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${{\mathit \Omega}^{-}}$ MASS

INSPIRE   PDGID:

S024M

The fit assumes the ${{\mathit \Omega}^{-}}$ and ${{\overline{\mathit \Omega}}^{+}}$ masses are the same, and averages them together.

VALUE (MeV) EVTS DOCUMENT ID TECN  COMMENT $\bf{ 1672.45 \pm0.29}$ OUR FIT $\bf{ 1672.43 \pm0.32}$ OUR AVERAGE $1673$ $\pm1$ 100 HARTOUNI 1985 SPEC 80$-$280 GeV ${{\mathit K}_L^0}$ ${}^{}\mathrm {C}$ $1673.0$ $\pm0.8$ 41 BAUBILLIER 1978 HBC 8.25 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}{{\mathit p}}$ $1671.7$ $\pm0.6$ 27 HEMINGWAY 1978 HBC 4.2 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}{{\mathit p}}$ $1673.4$ $\pm1.7$ 4 1 DIBIANCA 1975 DBC 4.9 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}{{\mathit d}}$ $1673.3$ $\pm1.0$ 3 PALMER 1968 HBC ${{\mathit K}^{-}}{{\mathit p}}$ 4.6, 5 ${\mathrm {GeV/}}\mathit c$ $1671.8$ $\pm0.8$ 3 SCHULTZ 1968 HBC ${{\mathit K}^{-}}{{\mathit p}}$ 5.5 ${\mathrm {GeV/}}\mathit c$ $1674.2$ $\pm1.6$ 5 SCOTTER 1968 HBC ${{\mathit K}^{-}}{{\mathit p}}$ 6 ${\mathrm {GeV/}}\mathit c$ $1672.1$ $\pm1.0$ 1 2 FRY 1955 EMUL • • We do not use the following data for averages, fits, limits, etc. • • $1671.43$ $\pm0.78$ 13 3 DEUTSCHMANN 1973 HBC ${{\mathit K}^{-}}{{\mathit p}}$ 10 ${\mathrm {GeV/}}\mathit c$ $1671.9$ $\pm1.2$ 6 3 SPETH 1969 HBC See DEUTSCHMANN 1973 $1673.0$ $\pm8.0$ 1 ABRAMS 1964 HBC $\rightarrow$ ${{\mathit \Xi}^{-}}{{\mathit \pi}^{0}}$ $1670.6$ $\pm1.0$ 1 2 FRY 1955 B EMUL $1615$ 1 4 EISENBERG 1954 EMUL 1  DIBIANCA 1975 gives a mass for each event. We quote the average. 2  The FRY 1955 and FRY 1955B events were identified as ${{\mathit \Omega}^{-}}$ by ALVAREZ 1973 . The masses assume decay to ${{\mathit \Lambda}}{{\mathit K}^{-}}$ at rest. For FRY 1955B, decay from an atomic orbit could Doppler shift the ${{\mathit K}^{-}}$ energy and the resulting ${{\mathit \Omega}^{-}}$ mass by several MeV. This shift is negligible for FRY 1955 because the ${{\mathit \Omega}}$ decay is approximately perpendicular to its orbital velocity, as is known because the ${{\mathit \Lambda}}$ strikes the nucleus (L.Alvarez, private communication 1973). We have calculated the error assuming that the orbital n is 4 or larger. 3  Excluded from the average; the ${{\mathit \Omega}^{-}}$ lifetimes measured by the experiments differ significantly from other measurements. 4  The EISENBERG 1954 mass was calculated for decay in flight. ALVAREZ 1973 has shown that the ${{\mathit \Omega}}$ interacted with an ${}^{}\mathrm {Ag}$ nucleus to give ${{\mathit K}^{-}}{{\mathit \Xi}}{}^{}\mathrm {Ag}$.

References:

HARTOUNI 1985 PRL 54 628 Inclusive Production of ${{\mathit \Omega}^{-}}$ and ${{\overline{\mathit \Omega}}^{+}}$ by ${{\mathit K}_L^0}$ Carbon Interactions in the Energy Range $80 - 280$ ${\mathrm {GeV/}}\mathit c$ BAUBILLIER 1978 PL 78B 342 A Study of the Lifetime and Spin of ${{\mathit \Omega}^{-}}$ Produced in ${{\mathit K}^{-}}{{\mathit p}}$ Interactions at 8.25 ${\mathrm {GeV/}}\mathit c$ HEMINGWAY 1978 NP B142 205 ${{\mathit \Omega}^{-}}$ Produced in ${{\mathit K}^{-}}{{\mathit p}}$ Reactions at 4.2 ${\mathrm {GeV/}}\mathit c$ DIBIANCA 1975 NP B98 137 Study of ${{\mathit \Xi}^{-}}$ and ${{\mathit \Omega}^{-}}$ Production from ${{\mathit K}^{-}}{{\mathit n}}$ and ${{\mathit K}^{-}}{{\mathit p}}$ Interactions at 4.93 ${\mathrm {GeV/}}\mathit c$ DEUTSCHMANN 1973 NP B61 102 ${{\mathit \Omega}^{-}}$ Production in ${{\mathit K}^{-}}{{\mathit p}}$ Interactions SPETH 1969 PL 29B 252 ${{\mathit \Omega}^{-}}$ Production in 10 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}{{\mathit p}}$ Interactions PALMER 1968 PL 26B 323 Precision Measurement of the ${{\mathit \Omega}^{-}}$ and ${{\mathit \Xi}^{0}}$ Masses SCHULTZ 1968 PR 168 1509 Production of ${{\mathit \Omega}^{-}}$ Hyperons in ${{\mathit K}^{-}}{{\mathit p}}$ Interactions at 5.5 ${\mathrm {GeV/}}\mathit c$ SCOTTER 1968 PL 26B 474 ${{\mathit \Omega}^{-}}$ Productions by 6 ${\mathrm {GeV/}}\mathit c$ ${{\mathit K}^{-}}$ Mesons ABRAMS 1964 PRL 13 670 Example of Decay ${{\mathit \Omega}^{-}}$ $\rightarrow$ ${{\mathit \Xi}^{-}}{{\mathit \pi}^{0}}$ FRY 1955B NC 2 346 Further Evidence for Existence of a Heavy ${{\mathit K}^{-}}$ Meson of Heavy Hyperon FRY 1955 PR 97 1189 ${{\mathit K}}$ Mesonic Decay of a Slow Secondary Particle EISENBERG 1954 PR 96 541 Possible Existence of a New Hyperon