞ Existing bounds:▸ Super-Kamiokande + K2K + MINOS:
τ3/m3 > 2.9 × 10-10 s/eV at 90% C.L.
Gonzalez-Garcia, Maltoni, PLB 663 (2008) 405▸ T2K + MINOS:
τ3/m3 > 2.8 × 10-12 s/eV at 90% C.L.
Gomes, Gomes, Peres, PLB 740 (2015) 345

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Neutrino Decays (Visible and Invisible)☞ Expected bounds:▸ T2K + NOvA:
τ3/m3 > 1.5 × 10-12 s/eV at 3! C.L.
Choubey, Dutta, Pramanik, JHEP 08 (2018) 141▸ ICAL@INO (500 kt·yr exposure):τ3/m3 > 1.51 × 10-10 s/eV at 90% C.L.
Choubey, Goswami, Gupta, Lakshmi, Thakore
PRD 97 (2018) 3, 033005▸ DUNE (40 kt, 5 yr " + 5 yr anti- "):τ3/m3 > 4.5 × 10-11 s/eV at 90% C.L. for NO
Choubey, Goswami, Pramanik, JHEP 02 (2018) 055▸ KM3NeT-ORCA (after 10 years of run):τ3/m3 > 2.5 × 10-10 s/eV at 90% C.L.
de Salas, Pastor, Ternes, Thakore, Tortola
PLB 789 (2019) 472▸ JUNO:τ3/m3 > 7.5 × 10-11 s/eV at 95% C.L.
Abrahao, Minakata, Nunokawa, Quiroga JHEP 11 (2015) 001☞ Limits from CMB:
Hannestad, Raffelt, PRD 72 (2005) 103514; Escudero, Fairbairn, PRD 100 (2019) 10, 103531☞ Limits from Solar Neutrinos:Berryman, de Gouvea, Hernandez, PRD 92 (2015) 7, 073003☞ Invisible " decay (τ/m = 102 s/eV) resolves IceCube’s track & cascade (> 3!) tension:
Denton, Tamborra, PRL 121, 121802 (2018)☞ Visible decay:
MINOS + T2K: Gago, Gomes, Gomes, Jones-Perez, Peres, JHEP 11 (2017) 022
DUNE: Coloma, Peres, e-Print: 1705.03599 [hep-ph]
S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Concluding Remarks
High-energy astrophysical neutrinos detected by big neutrino telescopes may
reveal the presence of new fundamental particles and interactions, probingenergy and distance scales far exceeding those accessible in the laboratory
Various BSM scenarios may affect the outcome of next generation high-precision
neutrino oscillation experiments as the precision on the neutrino oscillation
parameters and CP violation measurements continues to improve in the near
future
BSM physics may become the dominant physics topics of next generation
neutrino experiments!
So stay tuned!
I apologize for missing your important work, time is too short to cover everythingThank you!

S. K. Agarwalla, 20th Lomonosov Conference, Moscow State University, Moscow, Russia, 25th August, 2021

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Motivation for BSM Searches in Neutrino Experiments▸ Physics beyond the Standard Model (BSM) has manifested itself in one clear way– neutrino masses are non-zero▸ Rich experimental program in neutrino physics for the coming decade or two tovalidate the three-neutrino paradigm and to have extensive search for BSM physics▸ The upcoming high-precision neutrino oscillation experiments are expected todetermine the neutrino mass ordering, mixing angles, and CP violation at high C.L.
and to provide a rigorous test of the three-flavor neutrino oscillation framework at
various baselines (L) and energies (E) in the presence of Earth’s matter effect▸ These facilities are supposed to measure the mixing angles and mass-squared
differences with a precision around few % and therefore, these next generation
neutrino experiments may be sensitive to various BSM scenarios at low-energies▸ BSM searches in low-energy neutrino experiments complement the quest for new
physics at the ongoing LHC and future collider facilities at high-energies

Few Interesting Issues in Neutrino BSM Physics▸ To what extent does the three-flavor neutrino oscillation framework describe Nature?
▸ Can future high-precision neutrino oscillation experiments reveal the presence of new
fundamental particles or interactions?
▸ How do the oscillation parameters get modified in the presence of flavor conserving andflavor violating non-standard interactions (NSIs) of the neutrino inside the Earth matter?
▸ Can we Improve the constraints on NSIs using upcoming scattering and oscillation data?
▸ How many neutrino species are there? Do sterile neutrinos exist? How can they affect themeasurements of various oscillation parameters in neutrino experiments?
▸ Possibility of new sources of CP violation due to the new phases with a light sterile neutrino?
▸ How can we discriminate between various new physics models in neutrino experiments?
▸ Importance of second oscillation maximum, spectral information, near detector, highly
precise tracking and energy measurements, low energy thresholds, excellent timing
resolution, charge identification capabilities, hadron energy information (inelasticity)▸ Machine learning techniques in data analysis to develop improved selection criteria

Current Bounds on LIV using IceCube Atmospheric Neutrino Data

2 years of IceCube data ~ 35,000 atmospheric muon
neutrino events with E < 20 TeV and -1<cos!<0.2Current Bounds on LIV using Super-K Atmospheric Neutrino Data
PRD 91 (2015) 052003

Current Bounds on LIV using IceCube Atmospheric Neutrino Data

Effective Hamiltonian derived
from the Standard Model Extension
× marks the best-fit point:
compatible with the absence of LIV

Wilk’s theorem with 3 d.o.f. used
Red (Blue): 90% (99%) C.L.
exclusion regions

Exploring Intrinsic LIV @ DUNE

Berenboim, Masud, Ternes, Tortola, PLB 788 (2019) 308

Ref. [11]: Super-K (1410.4267)

Can LIV affect the Sensitivity of DUNE?

Agarwalla, Masud, 1912.13306 [hep-ph]Unitarity Constraints

Parke, Ross-Lonergan, PRD 93 (2016) 11, 113009

Unitarity Constraints

Triangles no longer close
Parke, Ross-Lonergan, PRD 93 (2016) 11, 113009

CP violation in DUNE with non-unitary mixing

Escrihuela, Forero, Miranda, Tortola, Valle, NJP 19 (2017) 9, 093005

Search for Millicharged Particles (MCPs)

0.24 ton LArTPC placed in the NuMI
beam line at Fermilab for five months

Harnik, Liu, Palamara, JHEP 07 (2019) 170

ArgoNeuT Collaboration, PRL 124, 131801 (2020)

MCPs (electric charge Q! = "e where " « 1) mostly
violate the quantization of charge seen in the SM andcould make up part of the DM in the Universe
MCPs mainly produced at any intense fixed-target
produced beam via the decays of neutral meson anddetected via elastic scattering with electrons
ArgoNeut search for an event signature with two soft
hits (MeV-scale energy depositions) aligned with the
upstream target and sensitive to MCPs with charges
between 10-3e and 10-1e with masses in the range
Magill, Plestid, Pospelov, Tsai, PRL 122, 071801 (2019)from 0.1 to 3 GeV