pdgLive

Quark Flux $-$ Accelerator Searches

INSPIRE JSON (beta) PDGID:

The definition of FLUX depends on the experiment

(a)	is the ratio of measured free quarks to predicted free quarks if there is no “confinement.''

(b)	is the probability of fractional charge on nuclear fragments. Energy is in GeV/nucleon.

(c)	is the 90$\%$CL upper limit on fractionally-charged particles produced per interaction.

(d)	is quarks per collision.

(e)	is inclusive quark-production cross-section ratio to ${\mathit \sigma (}{{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}{)}$.

(f)	is quark flux per charged particle.

(g)	is the flux per ${{\mathit \nu}}$-event.

(h)	is quark yield per ${{\mathit \pi}^{-}}$ yield.

(i)	is 2-body exclusive quark-production cross-section ratio to ${\mathit \sigma (}{{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}{)}$.

FLUX

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

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

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

BEAM

EVTS

DOCUMENT ID

TECN

$ \text{<1.6E-3} $

b

see note

$200$

${}^{32}\mathrm {S}-{}^{}\mathrm {Pb}$

0

PLAS

$ \text{<6.2E-4} $

b

see note

$10.6$

${}^{32}\mathrm {S}-{}^{}\mathrm {Pb}$

0

PLAS

$ \text{<0.94E-4} $

e

$\pm2$

$2 - 30$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

OPAL

$ \text{<1.7E-4} $

e

$\pm2$

$30 - 40$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

OPAL

$ \text{<3.6E-4} $

e

$\pm4$

$5 - 30$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

OPAL

$ \text{<1.9E-4} $

e

$\pm4$

$30 - 45$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

OPAL

$ \text{<2.E-3} $

e

$+1$

$5 - 40$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ALEP

$ \text{<6.E-4} $

e

$+2$

$5 - 30$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ALEP

$ \text{<1.2E-3} $

e

$+4$

$15 - 40$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ALEP

$ \text{<3.6E-4} $

i

$+4$

$5.0 - 10.2$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ALEP

$ \text{<3.6E-4} $

i

$+4$

$16.5 - 26.0$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ALEP

$ \text{<6.9E-4} $

i

$+4$

$26.0 - 33.3$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ALEP

$ \text{<9.1E-4} $

i

$+4$

$33.3 - 38.6$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ALEP

$ \text{<1.1E-3} $

i

$+4$

$38.6 - 44.9$

$88 - 94$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ALEP

$ \text{<1.6E-4} $

b

see note

see note

0

PLAS

$ \text{} $

b

4,5,7,8

$2.1$A

${}^{16}\mathrm {O}$

0,2,0,6

EMUL

$ \text{<6.4E-5} $

g

1

${{\mathit \nu}},{{\overline{\mathit \nu}}}$

1

CNTR

$ \text{<3.7E-5} $

g

2

${{\mathit \nu}},{{\overline{\mathit \nu}}}$

0

CNTR

$ \text{<3.9E-5} $

g

1

${{\mathit \nu}},{{\overline{\mathit \nu}}}$

1

CNTR

$ \text{<2.8E-5} $

g

2

${{\mathit \nu}},{{\overline{\mathit \nu}}}$

0

CNTR

$ \text{<1.9E-4} $

c

$14.5$A

${}^{28}\mathrm {Si}-$Pb

0

PLAS

$ \text{<3.9E-4} $

c

$14.5$A

${}^{28}\mathrm {Si}-$Cu

0

PLAS

$ \text{<1.E-9} $

c

$\pm1$,2,4

$14.5$A

${}^{16}\mathrm {O}-$Ar

0

MDRP

$ \text{<5.1E-10} $

c

$\pm1$,2,4

$14.5$A

${}^{16}\mathrm {O}-$Hg

0

MDRP

$ \text{<8.1E-9} $

c

$\pm1$,2,4

$14.5$A

Si$-$Hg

0

MDRP

$ \text{<1.7E-6} $

c

$\pm1$,2,4

60A

${}^{16}\mathrm {O}-$Hg

0

MDRP

$ \text{<3.5E-7} $

c

$\pm1$,2,4

200A

${}^{16}\mathrm {O}-$Hg

0

MDRP

$ \text{<1.3E-6} $

c

$\pm1$,2,4

200A

S$-$Hg

0

MDRP

$ \text{<5E-2} $

e

2

$19 - 27$

$52 - 60$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

TOPZ

$ \text{<5E-2} $

e

4

$<$24

$52 - 60$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

TOPZ

$ \text{<1.E-4} $

e

$+2$

<3.5

$10$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

CLEO

$ \text{<1.E-6} $

d

$\pm1$,2

$60$

${}^{16}\mathrm {O}-$Hg

0

MDRP

$ \text{<3.5E-7} $

d

$\pm1$,2

$200$

${}^{16}\mathrm {O}-$Hg

0

MDRP

$ \text{<1.3E-6} $

d

$\pm1$,2

$200$

${}^{}\mathrm {S}-$Hg

0

MDRP

$ \text{<1.2E-10} $

d

$\pm1$

$1$

$800$

${{\mathit p}}-{}^{}\mathrm {Hg}$

0

MDRP

$ \text{<1.1E-10} $

d

$\pm2$

$1$

$800$

${{\mathit p}}-{}^{}\mathrm {Hg}$

0

MDRP

$ \text{<1.2E-10} $

d

$\pm1$

$1$

$800$

${{\mathit p}}-{}^{}\mathrm {N}_{2}$

0

MDRP

$ \text{<7.7E-11} $

d

$\pm2$

$1$

$800$

${{\mathit p}}-{}^{}\mathrm {N}_{2}$

0

MDRP

$ \text{<6.E-9} $

h

$-5$

$0.9 - 2.3$

$12$

${{\mathit p}}$

0

SPEC

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

g

1,2

<0.5

${{\mathit \nu}},{{\overline{\mathit \nu}}}{{\mathit d}}$

0

BEBC

$ \text{<3.E-4} $

b

See note

$14.5$

${}^{16}\mathrm {O}-{}^{}\mathrm {Pb}$

0

PLAS

$ \text{<2.E-4} $

b

See note

$200$

${}^{16}\mathrm {O}-{}^{}\mathrm {Pb}$

0

PLAS

$ \text{<8E-5} $

b

19,20,22,23

200$\mathit A$

PLAS

$ \text{<2.E-4} $

a

$\pm1$,2

<300

$320$

${{\overline{\mathit p}}}{{\mathit p}}$

0

MLEV

$ \text{<1.E-9} $

c

$\pm1$,2,4,5

$14.5$

${}^{16}\mathrm {O}-{}^{}\mathrm {Hg}$

0

MDRP

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

d

$-1$,2,3,4,6

<5

$2$

${}^{}\mathrm {Si}-{}^{}\mathrm {Si}$

0

CNTR

$ \text{<1.E-4} $

e

$\pm1$,2,4

<4

$10$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

ARG

$ \text{<6.E-5} $

b

$\pm1$,2

1

$540$

${{\mathit p}}{{\overline{\mathit p}}}$

0

UA2

$ \text{<5.E-3} $

e

$-4$

1$-$8

$29$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

TPC

$ \text{<1.E-2} $

e

$\pm1$,2

1$-$13

$29$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

TPC

$ \text{<2.E-4} $

b

$\pm1$

$72$

${}^{40}\mathrm {Ar}$

0

CNTR

$ \text{<1.E-4} $

e

$\pm2$

<0.4

$1.4$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

OLYA

$ \text{<5.E-1} $

e

$\pm1$,2

<13

$29$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

CNTR

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

b

$\pm1$,2

<2

$540$

${{\mathit p}}{{\overline{\mathit p}}}$

0

CNTR

$ \text{<1.E-4} $

b

$\pm1$,2

$106$

${}^{56}\mathrm {Fe}$

0

CNTR

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

b

$>\vert \pm0.1\vert $

$74$

${}^{40}\mathrm {Ar}$

0

PLAS

$ \text{<1.E-2} $

e

$\pm1$,2

<14

$29$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

CNTR

$ \text{<8.E-2} $

e

$\pm1$,2

<12

$29$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

CNTR

$ \text{<3.E-4} $

e

$\pm2$

$1.8-$2

$7$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

MRK2

$ \text{<5.E-2} $

e

$+1$,2,4,5

2$-$12

$27$

${{\mathit e}^{+}}{{\mathit e}^{-}}$

0

JADE

$ \text{<2.E-5} $

g

$1$,2

${{\mathit \nu}}$

0

CNTR

$ \text{<3.E-10} $

f

$\pm2$,4

1$-$3

$200$

${{\mathit p}}$

0

CNTR

$ \text{<6.E-11} $

f

$\pm1$

<21

$52$

${{\mathit p}}{{\mathit p}}$

0

SPEC

$ \text{<5.E-3} $

g

${{\mathit \nu}_{{{\mu}}}}$

0

CNTR

$ \text{<2.E-9} $

f

$\pm1$

<26

$62$

${{\mathit p}}{{\mathit p}}$

0

SPEC

$ \text{<7.E-10} $

f

$+1$,2

<20

$52$

${{\mathit p}}$

0

CNTR

$ $

$+1$,2

>4.5

${{\mathit \gamma}}$

0

CNTR

$ $

$+1$,2

>1.5

$12$

${{\mathit e}^{-}}$

0

CNTR

$ $

$+1$,2

>0.9

${{\mathit \gamma}}$

0

CNTR

$ $

$+1$,2

>0.9

$6$

${{\mathit \gamma}}$

0

CNTR

¹	HUENTRUP 1996 quote 95$\%$ CL limits for production of fragments with charge differing by as much as $\pm1$/3 (in units of e) for charge 6${}\leq{}Z{}\leq{}$10.

²	BUSKULIC 1993C limits for inclusive quark production are more conservative if the ALEPH hadronic fragmentation function is assumed.

³	CECCHINI 1993 limit at 90$\%$CL for 23/3 ${}\leq{}Z{}\leq{}$40/3, for 16$\mathit A$ GeV O, 14.5$\mathit A$ Si, and 200$\mathit A$ S incident on Cu target. Other limits are $2.3 \times 10^{-4}$ for 17/3${}\leq{}Z{}\leq{}$20/3 and $1.2 \times 10^{-4}$ for 20/3 ${}\leq{}Z{}\leq{}$23/3.

⁴	GHOSH 1992 reports measurement of spallation fragment charge based on ionization in emulsion. Out of 650 measured tracks, 2 were consistent with charge 5${{\mathit e}}$/3, and 4 with 7${{\mathit e}}$/3.

⁵	Hadronic quark.

⁶	Leptonic quark.

⁷	HE 1991 limits are for charges of the form $\mathit N\pm1$/3 from 23/3 to 38/3, and correspond to cross-section limits of 380$\mu $b$~$(Pb) and 320$\mu $b$~$(Cu).

⁸	The limits apply to projectile fragment charges of 17, 19, 20, 22, 23 in units of $\mathit e$/3.

⁹	The limits apply to projectile fragment charges of 16, 17, 19, 20, 22, 23 in units of $\mathit e$/3.

¹⁰	Flux limits and mass range depend on charge.

¹¹	Bound to nuclei.

¹²	Quark lifetimes $>1 \times 10^{-8}$ s.

¹³	One candidate $\mathit m$ $<$0.17 GeV.

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