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${{\mathit \Lambda}_{{b}}^{0}}$ MASS

${\mathit m}_{{{\mathit \Lambda}_{{b}}^{0}}}$

INSPIRE   PDGID:

S040M

VALUE (MeV) EVTS DOCUMENT ID TECN  COMMENT $\bf{ 5619.60 \pm0.17}$ OUR AVERAGE $5619.62$ $\pm0.16$ $\pm0.13$ 1 AAIJ 2017 AM LHCB ${{\mathit p}}{{\mathit p}}$ at 7, 8 TeV $5619.30$ $\pm0.34$ 2 AAIJ 2014 AA LHCB ${{\mathit p}}{{\mathit p}}$ at 7 TeV $5620.15$ $\pm0.31$ $\pm0.47$ 3 AALTONEN 2014 B CDF ${{\mathit p}}{{\overline{\mathit p}}}$ at 1.96 TeV $5619.7$ $\pm0.7$ $\pm1.1$ 3 AAD 2013 U ATLS ${{\mathit p}}{{\mathit p}}$ at 7 TeV $5621$ $\pm4$ $\pm3$ 4 ABE 1997 B CDF ${{\mathit p}}{{\overline{\mathit p}}}$ at $1.8$ TeV $5668$ $\pm16$ $\pm8$ 4 5 ABREU 1996 N DLPH ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$ $5614$ $\pm21$ $\pm4$ 4 5 BUSKULIC 1996 L ALEP ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$ • • We do not use the following data for averages, fits, limits, etc. • • $5619.65$ $\pm0.17$ $\pm0.17$ 6 AAIJ 2016 Y LHCB Repl. by AAIJ 2017AM $5619.44$ $\pm0.13$ $\pm0.38$ 3 AAIJ 2013 AV LHCB Repl. by AAIJ 2017AM $5619.19$ $\pm0.70$ $\pm0.30$ 3 AAIJ 2012 E LHCB Repl. by AAIJ 2013AV $5619.7$ $\pm1.2$ $\pm1.2$ 7 ACOSTA 2006 CDF Repl. by AALTONEN 2014B not seen 8 ABE 1993 B CDF Repl. by ABE 1997B $5640$ $\pm50$ $\pm30$ 16 9 ALBAJAR 1991 E UA1 ${{\mathit p}}{{\overline{\mathit p}}}$ 630 GeV $5640$ ${}^{+100}_{-210}$ 52 BARI 1991 SFM ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\mathit D}^{0}}{{\mathit \pi}^{-}}$ $5650$ ${}^{+150}_{-200}$ 90 BARI 1991 SFM ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{-}}$ 1  Uses ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit \chi}_{{c1}}}{{\mathit p}}{{\mathit K}^{-}}$ , ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit \chi}_{{c2}}}{{\mathit p}}{{\mathit K}^{-}}$ , ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \Lambda}}$ , ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \psi}{(2S)}}{{\mathit K}^{-}}$ , ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\mathit J / \psi}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit K}^{-}}$ , and ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\mathit J / \psi}}{{\mathit K}^{-}}$ decays. 2  Uses exclusively reconstructed final states ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit D}_{{s}}^{-}}$ , ${{\mathit \Lambda}_{{c}}^{+}}{{\mathit D}^{-}}$ and ${{\overline{\mathit B}}^{0}}$ $\rightarrow$ ${{\mathit D}^{+}}{{\mathit D}_{{s}}^{-}}$ decays. The uncertainty includes both statistical and systematic contributions. 3  Uses ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \Lambda}}$ fully reconstructed decays. 4  ABE 1997B observed 38 events with a background of $18$ $\pm1.6$ events in the mass range $5.60 - 5.65$ ${\mathrm {GeV/}}\mathit c{}^{2}$, a significance of $>3.4$ standard deviations. 5  Uses 4 fully reconstructed ${{\mathit \Lambda}_{{b}}}$ events. 6  Uses ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\mathit \psi}{(2S)}}{{\mathit K}^{-}}$ , ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\mathit J / \psi}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit K}^{-}}$ , and ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\mathit J / \psi}}{{\mathit K}^{-}}$ decays. 7  Uses exclusively reconstructed final states containing a ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ decays. 8  ABE 1993B states that, based on the signal claimed by ALBAJAR 1991E, CDF should have found $30$ $\pm23$ ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}{(1S)}}{{\mathit \Lambda}}$ events. Instead, CDF found not more than 2 events. 9  ALBAJAR 1991E claims $16$ $\pm5$ events above a background of $9$ $\pm1$ events, a significance of about 5 standard deviations.

References:

AAIJ 2017AM PRL 119 062001 Observation of the Decays ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit \chi}_{{c1}}}{{\mathit p}}{{\mathit K}^{-}}$ and ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit \chi}_{{c2}}}{{\mathit p}}{{\mathit K}^{-}}$ AAIJ 2016Y JHEP 1605 132 Observation of ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit \psi}{(2S)}}{{\mathit p}}{{\mathit K}^{-}}$ and ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit p}}{{\mathit K}^{-}}$ Decays and a Measurement of the ${{\mathit \Lambda}_{{b}}^{0}}$ Baryon Mass AAIJ 2014AA PRL 112 202001 Study of Beauty Hadron Decays into Pairs of Charm Hadrons AALTONEN 2014B PR D89 072014 Mass and Lifetime Measurements of Bottom and Charm Baryons in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions at $\sqrt {s }$ = 1.96 TeV AAD 2013U PR D87 032002 Measurement of the ${{\mathit \Lambda}_{{b}}^{0}}$ Lifetime and Mass in the ATLAS Experiment AAIJ 2013AV PRL 110 182001 Measurement of the ${{\mathit \Lambda}_{{b}}^{0}}$, ${{\mathit \Xi}_{{b}}^{-}}$ and ${{\mathit \Omega}_{{b}}^{-}}$ Baryon Masses AAIJ 2012E PL B708 241 Measurement of ${\mathit {\mathit b}}$-Hadron Masses ACOSTA 2006 PRL 96 202001 Measurement of Bottom-Quark Hadron Masses in Exclusive ${{\mathit J / \psi}}$ Decays with the CDF Detector ABE 1997B PR D55 1142 Observation of ${{\mathit \Lambda}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \Lambda}}$ at the Fermilab Proton Antiproton Collider ABREU 1996N PL B374 351 Search for Exclusive Decays of the ${{\mathit \Lambda}_{{b}}}$ Baryon and Measurement of its Mass BUSKULIC 1996L PL B380 442 Measurement of the Mass of the ${{\mathit \Lambda}_{{b}}}$ Baryon ABE 1993B PR D47 2639 Search for ${{\mathit \Lambda}_{{b}}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \Lambda}^{0}}$ in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions at $\sqrt {s }$ = 1.8 TeV ALBAJAR 1991E PL B273 540 First Observation of the Beauty Baryon ${{\mathit \Lambda}_{{b}}}$ in the Decay Channel ${{\mathit \Lambda}_{{b}}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit \Lambda}}$ at the CERN Proton-Antiproton Collider BARI 1991 NC 104A 1787 The ${{\mathit \Lambda}_{{b}}^{0}}$ Beauty Baryon Production in Proton Proton Interactions at $\sqrt {s }$ = 62 GeV: a Second Observation

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