HEPData Search

Showing 7 of 7 results

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

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

Phys.Lett.B 83 (1979) 131, 1979.

Inspire Record 141023 DOI 10.17182/hepdata.49657

Measurements were made of the cross section of the reactions π − p → ν ′(958)n, η ′ → 2 γ at momenta at 15, 20, 25, 30 and 40 GeV/c. The experiment was carried out on the IHEP 70 GeV accelerator using the 648 channel hodoscope spectrometer NICE for γ-ray detection. A total of 6000 η′ mesons were recorded. A sharp drop is seen in the differential cross section for t → 0. The dependences of the differential cross sections for the π − p → η ′n and π − p → η n on t are identical. On the basis of the ratio of the cross sections for these reactions at t = 0, i.e. R( η′ n ) t=0 = 0.55 ± 0.06 , the singlet-octet mixing angle for pseudoscalar mesons was determined to be β = −(18.2 ± 1.4)°.

8 data tables

Table 1

Table 2

AVERAGE RATIO IS 2.76 +- 0.07 PCT.

Table 3

AVERAGE RATIO IS 0.52 +- 0.02.

More…

Study of narrow mesons near their thresholds

Binnie, D.M. ; Camilleri, L. ; Debenham, N.C. ; et al.

Phys.Rev.D 8 (1973) 2789-2813, 1973.

Inspire Record 93328 DOI 10.17182/hepdata.47579

A novel form of mass spectrometer has been used to measure the masses, widths, and cross sections of the η, ω, X0(958), and φ mesons near their respective thresholds in the reaction π−+p→missingmass+n. The incident momentum is varied in small steps through the threshold while neutrons of a given momentum are detected near zero degrees. The lower limit of the c.m. momentum P* at which measurements have been made ranges from about 50 MeV/c at the φ to about 30 MeV/c at the η. A somewhat low value for the ω mass, 782.3 ± 0.6 MeV, is found. The width of the X0 is < 1.9 MeV (95% confidence level). All four mesons show evidence of S-wave production, with values of σP* of 21.2 ± 1.8, 0.35 ± 0.03, and 0.29 ± 0.06 μb/(MeV/c) for the η, X0, and φ, respectively. A rapid rise in the ω cross section appears to be modified by a final-state interaction. The effect of this rise can probably be seen in some S11 pion-nucleon phase-shift solutions. Evidence is also presented of a sudden drop in the π+π− mass spectrum just above the threshold for the production of a K+K− pair. The paper includes a comprehensive discussion of the method and of the details of the spectrometer.

1 data table

Table 1

CROSS SECTIONS NEAR THRESHOLD.

Study of the Charge Exchange Reactions $\pi^- p \to (\pi^0$, $\eta$, $\eta^\prime$) $n$ at 63-{GeV}

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.

Z.Phys.C 8 (1981) 95, 1981.

Inspire Record 156266 DOI 10.17182/hepdata.49658

None

4 data tables

Table 1

INCLUDING SYSTEMATIC ERRORS.

Table 2

STATISTICAL ERRORS ONLY.

Table 3

STATISTICAL ERRORS ONLY.

More…

Search for neutral mesons near 1 gev/c-squared

Binnie, D.M. ; Camilleri, L. ; Carr, J. ; et al.

Phys.Rev.Lett. 32 (1974) 392-395, 1974.

Inspire Record 94572 DOI 10.17182/hepdata.21308

In a study of the missing-mass spectrum near 1 GeV in the reaction π−+p→MM+n at three incident momenta near 2 GeV, we find no evidence for the recently reported narrow neutral mesons at 940, 963, and 1033 MeV.

1 data table

Table 1

No description provided.

Results on the production cross-sections pi- p ---> neutrals and pi- p ---> chi0(2gamma) n at 3.8, 6, 8 and 12 gev/c

Apel, W.D. ; Auslaender, J. ; Mueller, H. ; et al.

Phys.Lett.B 46 (1973) 459-464, 1973.

Inspire Record 95163 DOI 10.17182/hepdata.28058

The ratio between the cross sections for the reactions π − p→ χ ↳ 2γ 0 n and π − p → η →2 γ n has been measured to be (2.4 ± 0.9) × 10 −2 , (2.1 ± 0.6) × 10 −2 and (2.8 ± 1.3) × 10 −2 at 3.8,6,8 and 12 GeV/ c incident momentum respectively.

1 data table

Table 1

ETAPRIME CROSS SECTIONS DEDUCED FROM THEIR RATIO TO ETA PRODUCTION, USING THE RESULTS OF O. GUISAN ET AL., PL 18, 200 (1965).