Carlos Muñoz

Madrid, Spain

Dark Matter detection

Meeting on Fundamental CosmologySantander, 17-19 June 2015

Evidence for DM

Evidence for DM at very different scales, since 1930’s:

COBE, WMAP, Planck

Carlos Muñoz

IFT UAM-CSIC

Dark Matter 2

http://es.wikipedia.org/wiki/Archivo:WMAP.jpghttp://es.wikipedia.org/wiki/Archivo:WMAP.jpg

Carlos Muñoz

IFT UAM-CSIC

Dark Matter 3

Results from the Planck satellite,

Wbh2 0.022

WDM

h2 0.12

confirm that about 85% of the matter in the Universe is dark

WDE

h2 0.31

http://www.google.es/url?sa=i&rct=j&q=planck+results&source=images&cd=&cad=rja&docid=ssIUhldXVl-mTM&tbnid=J8QNwd9SqFBcBM:&ved=0CAUQjRw&url=http://blogs.discovermagazine.com/outthere/2013/03/22/four-surprises-in-plancks-new-map-of-the-cosmos/&ei=UdyPUeGZA4aG0AXisoHIBA&bvm=bv.46340616,d.ZGU&psig=AFQjCNFhrK95RyXfFg1f4FeagZfCjeXoLQ&ust=1368468918871780http://www.google.es/url?sa=i&rct=j&q=planck+results&source=images&cd=&cad=rja&docid=ssIUhldXVl-mTM&tbnid=J8QNwd9SqFBcBM:&ved=0CAUQjRw&url=http://blogs.discovermagazine.com/outthere/2013/03/22/four-surprises-in-plancks-new-map-of-the-cosmos/&ei=UdyPUeGZA4aG0AXisoHIBA&bvm=bv.46340616,d.ZGU&psig=AFQjCNFhrK95RyXfFg1f4FeagZfCjeXoLQ&ust=1368468918871780

Dark Matter 4

The only possible candidate for DM within the Standard Model of Particle Physics, the neutrino, is excluded

Its mass seems to be too small, m ~ eV to account for W DM h2 0.1

This kind of (hot) DM cannot reproduce correctly the observed structure in the Universe; galaxies would be too young

This is a clear indication that we need to go

beyond the standard model of particle physics

PARTICLE CANDIDATES

Carlos Muñoz

IFT UAM-CSIC

We need a new particle with the following properties:

Stable or long-lived

Neutral Otherwise it would bind to nuclei and would be excluded from unsuccessful searches for exotic heavy isotopes

Produced after the Big Bang and still present today

Reproduce the observed amount of dark matter W DM h2 0.1

Dark Matter

In the early Universe, at some temperaturethe annihilation rate of DM WIMPs droppedbelow the expansion rate

and their density has been the same since then, with:

Carlos Muñoz

IFT UAM-CSIC

h2WIMP

sann = sweak

3 x 10-27 cm3 s-1

sannv 0.1

WIMP

WIMP

f

f

W

A particle with weak interactions and a mass GeV-TeV, the so called WIMP (Weakly Interacting Massive Particle),is able to reproduce this number

3 x 10-26 cm3 s-1 sannv

thermal cross section

5

DETECTION

Carlos Muñoz IFT UAM-CSIC

Dark Matter 6

The LHC could detect a new kind of particle

If we are able to measure the mass and interactions of the new particle,

checking that W DM h2 0.1, this would be a great success…but how can we be sure it is stable on cosmological scales?

A complete confirmation can only arise from experimentswhere the particle is detectedas part of the galactic halo

This can come from direct DM searches

or indirect DM searches

Direct and Indirect Detection

7Dark Matter

gammasantimatterneutrinos

These three detection strategies are ideal because they allow exploring in a complete way many different particle dark matter models

Besides, in the case of a redundant detection (in two or more different experiments) the combination of their data can provide good insight into the nature of the dark matter

8Dark Matter Carlos Muñoz

IFT UAM-CSIC

Underground Labs and indirect detection DM experiments around the world 9

AMS

DIRECT DETECTION

r0 ~ 0.3 GeV/cm3

v0 ~ 220 km/s

J ~ r0 v0 /mWIMP~ 104 WIMPs /cm2 s

through elastic scattering with nuclei in a detector is possible

DAMA/LIBRA photo

For sWIMP-nucleon 10-8-10-6 pb a material with nuclei composed of about 100 nucleons, i.e. mN ~ 100 GeV

R ~ J sWIMP-nucleon/ mN 10-2 -1 events/kg day

EWIMP 1/2 (100 GeV/c2) (220 km/s)2 25 keV

energy produced by the recoiling nucleus can be measured through ionization, scintillation, heat few keV

Dark Matter 10Carlos Muñoz

IFT UAM-CSIC

convenient to have as muchmaterial as possible

DAMA experiment had 100 kg NaI crystals

e.g., DAMA only measures scintillation light Escintillation = Q ErecoilQ(quenching factor) = 0.3 for Na , 0.09 for I

Carlos Muñoz IFT UAM-CSIC

12

Annual modulation

DAMA/LIBRA250 kg NaI crystal scintillatorsat Gran Sasso.

It does not strongly discriminatebetween WIMP scatters and background events

Experiments must be located in the deep undergroundto greatly reduced the rate of these background events

WIMPs are expected to produce less or about 10-2 nuclear recoils/kg day with energies of few keV

But cosmic rays occur at >100 events/kg day with energies~ keV-MeV and generate muon-induced neutrons producingnuclear recoils similar to those expected for WIMPs

The background problem

13Dark Matter Carlos Muñoz

IFT UAM-CSIC

Combining two techniques of detection one can discriminate the electronrecoils from nuclear recoils: heat + ionization , heat + scintillation , scintillation + ionization

In addition, neutrons are also generated by theenvironmental radioactivity, but also rays and particlesare generated producing electron recoils

…everything above background might be a signal

DIRECT DARK MATTER EXPERIMENTS

Superheated

liquids(bubble)

Scintillation(light)

Ionization(charge)

Phonon(heat)

PICASSO (C4F10)SIMPLE (C2ClF5)COUPP (CF3I)/PICO

DAMA/LIBRA (NaI) XMASS (Xe)KIMS (CsI)ANAIS (NaI)KIMS (NaI)DM-Ice (NaI) DEAP3600 (Ar)MiniCLEAN (Ar)

XENON100 (Xe)ZEPLIN-III (Xe)LUX (Xe)LZ 7T (Xe)XENON1T (Xe)ArDM (Ar)DarkSide (Ar)CRESST (CaWO4)

EURECA (CaWO4)

CUORE (TeO2)

CDMS (Ge, Si )EDELWEISS-II (Ge)SuperCDMS (Ge)EURECA (Ge)

CoGeNT (Ge) CDEX (Ge)TEXONO (Ge)C-4 (Ge)DRIFT (CS2) DM-TPC (CF4)NEWAGE (CF4)MIMAC (3He/CF4)

PresentFuture DM hints

Clara Cuesta UZ Ph.D. Defense 2013 15

Carlos MuñozIFT UAM-CSIC

Dark Matter 20

LUX: active 250 kg of liquid Xe(scintillation + ionization)

Sanford underground lab. South Dakota

XENON100

LUX

CRESST-II

CoGeNT

CDMS II: 4.5 kg Ge+1.2 kg Si(ionization + heat)CDMS II

Figure from CDMS collab. 1504.0587

Soudan underground lab. Minnesota

But…what these results mean from the theoretical viewpoint?

10-4

pb

10-5

10-6

10-7

10-8

10-9

10-3

Crucial Moment for Supersymmetry in 2015: LHC Run II 13 TeV

The spectrum of elementary particles is doubled

with masses 1000 GeV

A rich phenomenology

Carlos MuñozIFT UAM-CSIC

Dark Matter 22

Neutralino in the MSSM (with R-parity conservation) is a WIMP

Supersymmetry

Dark Matter 24Carlos Muñoz

IFT UAM-CSIC

Generally small (1st, 2nd gen. squarks are heavy) Leading contribution (increases with Higgsino component)

Higgs exchangeSquark exchange

BS → µ+ µ− . Following the recent observat ional hints, we demand the presence of a Higgs

boson in the mass range 124− 127 GeV with SM-like decays []. Finally, some analysis suggest

the existence of a second singlet-like Higgs boson with a mass in the range 96 − 100 GeV

[DC: check]. We also explore this possibility in a number of benchmark points.

In Refs. [?, ?] we showed that the sneutrino mass could be easily adjusted to any value

by playing with the free parameters λN , AλN and mÑ without significant ly affect ing the

NMSSM phenomenology. For this reason, in this analysis we consider it a free parameter

within each NMSSM benchmark point .

2.1 Const raint s on t he H iggs invisible decay widt h

The recent ly discovered scalar part icle at the LHC is compat ible with a Higgs boson with a

mass of 126 GeV and SM-like branching rat ios [DC: citat ion needed]. Within the NMSSM

a scalar Higgs with these propert ies can be obtained in wide regions of the parameter space

[?,?,?,?,?,?,?,?,?,?,?,?,?,?,?]. In fact , the presence of an extra scalar Higgs field induces

new contribut ions to the Higgs mass from the λSHuHd term in the superpotent ial, which

allows to get a fairly heavy Higgs boson while reducing the fine-tuning with respect to the

situat ion in the MSSM. The Higgs sector of the NMSSM is very rich, and the presence of a

lighter scalar Higgs is also allowed, provided that it is most ly singlet-like

All these features are st ill valid in our construct ion, however, when implement ing con-

straints on the result ing Higgs phenomenology one has to be aware that the presence of light

RH neutrinos or sneutrinos can contribute significant ly to the invisible decay width of the

scalar Higgses [?]. This leads to stringent constraints on the parameter space, since the invis-

ible decay width of the SM-like Higgs is bound to be BR(h0SM → inv) 0.20− 0.65 [?,?,?,?].

The decay width of a scalar Higgs into a RH sneutrino pair or a RH neutrino pair is [?],

ΓH 0i →Ñ Ñ=

|CH 0i ν̃ ν̃|2

32πmH 0i

1−4m2ν̃m2

H 0i

1/ 2

, (2.9)

ΓH 0i →N N=

λ2N (S3H 0i

)2

32πmH 0i

1−4m2Nm2

H 0i

3/ 2

, (2.10)

where the Higgs-sneutrino-sneutrino coupling reads [?]

CH 0i ν̃ ν̃=

2λλN M W√

2gsinβS1

H 0i+ cosβS2

H 0i+ (4λ2N + 2κλN )vs + λN

AλN√2

(S3H 0i

)2 . (2.11)

In terms of these, the total invisible branching rat io reads

BR(h0SM → inv) =ΓH 0i →Ñ Ñ

+ ΓH 0i →N N

ΓN M SSM + ΓH 0i →Ñ Ñ+ ΓH 0i →N N

, (2.12)

5

Otherwise unconstrained from LHC Constrained by the results on

Also affected by mH=126 GeV

in the phenomenological MSSM (pMSSM)

with 19 independent parameters,

Ma , ma , Aa , tan β , µ,

one obtains

In view of the LHC constraints on SUSY, Higgs data, flavour physics observables,

Carlos MuñozIFT UAM-CSIC

Dark Matter 25

Figure from Mahmoudi, Arbey, 1411.2128

For the relic density, the upper bound is applied, allowing for thepossibility of multiple DM componentes (neutralinos + axions and/or other candidates)

h2WIMP

0.12W

Similar results for neutralinosor sneutrinos in the NMSSM are expected

h2WIMP

0.12WIf is imposed

Figure from Roszkowski, Sessolo, Williams, 1411.5214

Future experimentswill explore largeregions of theparameter space

- -- -- -- ---- -

-----

INDIRECT DETECTION

An excess of positrons for energies larger than 10 GeV has been detected by PAMELA (2008), Fermi-LAT (2010) and AMS (2013)

AMS

problems with the WIMP (~1 TeV) explanation:

Otherwise boost factors, ranging 102 - 104, provided by clumpiness in the DM distribution, are needed

Data implies σannv ~10–23 cm3 s–1 , but this

would produce

10 are not expected

Contributions of e– and e + from Monogem or Geminga pulsar or a sum of Milky Way pulsar population, assuming different distance, age and energetic of the pulsars.

Possible astrophysical explanations:

Super Nova Remnants

But conventional astrophysics in the galactic center is notwell understood. An excess might be due to the modelingof the diffuse emission, unresolved sources, etc.

an excess of gamma rays could be a signature of DM annihilations

An interesting possibility could be to search for DM around the Galactic Center where the density is very large

on behalf of the Fermi-LAT: Morselli, Vitale, 0912.3828 Morselli, Cañadas, Vitale 1012.2292 analized the inner galaxy region

Dark Matter 42Carlos Muñoz

IFT UAM-CSICDark Matter 42

particle physics astrophysics

Assuming an excess, and that the DM density in the inner galaxy is r(r) ~ r0/r ,

one can deduce possible DM examples reproducing the observations

Hooper, Goodenough, 1010.2751Hooper, Linden, 1110.0006Abazajian, Canac, Horiuchi, Kaplinghat, 1402.4090Daylan, Finkbeiner, Hooper, Linden et al., 1402.6703Calore, Cholis, Weniger, 1409.0042

1.1 - 1.3

Dark Matter 44

1.4 - 2.0 x 10-26 cm3 s-1 sannv

Carlos Muñoz

IFT UAM-CSIC

Dark Matter 44

The spectrum of the excess peaks at 1-3 GeV,and is well fit by 31-40 GeV DM particle annihilating to bb

-

Local Group dwarf spheroidal galaxies (dSph) are attractive targets because:

-they are nearby -largely dark matter dominated systems-relatively free from gamma-ray emission from other astrophysical sources

6-years of Fermi-LAT data. No excess from a combined analysis of 15 dSph1503.02641

Constraints lie below the canonical termal relic cross section for DM of mass < 100 GeV

annihilating via bb channel and +- channel~-

In general the final state will be a combination of the final states shown here

e.g., in SUSY, the neutralino annihilation modes are 70% bb - 30% for a Bino DM, and 100% W+W- for a Wino DM

Also, the value of sv in the Galactic halo might be smaller than 3 x10-26 cm3 s-1

Figure from Conrad, 1411.1925

Fermi 1001.4531

Quark channels

-e.g., in SUSY, in the early Universe coannihilationchannels can also contribute to sv

-Also, DM particles whose annihilation in the Early Universe is dominated by velocity dependent contributions would have a smaller value of sv in the Galactic halo, where the DM velocity is much smaller, and can escape this constraint:

Carlos Muñoz

IFT UAM-CSIC

47Dark Matter

The gravitino LSP also decays through the interactiongravitino-photon-photino (l)

due to the photino-neutrino mixingafter sneutrinos develop VEVs , opening the channel

Takayama, Yamaguchi, 2000

Nevertheless, it is supressed both by the Planck mass and the smallR-parity breaking, thus the lifetime of the gravitino can be longer

than the age of the Universe (1017 s)

~

B

g1

Gravitino as decaying dark matter

In models where R-parity is broken, the neutralino or the sneutrino with very short lifetimes cannot be used as candidates for (annihilating) DM

Thus, the gravitino (superWIMP) can be a good (decaying) DM candidate

FERMI might in principle detectthese gamma rays

Since the gravitino decays into a photon and neutrino, the former produces a gamma-ray line at energies equal to m3/2/2

SSM

Choi, López-Fogliani, C.M., Ruiz de Austri, 0906.3681

Carlos Muñoz

IFT UAM-CSIC

67Dark Matter

Lopez-Fogliani, C. M., PRL 97 (2006) 041801

As a consequence, values of the gravitino masslarger than about 10 GeV are disfavoured by Fermi LAT data

Neutrino content of the photino.

In the μνSSM in order to

reproduce neutrino data:

10-12

Search for 100 MeV to 10 GeV

γ-ray lines in the Fermi-LAT data

and implications for gravitino dark

matter in the μνSSM

69

More recently, together with Fermi-LAT collaborators we performed the following search:

arXiv:1406.3430 [astro-ph.HE], JCAP 10 (2014) 023

Category II paper:

-Fermi-LAT Collaboration: Albert, Bloom,

Charles, Gómez-Vargas, Mazziotta, Morselli

External authors: C. M., Grefe, Weniger

SSM

72SSM gravitinos with masses larger than 4.8 GeV

or lifetimes smaller than 7.9 x 1027 s are excluded as DM candidates

excluded region

SSM gravitinos with masses larger than 4.8 (2.4) GeV

or lifetimes smaller than 7.9 x 1027 (1.3 x 1028) s are excluded as DM candidates

Applying these boundsto our model:

Evidence for the existence of Dark Matter

CONCLUSIONS

-is overwhelming: galaxies, clusters, filaments, CMB, structure formation, …

-about 85% of the matter of the Universe is dark

Particle candidates for Dark Matter

-stable WIMPs like neutralino, sneutrino

decaying superWIMPs like gravitino

or Kaluza-Klein, scalar DM, fermion DM

or axion, …

Detection of the Dark Matter

-There are impressive experimental efforts by many collaborations around the world:

DAMA/LIBRA, CoGeNT, CRESST, CDMS, XENON, LUX,…, Fermi, PAMELA, AMS, …, MAGIC, HESS,…, IceCube, ANTARES,…

Thus the present experimental situation is very exciting

And, besides, the LHC is back