1 Experimental and Theoretical Mysteries of Mass: A View From A Contrarian Experimenter Martin L....

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Experimental andTheoretical

Mysteries of Mass:A View From A

Contrarian Experimenter

Martin L. PerlStanford Linear Accelerator [email protected]

• This is the best time for doing physics that I have experienced in my lifetime. We have better technology in particle physics and astronomy. We are more open to new thoughts.

• This talk is string theory neutral because my understanding of the theory is at the levelof the first half of Zweiback's “First Course in String Theory “.

• References are limited

mailto:[email protected]

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Mass of known particles

Mass mechanismsWhy are the mass ratios so peculiar?

Is there a mass scale?

Large mass and Planck mass

Supersymmetric particles

Dark matter

Monopoles

Energy reach of colliders

Mass reach in astronomy

Mass reach of searches in bulk materials

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Particle Mass GeV/c2

1018

1015

1012

109

106

103

100

10-3

10-6

10-9

10-12

10-15M< 6×10-26 (see next page}

[1 eV/c2]

Masses of the known elementary particles

MPlanck

t

bcs

u, d[1 MeV/c2]

[1 GeV/c2]

[1 TeV/c2]

e

W, Z

1

2

3One masscould be 0

4

Aside on photon mass

M< 6×10-26 GeV/c2 is based on a magnetohydrodynamic

study of solar wind, D. D. Ryutov, Plasma Phys. Control

Fusion, 39, A73 (1997). I don’t understand the physics.

M< 7×10-28 GeV/c2 based on a torsion balance method by

J. Luo et al. , Phys. Rev. Lett., 90, 081801-1 (2003) but

Is disputed by A. S. Goldhaber and M. M. Nieto, Phys. Rev.

Lett., 91, 149101-1 (2003). They prefer

M< 1×10-26 GeV/c2 based on a torsion balance method by

J. Lakes , Phys. Rev. Lett., 80, 1826 (1998)

Review on photon mass:

L-C. Tu, J. Luo, G. T,Gillies, Rept. Prog. Phys., 68, 77

(2005)

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Dark matter

Monopoles




6

Mystery 1We have multiple models for the physics underlying theHiggs mechanism and othermass mechanisms.

,W,

Z

u, d, c, s, t, b

e, ,

Straightforward Higgsmechanism but what isunderlying physics?

Higgs mechanism butdo not know how tocalculate each fermion’scoupling to Higgs. WhatIs underlying physics?

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Usual mechanism issee-saw with initial Higgs mechanism foreach neutrino.

Kaluza-Kleinparticles

Many mechanismsproposed

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Mystery 2Why are the mass ratios sopeculiar?

Peculiar mass ratios:

me : m:m = 1:207:3477

mt / mu ~ 8 x 104

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Dark matter

Monopoles




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Mystery 3Is there a mass scale?

The mass range of the known particles islimited by our technology. We know whatzero mass is, but we do not know what isa large mass?

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Dark matter

Monopoles




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Mystery 4My problem with the Planck mass.

2Planckhc

MG

MPlanck=2.2 x 10-8 kg = 1.2 x 1019 GeV/c2

My problems:

• MPlanck mixes a constant from quantum•mechanics with two classical constants.

• The masses of known particles havenothing to do with their forces.

• Does MPlanck have anything to do withelementary particle masses?

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Mystery 4 continuedMy problem with the Planck mass.

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2Planckhc

EG

EPlanck=2.0 x 109 J = 1.2 x 1019 GeV

Perhaps it is better to think of the PlanckEnergy as the point where quantummechanics intersects with gravity, and notglibly equate energy with mass.

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Dark matter

Monopoles




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Mystery 5Supersymmetry, yes or no?

I am optimistic that the question of the existence of supersymmetric particleswill be settled by the Large Hadron Collider and the e+e- Linear Collider

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Dark matter

Monopoles




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Mystery 6Nature of dark matter

Courtesy of Blas Cabrera

Usual assumption is 10<Mdark matter<104 GeV/c2

1. Collider and Direct Searches

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Mystery 6 continuedNature of dark matter

2. Indirect Searches for Signals from Space

X X e e

X X p p

X X

X X

Some weak evidence from HEAT balloon measurementsfor excess of positrons in cosmic rays.

Center of sun may be a special source.

J. Carr, G. Lamanna, and J. Lavelle, Rep, Prog. Phys. 69, 2475 (2006)

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Dark matter

Monopoles




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Mystery 7Where are the monopoles?

Mmonopole> about 400 GeV/c2 from searches at Tevatron

A. Abulencia et al., Phys. Rev. Lett., 96 , 201801-1

(2006) ; (direct search for heavy ionization)

G. R. Kalbfleisch et al., Phys. Rev., D69,052002-1

(2004) : ( search for monopoles in detector parts)

Reviews:

K. A. Milton, Rept. Prog. Phys., 69, 1637 (2008)

M. Fairbairn et al., hep-ph/0611040v2 (Also general

reference for massive stable particles.)

1. Colliders

Many hypothesis about Mmonopole. There used to be

interest in so-called GUT Monopole with M~1017GeV/c2,

seems to have died off.

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Mystery 7 continuedWhere are the monopoles?

Macro experiment searched for Mmonopole> 1010 GeV/c2 ,

found flux < about 10-16 /cm2 s sr

M. Ambrosio et al., Eur. Phys. J., C25 , 511 (2002)

Extended Parker Bound on monopole flux

F<5 x 10-21 (Mmonopole/1017GeV/c2)/cm2 s sr

M. J. Lewis, K. Freese, and G. Tarle, Phys. Rev.,D62,

025002 (2000)

2. From outer space

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Dark matter

Monopoles




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CMS energyin TeV

1000

100

10

1

e+e-

colliderµ+µ-

collider

LHC

Energy reach of colliderswith ‘known’ technology

VLHCEcms=200 TeV

F. Zimmerman, Int. J. Mod. Phys. A21, 1987 (2006)S. Tazzari and M. Ferrario, Rep. Prog. Phys. 66,1045 (2003)

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Direct and indirect massreach of colliders with‘known’ technology

Particle

soughtZ’ q* L

(4th gen.)

Extra-

dim.

4 TeV

e+e-

+-

20 4 2 ~50

14 TeV

LHC

5 6 6 ~10

200

TeV

VLHC

40 80 30 ~50

Mass in TeV/c2

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We look forward to colliderswith advanced technology

Require:

Large gradientsVery small beamsGood power efficiencyReasonable cost

Advanced technologies:

Laser driven plasma wakefield acceleration

Beam driven plasma wakefield acceleration

Dielectric wakefield acceleration

Vacuum laser acceleration

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Dark matter

Monopoles




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Mystery 8Mass reach in astronomy

Thermal relics from early universe

Mass up to ~300 TeV/c2

K. Griest and M. Kamionkowski, Phys. Rev. Lett. 64, 615 (1990)

Non-thermal relics produced after inflation

Mass up to ~ 1013 TeV/c2

D. J. H. Chung et al., Phys.Rev.D59, 023501(1999)

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Dark matter

Monopoles




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Searches for X+ in water, bylooking for HXO in H2O

Use electrolysis, ultracentrifuge, etc.to concentrate HXO. Then

P. Verkerk et. al.Phys. Rev. Lett. 68, 1116(1992)

T. K. Hemmick et. al.Phys. Rev. D41, 2074(1990)

P. F. Smith et.al.Nucl.Phys. B206, 333(1982)

use mass spectrometer or spectralanalysis to look for HXO

MHXO

MH 02

_____

concentrationratio

General review: M. L. Perl et al., Int. J. Mod. Phys. A16,2137 (2001)

________________________________________________

Mystery 9Mass reach of searches in

bulk matter for stable particles

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Searches for X in Nuclei

-

X in small Bohr orbit-

Nucleus Z

= Z-1, super heavy isotope

Searches in Li, Be, Bo, C, O, F, Na

Searches up to MX ~ 105 GeV/c2

No super heavy isotopes found

T. K. Hemmick et. al.Phys. Rev. D41, 2074(1990)

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I cannot find a way to search for amassive stable charged particle X insolid material

-

X has mass MX and charge E

Coulomb binding energy ~ 1 eV ~ 10-19

and extends ~10-10 m

Therefore Coulomb binding force FB~10-9 nt

X stays in solid if MX<FB/g ~10-10 kg~1017 GeV/c2

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Search would extend to even largerMX on an asteroid.

I published a method using liquids drops that will not work [Phys. Rev. D57,4441 (1998)]

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