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Quark Density $-$ Matter Searches

INSPIRE JSON (beta) PDGID:

QUARKS/ NUCLEON

CHG ${\mathrm {(\mathit e/3)}}$

MASS ${\mathrm {(GeV)}}$

MATERIAL/METHOD

EVTS

DOCUMENT ID

$ \text{<1.17E-22} $

silicone oil drops

0

$ \text{<4.71E-22} $

silicone oil drops

1

$ \text{<4.7E-21} $

$\pm1$,2

silicone oil drops

0

$ \text{<8.E-22} $

$+2$

${}^{}\mathrm {Si}$/infrared photoionization

0

$ \text{<5.E-27} $

$\pm1$,2

sea water/levitation

0

$ \text{<4.E-20} $

$\pm1$,2

meteorites/mag. levitation

0

$ \text{<1.E-19} $

$\pm1$,2

various/spectrometer

0

$ \text{<5.E-22} $

$\pm1$,2

${}^{}\mathrm {W}$/levitation

0

$ \text{<3.E-20} $

$+1$,2

org liq/droplet tower

0

$ \text{<6.E-20} $

$-1$,2

org liq/droplet tower

0

$ \text{<3.E-21} $

$\pm1$

${}^{}\mathrm {Hg}$ drops-untreated

0

$ \text{<3.E-22} $

$\pm1$,2

levitated niobium

0

$ \text{<2.E-26} $

$\pm1$,2

${}^{4}\mathrm {He}$/levitation

0

$ \text{<2.E-20} $

>+-1

$0.2-$250

niobium+tungs/ion

0

$ \text{<1.E-21} $

$\pm1$

levitated niobium

0

$ $

$+1$,2

<100

niobium/mass spec

0

$ \text{<5.E-22} $

levitated steel

0

$ \text{<9.E-20} $

$\pm{}<$13

water/oil drop

0

$ \text{<2.E-21} $

$>\vert \pm1/2\vert $

levitated steel

0

$ \text{<1.E-19} $

$\pm1$,2

photo ion spec

0

$ \text{<2.E-20} $

mercury/oil drop

0

$ \text{1.E-20} $

$+1$

levitated niobium

4

$ \text{1.E-20} $

$-1$

levitated niobium

4

$ \text{<1.E-21} $

levitated steel

0

$ \text{<6.E-16} $

helium/mass spec

0

$ \text{1.E-20} $

$+1$

levitated niobium

2

$ \text{<4.E-28} $

earth+/ion beam

0

$ \text{<5.E-15} $

$+1$

tungs./mass spec

0

$ \text{<5.E-16} $

$+3$

<1.7

hydrogen/mass spec

0

$ \text{<1.E-21} $

$\pm2$,4

water/ion beam

0

$ \text{<6.E-15} $

$>$1/2

levitated tungsten

0

$ \text{<1.E-22} $

metals/mass spec

0

$ \text{<5.E-15} $

levitated tungsten ox

0

$ \text{<3.E-21} $

levitated iron

0

$ \text{2.E-21} $

$-1$

levitated niobium

1

$ \text{4.E-21} $

$+1$

levitated niobium

2

$ \text{<1.E-13} $

$+3$

<7.7

hydrogen/mass spec

0

$ \text{<5.E-27} $

water+/ion beam

0

$ \text{<1.E-21} $

lunar+/ion spec

0

$ \text{<1.E-15} $

$+1$

<60

oxygen+/ion spec

0

$ \text{<5.E-19} $

levitated graphite

0

$ \text{<5.E-23} $

water+/atom beam

0

$ \text{<1.E-17} $

$\pm1$,2

levitated graphite

0

$ \text{<1.E-17} $

water+/uv spec

0

$ \text{<3.E-19} $

$\pm1$

levitated iron

0

$ \text{<1.E-10} $

sun/uv spec

0

$ \text{<1.E-17} $

$+1$,2

meteorites+/ion beam

0

$ \text{<1.E-16} $

$\pm1$

levitated graphite

0

$ \text{<1.E-22} $

argon/electrometer

0

$ $

$-2$

levitated oil

0

¹	95$\%$ CL limit for fractional charge particles with 0.18$\mathit e{}\leq{}\vert Q_{residual}\vert {}\leq{}0.82\mathit e$ in total of 70.1 mg of silicone oil.

²	95$\%$ CL limit for particles with fractional charge $\vert Q_{residual}\vert >$0.16e in total of 17.4~mg of silicone oil.

³	Also set limits for $\mathit Q$ = $\pm{}\mathit e$/6.

⁴	Note that in PHILLIPS 1988 these authors report a subtle magnetic effect which could account for the apparent fractional charges.

⁵	Limit inferred by JONES 1977B.

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