Rocky Kolb LPC 2 March 2016 Why You Should Care About Dark Matter …it’s most of the mass in the Universe (kind of important) Radiation: Chemical Elements: 0.005% (other than H & He) 0.025%
Neutrinos: ne 0.17% nm nt Stars: 0.8%
H & He: gas 4%
WIMP? Dark Matter: 25%
L? Dark Energy: 70% Why You Should Care About Dark Matter … the dinosaurs didn’t care, and look what happened to them! Far Future of Dark Matter
• Particle Physics: Understand the nature of dark matter (DM) and how it is embedded into a deeper theoretical framework: • If DM is a particle, want to know more than just mass, spin, and couplings, want to know how it fits into a model or theory • Want to know why DM exists • Want to understand its contribution to the mass budget
• Astrophysics: Understand the role of DM in the evolution of the universe and structure formation: • Is the DM completely cold? • Is there only one DM component? • Does DM have interactions that affect structure formation? Eight Decades of Dark Matter
Oort 1932 Local Neighborhood a Little Dim (M/L) ~ 2-3 Zwicky 1937 Galaxy Clusters Really Dark (M/L) ~ 500
Rubin & Ford 1970s Individual Galaxy Halos Also Dark (M/L) ~ 60
Dwarf Observers 1990s Dwarfs Really, Really Dark (M/L) ~ 3000
Coma Cluster
Fritz Zwicky Vladimir Lenin 1916
While at ETH Zwicky lived in Spiegelgasse 17 Varna, Bulgaria Zurich, Switzerland
Image: Jim Misti observed
luminous disk
cluster dynamics galactic rotation curves dwarf galaxies
gravitational lensing nucleosynthesis cluster gas in x-rays
background radiation structure formation cluster collisions Astronomy Contributions to Dark Matter
1. It exists!!! Thank you astronomy! 2. What is the local DM phase-space velocity distribution?
3. What is the local value of rDM ? 4. Are there nearby DM subclumps? 5. What is the background for g -ray emission from the galactic center? very near the galactic center?
6. What is rDM (r) in dwarf spheroidals? in DM subclumps? 7. Is DM multi-component like visible matter? 8. Does DM have self-interactions? 9. Does DM have normal gravitational interactions?
(a complete theory containing dark matter could answer the last three) Dark Matter
• Einstein or Newton didn’t have the last word Modified Gravity MOND (Modified Newtonian Dynamics, i.e., F ≠ m a)
• Rocky Rogue Planets
• Mass Challenged Stars Massive Compact Halo Objects (MACHOs) • Black Holes
• Unknown Particle Species Known Particle Species
Quarks Antiquarks Force Carriers
up down photon gluon W Z graviton
top bottom and now the HIGGS! strange charmDark particle must be “Beyond the Standard Model” (BSM) Leptons Antileptons electron electron neutrino
muon muon neutrino
tau tau neutrino Image: CERN
Dark particle must be stable and massive and interact weakly
Some Possible Origins of Dark Matter
Cosmological Phase Transitions (axions, mass ca. 10-15 GeV) Asymmetric Relics (name needed, mass ca. 6 GeV) Cold Thermal Relics (WIMPs, mass ca. 102 GeV) Gravitational (Inflation) Production (WIMPZILLAs, mass ca. 1012 GeV)
WIMPZILLA vs. KING WIMP KONG Particle Dark Matter Bestiary
• (sub-) eV mass neutrinos (WIMPs exist!) (hot) • sterile neutrinos, gravitini (warm) thermal relics, or decay of or oscillation from • lightest supersymmetric particle (cold) thermal relics • lightest Kaluza-Klein particle (cold) • Bose-Einstein condensates • axions, axion miniclusters from phase transitions • solitons (Q-balls, B-balls, …) nonthermal relics • supermassive WIMPZILLAs from inflation
Mass Interaction Strength 10-22 eV (10-56 g) Bose-Einstein only gravitational: WIMPZILLAs -8 +25 10 Mʘ (10 g) axion miniclusters strongly interacting: B balls * An objectof particular veneration. Relative abundance 10 10 10 10 - - - - 20 15 10 1 5 1 equilibrium equilibrium Cold e Thermal Relics e - 10 - M / T M / M / T M / 1 M / T d 10 ecreasing ecreasing abundance 2 increasing increasing * s A 10 3 Ben Lee (1935 — June 1977)
Steve Weinberg Model: 4-G Heavy Neutrino (GeV mass) with annihilation cross-section
Motivated by an incorrect FNAL experimental result (high-y anomaly) Model − effective field theory − excluded by direct detection LEP n counting NR annihilation cross section 휎v = × Møller flux thermal average
10-36 cm2 Wh2 0.11 sv Not quite so clean: • velocity dependence • resonances • co-annihilation • log dependence on M • decay production • spin-dependence • asymmetries • …
a 2 s = 10-36 cm2 = (150 GeV) 2
weak scale! DM Has “Weak-Scale” Interactions Weakly-Interacting Massive Particle: A WIMP! Michael Turner (actual size)
If I have seen further, it is by sitting on the shoulders…. The WIMP “Miracle”
mir·a·cle \ˈmir-i-kəl \ noun … often used to give an impression of great and unusual value in a trivial context …
1 : an extraordinary event manifestingI think you should be more divine intervention in humanexplicit affairs here in step two WIMPs Interact with SM Particles Indirect Detection
Relic Abundance STANDARD-MODEL WIMP PARTICLE
2 Direct Wh Detection
STANDARD-MODEL WIMP PARTICLE Collider Production WIMPs: Social or Maverick Species?
Social WIMP Maverick WIMP
Friended by many like-mass particles Not friended by any new particles Pals around with new un-WIMPy particles Any un-WIMPy pals beyond reach Part of a larger theoretical framework Theory framework: Don’t ask/Don’t tell Top down Bottom up Generally UV complete Not UV complete: Effective Field Theory Find the WIMP by finding its friends Find the WIMP through what is not seen Example: SUSY Example: Neutrinos before late 1960s upersymmetry & Socialist WIMPs
Superpartners Particles Developed in the early 70’s % quarks u d s squarks u%% d s Every known particle has an leptons e mt sleptons e%% mt % undiscovered superpartner. photon g photino g% Superpartners are massive.
W, Z W Z wino, zino W% Z% Lightest superpartner should gluon g gluonino g% be stable! graviton G gravitino G% In many realizations, lightest superpartner is weakly + Higgs h H A H Higgsinos h% H%% A% H + interacting.
Lightest Supersymmetric Particle is a candidate WIMP SWIMPs gravitinos, sneutrinos, axinos, … neutralinos Lightest neutralino: linear combination of SUSY partners of g, Z, and 2 Higgs bosons • Mass and gaugino/Higgsino fractions depend on about 100 SUSY parameters • Reduce to a manageable number of parameters (pMSSM, CMSSM, mSUGRA, …) • Many processes/diagrams contribute to annihilation into many channels − W+W -, ZZ, Zh, ZH, ZA, W+H -, HH, Hh, AA, hh, Ah, AH, f f − annihilation into f f proportional to fermion mass − no two-body final state with a photon (at lowest order) • LHC & other experiments have pushed SUSY scale high, usually too large Wh2,
unless some chicanery increases sA : “Focus Point” SUSY Resonant Annihilation Coannihilation
c SM c t neutralino has t large Higgsino A component
c SM t~ g mA 2 mc mmtc% =+e SWIMPs gravitinos, sneutrinos, axinos, … neutralinos Lightest neutralino: linear combination of SUSY partners of g, Z, and 2 Higgs bosons • Choose a model framework to reduce from about 100 SUSY parameters • Require consistent low-energy model − with neutralino DM candidate − that satisfies all experimental constraints • Low-energy annihilation cross section depends on neutralino composition, mass, and coupling and possibly other masses; all of these depend on about 100 SUSY parameters 2 • Generally sA v = a + b v ( velocity-independent part plus velocity-suppressed part) SUSY DM phenomenology very interesting and very rich.
SUSY/DM Relationship: Maverick Effective Field Theory (EFT)
• WIMP is the only state accessible to experiments: other states too massive (Maverick) c q Y g g • Many theories have common low-energy behavior when mediating particles are heavy compared to c q energies involved MEY ? c
• EFT not as desirable as a UV-complete theory: – can miss relations between quantities 2 – can’t describe high-energy behavior - 2 g L= (possibly like LHC) M 2 c Y q
• One example (DM fermionic & couples to quarks)
-2 = L c G1 c q G2 q G1 G2 c q -3 = mq L c G1 c q G2 q Minimal Flavor Violation G1 G2 Maverick WIMPs DM SM
Wh2 L (M) G1 G2
DM SM 2 EFT sA v = a + b v 2 operator WDM: v 1/20
cc q q v2 suppressed cc qg 5q v2 suppressed cg 5c q q unsuppressed cg 5c qg 5q unsuppressed m cg c qgm q unsuppressed m cg c qgm5 q unsuppressed m5 2 If WIMP cg c qgm q v suppressed* m5 2 Majorana cg c qgm5 q v suppressed* mn fermion cg c qgmn q unsuppressed mn5 cg c qgmn q unsuppressed Direct Detection Direct Detection Vogelsberger et al. • f (v) local WIMP phase-space density -3 − Assume: rDM = 0.4 GeV cm (subclumps, streams,…?) − Assume: Maxwellian velocity distribution v2 1/2 = 220 km s-1
• Spin dependent or independent? mm22 8 c N 2 Kopp et al. s c N (axial)=2 LJJ( + 1)
p mm+ )
( c N ) p
f
=
n f • Same coupling to p and n? (
s
/ )
22 p mm 2 f 1 c N /
éùn s (scalar)=(A - Z) f + Z f f c Np 2 ëûêú n p ( (mmc + N ) s WIMP Direct Detection
nuclear dR 1 r WIMP 3 ds (v) NUCLEUS 퐸푅 = ò dfv v( v) dERR MNucleus M WIMP dE (v) recoil vMIN
Recoil energies few to few dozen keV WIMP
r M Astrophysics: WIMP Particle physics: WIMP f (v) 푑휎/푑퐸푅
Detector Mass
Nuclear Target(s) (MNucleus and JNucleus) Experiment: 2 2 EThreshold = 2mcN vMIN / MNucleus
푑휎/푑퐸푅 Direct Detection Nuclear Recoil Signal SUPERHEATED BUBBLES COUPP, PICASSO, IONIZATION PICO CoGeNT, CDMSlite, TEXANO, CDEX MALBEK
CDMS, XENON, LUX, Edelweiss DarkSide, ZEPLIN
PHONONS LIGHT CRESST
DAMA/LIBRA, KIMS, CUORE ANAIAS, SABRE
After Jodi Cooley Direct Detection Direct Detection PICO COUPP CDMS
Xenon CoGeNT ( + EDELWEISS, DAMA, EURECA, ZEPLIN, DEAP, ArDM, WARP, LUX, SIMPLE, PICASSO, DMTPC, DRIFT, KIMS, LUX, ARDM, ANAIS, CDEX PandaX, DarkSide, DAMA/LIBRA …) Maverick WIMPs DM SM Wh2 L (M) G1 G2
sS (M) DM SM 2 EFT sS = c + d ( v + Q ) operator spin-independent/-dependent
cc q q spin independent cc qg 5q v2, Q2 suppressed cg 5c q q v2, Q2 suppressed cg 5c qg 5q (v2, Q2)2 suppressed m cg c qgm q spin independent m 2 2 cg c qgm5 q v , Q suppressed m5 2 2 cg c qgm q v , Q suppressed m5 cg c qgm5 q spin dependent mn cg c qgmn q spin dependent mn5 2 2 cg c qgmn q v , Q suppressed Direct Detection
From quark operators to scattering cross sections on nucleons: e.g., N() k+ q qg m q N( k
1. All terms consistent w/ Lorentz structure, P & T transformation, conservation laws
m (2kq+ qm (2kq+ q NkqqqNkNkq()(),,,,+gm( = + g m i g mnnn i g mn Nk( m m m m NNNN 2. Coefficients depend upon dynamical Lorentz invariants (masses and Q2 = - q2)
3. Two Gordon identities and one Ward identity (exactly as in g - 2)
mqq22 m mn qn NkqqqNk()()+g( = NkqFQ +12( g + iFQ( g Nk( 2mN 4. Nucleons point-like with small momentum transfer: q u F1 (0) number of valence quarks in the nucleon; e.g. for proton, F1 (0) = 2 q a= Q F q 0 F2 (0) quark contribution to anomalous magnetic moment of nucleon Nq 2 ( q= u,, d s
5. Input: ap & an from experiment; strange-quark contribution from lattice
6. Effectively can ignore qm n 2 N term Direct Detection
From scattering cross sections on nucleons to nuclear cross sections:
1. Nuclei not point-like: Q2=-2m 2 v 2( 1 cos * -1 v0 = 220 km s
m = Mc (Mc Mnucleus) 2 1/2 -1 Q = 50 MeV Mc50 = (4 fm / Mc50 )
2. Involves nuclear form factors/response functions q u nucleons: F1 (0) number of valence quarks in the nucleon, F1 (0) = 2 q -1 nuclei: F1 (0) number of valence quarks in the nuclei within (4 fm / Mc50 ) require nuclear form factors Direct Detection Spin-Independent Scattering 10-36 cm2 = 1 picobarn
10-39 cm2 = 1 femtobarn
10-42 cm2 = 1 attobarn
10-45 cm2 = 1 zeptobarn!
10-48 cm2 = 1 yoctobarn
M. Fedderke Direct Detection Spin-Dependent Scattering
M. Fedderke Direct Detection Spin-Independent Scattering
- 3 EFT: mf L cc f f Minimal Flavor Violation
M. Fedderke Direct Detection Spin-Independent Scattering
- 2 m EFT: L c g cff gm
M. Fedderke Direct Detection Spin-Dependent Scattering
- 25m EFT: L c g cff gm5
M. Fedderke SWIMPs/Direct-Detection Relationship
Spin-independent (scalar) Spin-dependent (axial vector) c c c c c c c c q% H, h Z q q q q q q q q
• Spin-independent/dependent ratio depends on model parameters
• Cross section depends on model parameters, can vary many, many orders of magnitude Direct Detection
One analysis of one of many possible SUSY frameworks
d
e e
Vries et et al. 2015 Direct Detection: The Present Maverick WIMPs (for given M, choose L relic abundance): Vector couplings excluded in range 10 GeV to 2000 GeV Scalar couplings excluded in range 10 GeV to 200 GeV Axial & Tensor couplings spin-dependent, weak or no limits Pseudoscalar couplings velocity suppressed no limits
SWIMPs (choose 100 or so SUSY parameters): Any limits very model dependent Direct detection limits constraining LHC+ pushing SUSY scale high pushing to higher-mass SWIMPs Direct Detection: The Future
Excluded N c New Region s Techniques
Also: Directionality Different mass targets Supersize Spin-dependent s
mass Direct Detection: The Future The path is clear (at least to me) (Goal is to discover WIMP or kill a 39-year old idea.)
• Push spin-independent limits down to neutrino background – no more than 2 orders-of-magnitude below proposed experiments • Lot of white space for spin-dependent limits • Push sensitivity to lower WIMP mass (new techniques?) • If see a signal: − Seasonal variations − Different targets − Directional sensitivity • If don’t see a signal: − Think beyond nuclear recoil − Work on 21cm astrophysics Indirect Detection
s v 10-36 cm2 310-26 cm3 s-1 Indirect Detection
Galactic Center Dwarf spheroidals DM clumps, Sun
Wimps Indirect Detection
dEF ( ) dN s v r 2 éùr( s,, l b) = gn, A ëûdscos bdbdl ò 2 dE dE42p line of region of M WIMP sight interest What to look for Where to look for it
• Charged particles: p, high-energy e-e+ • Galactic Center easy to detect know where to look astronomical backgrounds largest signal bent by magnetic field largest backgrounds
• Continuum photons, neutrinos • Nearby subclumps g easy to detect clean: no baryons astronomical backgrounds don’t know where to look n hard to detect/often not dominant signal down 10-3
• Monoenergetic photon line (cc gg ) • Dwarf spheroidals (M/L) > 3000 low background know where to look (about 20) (probably) low signal clean: very few baryons “golden” detection channel signal down another 10-3 Indirect Detection
PAMELA
ATIC MAGIC Fermi/GLAST
IceCube Veritas
H.E.S.S.
AMS-02 Indirect Detection: Maverick WIMPs DM SM DM SM
Wh2 L (M) G1 G2
DM SM DM SM s v = a + b v 2 s = c + d ( v + Q ) 2 EFT A S W : v2 1/20 spin-independent/-dependent operator DM indirect detection: v2 10-6 direct detection: v2, Q2 10-6 cc q q suppressed independent cc qg 5q suppressed suppressed cg 5c q q unsuppressed suppressed cg 5c qg 5q unsuppressed suppressed m cg c qgm q unsuppressed independent m cg c qgm5 q unsuppressed suppressed m5 cg c qgm q suppressed* suppressed m5 cg c qgm5 q suppressed* dependent mn cg c qgmn q unsuppressed dependent mn5 cg c qgmn q unsuppressed suppressed Maverick WIMPs
WIMP FERMION Signal or lack thereof operator(s)
DIRECT (SI) + INDIRECT V V DIRECT (SD) + INDIRECT T T
DIRECT (SI) + INDIRECT S S DIRECT (SD) + INDIRECT A A
DIRECT + INDIRECT P P, P S, V A
DIRECT + INDIRECT S P, A V SWIMPs/Indirect-Detection Relationship
• Low-energy annihilation cross section depends on neutralino composition, mass, and coupling and possibly other masses; all of these depend on about 100 SUSY parameters
• Generally both velocity-independent & velocity-suppressed parts
• Relative size depends on model parameters
• Many possible final states depending on model parameters
• Many possible diagrams depending on model parameters
• Branching fractions depending on model parameters
2 • Annihilation to fermions µ m f
• No two-body final state with a photon (at lowest order)—no g - ray “lines” Diffuse g-Rays from the Galactic Center Goodenough, Hooper, Dalyan, Portillo, Rood, Boyarsky, Malyshev, Ruchayskiy, Linden, Abazajian, Kaplinghat, Gordon, Macias, Canac, Horiuchi, Slayter, Berlin, Cholis, McDermott, Lin, Finkbeiner, Calore, Cholis, Weniger, … • Start with FERMI public data and tools • Pick search region of interest (around galactic center) • Remove point sources and model and remove every non-DM astrophysical source • Fit excess (if any) to cross section & annihilation channel(s)
Dalyan, et al. 1402.6703 Calore, Cholis, Weniger JCAP 2015
M = 32.25 GeV Model Parameters c 2 dof p -value annihilation to bb -26 3 +0.22 + 0.13 + 0.23 s v = 1.710 cm /s BPL aa1= 1.42--- 0.31 1 = 2.63 0.095 EB = 2.06 0.17 GeV 1.06 0.39 +6.4 + 0.28 - 26 2 bb M = 49--5.4 GeV s v = 1.76 0.27 ´ 10 cm 1.08 0.36 +4.6 + 0.2 - 26 2 cc M = 38.2--3.9 GeV s v = 1.25 0.18 ´ 10 cm 1.07 0.37 + 0.047+- 0.2 26 2 tt M = 0.337- 3.9 GeV s v=´ 1.25- 0.18 10 cm 1.52 0.06 Indirect Detection: The Future The path is clear (at least to me) (Goal is to discover WIMP or kill a 39-year old idea.)
• Have an overwhelmingly statistically significant g -ray excess from GC • Why aren’t we all as excited as Dan Hooper? • Possible background contamination (thousands of millisecond pulsars, …) • Better astrophysical understanding of galactic center IceCube • Better understanding of dark-matter density profile • Better observations − Better angular resolution (resolve background sources, remove emission correlated with gas, …) − Better spectral resolution − More collecting area—look for signals elsewhere, stacked dwarfs, etc. − Ground observations, e.g., CTA will teach us about backgrounds WIMPs at the LHC
Looking for an invisible needle in a haystack Maverick WIMPs at the LHC DM SM Wh2 L (M) G1 G2
sP (M) DM SM EFT sP In relativistic limit = c + doperator ( v + Q ) 2 spin-independent/-dependent cc q q spin independent cc qg 5q v2, Q2 suppressed cg 5c q q v2, Q2 suppressed cg 5c qg 5q v2, Q2 suppressed m cg c qgm q spin independent m s2ame2 for all operators cg c qgm5 q v , Q uppressed m5 2 2 cg c qgm q v , Q suppressed m5 cg c qgm5 q spin dependent mn cg c qgmn q spin dependent mn5 2 2 cg c qgmn q v , Q suppressed Maverick WIMPs at the LHC jet q c q c
q c q c Final state: nothing! Final state: an energetic jet of particles unbalanced in momentum • Look for “monojets” • Monojets are Nature’s garbage can • Also mono-g’s & mono-Z’s, inclusive b jets • SM background extremely well modeled and understood • Neutrino background can be removed • Couplings irrelevant in relativistic limit • Validity of EFT?
Beltran, Hooper, Kolb, Krusberg, Tait 2009; Goodman, Ibe, Rajaraman, Shepard, Tait, Yu; Rajaraman, Shepherd, Tait, Wijangco; Bai, Fox, Harnik; Fox, Harnik, Kopp, Tsai; CDF, CMS, ATLAS, … SWIMPs at the LHC Most popular cold thermal relic: the neutralino
• Gluinos, squarks, charginos will be discovered first • Analysis model dependent • LHC chewing away allowed region • Can swiggle out … but it is getting harder • Don’t throw in towelino just yet • Stay tuned for results from 13 TeV run • Eventually will see WIMP in missing energy signals SWIMPs Trickle Down SUSYnomics D + l+ g U W g n nl _ l U c0 g D U W+ l+ nl nl g g _ U c0 g g® u u d d m++ m n n c c
Complicated decay chain—very model dependent Collider Searches: The Future
• LHC has just started running at 13 TeV • LHC will eventually accumulate a tremendous amount of data • If DM is a SUSY relic, some indication of SUSY will be discovered at LHC − gluinos, squarks, charginos, will be seen first − search strategies well developed • If DM is a Maverick particle − only hope is missing-energy searches − most effective for low masses − no guarantee EFT valid at LHC Dark Matter: If Not a WIMP
• If DM not a WIMP, many other possibilities: − Axions − Asymmetric DM − Sterile neutrino DM (e.g., 7 keV sterile neutrino producing 3.5 keV X-ray line which may, or may not, be observed) − Axino (7 keV axino) DM − Self-interacting DM − Inelastic DM − Q-balls or other solitonic DM − Quark nuggets − Hidden-sector DM − WIMPZILLA Dark Matter: The Future
• We are in the eighth decade of Dark Matter! • 2010s is the Decade of the WIMP − LHC − Direct detection − Indirect detection Have to run to ground the WIMP (cold thermal relic) hypothesis. • Indirect/Direct/LHC confusion not an issue • WIMPs may be more complicated than discussed: Leptophilic, Leptophobic, Flavorful, Self-Interacting, Dynamical, Inelastic, … • My predictions: − We will know the answer before a century of dark matter − Dark matter discovery will be unanticipated − Dark matter will be “none of the above” − Dark matter will be multicomponent − Dark matter will be part of a dark sector Discovery of Dark Matter Would be HUGE! Dark Matter
Rocky Kolb LPC 2 March 2016 Backup slides Supersymmetry & Dark Matter: A Match
Seeking a Superpartner Seeking an Embedding
Super-mature, 41-year-old WIMPy 35-year-old theory (SUSY) desperately particle species seeks a seeks a partner for a theory (any theory) in physical manifestation. which to be embedded. DAMA/LIBRA (NaI)
cos w (t - t0) T = 2p /w = 1 year d t0 = 152.5 (2 June)
Amplitude of modulation surprisingly high
KIMS (CsI) modulation not due to WIMP scattering on Iodine CoGeNT (Ge)
1208.5737
30% surface events, low-mass (10 GeV) WIMP with large cross section (10-4 pb) CDMS II Si Analysis April 2013
1304.4279 Limits: Blue (Red) = CDMS Si (Ge); Green = XENON; Orange = EDELWEISS Signal?: Yellow = CoGeNT; Tan = DAMA/LIBRA; Pink = CRESST Combined: Blue region 68% and 90% C.L. EFT: DM Couples to EWK Gauge & Higgs (Chen, Kolb, Wang 13050021)
c q
Most EFT approaches assume DM couples to SM fermions
c q
Why not EWK gauge = g , W , Z and Higgs = h c c c
c c c EFT: DM Couples to EWK Gauge & Higgs
• Gamma-ray observations for this case play the role of direct detection for coupling to quarks
• Fifty operators/34 without velocity suppression Thirteen + - DM+DM → gg, gZ, gh, W W , ZZ, Zh, hh, ff different For each operator calculate photon spectrum (lines+continuum) classes Compare to various constraints
] WW 1
- Zh s
3 gh
cm
[ v
s Direct Detection—Low Recoil Energies
DAMIC: Target: Si in CCD Low-readout noise ~ 2푒− Position reconstruction Fermilab, Chicago, Zurich, Michigan, UNAM, FIUNA, CAB Fermi/GLAST Line(s) Dwarf stacking inconclusive Geringger-Saneth, & Koushiappas 1206.0796
129 GeV c + c g + g 111 GeV c + c g + Z
22 E12= mc E = m c( 1 - m c 4 mz ) Six stacked galaxy clusters: 3.2s signal Hektor, Raidal, Tempel 1207.4466 About 3s: Finkbeiner & Su 1207.7060 Maverick WIMPs Coupling to Quarks
Dirac fermion Maverick WIMP, c
1 éù Expect Yukawa-like (S,P) =2 [cc Gij] ×qq G L å ëûêú couplings mq (MFV) q M* G=1,g55 , gm , g m , g mn Some terms vanish for ij, { } Majorana c
Complex scalar Maverick WIMP, f
éù† êúff 1 êú =ff† ¶m +h.. c ×éù q G q L å n êúëûêúj q M* êú êúiff†¶-m h.. c ëû( ) Collider Searches for Maverick WIMPs
protons WIMPsJET + WIMPs
proton
WIMP WIMP WIMP WIMP
proton
Discover WIMPs by searching for “monojets” (MET) WIMP Questions • Why only one WIMP? The 4% of matter we see is pretty complex and varied. If social network of several WIMPs, stronger interacting ones: − Easier to detect − Smaller W
• Thermal Production of WIMPS? − Super-WIMPs − Asymmetric freeze out − Dilution after freeze out via entropy production
• Maverick WIMPs? − Suppose LHC only sees SM Higgs? − Wither SNOOZY?
• Leptophilic, Leptophobic, Flavorful, Self-Interacting, Dynamical, Inelastic, …
• Annual modulation: do we really understand DM phase space?
• Indirect detection gives indirect information Predicted LHC Sensitivity Rajaraman et al. PRD 2011 Predicted LHC Sensitivity Rajaraman et al. PRD 2011 ATLAS Results 1210.4491
8 = Axial
9 = Tensor CMS Results JHEP 2012 Take Advantage of Largest Yukawas (Lin, Kolb, Wang 13036638) Take Advantage of Largest Yukawas (Lin, Kolb, Wang 13036638)
S & P couplings mq (Minimal Flavor Violation) mc : mb : mt :: 1 : 3.3 : 135 So far, analysis includes only c (b PDF smaller than c PDF) but mt mb mc
Take advantage of b tagging
Top PDF small (& very uncertain) but mt huge Looks like stop signal—use stop search limits Take Advantage of Largest Yukawas (Lin, Kolb, Wang 13036638)
Light WIMPs From Direct Detection?
bin keV CoGeNT
DAMA/LIBRA counts per 0.05 per counts
Energy (keVee)
CDMS Si
CRESST Direct Detection
Cooley, PONT 2014 Direct Detection
Cooley, PONT 2014 Direct Detection Low-mass region: either unexplained backgrounds in DAMA, CoGeNT, CRESST-II, CDMS II/Si … or … other experiments do not understand low recoil-energy calibration, … or … can’t compare different experiments
High-mass region: Reaching shades of grey of the CMSSM iceberg, just as heat from LHC melts it! Direct Detection
Axial Vector Axial Vector
M. Fedderke Indirect Signals Have Come (and Gone?)
ATIC Chang et al, 2008
620 GeVFERMI WIMP
FERMI 2012 Weniger 1204.2797 Weniger
Han et al. (2011) WIMPs
For low-momentum transfer can use EFT for WIMP—quark interaction
Momodesigns
EFT sA v WIMP annihilation s WIMP—nucleus 2 2 -6 operator WDM: v 1/20 (direct detection) v 10 indirect detection: v2 10-6 Spin velocity / Q2 cc q q v2 independent unsuppressed cc qg 5q v2 dependent Q2 cg 5c q q unsuppressed independent Q2 cg 5c qg 5q unsuppressed dependent Q4 m cg c qgm q unsuppressed independent unsuppressed m5 2 2 2 2 cg c qgm q v & mq /M independent v dependent Q2 m 2 2 cg c qgm5 q unsuppressed dependent v & Q m5 2 2 2 cg c qgm5 q v & mq /M dependent unsuppressed mn cg c qgmn q unsuppressed dependent unsuppressed mn5 cg c qgmn q unsuppressed dependent WIMPs
For low-momentum transfer can use EFT for WIMP—quark interaction
Momodesigns
EFT sA v WIMP annihilation s WIMP—nucleus 2 2 -6 operator WDM: v 1/20 (direct detection) v 10 indirect detection: v2 10-6 Spin velocity / Q2 cc q q v2 independent unsuppressed cc qg 5q v2 dependent Q2 cg 5c q q unsuppressed independent Q2 cg 5c qg 5q unsuppressed dependent Q4 m cg c qgm q unsuppressed independent unsuppressed m5 2 2 2 2 cg c qgm q v & mq /M independent v dependent Q2 m 2 2 cg c qgm5 q unsuppressed dependent v & Q m5 2 2 2 cg c qgm5 q v & mq /M dependent unsuppressed mn cg c qgmn q unsuppressed dependent unsuppressed mn5 cg c qgmn q unsuppressed dependent LUX (arXiv:1512.050) spin-independent Fermi/GLAST Line(s) • WIMP−charged particle coupling annihilates to g g + g Z + ZZ + ...).
Bergstrom & Ullio 97
• But also annihilates at tree-level to W ’s and Z ’s, e+e-, quarks, …, producing “continuum” g -ray background. Loop smaller than tree by (a 2/4p). • Inner bremsstrahlung also produces g ’s, only suppressed (a). • Continuum constrained by observations, BR(g g ) must be (1). • Models with no tree-level annihilation: e.g., Jackson et al. 0912.0004 Neutrino Background for Mavericks
Once thought that n n background Renormalizible q + q Z n + n
q Z n s s-1 (parton level) q n
Would swamp WIMP signal Nonrenormalizible
q + q c + c q c s s (parton level) q c
Judicious cuts on MET can pull out signal CMS Analysis JHEP 2012 ATLAS Analysis 1210.4491
1 = Scalar 5 = Vector
2 (Gmn) Direct Detection
10-40 GeV
-42
100 100 10
- 60 10-44
10-46
) around )
2 cm ( 10-48 s 1995 2000 2005 2010 2015 2020
Vuk Mandic; Laura Baudis Collider Searches for Maverick WIMPs
Maverick Monojets • Monojets are Nature’s garbage can
• Also monophotons & mono-Z’s
• SM background extremely well coupling from W modeled and understood or direct/indirect Neutrino background
EFT?
Beltran, Hooper, Kolb, Krusberg, Tait 2009; Goodman, Ibe, Rajaraman, Shepard, Tait, Yu; Rajaraman, Shepherd, Tait, Wijangco; Bai, Fox, Harnik; Fox, Harnik, Kopp, Tsai; CDF, CMS, ATLAS
The Decade of the WIMP • Is WIMP “miracle” coincidence or causation? • Situation now is muddled • By the end of this decade the WIMP hypothesis will have either convincing evidence or near-death experience − Direct detection will reach 10-12 pb (10-48 cm2!) -28 3 -1 − Indirect detection will probe sAv 10 cm s − LHC will explore energy scales up to the TeV region • Three possible discovery miracles: 1. Direct 2. Indirect 3. Colliders • Require three WIMP miracles? (Two needed for sainthood.) • At any rate, this is the decade of the WIMP! Effective Field Theory (EFT) g • WIMP is the only state accessible to experiments: c q other states too massive (Maverick) q% • Many theories have common low-energy behavior c q when mediating particles heavy compared to g energies involved
MMQ2? 2, 2 • EFT not as desirable as a UV-complete theory: q% c • miss relations between quantities • can’t describe high-energy behavior (possibly like LHC) c q
• Example: low-energy (E mZ) n physics 2 c g - 2 q GF m qq 2 =L L = n g(1- g55) n ×q gm ( gVA - g g ) q M 2 q%
-n • Maverick: L = M* JDM · JSM JDM & JSM SM singlets WIMPs Interact with SM Particles Indirect Detection
Relic Abundance STANDARD-MODEL WIMP PARTICLE
2 Direct Wh Detection
STANDARD-MODEL WIMP PARTICLE Collider Production