8/6/2019 Dark Matter Searches Dark Matter Searches
1/74
Dark Matter SearchesDark Matter Searches
Katherine FreeseMichigan Center for Theoretical Physics
University of Michigan
8/6/2019 Dark Matter Searches Dark Matter Searches
2/74
8/6/2019 Dark Matter Searches Dark Matter Searches
3/74
Vera RubinVera Rubin
Studied rotation curves
of galaxies, and found
that they are FLAT
8/6/2019 Dark Matter Searches Dark Matter Searches
4/74
95% of the matter in galaxies is95% of the matter in galaxies is
unknown dark matterunknown dark matter Rotation Curves of Galaxies:Rotation Curves of Galaxies:
EXPECTED
FROM STARS
OBSERVED:FLAT ROTATION
CURVE
8/6/2019 Dark Matter Searches Dark Matter Searches
5/74
Good news: cosmologists
don't need to "invent" newparticle:
Weakly Interacting
Massive Particles
(WIMPS). e.g.,neutralinos
Axions
ma~10-(3-6) eV
arises in Peccei-Quinn
solution to strong-CP
problem
8/6/2019 Dark Matter Searches Dark Matter Searches
6/74
THE BEGINNINGS OF
DARK MATTERPARTICLE
PHENOMENOLOGY
8/6/2019 Dark Matter Searches Dark Matter Searches
7/74
Axion detector
(axion to photon conversion)
Pierre Sikivie
PRL 51 (1983) p. 1415
8/6/2019 Dark Matter Searches Dark Matter Searches
8/74
Axion masses
8/6/2019 Dark Matter Searches Dark Matter Searches
9/74
Overall status of axion bounds
8/6/2019 Dark Matter Searches Dark Matter Searches
10/74
The WIMP Miracle
Weakly Interacting Massive Particles are the bestmotivated dark matter candidates, e.g.: LightestSupersymmetric Particles (such as neutralino) are theirown antipartners. Annihilation rate in the early universe
determines the density today. The annihilation rate comes purely from particle physicsand automatically gives the right answer for the relicdensity!
This is the mass fraction of WIMPs today, and givesthe right answer (23%) if the dark matter is weakly
interacting
h2
=
31027
cm3/sec
ann
WIMP mass: GeV 10 TeV
8/6/2019 Dark Matter Searches Dark Matter Searches
11/74
WIMP Dark Matter
Phenomenology: History Looking for neutrinos (Drukier and Stodolsky)
First paper suggesting direct detection: Goodman and
Witten 1986 Second paper on direct detection: we
(I) took into account WIMP distribution in galaxy and (ii)suggested annual modulation (Drukier, Freese, and
Spergel 1986). A followup paper (Freese, Frieman, Gould 1988)
suggested using annual modulation to pull out signalfrom background. This is how the only current claimfor direct detection was done (DAMA experiment).
8/6/2019 Dark Matter Searches Dark Matter Searches
12/74
Drukier and Stodolsky
(1984)proposed MeV neutrino detection via elasticscattering off nuclei with 100 eV recoil energy
Andrzej
Drukier
Leo Stodolsky
8/6/2019 Dark Matter Searches Dark Matter Searches
13/74
GOODMAN AND WITTEN (1986)
turned same approach to DMdetection
8/6/2019 Dark Matter Searches Dark Matter Searches
14/74
Drukier, Freese, & Spergel (1986)
i) included model for galactic halo,
ii) proposed annual modulation, iii)
SI/SD for various detector elements
8/6/2019 Dark Matter Searches Dark Matter Searches
15/74
8/6/2019 Dark Matter Searches Dark Matter Searches
16/74
EXCITING TIMES
We made WIMP proposals twenty years
ago:
It is coming to fruition!
My personal prediction: one of the
anomalous results is right and we will
know very soon.
8/6/2019 Dark Matter Searches Dark Matter Searches
17/74
LHC-Making DM
Coming Soon(We hope)
8/6/2019 Dark Matter Searches Dark Matter Searches
18/74
Supersymmetric Particles in LHC Signature: missing energy when SUSY particle is
created and some energy leaves the detector
Problem with identification: degeneracy ofinterpretation
SUSY can be found, but, you still dont know howlong the particle lives: fractions of a second to leavedetector or the age of the universe if it is dark matter
Proof that the dark matter has been found requiresastrophysical particles to be found
8/6/2019 Dark Matter Searches Dark Matter Searches
19/74
Direct Detection of WIMP dark
matterA WIMP in the Galaxy
travels through our
detectors. It hits a
nucleus, and depositsa tiny amount of
energy. The nucleus
recoils, and we detect
this energy deposit.
Expected Rate: less than one count/kg/day!
8/6/2019 Dark Matter Searches Dark Matter Searches
20/74
Event rate
dR
dE
=
NT
MT
d
dE
nv f(v, t)d3v
(number of events)/(kg of detector)/(keV of recoil energy)
=
0F2 (q)
2m2
f(v, t)
vd
3v
v> ME/ 22
Spin-independent
Spin-dependent
0=A22
p2
p
0=4
2
Sp
Gp + Sn Gn
2
8/6/2019 Dark Matter Searches Dark Matter Searches
21/74
From DM Tools Website
8/6/2019 Dark Matter Searches Dark Matter Searches
22/74
Many claims/hints of WIMPdark matter detection: how
can we be sure?
1) The DAMA annual modulation
2) The HEAT, PAMELA, and ATIC positronexcess
3) Gamma-rays from Galactic Center 4) WMAP Haze
HAS DARK MATTER BEENDISCOVERED?
8/6/2019 Dark Matter Searches Dark Matter Searches
23/74
The DAMA
AnnualModulation
8/6/2019 Dark Matter Searches Dark Matter Searches
24/74
DAMA annual modulationDrukier, Freese, and Spergel (PRD 1986);Freese, Frieman, and Gould (PRD 1988)
Data do show a 8 modulation
WIMP interpretation???
Bernabei et al 2003
8/6/2019 Dark Matter Searches Dark Matter Searches
25/74
DAMA/LIBRA
(April 17,2008)
8 sigma
8/6/2019 Dark Matter Searches Dark Matter Searches
26/74
Can the positive signal in DAMA
be compatible with null resultsfrom other experiments?
Savage, Gelmini, Gondolo, and Freese, arxiv:0808:3607(see also papers by Hooper and Zurek; Fairbairn and Schwetz;
Chang, Pierce and Weiner 2008)
8/6/2019 Dark Matter Searches Dark Matter Searches
27/74
Small remaining region at 10 GeV WIMP mass
DAMA: spin independent?
DAMA
XENON
CDMS
8/6/2019 Dark Matter Searches Dark Matter Searches
28/74
DAMA and
Spin-
dependent
cross sections
Savage, Gelmini,
Gondolo, Freese
0808:3607
Remaining window
around 10 GeV.
Removing SuperK:
WIMP mass
up to 20 GeV
allowed
DAMA
SUPER-K
XENON
CDMS
Hooper and Zurek extended Super-K bounds
8/6/2019 Dark Matter Searches Dark Matter Searches
29/74
New measurements of Suns
velocity relative to Halo:250 km/sec (not 220 km/sec)
All curves movethe left:
Remaining
window moves to
7-8 GeV at 3
sigma (5-15 for
SD)
CRESST
Savage, Freese, Gondolo, Spolyar 2009
8/6/2019 Dark Matter Searches Dark Matter Searches
30/74
Low mass window: COUPP,KIMS,
COGENT, PICASSO, CRESST
COUPP
8/6/2019 Dark Matter Searches Dark Matter Searches
31/74
COUPP bounds (2007)COUPP bounds (2007)
8/6/2019 Dark Matter Searches Dark Matter Searches
32/74
Preview of UC talks:Preview of UC talks:
COUPP (Eric Dahl, Friday) CoGeNT (Juan Collar, Friday)
Demonstration of acoustic discrimination.
Elimination of wall events. Commissioning of COUPP-60 kg.Commissioning of COUPP-60 kg. New spin-dependent limits (4 kg chamber).New spin-dependent limits (4 kg chamber).
Demonstration of surface event rejection.
First results from runs in Soudan. Prospects forProspects for PPCsPPCs in DM detection and beyond.in DM detection and beyond.
8/6/2019 Dark Matter Searches Dark Matter Searches
33/74
To reconcile DAMA with null
results from other experiements: Popular theory:
8/6/2019 Dark Matter Searches Dark Matter Searches
34/74
To reconcile DAMA with null
results of other experiments: Popular theory:
8/6/2019 Dark Matter Searches Dark Matter Searches
35/74
Direct Detection
In past two years, two orders of magnitudeincrease in sensitivity (the following results not
included in our compatibility study):
(i) CDMS
(ii) XENON-10
(iii) ZEPLIN III
New technology: liquid noble gases
XENON, LUX, XMASS
WARP (argon)
DEAPCLEAN (argon and neon)
8/6/2019 Dark Matter Searches Dark Matter Searches
36/74
ZEPLIN III (in Boulby mine)
Pink: XENON 10
Black: Zeplin IIIBlue: CDMS II
See talk of N. Smith
Future: ZEPLIN and LUX will join forces in DUSEL
(August 2009
First science run)
Second science
Run to begin
soon weeks
8/6/2019 Dark Matter Searches Dark Matter Searches
37/74
8/6/2019 Dark Matter Searches Dark Matter Searches
38/74
Electron recoils
Nuclear Recoils
8/6/2019 Dark Matter Searches Dark Matter Searches
39/74
n.b. if include 2008 data, this significance drops
8/6/2019 Dark Matter Searches Dark Matter Searches
40/74
CDMS bounds
Inelastic Dark Matter
8/6/2019 Dark Matter Searches Dark Matter Searches
41/74
Direct Detection In past two years, two orders of magnitude
increase in sensitivity:
(i) CDMS(ii) XENON-10
(iii) ZEPLIN II and III
New technology: liquid noble gasesXENON, LUX, XMASS
WARP (argon)
DEAPCLEAN (argon and neon)
8/6/2019 Dark Matter Searches Dark Matter Searches
42/74
EurekaMAX, GeoDM
DEAP/
Miniclean
8/6/2019 Dark Matter Searches Dark Matter Searches
43/74
8/6/2019 Dark Matter Searches Dark Matter Searches
44/74
Slide from Pearl Sandick
8/6/2019 Dark Matter Searches Dark Matter Searches
45/74
CRESST II
See talk by Leo Stodolsky
Scintillation
Plus phonons
8/6/2019 Dark Matter Searches Dark Matter Searches
46/74
8/6/2019 Dark Matter Searches Dark Matter Searches
47/74
8/6/2019 Dark Matter Searches Dark Matter Searches
48/74
8/6/2019 Dark Matter Searches Dark Matter Searches
49/74
RED OVALS: THOSE EXPTS THAT ARE CURRENTLY UNDERGROUND
8/6/2019 Dark Matter Searches Dark Matter Searches
50/74
Slide from Elena Aprile
8/6/2019 Dark Matter Searches Dark Matter Searches
51/74
Slide from Elena Aprile
8/6/2019 Dark Matter Searches Dark Matter Searches
52/74
LUX experiment, Homestake mine
LUX (DUSEL)
8/6/2019 Dark Matter Searches Dark Matter Searches
53/74
8/6/2019 Dark Matter Searches Dark Matter Searches
54/74
XENON,LZ,MAX,GEODM
EUREKA,DARWIN
Ultimate Searches?
8/6/2019 Dark Matter Searches Dark Matter Searches
55/74
The HEAT and
PAMELA PositronExcess
8/6/2019 Dark Matter Searches Dark Matter Searches
56/74
The Indirect Detection of Dark Matter
1. WIMP Annihilation
Typical final states include heavy
fermions, gauge or Higgs bosons
2.Fragmentation/DecayAnnihilation products decay and/or
fragment into combinations ofelectrons, protons, deuterium,
neutrinos and gamma-rays
3.Synchrotron and Inverse Compton
Relativistic electrons up-scatterstarlight/CMB to MeV-GeV energies,
and emit synchrotron photons via
interactions with magnetic fields
W+
W-
e+ q
q
p
0
e+
8/6/2019 Dark Matter Searches Dark Matter Searches
57/74
Annihilation Products 1/3 electron/positrons
1/3 gamma rays
1/3 neutrinos
Typical particles have energies roughly
1/10 of the initial WIMP mass
All of these are detectable!
8/6/2019 Dark Matter Searches Dark Matter Searches
58/74
Indirect Detection History Indirect Detection (Neutrinos)
Sun (Silk,Olive,Srednicki 85)
Earth (Freese 86; Krauss, Srednicki, Wilczek 86)
Indirect Detection (Gamma Rays, positrons) Milky Way Halo (Ellis, KF et al 87)
Galactic Center (Gondolo and Silk 2000)
Anomalous signals seen in HEAT (e+), HESS,
CANGAROO, WMAP, EGRET, PAMELA.
8/6/2019 Dark Matter Searches Dark Matter Searches
59/74
New Indirect Detection Results!
Dan Hooper - Direct and Indirect
Searches For Particle Dark Matter
(When it rains it pours)PamelaIceCube
FERMI
NEWMEAS
UREM
ENT!
NEWLI
MIT!
FIRSTLIG
HT
8/6/2019 Dark Matter Searches Dark Matter Searches
60/74
Positron excess HEAT balloon found anomaly in
cosmic ray positron flux
Explanation 1: dark matter
annihilation Explanation 2: we do not
understand cosmic ray
propagation
Baltz, Edsjo, Freese, Gondolo 2001
8/6/2019 Dark Matter Searches Dark Matter Searches
61/74
PAMELA EXCESS OF POSITRONS
8/6/2019 Dark Matter Searches Dark Matter Searches
62/74
Inspiration from our speaker
M. Boezio
ICECUBE/DEEPCORE will
8/6/2019 Dark Matter Searches Dark Matter Searches
63/74
ICECUBE/DEEPCORE will
see neutrinos in five years if
PAMELA anomaly is from DMSpolyar,
Buckley,
Freese,
Hooper,Murayama
2009
String of phototubes in
ice at South Pole
8/6/2019 Dark Matter Searches Dark Matter Searches
64/74
Gamma-rays from
the GalacticCenter
8/6/2019 Dark Matter Searches Dark Matter Searches
65/74
8/6/2019 Dark Matter Searches Dark Matter Searches
66/74
HESS Gamma-ray DataAharonian et al 2004
8/6/2019 Dark Matter Searches Dark Matter Searches
67/74
FERMI satellite
Launched June
2008
TALK OF
ELLIOTT BLOOM
NASA/DOE
gamma-ray
telescope
Dobler Finkbeiner Cholis Slatyer Weiner 2009
8/6/2019 Dark Matter Searches Dark Matter Searches
68/74
I. FERMI HAZE: controversial
(gamma rays from Galactic Center)
Dobler, Finkbeiner,Cholis, Slatyer, Weiner 2009
II. See also talk of Dan Hooper for yet another hint of DM
8/6/2019 Dark Matter Searches Dark Matter Searches
69/74
WMAP microwave emission
interpreted as dark matterannihilation in inner galaxy?
Finkbeiner 2005; Hooper,
Dobler 2007
Consistent with 100 GeV WIMPs.
WMAP HAZE
8/6/2019 Dark Matter Searches Dark Matter Searches
70/74
Possible evidence for WIMP
detection already now:
The DAMA annual modulation
The HEAT/PAMELA positron excess
Gamma-rays from Galactic Center
WMAP haze
Theorists are looking for models in whichthese results are consistent with one another(given an interpretation in terms of WIMPs)
8/6/2019 Dark Matter Searches Dark Matter Searches
71/74
Upcoming Data: will the Dark
Matter be found in 2010? LHC (find SUSY)
Indirect Detection due to annihilation:
FERMI (gamma rays)
PAMELA (positrons)
ICECUBE (neutrinos)
GAPS (antideuterons)
Direct Detection: many experiments
Directional Detection: see talk of D. Snowden-Ifft
8/6/2019 Dark Matter Searches Dark Matter Searches
72/74
What will it take for us to
believe DM has been found? I. Direct detection:
compatible signals in a variety of
experiments made of different detectormaterials, and all the parties agree
2. Indirect detection:
annihilation signals in a variety ofchannels (neutrinos, gamma-rays, etc)
all coming from the same source
8/6/2019 Dark Matter Searches Dark Matter Searches
73/74
Sagittarius streamDirectional detection with DRIFT-II
Freese, Gondolo, Newberg 2003
8/6/2019 Dark Matter Searches Dark Matter Searches
74/74
THE END