Upload
bonner
View
71
Download
3
Embed Size (px)
DESCRIPTION
Cosmology and Particle Physics. What we may Learn from Future Physics Experiments Andris Skuja University of Maryland. Status of Particle Physics and Cosmology. The parameters of particle physics have been used effectively to construct the present Standard Model of Cosmology - PowerPoint PPT Presentation
Citation preview
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 1
Cosmology and Particle Cosmology and Particle PhysicsPhysics
Cosmology and Particle Cosmology and Particle PhysicsPhysics
What we may Learn from Future Physics Experiments
Andris Skuja
University of Maryland
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 2
Status of Particle Physics Status of Particle Physics and Cosmologyand Cosmology
Status of Particle Physics Status of Particle Physics and Cosmologyand Cosmology
The parameters of particle physics have been used effectively to construct the present Standard Model of Cosmology
But the Cosmological model contains more than particle physics. It traces the evolution of the Universe from the Big Bang through Inflation to photon decoupling, and to the present. Recent measurements of the CMB by WMAP and other experiment have placed stringent limits on particle physics models, from neutrino masses to SUSY mSUGRA models.
On the other hand any laboratory measurements of particle physics parameters that are in disagreement with the Cosmological Model may generate problems of interpretation for the SCM.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 3
Topics of InterestTopics of InterestTopics of InterestTopics of Interest
Matter-Antimatter Asymmetry• Neutrinos (and more)
Dark Matter (Cold Dark Matter)• Supersymmetry & WIMP’s• Neutrinos• Axions
Inflation• Quintessence
Accelerating Universe• Sterile Quintessence
Magnetic Monopoles (none found)Higher Dimension Universes
• Mini–black holes from higher dimensions• Topological defects (cosmic strings, etc.)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 4NASA/WMAP Science Team
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 5Marc Kamionkowski
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 6
Measuring the Afterglow of Measuring the Afterglow of the Big Bangthe Big Bang
Measuring the Afterglow of Measuring the Afterglow of the Big Bangthe Big Bang
WilkinsonMicrowaveAnisotropyProbe(WMAP)
Launched:Summer, 2001
(NASA/WMAPScience Team)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 7
The Sonogram in The Sonogram in Numbers:Numbers:Angular Power Angular Power SpectrumSpectrum
TopTop: Temperature : Temperature fluctuations vs. fluctuations vs. angular scaleangular scale
BottomBottom: Cross-: Cross-correlation of correlation of temperature and linear temperature and linear polarizationpolarizationvs. angular scalevs. angular scale
The Sonogram in The Sonogram in Numbers:Numbers:Angular Power Angular Power SpectrumSpectrum
TopTop: Temperature : Temperature fluctuations vs. fluctuations vs. angular scaleangular scale
BottomBottom: Cross-: Cross-correlation of correlation of temperature and linear temperature and linear polarizationpolarizationvs. angular scalevs. angular scale
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 8
Dark EnergyDark EnergyDark EnergyDark Energy
WMAP measures a dark energy density of ΩΛ~0.7 (as required if ΩTOTAL~1.0) .
Any calculation of the energy density of the Universe using Particle Theory obtains answers that disagree with observation and the Cosmological Model by 60 to 120 orders of magnitude.
This disagreement between the cosmological measurement and particle physics estimate is usually ignored. We have to conclude that we do not have a good model for the Dark Energy source.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 9
Cosmic Coincidence Cosmic Coincidence ProblemProblem
Cosmic Coincidence Cosmic Coincidence ProblemProblem
Why do we see matter and cosmological constant almost equal in amount?
“Why Now” problem
Actually a triple coincidence problem including the radiation
If there is a fundamental reason for ~((TeV)2/MPl)4, coincidence natural
Arkani-Hamed, Hall, Kolda, Muramaya
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 10
Matter – AntiMatter Matter – AntiMatter AsymmetryAsymmetry
Matter – AntiMatter Matter – AntiMatter AsymmetryAsymmetry
It is thought that the entire Universe consists predominately of matter only. Otherwise we would be able to observe high energy gammas caused by the annihilation of mater/antimatter
However, the standard model of particle physics does not contribute enough to the matter /antimatter asymmetry to account for the present observations.
Standard Cosmology leads one to believe that some extension of the Standard Model is necessary to account for our observations
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 11
CP violation in the Neutrino CP violation in the Neutrino SectorSector
CP violation in the Neutrino CP violation in the Neutrino SectorSector
Maximal CP violation in the (massive) neutrino sector may be responsible for saturating the matter/antimatter asymmetry observation.
It is conjectured that not only do the 3 types of massive neutrinos oscillate from one flavor eigenstate to another (just as in B physics), but that the mass eigenvectors and the flavor eigenvectors are connected by a matrix that has maximally violating CP phase.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 12
Disappearance measurements cannot see CP violation effect
Very, very hard to see CP violation effects in exclusive (appearance) measurements. (From B. Kayser)
• Only can see CP violation effects if an experiment is sensitive to oscillations involving at least three types of neutrinos.
• All the terms (s12, s13, s23) must not be 1 or effectively becomes only two component oscillation• For example, if s31 0 then s12 s23 s12 + s31 + s23
To see CP violation must be sensitive to all three neutrino oscillations i.e. the hardest is usually the lowest (solar neutrino) m2 eV2
CP Violation in Neutrino CP Violation in Neutrino OscillationsOscillations
CP Violation in Neutrino CP Violation in Neutrino OscillationsOscillations
2222
3123123*
3*11
2sin
)(Im4
jiijij
eeee
mmmELm
sssUUUUPP
and s where ij
PP
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 13
Matter-Antimatter Asymmetry (Matter-Antimatter Asymmetry (B B 0) 0)from Leptogenesisfrom Leptogenesis
Matter-Antimatter Asymmetry (Matter-Antimatter Asymmetry (B B 0) 0)from Leptogenesisfrom Leptogenesis
Hard to generate a baryon asymmetry (B 0) using quark matrix CP violation
Generate L 0 in the early universe from CP (or CPT) violation in heavy neutrino N3 vs.decays (only needs to be at the 10-6 level)
B-L processes then convert neutrino excess to baryon excess.• Sign and magnitude ~correct to generate baryon
asymmetry in the universe with mN > 109 GeV and m < 0.2 eV
N3 N3
3N
Mixing Mixing
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 14
e.g.Neutrino factory Golden Signature of “wrong sign” muons
CP Violation at a Neutrino Factory (Ken Peach)
ee
“right sign muons”
“wrong sign muons”
( )eP
ee
“right sign muons”
“wrong sign muons”
( )eP
( )eP ( )eP ( )eP CP odd
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 15
Neutrino Factory (Proposed) Neutrino Factory (Proposed)
Neutrino Factory (Proposed) Neutrino Factory (Proposed)
•High intensity: 1021 /yr
•Energy: 30-50 GeV for muons
•Low backgrounds
•Two experimental sites
•3000 Km
•1000 (7000) km
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 16
What is a Superbeam? • Pretty much a “regular” neutrino beam but with a very intense proton
beam.
• Generally, proton power > ~1 MW puts you in “the club”.
• However, “off-axis” or other types of beams may have some interesting advantages.
Everybody wants to be at one end or the other of one!
Almost every conceivable combination of proton accelerator laboratory and large underground laboratory/experiment seems to have been suggested. Particular studies have been made at CERN, KEK/JHF, Brookhaven and Fermilab.
The physics motivation which is currently driving most of these efforts is to search for a small admixture of e mixing with m2~ 0.003 eV2 where CP violation may also exist.
The picture could change significantly depending on the results from experiments like Kamland and Mini-Boone.
Neutrino SuperbeamsNeutrino SuperbeamsNeutrino SuperbeamsNeutrino Superbeams
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 17
Leptogenesis may be Leptogenesis may be insufficientinsufficient
Leptogenesis may be Leptogenesis may be insufficientinsufficient
It may be that CP violation in the neutrino sector may also be insufficient to account for maximal matter/antimatter asymmetry. It may not be due to numerology –trivially the numbers may add up. Recent Theoretical papers suggest that the mechanism for generating the baryon asymmetry is difficult to evoke during the time available during early expansion, even if SUSY is included (e.g. see recent review of W. Bernreuther of Achen)
The seemingly obvious cosmological observation of a predominantly matter Universe has major consequences for particle physics. A GUT of particle physics is preferred at intermediate scales in Cosmological Models generating the baryon asymmetry.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 18
Most of the Universe is not made up ofatoms: Ωtot~1, Ωb~0.04, Ωm~0.3Most is Dark Matter and Dark Energy
Most Dark Matter is Cold (non relativistic at freeze out)Significant Hot Dark matter is disfavoredNeutrinos are not very cosmologically relevant: Ων<0.015 (WMAP)
WMAP
SUSY has excellent DM candidates: NeutralinosAlso Axions may still be viable
For 3 neutrinos: Ων< 0.015 -> mν< 0.23 eV ~ 5(Dm2atm)1/2
WMAP and Dark MatterWMAP and Dark MatterWMAP and Dark MatterWMAP and Dark Matter
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 19
Galaxy Rotation CurvesGalaxy Rotation CurvesGalaxy Rotation CurvesGalaxy Rotation Curves
NGC 3198
Measure the velocity of stars and gas clouds from their Doppler shifts at various distances
Velocity curve flattens out!
Halo seems to cut off after r= 50 kpc
v2=GM/r where M is mass within a radius r
Since v flattens out, M must increase with increasing r!
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 20
Hot Gas and GalaxiesHot Gas and GalaxiesHot Gas and GalaxiesHot Gas and Galaxies
Measure the mass of light emitting matter in galaxies in the cluster (stars)
Measure mass of hot gas - it is 3-5 times greater than the mass in stars
Calculate the mass the cluster needs to hold in the hot gas - it is 5 - 10 times more than the mass of the gas plus the mass of the stars!
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 21
Dark Matter HaloDark Matter HaloDark Matter HaloDark Matter Halo
The rotating disks of the spiral galaxies that we see are not stable
Dark matter halos provide enough gravitational force to hold the galaxies together
The halos also maintain the rapid velocities of the outermost stars in the galaxies
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 22
Modified DynamicsModified DynamicsModified DynamicsModified Dynamics
Mordehai Milgrom of the Weizmann Institute has propsed that standard Newtonian dynamics should be modified (MOND) for large scale low density systems. He has worked out a detailed scheme of how this occurs. He can account for all astronomical observations using a very detailed model of galaxies and his proposed dynamics. If true, in this case ΩCDM would be zero.
Stacey McGaugh of the University of Maryland has compared MOND predictions for low surface brightness galaxies with considerable success. He is a MOND believer. He is also very lonely !!
MOND appears to be inconsistent with the WMAP measurements (ΩM= 0.3 and ΩB= 0.04). McGaugh has calculated an anisotropy spectrum for the CMB based on MOND dynamics and claims it agrees with the BOOMERANG data.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 23
WMAP Anisotropy SpectraWMAP Anisotropy SpectraWMAP Anisotropy SpectraWMAP Anisotropy SpectraResults
Bennett et al. (2003)
• Position and height of firsttwo peaks pinned down
• Polarization helps by determining extent of reionization
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 24
CMB sorts out Mass densityCMB sorts out Mass densityCMB sorts out Mass densityCMB sorts out Mass density
Decrease in matter density leads to enhanced peaks
Position of first peak (in flat universe) is affected by matter density
CMB can break degeneracy
CMB appears to rule out ΩM= 0.1 or smaller Modern Cosmology (2003)
Dodelson
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 25
Dark Matter CandidatesDark Matter CandidatesDark Matter CandidatesDark Matter Candidates
Non Baryonic dark matter could take many forms:
• Axions
• Neutrinos (Hot Dark Matter)
• Supersymmetric Particles (Cold Dark Matter) (Neutralinos)
• Other WIMPS
Models of Large Scale structure formation indicate that Hot Dark Matter is excluded as the sole source of this phenomena. However, recent more detailed calculations indicate the Cold dark matter also does not yield the observed distribution of matter density in Large Scale structures (galaxies, etc.). A number of cosmologists argue that when both baryonic an CDM are included, such discrepancies will disappear. However, the work still must be done.
New measurements of neutrino masses and/or the discovery of the axion could be a complication.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 26
Axions as Cold Dark MatterAxions as Cold Dark MatterAxions as Cold Dark MatterAxions as Cold Dark Matter
Extremely light particles, with masses in the range of 10-3 eV/c2 to 10-6 eV/c2 . The upper bound is set by neutrino fluxes from Supernova SN 1987 A, while the lower bound saturates the matter budget of the Universe (ΩA= 1.0) . Several axion searches are in progress – one exploring the lower bound while the other the upper bound.
Interactions are 1012 weaker than ordinary weak interaction
Density would be 108 per cubic centimeter
Velocities are low
Axions may be detected when they convert to low energy photons after passing through a strong magnetic field
Y. Grossman et al. suggest that distant SuperNova appear dim because about 1/3 of their photons convert into axions on the way to earth.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 27
The QCD Lagrangian includes a gluon-gluon interaction term whichviolates CP (and T):
GGsCP
~8
L
GG
21~
parameter describing the QCD vacuum and depending also on quark mixing
Such a term predicts an electric dipole moment for the neutron:
cmeAd n 10 15
Present experimental limit |dn| < 0.63 x 10-25 e x cm
< 10-9
With (A = 0.04 – 2.0)
WHY SO SMALL?
The Strong CP ProblemThe Strong CP ProblemThe Strong CP ProblemThe Strong CP Problem
This implies
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 28
Peccei-Quinn add a new, massless pseudoscalar field a(x) (The AXION) interacting with the gluon field. Add new term to Lagrangian: GaGa
f a
sa
~82
1 2
L
Kinetic term Peccei-Quinn scale
La (CP conserving) is invariant for a a+ constant is “absorbed” in the definition of aAxion-gluon vertex a q q transitions a – 0 mixing mass ma > 0 eV
GeVff
mfm
aa
a
)(6.0
476.0107
(0 decay constant f = 93MeV)
Proposed Solution of the Proposed Solution of the Strong CP Problem Strong CP Problem
Proposed Solution of the Proposed Solution of the Strong CP Problem Strong CP Problem
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 29
axion-0 mixing axions couple to photons
(coupling strength with respect to 0 reduced by ~ f/fa)
ag aa BE L
92.1
2 NE
fg
a
a
model-dependent parameter of order 1E/N=8/3 in GUT models
Astrophysical arguments (energy loss of globular cluster stars)
(Raffelt 1996):11010 GeVg a
Axion couplingAxion couplingAxion couplingAxion coupling
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 30
LLNL Axion searchLLNL Axion searchLLNL Axion searchLLNL Axion search
The light axion interacts with a strong (tuned) magnetic field to produce a free photon in the microwave range. The experiment detects the final state photons (or sets a limit on their production). Assuming the axion flux permeats the galaxy halo at the earths surface one can observe/exclude such models.
An axion with mass 1-2 m eV would close the energy density of the universe during inflation (ΩA= 1.0). An Axion of mass 1000 greater , on the other hand would only contribute ΩA= 0.01. A very light axion would contribute to the acoustic peak paramaterization of the CMB, and appears to be excluded by the WMAP measurements.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 31
Slide provided by Prof. N. SugiyamaVery Light Axions appear to be excluded by WMAP
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 32
Axion hardwareAxion hardwareAxion hardwareAxion hardware
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 33
(C. Hagmann et al., Phys. Rev. Lett. 80 (1998) 2043)
First Data at KSVZ First Data at KSVZ sensitivitysensitivity
First Data at KSVZ First Data at KSVZ sensitivitysensitivity
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 34
Local axion halo density Local axion halo density excludedexcluded
Local axion halo density Local axion halo density excludedexcluded
0.1
1
10
550500 600 650 700 750 800 850
Frequency (MHz)
Axion mass (eV)2.00 2.25 2.50 2.75 3.00 3.25 3.50
DFSZ
KSVZ
(
Ge
v/c
m3)
Abbreviations (previous Slide) :
UF – University of Florida
RBF – Rochester/BNL/FNAL
This Slide – LLNL/MIT/Florida/LBNL/FNAL/INR(Moscow)
KSVZ – Kim-Shifman-Vainshtein-Zakharov (and an axion coupling constant to photons of - 0.97)
DFSZ – Dine-Fischler-Srednicki-Zhitnitskii (and an axion coupling constant to photons of 0.36)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 35
+ Z + Z aa+ Z+ Z + Z + Z aa+ Z+ Z
Axions may be produced in the sun by thermal photon-nucleus interactions in the Sun core (T~15.6 MOK)
Solar axion differential flux on Earth
(K. van Bibber et al., 1989) Photons/(cm2 s keV) for ga = 10-10 GeV-1 (Flux proportional to ga
)
Solar Axion ProductionSolar Axion ProductionSolar Axion ProductionSolar Axion Production
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 36
Existing exclusion regions and CAST expected sensitivity
Tokyo “helioscope”: L=2.3 m dipole, B=4T, aperture=2.0x9.2cm2
vertical movement ±28° w.r. to horizontal plane
CAST and Tokyo HelioscopeCAST and Tokyo HelioscopeCAST and Tokyo HelioscopeCAST and Tokyo Helioscope
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 37
Magnet Feed Box (MFB)being connected to the magnet
magnetHe4 flexible transfer line
CAST uses an LHC SC magnet CAST uses an LHC SC magnet as an Axion Telescopeas an Axion Telescope
CAST uses an LHC SC magnet CAST uses an LHC SC magnet as an Axion Telescopeas an Axion Telescope
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 38
Magnet power supplyCold Box
Counting room
CAST: Looking at the SunsetCAST: Looking at the SunsetCAST: Looking at the SunsetCAST: Looking at the Sunset
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 39
NeutrinosNeutrinosNeutrinosNeutrinos
(Some) Neutrinos have mass. A series of experiments (Homestake, SuperK, SNO, KAMLAND and many others) over the last 30 years have established that neutrinos have mass and oscillate. They are continuing to take data. Particle Theorists would like neutrinos to be Majorana particles (neutrinos and anti-neutrinos are the same particle).
Neutrinos are hot dark matter and relativistic. They “stream”.It is deemed that neutrinos alone could not form Large Scale Structure in the Universe.
0.021c
m
eV
With the neutrino mass limited to a fraction of an eV. The WMAP results indicate that
For 3 neutrinos: Ων< 0.015 -> mν< 0.23 eV
Dodelson, et al. have pointed out that degeneracies exist in the CDM power spectrum for neutrinos.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 40
Power Spectrum and Neutrino Power Spectrum and Neutrino Mass DegeneracyMass Degeneracy
Power Spectrum and Neutrino Power Spectrum and Neutrino Mass DegeneracyMass Degeneracy
Dodelson
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 41
• Lowering the matter density suppresses the power spectrum
• This is virtually degenerate with non-zero neutrino mass
Power Spectrum DegeneracyPower Spectrum DegeneracyPower Spectrum DegeneracyPower Spectrum Degeneracy
Dodelson
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 42
Running is degenerate with Running is degenerate with neutrino massneutrino mass
Running is degenerate with Running is degenerate with neutrino massneutrino mass
Abazajian, Dodelson, & Gates (2003)
Very preliminary result: running does alleviate bound on neutrino mass.In the future, to understand the details of the Power Spectrum, even small neutrino masses become important.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 43
3+1 Neutrino Mass Model3+1 Neutrino Mass Model3+1 Neutrino Mass Model3+1 Neutrino Mass Model
3+1 Model:• Atmospheric:
• Solar: LMA e
• LSND: s e
Solar oscillations are to a 50%/50% mixture of and
LSND e oscillations are through high mass, mainly s state with small admixture of and e
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 44
CPT Violation: MassesCPT Violation: MassesCPT Violation: MassesCPT Violation: Masses
If CPT is violated the
Model accommodates solar, atmospheric, and LSND without sterile neutrinos
• Just allow the antineutrino m2 to be bigger than the neutrino
• Theoretical prejudice is consistent with mass being of the order of the splittings
ii MassMass
e sees Solar but
sees LSND e
(Barenboim, Borissov, Lykken,Smirnov, Murayama, Yanagida;hep-ph 0201080)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 45
Supernova NeutrinosSupernova NeutrinosSupernova NeutrinosSupernova Neutrinos
In a super nova explosion • Neutrinos escape before the photons• Neutrinos carry away ~99% of the energy• The rate of escape for eis
different from and
(Due extra eCC interactions with electrons)
Neutrino mass limit can be obtained by the spread in the propagation time• tobs-temit = t0 (1 + m2/2E2 )• Spread in arrival times
if m0 due to E• For SN1987a assuming
emission time is over 4 sec m < ~30 eV
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 46
Solar Neutrino DeficitSolar Neutrino DeficitSolar Neutrino DeficitSolar Neutrino Deficit
Flux of solar neutrinos detected at the earth is much less than expected It is due to neutrino oscillations?
• The “Standard Solar Model” is OK
• Wide range of measurement techniques
• Confirmed by man generated neutrino fluxes
• All large experiments use Cherenkov detector techniques
Super- K (Japan) imageof the sun using neutrinos
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 47
Super-K ExperimentSuper-K ExperimentCherenkov DetectorsCherenkov Detectors
Super-K ExperimentSuper-K ExperimentCherenkov DetectorsCherenkov Detectors
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 48
Super-KamiokandeSuper-KamiokandeSuper-KamiokandeSuper-Kamiokande
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 49
Sudbury Neutrino Observatory Sudbury Neutrino Observatory (SNO)(SNO)
Sudbury Neutrino Observatory Sudbury Neutrino Observatory (SNO)(SNO)
1000 tons D2O(12m Inner Vessel)
Advantages of Heavy vs Light Water• e + dp + p + e (D2O)• e + ee + e (H2O or D2O)• Cross section (Ecm)2 = s
• s = 2 mtarget EsNse- = Mp/Me 2000
• But x5 more electrons in H2O than n’s
SNO (1kton) 8.1 CC events/daySuperK (22ktons) 25 events/day
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 50
The SNO Detector during The SNO Detector during ConstructionConstruction
The SNO Detector during The SNO Detector during ConstructionConstruction
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 51
Kamland – Terrestrial Kamland – Terrestrial NeutrinosNeutrinos
Kamland – Terrestrial Kamland – Terrestrial NeutrinosNeutrinos
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 52
Kamland Results (Dec. 2002)Kamland Results (Dec. 2002)Kamland Results (Dec. 2002)Kamland Results (Dec. 2002)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 53
KamlandKamlandKamlandKamland
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 54
Stat
istic
al e
rror
s on
ly
Chooz andChooz andPalo VerdePalo Verdemotivatedmotivated
by theby theatmosphericatmospheric
neutrinoneutrinoanomalyanomaly
KamLANDKamLANDmotivatedmotivated
by theby thesolarsolar
neutrinoneutrinoanomalyanomaly
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 55
J. Bahcall et alm2
(eV2)
Before Kamland After Kamland
Note the changeof scale between plots
Solar Neutrino SensistivitySolar Neutrino SensistivitySolar Neutrino SensistivitySolar Neutrino Sensistivity
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 56
MiniBooNE ExperimentMiniBooNE ExperimentMiniBooNE ExperimentMiniBooNE Experiment
MainInjector
Booster
12m sphere filled withmineral oil and 1500 PMTslocated 500m from source
Use protons from the 8 GeV booster Neutrino Beam GeV
Need definitive study of e at high m2 … MiniBooNE
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 57
MiniBooNE MiniBooNE has Startedhas StartedMiniBooNE MiniBooNE has Startedhas Started
Everything on schedule • Detector filled with oil
• Horn tested (107 pulses)
• Proton extraction ready
PMT installation completed in October.
Magnet Focusing Horn
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 58
MiniBooNE Sensitivity to LSND
With two years of running MiniBooNE should be able to completely include or exclude the entire LSND signal region.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 59
(MeV)
Direct Neutrino Mass Direct Neutrino Mass ExperimentsExperiments
Direct Neutrino Mass Direct Neutrino Mass ExperimentsExperiments
(keV)
e(eV)
Techniques• Electron neutrino:
• Study Ee end point for 3H3He + e + e
• Muon neutrino: • Measure P in
decays• Tau neutrino:
• Study n mass in n decays
WMAP limits are more stringent than individual experimental limits
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 60
ee Mass Measurements Mass Measurements(Tritium (Tritium -decay Searches)-decay Searches)ee Mass Measurements Mass Measurements
(Tritium (Tritium -decay Searches)-decay Searches)Search for a distortion in the shape of the -
decay spectrum in the end-point region. 3H3He + e + e
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 61
Next Generation Next Generation -decay -decay Experiment (Experiment (mm0.35 eV)0.35 eV)Next Generation Next Generation -decay -decay Experiment (Experiment (mm0.35 eV)0.35 eV)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 62
Dirac and Majorana Dirac and Majorana NeutrinosNeutrinos
Dirac and Majorana Dirac and Majorana NeutrinosNeutrinos
Dirac Neutrinos• Neutrino and Antineutrino
are distinct particles
• Lepton number conserved
• Neutrino
• Antineutrino
• Dirac Mass Term
Majorana Neutrinos• Neutrinos and Antineutrinos
are the same particle Only difference is “handedness”
• Neutrinos are left-handed
• Antineutrinos are right-handed
• Lepton number not conserved• Neutrino Antineutrino with
spin flip• Majorana Mass Term
See-Saw Mechanism with Both Majorana and Dirac Terms:
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 63
-- -- - - decay modes decay modes -- -- - - decay modes decay modes
• (A,Z) (A,Z+2) + 2 e- + 2e 2
0: Only possible if neutrinos are massive Majorana particles
• (A,Z) (A,Z+2) + 2 e- 0
• (A,Z) (A,Z+2) + 2 e- + (2) 0
-
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 64
Heidelberg-Moscow ExperimentHeidelberg-Moscow ExperimentHeidelberg-Moscow ExperimentHeidelberg-Moscow Experiment
Max-Planck-Institut für Kernphysik Max-Planck-Institut für Kernphysik Russian ScienceRussian Science Center Kurchatov InstituteCenter Kurchatov Institute
since 1990
Gran Sasso underground laboratory
• Five Ge diodes (overall mass 10.9 kg) Five Ge diodes (overall mass 10.9 kg) isotopically enriched ( 86%) in isotopically enriched ( 86%) in 7676GeGe • Lead box and nitrogen flushing ofLead box and nitrogen flushing of the detectors the detectors • Digital Pulse ShapeDigital Pulse Shape Analysis (factor 5 reductionAnalysis (factor 5 reduction))
FWHM: 4 keVFWHM: 4 keV
0.06 c/keV/kg/y0.06 c/keV/kg/y0.19 c/keV/kg/y0.19 c/keV/kg/y00
22
TT1/21/200 > 1.9 x 10 > 1.9 x 102525 (90 % C.L.) (90 % C.L.)
<m<m> < 0.35 > < 0.35 (0.3-1.24)(0.3-1.24) eV eV
47.7 kg47.7 kg..yy
Accurate background model:Accurate background model:TT1/21/2
22 > (1.55 > (1.55 0.01(stat) 0.01(stat) +0.19+0.19-0.15-0.15 (syst)) x 10 (syst)) x 102121
Klapdor-Kleingrothaus HV et al. Eur. Phys. J. 12 (2001) 147
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 65
Heidelberg-Moscow EvidenceHeidelberg-Moscow EvidenceHeidelberg-Moscow EvidenceHeidelberg-Moscow Evidence
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 66
NNeutrinoless eutrinoless EExperiment withxperiment with MOMOlibdenum libdenum IIIIIIor Nor Neutrinoeutrino E Ettorettore M Majoranaajorana O Observatorybservatory
NNeutrinoless eutrinoless EExperiment withxperiment with MOMOlibdenum libdenum IIIIIIor Nor Neutrinoeutrino E Ettorettore M Majoranaajorana O Observatorybservatory
Large Collaboration: 13 groups from Large Collaboration: 13 groups from EuropeEurope, , USAUSA and and JapanJapan
0022 sensitivity sensitivity: : T ~ 10T ~ 102424 y y
<m<m> ~ 0.1 eV> ~ 0.1 eV
Detector structure: Detector structure: 20 sectors20 sectors1 1 SourceSource: : up to 10 kg of up to 10 kg of isotopes isotopes (metal film or powder glued to mylar strips)(metal film or powder glued to mylar strips)
cylindrical surface: 20 mcylindrical surface: 20 m22 x 40-60 mg/cm x 40-60 mg/cm22
2 2 Tracking volumeTracking volume:: open octagonal drift cells (6180) open octagonal drift cells (6180) operated in Geiger mode operated in Geiger mode ((rr=0.5 mm,=0.5 mm,ZZ=1 cm=1 cm))
3 3 CalorimeterCalorimeter:: 1940 plastic scintillators coupled to low activity PMs: 1940 plastic scintillators coupled to low activity PMs: Magnetic FieldMagnetic Field (30 G) + (30 G) + Iron ShieldIron Shield (20 cm) + (20 cm) + Neutron ShieldNeutron Shield (30 cm H (30 cm H22O)O)
mtot ~ 36 tonsLow activity materials
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 67
NEMO 3NEMO 3 NEMO 3NEMO 3 Now OperatingNow Operating in the Frejus Underground Laboratory: 4800 m.w.e. in the Frejus Underground Laboratory: 4800 m.w.e.
Identification of eIdentification of e--, e, e++, , , n and delayed-, n and delayed-• eventsevents• source radiopuritysource radiopurity• BKG rejectionBKG rejectionby e-by e-, e-, e--- coincidences analysis coincidences analysis
after enrichment and chemical processingafter enrichment and chemical processing
Isotope Mass (g) I.A. Intended
studies<m5y
>
(eV)100Mo 6914 97% (0) 0.2-0.782Se 932 97% (0) 0.6-1.2
116Cd 405 93% (2)130Te 454 89% (2)150Nd 36.6 91% (2)
96Zr 9.4 57% (2)48Ca 7.0 73% (2)natTe 207 Ext. bkgCu 621 Ext. bkg
Enriched sources placed in NEMO3Enriched sources placed in NEMO3
Future results will achieve limits that are more sensitive than WMAP
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 68
Future projectsFuture projectsFuture projectsFuture projectsExperiment Author Isotope Detector description T5y
1/2(y) <m>*
COBRA Zuber 2001 130Te 10 kg CdTe semiconductors 1 x 1024 0.71
CUORICINO Arnaboldi et al 2001 130Te 40 kg of TeO2 bolometers 1.5 x 1025 0.19
NEMO3 Sarazin et al 2000 100Mo 10 kg of bb(0n) isotopes (7 kg Mo) with tracking 4 x 1024 0.56
CUORE Arnaboldi et al. 2001 130Te 760 kg of TeO2 bolometers 7 x 1026 0.027
EXO Danevich et al 2000 136Xe 1 t enriched Xe TPC 8 x 1026 0.052
GEM Zdesenko et al 2001 76Ge 1 t enriched Ge diodes in liquid nitrogen + water shield 7 x 1027 0.018
GENIUS Klapdor-Kleingrothaus et al 2001
76Ge 1 t enriched Ge diodes in liquid nitrogen 1 x 1028 0.015
MAJORANA Aalseth et al 2002 76Ge 0.5 t enriched Ge segmented diodes 4 x 1027 0.025
DCBA Ishihara et al 2000 150Nd 20 kg enriched Nd layers with tracking 2 x 1025 0.035
CAMEO Bellini et al 2001 116Cd 1 t CdWO4 crystals in liquid scintillator > 1026 0.069
CANDLES Kishimoto et al 48Ca several tons of CaF2 crystal in liquid scintillator 1 x 1026
GSO Danevich 2001 160Gd 2 t Gd2SiO5:Ce cristal scintillator in liquid scintillator 2 x 1026 0.065
MOON Ejiri et al 2000 100Mo 34 t natural Mo sheets between plastic scintillator 1 x 1027 0.036
Xe Caccianiga et al 2001 136Xe 1.56 t of enriched Xe in liquid scintillator 5 x 1026 0.066
XMASS Moriyama et al 2001 136Xe 10 t of liquid Xe 3 x 1026 0.086
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 69
Non-Baryonic WimpsNon-Baryonic WimpsNon-Baryonic WimpsNon-Baryonic Wimps
Weakly Interacting Massive Particles (WIMPs)
WIMPS arise in some Supersymmetric (SUSY) theories of particle physics and are the lightest neutral SUSY particle (LSP)
Some SUSY models unify the four forces of physics by adding gravitons and gravitinos (mSUGRA)
WIMPs would have been easily detected in accelerators if M < 15 GeV/c2
The lightest WIMP would be stable, and could still exist in the Universe, contributing most if not all of the Dark Matter
Cross-sections for various interactions can be calculated if the WIMP is assumed to be a neutralino (from mSUGRA for instance).
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 70
Neutralino scatteringNeutralino scatteringNeutralino scatteringNeutralino scattering
Earth based experiments search for evidence for Neutralino-Nucleon scattering, since the Neutralinos permeate the galaxy halo surrounding us (they form the CDM halo).
DAMA has observed a possible signal for WIMPS in a 4 year run. They observe a seasonal variation.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 71
CDMS Upper LimitsCDMS Upper LimitsCDMS Upper LimitsCDMS Upper Limits
Most constraining upper limit of any experiment for WIMPs with 10-70 GeV mass
• EDELWEISS better above 70 GeV
Rules out DAMA NaI/1-4 most likely point (x) at >99.9% CL (for standard WIMPs, halo)
Rules out DAMA NaI/0-4 most likely point (circle) at >99% CL (for standard…)
Compatible with less likely points in DAMA 3σ
allowed regions
X marks DAMA NaI/1-4 most likely point
90% CL upper limits assuming standard halo, A2 scaling
DAMA NaI/1-4 3region
DAMA limit
EDEL
WEI
SS li
mit
Expected CDMS sensitivity
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 72
Compatibility of CDMS and Compatibility of CDMS and DAMADAMA
Compatibility of CDMS and Compatibility of CDMS and DAMADAMA
Likelihood ratio test
• asymptotic approximatios
• “standard” halo
• standard WIMP interactions
CDMS results incompatible with DAMA model-independent annual-modulation data (left) at > 99.99% CL
Best simultaneous fit to CDMS and DAMA predicts too little annual modulation in DAMA, too many events in CDMS (even for small neutron background)
predicted WIMP spectrum with n backgroundCDMS data
n background (1.1 multiples)
predicted WIMP
modulation
DAMA annual modulation data
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 73
EDELWEISS-I, “1kg” stageEDELWEISS-I, “1kg” stageEDELWEISS-I, “1kg” stageEDELWEISS-I, “1kg” stage
ArchaeologicalArchaeological
leadlead
320 g Ge 320 g Ge detectorsdetectors
• Low radioactivity Low radioactivity cryostat cryostat • Shield: Shield: 30 cm paraffin30 cm paraffin 20 cm Pb20 cm Pb 10 cm Cu10 cm Cu
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 74
1kg stage of EDELWEISS-I : 1kg stage of EDELWEISS-I : 3*320 g Ge.3*320 g Ge.
1kg stage of EDELWEISS-I : 1kg stage of EDELWEISS-I : 3*320 g Ge.3*320 g Ge.
• GGA1: GGA1: heat and ionisation Ge heat and ionisation Ge detector detector • aluminium electrodesaluminium electrodes (center + (center + guard ring)guard ring) + + Ge amorphous layerGe amorphous layer • NTD sensor on guard ring electrodeNTD sensor on guard ring electrode• Mass 320 gramMass 320 gram
Resolutions @ 10 keV Resolutions @ 10 keV @ 122 keV)@ 122 keV)• ionisation : 1.3 keVionisation : 1.3 keV 2.2 keV 2.2 keV• heat : heat : 1.0 keV 1.0 keV 3.0 keV 3.0 keV
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 75
CDMS also looks for WIMPSCDMS also looks for WIMPSCDMS also looks for WIMPSCDMS also looks for WIMPS
Cryogenic Dark Matter Search
6.4 million events studied - 13 possible candidates for WIMPs
All are consistent with expected neutron flux
Cryostat holds T= 0.01 K
CDMS Lab 35 feet under Stanford
CDMS has moved to Minnesota Sudan mine (home of MINOS)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 76
Other experiments searching Other experiments searching for WIMPsfor WIMPs
Other experiments searching Other experiments searching for WIMPsfor WIMPs
The DAMA result (CDMS/Edelweiss) limits are for SUSY cross-sections a factor of 10 to 1000 higher than ones that may be of interest for (say) mSUGRA models.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 77
Gamma-ray Large Area Gamma-ray Large Area Space Telescope (GLAST)Space Telescope (GLAST)
Gamma-ray Large Area Gamma-ray Large Area Space Telescope (GLAST)Space Telescope (GLAST)
GLAST Burst Monitor (GBM)
Searches for Neutralino annihilation into gamma rays
Large Area Telescope (LAT)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 78
Overview of LATOverview of LATOverview of LATOverview of LAT
4x4 array of identical towers4x4 array of identical towers Advantages of modular design.
Precision Si-strip Tracker (TKR) Precision Si-strip Tracker (TKR) Detectors and converters arranged in 18 XY tracking planes. Measure the photon direction.
Hodoscopic CsI Calorimeter(CAL)Hodoscopic CsI Calorimeter(CAL) Segmented array of CsI(Tl) crystals. Measure the photon energy.
Segmented Anticoincidence Segmented Anticoincidence Detector (ACD)Detector (ACD) First step in reducing the large background of charged cosmic rays. Segmentation removes self-veto effects at high energy.
Electronics System Electronics System Includes flexible, highly-efficient, multi-level trigger.
Systems work together to identify and Systems work together to identify and measure the flux of cosmic gamma rays measure the flux of cosmic gamma rays
with energy 20 MeV - >300 GeV.with energy 20 MeV - >300 GeV.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 79
GLAST LAT Overview: GLAST LAT Overview: DesignDesign
GLAST LAT Overview: GLAST LAT Overview: DesignDesign
e+ e–
Si Trackerpitch = 228 µm8.8 105 channels12 layers × 3% X0
+ 4 layers × 18% X0
+ 2 layers
Data acquisition
Grid (& Thermal Radiators)
Flight Hardware & Spares16 Tracker Flight Modules + 2 spares16 Calorimeter Modules + 2 spares1 Flight Anticoincidence DetectorData Acquisition Electronics + Flight Software
3000 kg, 650 W (allocation)
1.8 m 1.8 m 1.0 m
20 MeV – >300 GeV
CsI CalorimeterHodoscopic array8.4 X0 8 × 12 bars
2.0 × 2.7 × 33.6 cm shower leakage cosmic-ray rejection correction
ACDSegmented scintillator tiles0.9997 efficiency
minimize self-veto
LAT managed at SLAC
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 80
The next-generation ground-based and space-based experiments are well matched.
Complementary capabilities
ground-based space-based ACT EAS Pairangular resolution good fair goodduty cycle low high higharea large large smallfield of view small large large+can reorient
energy resolution good fair good, w/ smaller systematic uncertainties
Unified gamma ray Unified gamma ray experimental spectrumexperimental spectrum
Unified gamma ray Unified gamma ray experimental spectrumexperimental spectrum
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 81
GLAST & Dark MatterGLAST & Dark MatterGLAST & Dark MatterGLAST & Dark Matter
Constrain cold dark matter candidatesIdentify relatively narrow spectral lines
• Requires energy range with response to at least 300 GeV
• Requires spectral resolution:5% at energies above 10 GeV (goal of 3%)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 82
SUSY WIMPSSUSY WIMPSSUSY WIMPSSUSY WIMPS
WIMPS (Weakly Interacting Massive Particles) include some Supersymmetric Candidates. The fact that WIMPS may or may not have been seen constrains supersymmetric parameters.
LEP limits/ WMAP Limits
Exisiting data already limit some Supersymmetric models to rather narrow windows of opportunity (mSUGRA)
A small window of opportunity exists at FNAL (but it is in the Cosmologically interesting mass range)
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 83
SUSYSUSYSUSYSUSY
Squarks and Gluino mass reach
SUSY (MSUGRA) will be found quickly !
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 84
mSUGRA and WMAPmSUGRA and WMAPmSUGRA and WMAPmSUGRA and WMAP
mSUGRA limits calculated by Daniel Denegri of Saclay for CMS
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 85
SUSY mass measurementSUSY mass measurementSUSY mass measurementSUSY mass measurement
Sharp cutoffs may exist in the invariant mass measurements of certain final states. Such cutoffs are a measure of the mass of a parent SUSY particle
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 86
Consistency with Consistency with CosmologyCosmology
Consistency with Consistency with CosmologyCosmology
J.Ellis et al., hep-ph/0303043
Pre Wmap cosmological constraint 0.1 < h < 0.3 Post Wmap cosmological constraint 0.094 < h < 0.129
is not LSP
2
2
excluded by b -> s favored by g – 2 at 2- level
For the points other than LM1 and LM6, to be in the allowed region(s) requires larger tan …
For the points other than LM1 and LM6, to be in the allowed region(s) requires larger tan …
Slide by Abdullin & Luke after Ellis
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 87
J.Ellis et al., hep-ph/0303043
newer cosmological constraint 0.094 < h < 0.129
2 x
tan from 5 to 55 in steps of 5
tan from 5 to 55 in steps of 5
Approximate values suggested byJ.Ellis :
LM2 : tan = 30
(100 %)(100 %)
LM5 : tan = 50
g b b (80 %),
b b (14 %)
(44 %), (44 %),
b b (17 %)
LM4 : tan = 35
(100 %)(100 %)
LM5 : tan = 45
(98 %)(98 %)
I.e. being in the coannihilation regoin implies a light and hence will
dominate. So we lose the signatures …
I.e. being in the coannihilation regoin implies a light and hence will
dominate. So we lose the signatures …
part compatible with g - 2 at 2 level
Consistency of ParametersConsistency of ParametersConsistency of ParametersConsistency of Parameters
Slide by Abdullin & Luke after Ellis
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 88
Scalar Particle SearchesScalar Particle SearchesScalar Particle SearchesScalar Particle Searches
No scalar particles have been observed• Higgs is a scalar
• Axion is a scalar
• Inflaton is a scalar
One would gain confidence in the existence of Scalar Particles if the Higgs were found at the LHC
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 89
LHC Higgs SearchesLHC Higgs SearchesLHC Higgs SearchesLHC Higgs Searches
3 months (80 fills)
@ L0=1033 cm-2s-1
10fb-1 per expt.
115 GeV
SM Higgs Discovery Reach (5): ATLAS +CMS
AT
LA
S +
CM
S
At L0=1033 cm-2s-1
1 month ~ 0.7 fb-1
At L0= 3.1033 cm-2s-
1
1 month ~ 2 fb-1
Assumptions: 14hr run and 10hr to refill i.e. 1 fill/daytL ~ 20 hr, Efficiency of 2/3
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 90
The LHCThe LHCThe LHCThe LHC
CMS
ATLAS
R = 4.5 KmE = 7+7 TeV (pp)
crossing rate =40MHz (25nsec)
design luminosity = 1034cm-2s-1
~20 pp interactions per crossing at design luminosity
h 4 with 20 min. bias evt.
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 91
Installation of muon chamber
Surface buildings and main shaft
HCAL barrel
HCAL/Muon endcap
Muon barrel yoke
CMS at the CMS at the LHCLHC
CMS at the CMS at the LHCLHC
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 92
Concluding remarks: Concluding remarks: Embarrassment Embarrassment with Dark Energywith Dark Energy
Concluding remarks: Concluding remarks: Embarrassment Embarrassment with Dark Energywith Dark Energy
A naïve estimate of the cosmological constant in Quantum Field Theory: ΩΛ~MPl
4~10120 times observation
The worst prediction in theoretical physics!
If we associate ΩΛ~MΛ4 then MΛ~10-3 eV a number of
the order of the neutrino mass.
Thus we have ΩΛ ~((TeV)2/MPl)4
In a previous decade there were arguments that there must be some mechanism to set ΩΛ to zero
But it is finite, and equal to 0.7
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 93
Quintessense: an Answer ?Quintessense: an Answer ?Quintessense: an Answer ?Quintessense: an Answer ?
Assume that there is a mechanism to set the cosmological constant exactly zero.
The reason for a seemingly finite value is that after 13.7 billion years we haven’t gotten there yet
A scalar field is slowly rolling down its potential towards zero energy
But it has to be extremely light: 10–42 GeV. (Can such a small mass be protected against radiative corrections?) It shouldn’t mediate a “fifth force” , since none have been observed.
Are there other observational consequences of quintessence (in addition to a “small”dark energy density) ? It may “explain” Inflation, but are there predictions of current physical observables ??
Andris Skuja: Marseille Conference 2003, June 23 – 27, 2003 94
Tentative ConclusionsTentative ConclusionsTentative ConclusionsTentative Conclusions
We will continue to be surprised by the neutrino sector. New direct and indirect measurements of neutrino masses will become available soon (comparable to the WMAP resolution). Consistency ?? Will neutrino interactions explain the observed baryon asymmetry ??
The LHC will resolve the CDM mystery (or not) and will have much to say about SUSY in the TeV range. The Higgs may be found.
In conclusion I would like to thank the world community for the slides that I have used. I would also like to apologize to those physicists whose slides I have NOT used due to a lack of time. All of them are contributing to our understanding of the Standard Models of Particle Physics and Cosmology.