Cosmic Neutrino Background (CvB): properties and detection...
Transcript of Cosmic Neutrino Background (CvB): properties and detection...
Cosmic Neutrino Background (CvB): properties and detection
perspectives
Gianpiero ManganoGianpiero Mangano
INFN, Sezione di Napoli, INFN, Sezione di Napoli, ItalyItaly
-αα
-α
-α
βαβα
βαβα
eeee+↔
↔
↔
↔
νν
νν
νννννννν
Tν = Te = Tγ
1 MeV ≤ T ≤ mµ
Relic neutrino production and decoupling
Neutrino decoupling
As the Universe expands, particle densities are diluted and temperatures fall. Weak interactions become ineffective to keep neutrinos in good thermal contact with the e.m. plasma
Rate of weak processes ~ Hubble expansion rate
MeV T MπρT G
Mπρ n , HσΓ ν
decp
RF
p
Rww 1
38
38v 2
522
2 ≈→≈→=≈
Rough, but quite accurate estimate of the decoupling temperature
Since νe have both CC and NC interactions with e±
Tdec(νe) ~ 2 MeVTdec(νµ,τ) ~ 3 MeV
At T~me, electron-positron pairs annihilate
heating photons but not the decoupled neutrinos
γγ→+ -ee
Neutrino and Photon (CMB) temperatures
1e1T)(p,f p/T +
=νν
1/3
411
TT
⎟⎠⎞
⎜⎝⎛=
ν
γ
At T~me, electron-positron pairs annihilate
heating photons but not the decoupled neutrinos
γγ→+ -ee
Neutrino and Photon (CMB) temperatures
1e1T)(p,f p/T +
=νν
1/3
411
TT
⎟⎠⎞
⎜⎝⎛=
ν
γ
Photon temp fallsslower than 1/a(t)
• Number density
• Energy density
323
3
113(6
113
2 CMBγννν Tπ
)ζn)(p,Tfπ)(pdn === ∫
⎪⎪⎪
⎩
⎪⎪⎪
⎨
⎧⎟⎠⎞
⎜⎝⎛
→+= ∫νν
νν
π
ρnm
T
)(p,Tfπ)(pdmp
i
ii
CMB
νν
43/42
3
322
114
1207
2
Massless
Massive mν>>T
Neutrinos decoupled at T~MeV, keeping a spectrum as that of a relativistic species 1e
1T)(p,f p/T +=
νν
• Number density
• Energy density
323
3
113(6
113
2 CMBγννν Tπ
)ζn)(p,Tfπ)(pdn === ∫
⎪⎪⎪
⎩
⎪⎪⎪
⎨
⎧⎟⎠⎞
⎜⎝⎛
→+= ∫νν
νν
π
ρnm
T
)(p,Tfπ)(pdmp
i
ii
CMB
νν
43/42
3
322
114
1207
2
Massless
Massive
mν>>T
Neutrinos decoupled at T~MeV, keeping a spectrum as that of a relativistic species 1e
1T)(p,f p/T +=
νν
At present 112 per flavour cm )( -3νν +
Contribution to the energy density of the Universe
eV 94.1
mh Ω i
i2
∑=ν
52 101.7h Ω −×=ν
At T<me, the radiation content of the Universe is
Relativistic particles in the Universe
γνγνγ ρππρρρ⎥⎥⎦
⎤
⎢⎢⎣
⎡⎟⎠⎞
⎜⎝⎛+=××+=+= 3114
871
15873
15
3/44
24
2
r TT
At T<me, the radiation content of the Universe is
Effective number of relativistic neutrino speciesTraditional parametrization of the energy densitystored in relativistic particles
Relativistic particles in the Universe
data) (LEP 008.0984.2 ±=νN# of flavour neutrinos:
• Extra radiation can be:
scalars, pseudoscalars, sterile neutrinos (totally or partially thermalized, bulk), neutrinos in very low-energy reheating scenarios, relativistic decay products of heavy particles…
• Particular case: relic neutrino asymmetries
Constraints from BBN and from CMB+LSS
Extra relativistic particles
At T~me, e+e- pairs annihilate heating photons
γγ→+ -ee
fν=fFD(p,Tν)[1+δf(p)]
CvB details
… and neutrinos. Non thermal features in v distribution (small effect). Oscillations slightly modify the result
( ) )(C,Em
G28p
MHpi 2W
F2
pt ρρρ +⎥⎥⎦
⎤
⎢⎢⎣
⎡−=∂−∂
νeνµ,τ
δf x102
1ep
p/T
2
+
10-2 effect
3.0460.520.520.731.3978+3ν mixing(θ13=0)
3.0460.430.430.941.3978SM
30001.40102Instantaneous decoupling
0.52
δρντ(%)
3.0460.560.701.3978+3ν mixing(sin2θ13=0.047)
Neffδρνµ (%)δρνe(%)γγ
0/TTfin
G.M. et al, NPB 729 (2005) 221
Results
Dolgov, Hansen & Semikoz, NPB 503 (1997) 426G.M. et al, PLB 534 (2002) 8
Effect of neutrinos on BBN1. Neff fixes the expansion rate during BBN
ρ(Neff)>ρ0 → ↑ 4He
38ππ H ρ
=
2. Direct effect of electron neutrinos and antineutrinos on the n-p reactions
γγ ρρρρρ ⎟⎟⎠
⎞⎜⎜⎝
⎛⎟⎠⎞
⎜⎝⎛+=++= v
effxvR N
3/4
114
871
0 2 4 6 8
-40
-20
0
20
40
60
80
7Li3He
D
4He
BBN: allowed ranges for Neff
Using 4He + D data (95% CL)
1.41.2 eff 3.1N +−=
2B10
B10 h274Ω
10/nn
η ≅= −γ
νν nn ≠
[ ]323
TT
)3(121
nnnL νν
γ
ν
γ
ννν ξξπ
ζ+⎟
⎟⎠
⎞⎜⎜⎝
⎛=
−=
⎥⎦
⎤⎢⎣
⎡⎟⎠⎞
⎜⎝⎛+⎟
⎠⎞
⎜⎝⎛=
42
2715
πξ
πξρ∆ νν
ν
Raffelt
Fermi-Dirac spectrum with temperature T and chemical potential µν=ξvTv
More radiation
CvB details
Hansen et al 2001 Hannestad 2003
Combined bounds BBN & CMB-LSS
4.2 22.001.0 , ≤≤≤− τµξξe
In the presence of flavor oscillations ?
Degeneracy direction (arbitrary ξe)
-0.2 0 0.2 0.4
ξe
-2
0
2
4
6
8
∆Nef
f
+
BBN
Evolution of neutrino asymmetries
07.0 ≤νξEffective flavor equilibrium(almost) established →
Dolgov et al 2002Wong 2002Abazajian et al 2002
07.005.0 ≤≤− ξ Serpico & Raffelt 2005
µν/Tv very small (bad for detection!)
BBN, CMB (LSS) + oscillations
µν/Tv
Hamann, Lesgourguesand GM 08
0.018 0.02 0.022 0.024 0.026 0.028 0.03
ωb
-0.2
0
0.2
0.4
ξ e
+µν/Tv
Cuoco et al 04
PLANCK
Departure from equilibrium?Pastor, Pinto Raffelt 2008
CvB for optimists
V produced by decays at some cosmological epoch
Early on: (TBBN> T>TCMB)
Late (T<< TCMB):
Unstable DM (e.g. Majoron)
dm0
v HΩΓΩ < 1.0
H0<
Γ
Lattanzi and Valle ’07
Lattanzi, Lesgourgues, GM and Valle (in progress)
Cuoco, Lesgourgues, GM and Pastor ‘05
Thermal FD spectrum
Distortion from Φdecay
ννΦ →
Present constraints from CMB (WMAP+ACBAR+VSA+CBI) and LSS (2dFGRS+SDSS) + SNIa data (Riess et al.)
Model: standard ΛCDM + nonthermal v’s
Cl and P(k) computed using CAMB code (Lewis and Challinor 2002)
Likelihoods (using COSMOMC Lewis and Bridle 2002))
3 3.2 3.4 3.6ln [1010 R
rad]
0.95 1 1.05 1.1n
0.02 0.0220.0240.026ω
b
0.15 0.2 0.25ω
dm
1.02 1.03 1.04 1.05θ
0.1 0.2 0.3τ
0.4 0.5 0.6β
0.5 1 1.5 2m
0
4 6 8 10N
eff
1 1.2 1.4 1.6 1.8q = ων (93.2 eV / m
0)
0.05 0.1 0.15A
10 20 30y
*
ΛCDM ΛCDM+R ΛCDM+NTχ2
min 1688.2 1688.0 1688.0ln[1010Rrad] 3.2±0.1 3.2±0.1 3.2±0.1ns 0.97±0.02 0.99±0.03 1.00±0.03ωb 0.0235±0.0010 0.0231±0.0010 0.0233±0.0011ωdm 0.121±0.005 0.17±0.03 0.17±0.03θ 1.043±0.005 1.033±0.006 1.033±0.006τ 0.13±0.05 0.13±0.06 0.15±0.07β 0.46±0.04 0.48±0.04 0.48±0.04m0 (eV) 0.3±0.2 0.8±0.5 0.7±0.4Neff 3.04 6±2 6±2q 1 1 1.25±0.13h 0.67±0.02 0.76±0.06 0.76±0.05Age (Gyr) 13.8±0.2 12.1±0.9 12.1±0.8ΩΛ 0.68±0.03 0.67±0.03 0.67±0.03zre 14±4 16±5 18±6σ8 0.76±0.06 0.77±0.07 0.77±0.07
TABLE I: Minimum value of the effective χ2 (defined as−2 lnL, where L is the likelihood function) and 1σ confi-dence limits for the parameters of the three models underconsideration. The first ten lines correspond to our basis ofindependent parameters, while the last five refer to relatedparameters.
CvB for pessimists
A neutrinoless Universe?
Models where v’s interact with light (pseudo)scalar particles
φφ
φφ
↔
++=
vv
chvvgvvhL jiijjiij ..
Beacom, Bell and Dodelson 2004
For the tightly coupled regime
v density strongly reduced, v’s play no role in LSS
Delay in matter domination epoch, different content in relativistic species after v decays (Neff=6.6 after decays)
couplings < 10-5 from several data (meson decay, 0ββ, SN)
Beacom, Bell and Dodelson 2004
Including CMB in the analysis:
•No free streaming (no anisotropic stress) leads to
smaller effects on LSS (for massive v’s)
change of sub-horizon perturbations at CMB epoch
•Change of sound speed and equation of state of the the titghlycoupled v - φ fluid
•v decays
larger Neff i.e. larger ISW effect for CMB
smaller effects on LSS (no v left at LSS formation epoch
Bell, Pierpaoli and Sigurdson 2005
Hannestad 2005
Massless interacting Massive decaying
Massive decaying
Usual picture of Dark Matter: cold collisionless massive particles whichdecoupled around the weak scale for freeze-out of annihilation processes
Ex: neutralino in MSSM with mass of O(100 GeV)
Difficulties:
Excess of small scale structures
Far more satellite galaxies in the Milky Way than observed (from numericalsimulation)
DM in the MeV range: SPI spectrometer on the INTEGRAL satellite observed a bright 511 KeV gamma line from the galactic bulge
Boehm, Fayet and Silk 2003−+→ eeψψ
Interacting v-DM
Framework: light (MeV) DM interacting with neutrinos
Several options for lagrangian density
Effects on cosmological scales: if DM - v’s scatterings at work duringLSS formation we expect an oscillating behavior in the power spectrum (analogous to baryon – photon fluid during CMB epoch)
G.M., Melchiorri, Serra, Cooray and Kamionkowski 2006
Equation for velocity perturbations
Effect depends upon the parameter Q
mF ∫ mDM
mF = mDM
Bounds on differentialopacity Q from SDSS data
mDM∫ mF scenario almostruled out. Requires couplingof order one
mDM = mF still viable
CvB indirect evidences
T < eVT ~ MeV
Formation of Large Scale Structures
LSS
Cosmic Microwave Background
CMB
Primordial
Nucleosynthesis
BBN
Flavor blindflavor dependent
Effect of neutrinos on BBN
1. Neff fixes the expansion rate during BBN
38ππ H ρ
=
2. Direct effect of electron neutrinos and antineutrinos on the n-p reactions
γγ ρρρρρ ⎟⎟⎠
⎞⎜⎜⎝
⎛⎟⎠⎞
⎜⎝⎛+=++= v
eff3/4
xvR N114
871
0 2 4 6 8
-40
-20
0
20
40
60
80
7Li3He
D
4He
Effect of CvB on CMB and LSSMean effect (Sachs-Wolfe, M-R equality)+ perturbations
Melchiorri and Trotta ‘04
Integrated Sachs-Wolfe effectCMB anisotropies induced by passing through a time varying gravitational potential:
( )∫ Φ−= ττδ &dTT 2
δρπ 22 4 aG=Φ∇ Poisson’s equation
• changes during radiation domination• decays after curvature or dark energy come to dominate (z~1)
CMB+LSS: allowed ranges for Neff
• Set of parameters: ( Ωbh2 , Ωcdmh2 , h , ns , A , b , Neff )
• DATA: WMAP + other CMB + LSS + HST (+ SN-Ia)
• Flat Models
Non-flat Models
• Recent result
Pierpaoli, MNRAS 342 (2003)
2.01.9eff 4.1N +−=
95% CL
Crotty, Lesgourgues & Pastor, PRD 67 (2003)
3.32.1eff 3.5N +−=
95% CL
Hannestad, JCAP 0305 (2003)
3.02.1eff 4.0N +−=
Hannestad & Raffelt, astro-ph/06071014.6N2.7 eff <<
95% CL
Allowed ranges for Neff
G.M et al, JCAP 2006
Using cosmological data (95% CL)
)-Ly and BAO( 6.2N 3.1data) LSS(CMB 7.9N 3.0
eff
eff
α+<<
+<<
2B10
B10 h274Ω
10/nn
η ≅= −γ
…but maybe in the near future ?
Forecast analysis:CMB data
Bowen et al MNRAS 2002
∆Neff ~ 3 (WMAP)
∆Neff ~ 0.2 (Planck)
Bashinsky & Seljak PRD 69 (2004) 083002Example of futureCMB satellite
New effective interactions between electron and neutrinos
Bounds on non standard neutrino interactions
Electron-Neutrino NSI
Breaking of Lepton universality (α=β) Flavour-changing (α≠ β)
Limits on from scattering experiments, LEP data, solar vs Kamland data…
RL,αβε
Berezhiani & Rossi, PLB 535 (2002) 207Davidson et al, JHEP 03 (2003) 011Barranco et al, PRD 73 (2006) 113001
Analytical calculation of Tdec in presence of NSIAnalytical calculation of Tdec in presence of NSI
Contours of equal Tdec in MeV with diagonal NSI parameters
SM SM
Neff varying the neutrino decoupling temperatureNeff varying the neutrino decoupling temperature
Effects of NSI on the neutrino spectral distortions
Here largervariation for νµ,τ
Neutrinos keep thermal contact with e-γ until smaller temperatures
3.0460.520.520.731.3978+3ν mixing(θ13=0)
30001.40102Instantaneous decoupling
3.83
δρντ(%)
3.3573.839.471.3812εLee= 4.0
εRee= 4.0
Neffδρνµ (%)δρνe(%)γγ
0/TTfin
G.M. et al, NPB 756 (2006) 100
Results
Very large NSI parameters, FAR from allowed regions
3.0460.520.520.731.3978+3ν mixing(θ13=0)
30001.40102Instantaneous decoupling
0.52
δρντ(%)
3.1201.662.211.3937
εLee= 0.12
εRee= -1.58εL
ττ= -0.5εR
ττ= 0.5εL
eτ= -0.85εR
eτ= 0.38
Neffδρνµ (%)δρνe(%)γγ
0/TTfin
G.M. et al, NPB 756 (2006) 100
Results
Large NSI parameters, still allowed by present lab data
Mixing Parameters...From present evidences of oscillations from experiments measuring
atmospheric, solar, reactor and accelerator neutrinos
A.Marrone, IFAE 2007
... and neutrino massesData on flavour oscillations do not fix the absolute scale of neutrino masses
eV
atmatm
solar
solar
eV 0.009 ∆m
eV 0.05∆m2sun
2atm
≈
≈
NO
RMA
L
INVERTED
eV
m0
What is the value of m0 ?
Direct laboratory bounds on mνSearching for non-zero neutrino mass in laboratory experiments
• Tritium beta decay: measurements of endpoint energy
m(νe) < 2.2 eV (95% CL) Mainz
Future experiments (KATRIN) m(νe) ~ 0.2-0.3 eV
• Neutrinoless double beta decay: if Majorana neutrinos
experiments with 76Ge and other isotopes: ImeeI < 0.4hN eV
eν++→ -33 eHe H
-2e2)Z(A, Z)(A, ++→
Absolute mass scale searches
< 0.4-1.6 eVNeutrinolessdouble beta decay
< 2.2 eVTritium βdecay
2/122⎟⎠
⎞⎜⎝
⎛= ∑
iiei mUm
eν
< 0.3-2.0 eVCosmology ∑i
im~
∑=i
ieiee mUm 2
Cosmological bounds on neutrino masses using WMAP3
Fogli et al., hep-ph/0608060
Dependence on the data set used. An example:
Neutrino masses in 3-neutrino schemes
CMB + galaxy clustering
+ HST, SNI-a…+ BAO and/or bias
+ including Ly-α
J.Lesgourgues & S.Pastor, Phys. Rep. 429 (2006) 307
Tritium β decay, 0ν2β and Cosmology
Fogli et al.,
hep-ph/0608060
0ν2β and Cosmology
Fogli et al., hep-ph/0608060
CvB locally: a closer look
Neutrinos cluster if massive (eV) on largecluster scale
Escape velocity: Milky Way 600 Km/s
clusters 103 Km/s
)eV/m(s/Km106m/Tcv v3
vvv ⋅≈≈
How to deal with: Boltzmann eq. + Poisson
δρπφ∆
φ2
vvxv
Ga40amf xf
=
=∇−∂+ && Sing and Ma ’02
Ringwald and Wong ‘04
Milky Way (1012 MO)
.
@ Earth
Ringwald and Wong ‘04
.
Direct detection?
Detection I: Stodolsky effect
Energy split of electron spin statesin the v background
requires v chemical potential (Dirac) or net helicity(Majorana)
Requires breaking of isotropy (Earth velocity)
Results depend on Dirac or Majorana, relativistic/non relativistic, clustered/unclustered
Duda et al ‘01)nn(sgGE vvAF −⋅≈ ⊕β∆rr
The only well established linear effect in GF
Coherent interaction of large De Brogliewavelength
Energy transfer at order GF2
∫ ∇= )x(n(x) xdGF v3
F ρCabibbo and Maiani ’82
Langacker et al ‘83
Torque on frozen magnetized macroscopic piece of material of dimension R
23
vv3
27 s cmcm 100nn
10Rcm
A10010a −
−−⊕− ⎟
⎠⎞
⎜⎝⎛ −⎟⎠⎞
⎜⎝⎛⎟⎠⎞
⎜⎝⎛⎟⎠⎞
⎜⎝⎛≈
β
Presently Cavendish torsion balances 212 s cm10a −−≈
Detection II: GF2
V-Nucleus collision: net momentum transfer due to Earth peculiar motion
2v
2FvN EG=σ
v
vNA
vv
Ep
pANvna
⊕=
=
β∆
∆σ
v
v
Tpmp
⊕
⊕
=
=
β∆β∆
25446 s cm100A)1010(a −− −≈
Zeldovich and Khlopov ’81
Smith and Lewin ‘83
Coherence enhances
mm1/m - T/1 vvv ≈≈λ3v
Ac A
NN ρλ=
Backgrounds: solar v + WIMPS
Detection III
Accelerator: vN scattering hopeless
Cosmic Rays (indirect): resonant v annihilationat mZ eV
meV10 4
m2mE
v
21
v
2Z
⎟⎟⎠
⎞⎜⎜⎝
⎛≈=
Absorption dip (sensitive tohigh z)
Emission: Z burst above GZK (sensitive to GZK volume, (50 Mpc)3)
Ringwald ‘05
18 yr10R −−≈
LHC
Question: “Is it possible to detect/measure the CvB ?”
Answer: NO !
All the methods proposed so far require either strongtheoretical assumptions or experimental apparatushaving unrealistic performances
Reviews on this subject: A.Ringwald hep-ph/0505024G.Gelmini hep-ph/0412305
A ’62 paper by S. Weinberg and v chemical potential
In the original idea a large neutrino chemical potential distortsthe electron (positron) spectrum near the endpoint energy
Massive neutrinos and neutrino capture on beta decaying nuclei
A.G.Cocco, G.Mangano and M.Messina JCAP 06(2007) 015
e±
νe
(−)
(A, Z) (A, Z ± 1)
Beta decay
e±
νe
(−)
Neutrino Capture on aBeta Decaying Nucleus
(A, Z) (A, Z ± 1)
This process has no energy threshold !
dn/dEe
Qβ
mν
Ee-me
2mν
A 2 mv gap in the electron spectrum centered around Qβ
Today we know that v are NOT degenerate but are massive !!
Beta decay
Neutrino Capture on aBeta Decaying Nucleus
dn/dEe
Ee-me
Qβ
mν
NCB Cross Sectiona new parametrization
Beta decay rate
NCB
The nuclear shape factors Cβ and Cν both depend on the same nuclearmatrix elements
It is convenient to define
In a large number of cases A can be evaluated in an exact way andNCB cross section depends only on Qβ and t1/2 (measurable)
NCB Cross Sectionon different types of decay transitions
• Superallowed transitions
• This is a very good approximation also for allowedtransitions since
• i-th unique forbidden
NCB Cross Section EvaluationThe case of Tritium
Using the expression
we obtain
where the error is due to Fermi and Gamow-Teller matrixelement uncertainties
Using shape factors ratio
where the error is due only to uncertainties on Qβ and t1/2
lim β → 0 =
lim β → 0=
NCB Cross Section Evaluation
allowed 1st unique forbidden 2nd unique forbidden 3rd unique forbidden
allowed 1st unique forbidden 2nd unique forbidden 3rd unique forbidden
β+ (bottom)β− (top) Qβ = 1 keV
Qβ = 100 keVQβ = 10 MeV
NCB Cross Section Evaluationusing measured values of Qβ and t1/2
1272 β− decays
799 β+ decays
Beta decaying nuclei having BR(β±) > 5 %selected from 14543 decays listed in the ENSDF database
3H
NCB Cross Section Evaluationspecific cases
Superallowed 0+ 0+ decaysused for CVC hypotesis testing(very precise measure of Qβ and t1/2) Nuclei having the highest product
σNCB t1/2
Relic Neutrino Detection
In the case of Tritium we estimate that 7.5 neutrino capture eventsper year are obtained using a total mass of 100 g
The cosmological relic neutrino capture rate is given by
Tν = 1.7 ⋅ 10-4 eV
after the integration over neutrino momentum and insertingnumerical values we obtain
Relic Neutrino Detectionsignal to background ratio
In the case of Tritium (and using nν=50) we found that
Taking into account the beta decays occurring in the last bin of width ∆at the spectum end-point we have that
The ratio between capture (λν) and beta decay rate (λβ) is obtainedusing the previous expressions
∼ 10- 10
Relic Neutrino Detectionsignal to background ratio
Observing the last energybins of width ∆
∆
It works for ∆<mv
dn/dTe ββ
mν Te
2mν
∆ ∆∆
where the last term is the probability for a beta decay electronat the endpoint to be measured beyond the 2mν gap
Relic Neutrino Detectiondiscovery potential
As an example, given a neutrino mass of 0.7 eV and anenergy resolution at the beta decay endpoint of 0.2 eVa signal to background ratio of 3 is obtained
In the case of 100 g mass target of Tritium it would takeone and a half year to observe a 5σ effect
In case of neutrino gravitational clustering we expect asignificant signal enhancement
FD = Fermi-Dirac NFW= Navarro,Frenk and WhiteMW=Milky Way (Ringwald, Wong)
KATRINKarlsruhe Tritium Neutrino Experiment
Aim at direct neutrino mass measurement through thestudy of the 3H endpoint(Qβ =18.59 keV, t1/2=12.32 years)
Phase I:Energy resolution: 0.93 eVTritium mass: ∼ 0.1 mgNoise level 10 mHzSensitivity to νe mass: 0.2 eV
Magnetic Adiabatic Collimator + Electrostatic filter
KATRINKarlsruhe Tritium Neutrino Experiment
MonteCarlo simulation of phase I data
First results in 2011End of Phase I data taking: 2015
Phase II:Energy resolution: 0.2 eVNoise level 1 mHz
MARE
Aim at direct neutrino mass measurement through thestudy of the 187Re endpoint (Qβ =2.66 keV, t1/2=4.3 x 1010 years)Using TEs+micro-bolometers @ 10 mK temperature
187Re crystal
TES
MARE
Energy resolution: 2÷3 eVTotal 187Re mass: ∼ 100 g
Phase II:Energy resolution: < 1 eV
vAP CollaborationCvB map 20??