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A.A. Kwiatkowski
Department of Physics & Astronomy and Cyclotron Institute
Texas A&M University
Mass measurements needed for neutrino physics
Coherent Neutrino Scattering Experiment Workshop
12 November 2015
Many disciplines require atomic mass measurements at different precisions.
General PhysicsMetrology, tests of
CPT
dm/m ≤ 10-10
Neutrino Physicsdm/m ≤ 10-11
Nuclear
Astrophysicsdm/m ≤ 10-7
Nuclear PhysicsMass models &
formulae
dm/m ≈ 10-7
Weak
InteractionsTests of fundamental
symmetries
dm/m ≤ 10-9
Atomic PhysicsBinding energies and
tests of QED w/ HCI
dm/m ≤ 10-9
Nuclear b decay is the most suitable process to investigate neutrinos.
Neutrino PhysicsdQ ~ 0.1 - 100 eV
Neutrino MassdQ < 1 eV
Neutrinoless Double-beta
DecaydQ = 10 - 100 eV
Search for Sterile
NeutrinosdQ ≤ 100 eV
Neutrino OscillometrydQ = 10 - 100 eV
Neutrino Physicsdm/m ≤ 10-11
𝑄 = 𝑀𝑖 − 𝑀𝑓
Total energy carried away by
emitted neutrino is shared with
emitted electron(s) in b & bb and
is constant in e & ee.
Penning traps are trusted for high-accuracy and -precision mass spectrometry.
𝐁
z0
r0
ring
electrode
end cap
ion
Mass determination via cyclotron frequency
2pnc = (q/m) B
𝐁
= =+V
z
B
q/m
n+ = reduced cyclotron freq. ~ 1 MHz
n- = magnetron freq. ~ 1 kHz
nz = axial freq. ~ 100 kHz
Achievable precision distinguishesmeasurement techniques.
𝛿𝜈𝑐 𝜈𝑐 < 10−10
𝜈𝑐2 = 𝜈+
2 + 𝜈−2 + 𝜈𝑧
2
stable or long-lived species
𝛿𝜈𝑐 𝜈𝑐 ≥ 10−10
𝜈𝑐 = 𝜈+ + 𝜈−
short-lived species
I
t
I
n
FFT
n
TOF
TITAN
CPT
LEBIT
JYFLTRAP
ISOLTRAP
MLLTRAP
FSU
THe-TRAP
PENTATRAP
TRIGATRAP
SHIPTRAP
CHIP-TRAP
PTMS has spread worldwide.
short-lived nuclides
dm/m ~ 10-9
long-lived & stable
nuclides
dm/m <10-10
KATRIN will directly measure 𝑚 𝜈
through kinematics of 𝑇𝛽−3𝐻𝑒.
𝑁 ∝1
𝐸03
Want lowest 𝑄𝛽− : 3H 3He 𝑄𝛽− = 18.6 keV 𝑇1/2 = 12.3 y KATRIN
187Re 187Os 𝑄𝛽− = 2.5 keV 𝑇1/2 = 44 Gy MARE
THe-TRAPaim
𝛿𝑄(𝑇𝛽− 3𝐻𝑒) ≈ 20 meV
𝛿𝑄 𝑚 < 10−11
PENTATRAP, CHIP-TRAPaim
𝛿𝑄(187𝑅𝑒𝛽− 187𝑂𝑠) ~ 1 eV
ECHo will directly measure 𝑚𝜈through kinematics of 163𝐻𝑜 163𝐷𝑦
Inte
nsity
De-Excitation Energy / keV
Want lowest 𝑄 : 163Ho 163Dy 2.2 ≤ 𝑄 ≤ 2.8 keV 𝑇1/2 = 4.6 ky
( Additional candidates whose 𝑄 < 100 keV since 𝐸𝜈 = 𝑄 − 𝐵𝑖. )
SHIPTRAP(2015)
𝛿𝑄 = 16 eV
PENTATRAP
CHIP-TRAPaim
𝛿𝑄 ~ 1 eV
The Double b-decay problem
double-electron-capture nuclides
double b-decay nuclides
0nbb experiments rely on kinematics.
0n2bT1/2>10-25
2n2bT1/2~10-19
E/Qbb
dN
/d (
E/Q
bb)
100
em
mMZQGT
bb
nbbbbnn ||),()( 00
10
2/1
phase-space factor effective Majorana
mass
nuclear matrix element
FSU, LEBIT, JYFLTRAP, SHIPTRAP, TITAN,
TRIGATRAP, …(g.s. g.s.)
𝛿𝑄𝛽𝛽 , 𝛿𝑄 ≤ 1 keV
𝛿𝑄 𝑚 ≤ 10−9
0𝜈휀휀 decay may be resonantly enhanced.
1
𝑇1/2∝
Γ
𝑄 − 𝐵2ℎ − 𝐸𝛾2+ Γ 2 2
degeneracy Δ = 𝑄 − 𝐵2ℎ − 𝐸𝛾 ≈ Γ < 100 eV
requires δ𝑄 ≈ 100 eV
Hunts for sterile neutrinos need 𝑄& accurate electron wavefunctions.
Inte
nsity
De-Excitation Energy / keV
𝜆𝑖𝜆𝑗 𝑡ℎ= 𝐹(𝑄 , 𝐵𝑖 , 𝐵𝑗 , 𝑈𝑒4) ∙
𝜆𝑖𝜆𝑗 𝑒𝑥𝑝
binding energy of ith, jth e-
contribution from
sterile neutrino
𝜆𝑖 𝜆𝑗 𝑡ℎrequires accurate e- wavefunctions
and high-accuracy & -precision 𝑄 -values.
Next steps in oscillometrydepend on neutrino source.
LENA
50 kt
liquid
scintillator
• Oscillation length:
𝐿𝑖𝑗 𝑚 ∝𝐸𝜈 [𝑀𝑒𝑉]
|∆𝑚𝑖𝑗|2 [𝑒𝑉]
• If En ~ keV then L13 ~ m
• An intense tunable keV n source can be made with accelerated b emitters / electron-capture decay:
37Ar, 51Cr, 75Se, 113Sn, 145Sm, 169Yb
Some Q-values for solar neutrino experiments require re-examination.
• SAGE & GALLEX measured solar ne flux via 71Ga(ne,e
-)71Ge reaction over 15 year period
• Deficit in measured-to-predicted event ratio of 13% or 2.6s
• TITAN measured 𝛿𝑄 = 1.2 keV …
& soon JYFLTRAP 𝛿𝑄 < 1 keV
source event ratio
exp / theory
GALLEX 51Cr 0.882±0.078
SAGE 51Cr 0.95± 0.12
SAGE 37Ar 0.79±0.10
average 0.87±0.05
detector calibration with terrestrial sources
SAGE
Summary & status
• Neutrino mass Q-values needed:
• SMILE-TRAP measured 𝛿𝑄 3𝐻 = 1.2 eV
• THe-TRAP can do 𝛿𝑄 𝑚 ~ 10−10 & will do <10−11
• PENTATRAP & CHIP-TRAP are under construction & aim for 𝛿𝑄 163𝐻𝑜, 187𝑅𝑒 ~ 1 eV
• 0𝜈𝛽𝛽 and 0𝜈휀휀 decay Q-values have largely been measured to desired precision at RIB PTMS
• Still need NME and Ex to identify enhanced cases
• Hunt for sterile neutrinos• Candidates identified but
largely unmeasured to desired precision of 𝛿𝑄 ≤ 100 eV
• Mapping oscillations:• Ongoing effort, beginning to
be examined at RIB PTMS• keV neutrino candidates
require 𝛿𝑄 ≤ 100 eV• Solar neutrino flux
experiments require 𝛿𝑄~ 100 eV
References
• S. Eliseev, Y.N. Norikov, K. Blaum, AdP 525 (2013) 707
• S. Eliseev, T. Eronen, Y.N. Norikov, IJMS 349 (2013) 102
• K. Blaum, S. Eliseev, T. Eronen, Y. Litvinov, JPCS 381
(2012) 010213
7s shift in Qe(163Ho) published this August!
• S. Eliseev et al., PRL 115 (2015) 062501
Many figures were taken from Sergey Eliseev – thank you!