The 𝐂𝐄𝝂𝐍𝐒 p ocess is sensi i e o he weak mixing angle and o he neu on nuclea
adius. The wo quan i ies a e in insically co ela ed wi hin he c oss sec ion.
The CE𝝂NS F on ie
P ecision p obe o he S anda d Model and beyond
Ma ia A zo i Co ona ([email p o ec ed]n.i ), INFN To Ve ga a
The esul s p esen ed a e in collabo a ion wi h: M. Cadeddu, N.Ca gioli, F. Do dei, C.
Giun i & R. Pa a ani
Spalla ion Neu on Sou ce (SNS)
𝜋decay-a - es (~ 30 MeV)
Pulsed neu ino sou ce
Reac o Neu inos
P oduced a nuclea powe plan (∼ 1 − 12 MeV)
Only ҧ𝜈𝑒
Cesium Iodine
Phys.Re .Le . 129 (2022) 8,
081801
11.6 𝝈 signi icance
14.6 kg c ys al, 19.3 m
∼ 7 keVn h eshold
∼320 e en s obse ed
Reac o CE𝝂NS on Ge manium
CONUS+ Obse a ion @ Leibs ad
(Swi ze land), Na u e 643, 1229–1233
(2025)
3.7 𝝈Obse a ion (≃𝟑𝟗𝟓 𝐞𝐯𝐞𝐧𝐭𝐬)!
∼ 1 keVn h eshold, 3.73 kg
Reac o de ails: 𝑃 = 3.6 GW h, L=20.7 m
Addi ional measu emen s:
𝝂GeN Chinese Phys. C 49 053004 (2025)
TEXONO Phys.Re .Le . 134 (2025) 12, 121802
Cohe en Elas ic Neu ino-Nucleus Sca e ing
F eedman, PRD 9, 1389 (1974)
𝜈 + 𝑍
𝐴N→ 𝜈 + 𝑍
𝐴N
The de B oglie wa eleng h o he exchanged 𝑍0
is o he o de o he adius o he nucleus.
•All he nucleons espond cohe en ly
( ecoils as a whole)
•Rela i ely la ge c oss sec ion ∝ 𝑁2
compa ed o o he low ene gy neu ino in e ac ions.
CE𝜈NS is a e y use ul p obe o explo e ex ension o he S anda d Model ea u ing new
media o s.
𝑟𝜈ℓ
2
SM →
𝑟𝜈𝑒
2
𝑆𝑀 = −8.2 × 10−33𝑐𝑚2
𝑟
𝜈𝜇
2
𝑆𝑀 = −4.8 × 10−33𝑐𝑚2
𝑟𝜈𝜏
2
𝑆𝑀 = −3.0 × 10−33𝑐𝑚2
CE𝝂NS C oss Sec ion
𝒅𝝈
𝒅𝑻𝐧𝐫
≅𝑮𝑭
𝟐𝒎𝑵
𝝅𝟏 − 𝒎𝑵𝑻𝐧𝐫
𝟐𝑬𝝂
𝟐𝒈𝑽
𝒑𝒁𝑭𝒁𝒒𝟐+𝒈𝑽
𝒏𝑵𝑭𝑵𝒒𝟐𝟐
CE𝝂NS egime
(𝑬𝝂≲𝟏𝟎 MeV)
F om EPL 143 (2023) 3, 34001
MAC, PhD Thesis
Elec oweak couplings wi h p o ons and neu ons Nuclea Fo m Fac o s (FF): he ini e size o he nucleus ma e s
Wi h adia i e co ec ions
𝑔𝑉
𝑝𝜈𝑒∼ 0.0382
𝑔𝑉
𝑝𝜈𝜇∼ 0.0299
𝑔𝑉
𝑝𝜈𝜏∼ 0.0255
𝑔𝑉
𝑛= −0.5117
Fla o dependen !
T ee le el: Fla o independen
couplings
𝑔𝑉
𝑝=1
2− 2𝐬𝐢𝐧𝟐𝜽𝑾≃ 0.02274
𝑔𝑉
𝑛= −0.5
MAC e al.
JHEP 05 (2024) 271
The expe imen is pe o med a 𝑞2≠ 0 →
la o dependen adia i e co ec ion
P o ons
•Nuclea dis ibu ion well known
A om. Da a Nucl. Da a Tabl. 60, 177–285 (1995))
Neu ons
•Nuclea dis ibu ion
poo ly known
•Neu inos can be used a
mic oscope o p obe he
neu on dis ibu ion
𝑍=55
N=78Cs
Symme ized
Fe mi
/𝜌0
Fo m Fac o : 𝐹 𝑞 = 𝑑3𝑥 𝜌 𝑥 𝑒𝑖𝑞⋅𝑥 < 𝟏
Supp ession o he c oss sec ion
*O he low-ene gy sou ces could be conside ed, bu a e no included in his pos e .
Reac o Flux
PRC 108 (2023) 5,
055501
⟨𝑬𝝂⟩ ≃ 𝟐 MeV
𝝂𝝁
P o on
(1 GeV)
Hg
ഥ
𝝂𝝁+ 𝝂𝒆
ഥ
𝝂𝒆
ഥ
𝝂𝒆
ഥ
𝝂𝒆ഥ
𝝂𝒆
CsI 2022
MAC e al. EPJ.C 83 (2023)7,683
A SNS (𝐸𝜈<50 MeV) he nuclea s uc u e
plays a majo ole.
CsI 2022 da a show ∼ 6 𝜎 e idence o he
supp ession o he ull cohe ence!*
𝑹𝒏𝟏𝟑𝟑𝐂𝐬 ≃ 𝑹𝒏(𝟏𝟐𝟕𝐈) = 𝟓. 𝟒𝟕 ± 𝟎. 𝟑𝟖 m
*Ob ained wi h ixed alue o he weak mixing angle a low-ene gies.
A eac o s (𝐸𝜈<10 MeV) he FF a e ∼1.
The ex ac ion on he weak mixing angle is
no dependen on he nuclea neu on adius
CsI+A +Ge+Reac o s
𝐬𝐢𝐧𝟐𝜽𝑾𝒒𝟐→ 𝟎 ≃ 𝟎. 𝟐𝟐𝟗−𝟎.𝟎𝟏𝟗
+𝟎.𝟎𝟐𝟎
Elec oweak combined
𝐬𝐢𝐧𝟐𝜽𝑾𝒒𝟐→ 𝟎 ≃ 𝟎. 𝟐𝟑𝟗𝟔 ± 𝟎. 𝟎𝟎𝟏𝟕
MAC e al. 2506.13555
& Phys.Re .D 112 (2025)
1, 015007
MAC e al.
PRD
110 (2024) 3, 033005
Re .Mod.Phys.
87 (2015) 531
The neu ino cha ge adius is he only neu ino elec omagne ic p ope ies di e en
om ze o in he s anda d model. Neu inos a e neu al pa icles, he e o e, hey can no
couple di ec ly wi h pho ons → 𝟏 loop diag ams a e needed
The NCR modi ies he neu ino-p o on coupling h ough:
𝑔𝑉
𝑝≃1
2− 2 sin2𝜃𝑊−2𝜋𝛼𝐸𝑀
3𝐺𝐹
𝒓𝝂ℓ
𝟐
𝐞𝐟𝐟 + la o independen adia i e co ec ion
•CE𝜈NS da a p o ides a e y powe ul and
inno a i e me hod o s udy he de ails o he 𝜈-
nucleon in e ac ion e ex
•A 1 𝜎 we ind
𝒆 − la o
𝝁 − la o
𝑟
𝜈𝑒
2= 3.2 ± 4.7 × 10−32cm2
𝑟
𝜈𝜇
2= −3.9−2.7
+2.8 ×10−32cm2
MAC e al, JHEP 05 (2024) 271
Assuming such non s anda d neu ino in e ac ion (NSI), he Lag angian is
In his amewo k, he media o mass is ≫ han he momen um
ans e → high media o mass limi
L=−2 2𝐺𝐹σℓ=𝑒,𝜇 𝜈ℓ𝐿𝛾𝜌𝜈ℓL σ𝑓=𝑢,𝑑 𝜖ℓℓ
𝑓𝑉(ҧ
𝑓𝛾𝜌𝑓) Fla o p ese ing NSI
The weak cha ge is modi ied acco ding o
𝑄ℓ,NSI
𝑉= (𝑔𝑉
𝑝𝜈ℓ+ 2𝜖ℓℓ
𝑢𝑉 + 𝜖ℓℓ
𝑑𝑉)𝑍𝐹𝑍𝑞2+ (𝑔𝑉
𝑛+ 𝜖ℓℓ
𝑢𝑉 + 2𝜖ℓℓ
𝑑𝑉) 𝑁 𝐹𝑁𝑞2
𝜖ℓℓ
𝑓𝑉 =𝑔𝑍′
2
2𝐺𝐹Ԧ𝑞 2+ 𝑚𝑍′
2
In e m o he mass (𝑚𝑍′) & coupling (𝑔𝑍′): ligh media o s!
CE𝝂NS
Low-Ene gy 𝝂∗CE𝝂NS Measu emen s
Liquid A gon
Phys.Re .Le . 126 (2021) 1,
01200213
3.5 𝝈 signi icance
24.4 kg, 27.5 m
∼20 keVn h eshold
∼120 e en s obse ed
Ge manium
Phys.Re .Le . 134 (2025) 23, 231801
3.9 𝝈 signi icance, 10.66 kg
∼ 7 keVn h eshold
∼2 𝝈 ension wi h he SM
Ag eemen among he
di e en CEνNS da a,
sepa a ing he con ibu ion
om he di e en la o s.
90% CL
MAC e al., Phys.Le .B
869 (2025) 139856
Elec oweak and Nuclea Physics Sea ches o new media o s
Neu ino Cha ge Radius Towa d p ecision physics wi h CE𝝂NS
MAC e al., Phys.Le .B 869 (2025) 139856
Uni e sal model
𝑍′
In he Uni e sal model, he new cha ges
a e all equal o one.
COHERENT C yo-CsI
C yo-CsI I (II): 10 700 kg
o undoped CsI
∼ 0.5 keVn h eshold
∼1000 e en s/SNS-yea
wi h C yo-CsI I @ 19 m om
SNS
COHERENT is de eloping an in ense expe imen al p og am o
enable p ecision physics es s wi h CE𝜈NS. SNS upg ades a e
o eseen, as well as a dedica ed campaign o p ecisely de e mine he
neu ino lux (COH-Collabo a ion: Phys.Re .D 109 (2024) 9, 092005).
Liquid A gon - 750
750(610) kg o ac i e
( iducial) mass
∼20 keVn h eshold
∼5000 e en s/SNS-yea
Two scena ios: sys ema ic
unce ain y 8% and 5%.
To lea n mo e, check
ou ou websi e!
See MAC e al.,
a Xi : 2509.04205
See MAC e al.,
a Xi : 2509.04205
