HEPData Search

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Observation of orbitally excited B mesons

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.

Phys.Lett.B 345 (1995) 598-608, 1995.

Inspire Record 382208 DOI 10.17182/hepdata.48321

Experimental evidence for the existence of orbitally excited B meson states is presented in an analysis of the Bπ and B ∗ π distribution of Q = m(B ∗∗ ) − m(B (∗) ) − m(π) using Z 0 decay data taken with the DELPHI detector at LEP. The mean Q-value of the decays B ∗∗ → B (∗) π is measured to be 284 ± 5 (stat.) ± 15 (syst.) MeV/c 2 , and the Gaussian width of the signal is 79 ± 5 (stat.) ± 8 (syst.) MeV/c 2 . This signal can be described as a single resonance of mass m = 5732 ± 5 (stat.) ± 20 (syst.) MeV/c 2 and full width Γ = 145 ± 28 MeV/c 2 . The observed shape is also consistent with the production of several broad and narrow states as predicted by the quark model and partly observed in the D-meson sector. The production rate of B ∗∗ per b-jet is found to be 0.27 ± 0.02 (stat.) ± 0.06 (syst.).

1 data table

Table 1

No description provided.

Measurement of the Branching Ratio for $\Xi^- \to \Sigma^- \gamma$ Radiative Decay

The E761 collaboration Dubbs, T. ; Albuquerque, I.F. ; Bondar, N.F. ; et al.

Phys.Rev.Lett. 72 (1994) 808-811, 1994.

Inspire Record 358245 DOI 10.17182/hepdata.18430

We have measured the branching ratio for the hyperon radiative decay Ξ−→Σ−γ from a sample of 211±33 events obtained in the polarized 375 GeV/c charged hyperon beam at Fermilab. We find B(Ξ−→Σ−γ/Ξ−→Λ0π−)=(1.22±0.23±0.06)×10−4 where the quoted errors are statistical and systematic, respectively. We have also obtained an indication that the sign of the asymmetry parameter of this decay is positive.

1 data table

Table 1

Polarized 375 GeV charged hyperon beam at Fermilab. Sample of 211 +- 33 events.

$\Sigma(c$)++ and $\Sigma(c$)0 Production From $e^+ e^-$ Annihilation in the $\Upsilon$ Energy Region

The CLEO collaboration Bowcock, T.J.V. ; Kinoshita, K. ; Pipkin, F.M. ; et al.

Phys.Rev.Lett. 62 (1989) 1240, 1989.

Inspire Record 25467 DOI 10.17182/hepdata.47269

We have observed Σc++ and Σc0 baryons in nonresonant e+e− interactions through their decays to Λc+π± using the CLEO detector. The mass difference M(Σc++)-M(Λc+) is measured to be 167.8±0.4±0.3 MeV; for M(Σc0)-M(Λc+) we find 167.9±0.5±0.3 MeV. Σc decay accounts for (18±3±5)% of Λc+ production.

2 data tables

Table 1

The cross section ratio is multiplied by a factor of 1.5 to account for theunobserved SIGMA/C(2455)+.

Table 2

No description provided.

FRAGMENTATION INTO STRANGE PARTICLES IN HIGH-ENERGY NEUTRINO P, neutrino N, ANTI-NEUTRINO P AND ANTI-NEUTRINO N INTERACTIONS

The AMSTERDAM-BERGEN-BOLOGNA-PADUA-PISA-SACLAY-TURIN collaboration Allasia, D. ; Angelini, C. ; Baldini, A. ; et al.

Phys.Lett.B 154 (1985) 231-235, 1985.

Inspire Record 218756 DOI 10.17182/hepdata.30415

The fragmentation of the hadronic system into Λ, Σ(1385), K ) and K ∗ (892) in deep-inelastic charged-current interactions of high energy neutrinos and antineutrinos with proton and neutron is analyzed. The results obtained for the production of these particles from the various initial states are compared with each other and with the predictions of the Lund fragmentation model. This comparison shows that a spectator diquark does not fragment as a whole in a fraction of the interactions. The role of the sea quarks in the baryon formation process is underlined. Strange vector and pseudoscalar mesons are likely to be produced at similar rates.

3 data tables

Table 1

No description provided.

Table 2

SIG(C=LAMBDA) denotes the inclusive LAMBDA production in the same reaction.

Table 3

SIG(C=KS) denotes the inclusive KS production in the same reaction.

Measurement of the Relative Total Hadronic Cross-section R at {PETRA}

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Boehm, A. ; et al.

Phys.Rev.Lett. 42 (1979) 1113, 1979.

Inspire Record 140059 DOI 10.17182/hepdata.3235

We report the first measurement of the ratio R=(σe+e−→hadrons)(σe+e−→μ+μ−) (with negligible τ-lepton contribution) at a center-of-mass energy s=13 GeV and s=17 GeV, from the just finished electron-positron colliding-beam facility PETRA. The detector, MARK-J, has an approximately 4π solid angle and measures γ, e, μ, and charged and neutral hadrons simultaneously. Our results yield R(s=17 GeV)=4.9±0.6 (statistical) ±0.7 (systematic error), and R(s=13 GeV)=4.6±0.5 (statistical) ±0.7 (systematic error). The ratio R(s=17 GeV)R(s=13 GeV) is 1.08±0.18.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Reaction $\pi^- p \to \eta n$ in the 15-{GeV}/$c$ to 40-{GeV}/$c$ Momentum Range

The Serpukhov-CERN collaboration Apel, W.D. ; Augenstein, K.H. ; Bertolucci, E. ; et al.

Nucl.Phys.B 152 (1979) 1, 1979.

Inspire Record 133409 DOI 10.17182/hepdata.41487

A high-statistics measurement of the reaction π − p→ η n; η →2 γ has been performed at the 70 GeV Serpukhov accelerator for 15, 20, 25, 30 and 40 GeV/ c incident pion momentum using the NICE set-up with its associated 648-channel hodoscope spectrometer for γ-ray detection. It is found that the spin-flip and non-spin-flip amplitudes can be parametrized, for small | t |, as exponentials with the same slopes to within a few percent. For | t | ≳ 1 (GeV/ c ) 2 there is a break in the differential cross section. In addition, the A 2 effective trajectory deviates markedly for | t | ≳ 1 GeV/ c ) 2 from the linear behaviour valid for smaller | t |.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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