${{\mathit \Xi}}$ DECAY PARAMETERS

See the ``Note on Baryon Decay Parameters'' in the neutron Listings.

$\alpha\mathrm {({{\mathit \Xi}^{-}})}{}\alpha _{−}({{\mathit \Lambda}}$) INSPIRE search

OUR FIT value is obtained from measurements of $\alpha\mathrm {({{\mathit \Xi}^{-}})}$, $\alpha _{−}({{\mathit \Lambda}}$), and $\alpha\mathrm {({{\mathit \Xi}^{-}})}{}\alpha _{−}({{\mathit \Lambda}}$).

S022AA

VALUE

EVTS

DOCUMENT ID

TECN

COMMENT

$\bf{ -0.288 \pm0.005}$

OUR FIT Error includes scale factor of 2.2.

$\bf{ -0.294 \pm0.005}$

OUR AVERAGE Error includes scale factor of 1.7.

$-0.2963$ $\pm0.0042$

189k

LUK

2000

E756

${{\mathit p}}$ Be, 800 GeV

$-0.2894$ $\pm0.0073$

63k

LUK

2000

E756

${{\mathit p}}$ Be, 800 GeV

$-0.303$ $\pm0.004$ $\pm0.004$

192k

RAMEIKA

1986

SPEC

400 GeV ${{\mathit p}}{}^{}\mathrm {Be}$

$-0.257$ $\pm0.020$

11k

ASTON

1985

LASS

11 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}{{\mathit p}}$

$-0.260$ $\pm0.017$

21k

BENSINGER

1985

MPS

5 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}{{\mathit p}}$

$-0.299$ $\pm0.007$

150k

BIAGI

1982

SPEC

SPS hyperon beam

$-0.315$ $\pm0.026$

9046

CLELAND

1980

ASPK

BNL hyperon beam

$-0.239$ $\pm0.021$

6599

HEMINGWAY

1978

HBC

4.2 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}{{\mathit p}}$

$-0.243$ $\pm0.025$

4303

BALTAY

1974

HBC

1.75 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}{{\mathit p}}$

$-0.252$ $\pm0.032$

2436

COOL

1974

OSPK

1.8 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}$ ${{\mathit p}}$

$-0.253$ $\pm0.028$

2781

DAUBER

1969

HBC

¹ This LUK 2000 value is for $\alpha\mathrm {({{\overline{\mathit \Xi}}^{+}})}$ $\alpha _{+}({{\overline{\mathit \Lambda}}}$). We assume $\mathit CP$ conservation here by including it in the average for $\alpha\mathrm {({{\mathit \Xi}^{-}})}$ $\alpha _{−}({{\mathit \Lambda}}$). But see the second data block below for the $\mathit CP$ test.

$\alpha\mathrm {({{\mathit \Xi}^{-}})}{}\alpha _{−}({{\mathit \Lambda}}$)

References:

LUK

2000

PRL 85 4860

Search for Direct $\mathit CP$ Violation in Nonleptonic Decays of Charged ${{\mathit \Xi}}$ and ${{\mathit \Lambda}}$ Hyperons

RAMEIKA

1986

PR D33 3172

Measurement of Production Polarization and Decay Asymmetry for ${{\mathit \Xi}^{-}}$ Hyperons

ASTON

1985B

PR D32 2270

Inclusive Production of Multistrange Hyperons from 11 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}$ ${{\mathit p}}$ Interactions

BENSINGER

1985

NP B252 561

Measurement of Decay Parameters and Polarization in Inclusive ${{\mathit \Xi}^{-}}$ Production from ${{\mathit K}^{-}}$ ${{\mathit p}}$ Interactions

BIAGI

1982

PL 112B 265

Determination of the $\alpha $ Parameter for the Decay ${{\mathit \Xi}^{-}}$ $\rightarrow$ ${{\mathit \Lambda}}{{\mathit \pi}^{-}}$

CLELAND

1980C

PR D21 12

Studies in the BNL 21 ${\mathrm {GeV/}}\mathit c$ Negative Hyperon Beam. I. ${{\mathit \Sigma}}$ and ${{\mathit \Xi}}$ Production and Asymmetry in Decay ${{\mathit \Xi}^{-}}$ $\rightarrow$ ${{\mathit \Lambda}}{{\mathit \pi}^{-}}$

HEMINGWAY

1978

NP B142 205

${{\mathit \Omega}^{-}}$ Produced in ${{\mathit K}^{-}}$ ${{\mathit p}}$ Reactions at 4.2 ${\mathrm {GeV/}}\mathit c$

BALTAY

1974

PR D9 49

Properties of ${{\mathit \Xi}^{-}}$ and ${{\mathit \Xi}^{0}}$ Hyperons

COOL

1974

PR D10 792

Measurement of the Magnetic Moment and of the Decay Parameters of the ${{\mathit \Xi}^{-}}$ Hyperon