(some) Future CMB Constraints on fundamental physics

Alessandro Melchiorri Universita’ di Roma, “La Sapienza”

MIAMI2010, Fort Lauderdale December 15th 2010

Komatsu et al, 2010, 1001.4538

New WMAP results from 7 years of observations

How to get a bound on a cosmological parameter

DATA

Fiducial cosmological model:(Ωbh2 , Ωmh2 , h , ns , τ, Σmν )

PARAMETERESTIMATES

New Measurements, More Parameters !

• Neutrino masses

• Neutrino effective number

• Primordial Helium

m

effN

PY

Small scale CMB can probe Helium abundance at recombination.

See e.g., K. Ichikawa et al., Phys.Rev.D78:043509,2008R. Trotta, S. H. Hansen, Phys.Rev. D69 (2004) 023509

Komatsu et al, 2010, 1001.4538

Cosmological (Active) NeutrinosNeutrinos are in equilibrium with the primeval plasma through weak interaction reactions. They decouple from the plasma at a temperature

MeVTdec 1We then have today a Cosmological Neutrino Background at a temperature:

eVkTKTT 43/1

1068.1945.111

4

With a density of:

33,

32

1121827.0)3(

4

3 cmTnTgnkkfff

That, for a massive neutrino translates in:

eV

mh

eV

m

h

mnk

kk

c

kk

kk

5.925.92

1 22

,

Normal hierarchy Inverted hierarchy

If neutrino masses are hierarchical then oscillation experimentsdo not give information on the absolute value of neutrino masses

Moreover neutrino masses can also be degenerate

catmospheri321 ,, mmmm

SOLAR nKAMLAND

ATMO. nK2K

123 mmm 312 mmm

Testing the neutrino hierarchy

Inverted Hierarchy predicts:

∑𝑚𝑣>0.10𝑒𝑉Normal Hierarchy predicts:

∑𝑚𝑣>0.05𝑒𝑉

Degenerate Hierarchy predicts:

∑𝑚𝑣>0.15𝑒𝑉

we assume 𝑚❑2=0.0025𝑒𝑉 2

Current constraints on neutrino mass from Cosmology (Fogli et al, 2010 in preparation).

Blue: WMAP-7Red: w7+SN+Bao+H0Green: w7+CMBsuborb+SN+LRG+H0

See also:M. C. Gonzalez-Garcia, Michele Maltoni, Jordi Salvado, arXiv:1006.3795Toyokazu Sekiguchi, Kazuhide Ichikawa, Tomo Takahashi, Lincoln Greenhill, arXiv:0911.0976Extreme (sub 0.3 eV limits):F. De Bernardis et al, Phys.Rev.D78:083535,2008, Thomas et al. Phys. Rev. Lett. 105, 031301 (2010)

[eV]

Current constraints (assuming LCDM):

Smn<1.3 [eV] CMB (but see Maria’s talk)

Smn<0.7-0.5 [eV] CMB+other

Smn<0.3 [eV] CMB+LSS (extreme)

Blue: WMAP-7Red: w7+SN+Bao+H0Green: w7+CMBsuborb+SN+LRG+H0

Current constraints on neutrino mass from Cosmology (Fogli et al, 2010 in preparation).

Constraints weaken by 30-50%when «dark energy» is included.

Komatsu et al, 2010, 1001.4538

Neutrino background.Changes early ISW.Hint for N>3 ?

Gianpiero Mangano, Alessandro Melchiorri, Olga Mena, Gennaro Miele, Anze SlosarJournal-ref: JCAP0703:006,2007

J. Hamann et al, arXiv:1006.5276

3 Active massless neutrinos+Ns massive neutrinos

3 Active massive neutrinos +Ns massless neutrinos

Latest results from ACT, Dunkley et al. 2010 𝑁𝑒𝑓𝑓 =5.3±1.3

PlanckSatellite launch14/5/2009

Planck First Light Survey (September 2009). Experiment is working as expected

Blue: current dataRed: Planck

Galli, Martinelli, Melchiorri, Pagano, Sherwin, Spergel, PRD submitted, arXiv:1005.3808 2010

Let’s consider not only Planck but alsoACTpol (From Atacama Cosmology Telescope,Ground based, results expected by 2013)CMBpol (Next CMB satellite, 2020 ?)

Galli, Martinelli, Melchiorri, Pagano, Sherwin, Spergel, PRD submitted, arXiv:1005.3808 2010

Blue: Planck DYp=0.01

Red: Planck+ACTpol DYp=0.006

Green: CMBPol DYp=0.003

Constraints on Helium Abundance

Galli, Martinelli, Melchiorri, Pagano, Sherwin, Spergel, PRD submitted, arXiv:1005.3808 2010

Constraints on Neutrino Number

Blue: Planck DNn=0.18

Red: Planck+ACTpol DNn=0.11

Green: CMBPol DNn=0.044

Galli, Martinelli, Melchiorri, Pagano, Sherwin, Spergel, PRD submitted, arXiv:1005.3808 2010

Constraints on Neutrino Mass

Blue: Planck DSmn=0.16

Red: Planck+ACTpol DSmn=0.08

Green: CMBPol DSmn=0.05

Testing the neutrino hierarchy

Inverted Hierarchy predicts:

∑𝑚𝑛>0.10𝑒𝑉Normal Hierarchy predicts:

∑𝑚𝑛>0.05𝑒𝑉

Degenerate Hierarchy predicts:

∑𝑚𝑛>0.15𝑒𝑉

we assume 𝑚❑2=0.0025𝑒𝑉 2

Constraints on Neutrino Masses from CMB

[eV]

Black: Planck

Red: Planck+New exp. 1000 bol.

Blue: Planck+New exp. 5000 bol.

Limits at 95% c.l.:

Combining a new CMB experiment to Planck coud improve the bounds on the neutrinomass by a factor 3. This would:Falsify Degenerate Hierarchy and Probe the Inverted Hierarchy

Constraints on Neutrino Masses from CMB+Priors

Red: 1000 riv+ Prior 1% H0+ Priori 2% Wm

Blue: 1000 riv+ Prior 1% H0+ Priori 2% Wm

Red Dashed: 1000 riv+ Prior 0.5% H0+ Priori 1% Wm

Blue Dashed: 1000 riv+ Prior 0.5% H0+ Priori 1% Wm

Limits at 95% c.l.:

∑𝑚𝑛<0.057 𝑒𝑉

∑𝑚𝑛<0.054 𝑒𝑉

∑𝑚𝑛<0.040𝑒𝑉

∑𝑚𝑛<0.035𝑒𝑉With external priors on the Hubble parameterAnd the matter density also the NormalHierarchy can be probed: safe detection ofa neutrino mass.

• Recent CMB measurements fully confirm L-CDM. • With future measurements constraints on new parameters related to laboratoryPhysics could be achieved.

In 2012 from Planck we will know:

- If the total neutrino mass is less than 0.5eV.- If there is an extra background of relativistic particles.- Helium abundance with 0.01 accuracy.

CONCLUSIONS