Baker, R.D.
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Search for narrow structure in proton‐antiproton annihilation cross sections from 1900 to 1960 MeV

Lowenstein, D.I. ; Pealsee, D.C. ; Miller, R.J. ; et al.
Phys.Lett.B 158 (1985) 505-510, 1985.
Inspire Record 221435 DOI 10.17182/hepdata.30389

The p̄p annihilation cross section has been measured with good resolution (∼2 MeV rms) in the mass range 1900–1960 MeV. No narrow structures are seen, the 90% confidence level upper limit being 8–12 mb‐MeV for the integrated area of a resonance in this mass range. However, we do not rule out a very narrow bump‐dip structure seen in an earlier experiment in the 1935–1941 MeV mass interval. The data also do not support the existence of a broad structure previously reported at 1937 MeV.

1 data table
Table 1

Fit of form A + B/D gives A = 8.5 +- 2.5mb and B = 40.7 +- 1.3mb in the mass range 1900 to 1960 MeV.


PRECISE MEASUREMENT OF THE PION CHARGE EXCHANGE FORWARD DIFFERENTIAL CROSS-SECTION AT 522-MEV/C

Gaille, F.C. ; Highland, V.L. ; Auerbach, L.B. ; et al.
Phys.Rev.D 30 (1984) 2408-2410, 1984.
Inspire Record 215121 DOI 10.17182/hepdata.23596

A precise measurement of the differential cross section at zero degrees for the pion charge-exchange reaction π−p→π0n at pπ=522 MeV/c has been made. The result is dσdΩ (0∘)=4.32±0.11 mb/sr.

1 data table
Table 1

DIFFERENTIAL CROSS SECTION AT THETA = 0.


ANGULAR AND ENERGY DEPENDENCE OF THE CROSS-SECTION AND ANALYZING POWER OF THE REACTION P P ----> D PI+ BETWEEN 725-MEV AND 1000-MEV

Mayer, B. ; Bertini, R. ; Cameron, J.M. ; et al.
Nucl.Phys.A 437 (1985) 630-642, 1985.
Inspire Record 217258 DOI 10.17182/hepdata.37040

The differential cross section and analyzing power of the reaction pp → d π + were measured for nine incident proton energies between 725 and 1000 MeV. A magnetic spectrometer was used to detect either deuterons or pions. Cross-section and analyzing-power angular distributions were respectively fitted with Legendre polynomial and associated Legendre function expansions, the coefficients of which were found to vary smoothly with energy in the vicinity of the alleged 3 F 3 dibaryon resonance.

12 data tables
Table 1

Data present here in form of Legendre polynomial fit.

Table 2

Legendre Polynomial fit to cross section.

Table 3

Legendre polynomial fit to analysing power.

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CHARM PRODUCTION IN NEUTRON NUCLEON INTERACTIONS

Tzeng, L. ; Mcbride, P.L. ; Cooper, P.S. ; et al.
Phys.Rev.Lett. 55 (1985) 1172-1175, 1985.
Inspire Record 221439 DOI 10.17182/hepdata.20303

Hadronic production of charmed particles in association with muons from their semileptonic decay has been observed in a high-resolution streamer-chamber experiment performed at Fermilab. A miss-distance analysis of the pictures gives a signal of 17.3±4.7 events. Depending on the production model this corresponds to a range of neutron-nucleon cross sections from 8 to 50 μb, assuming an A23 dependence.

2 data tables
Table 1

NEUTRON BEAM : 280 GEV - AVERAGE ENERGY, PEAKED AT 320 GEV WITH FWHW OF 130 GEV.

Table 2

NEUTRON BEAM : 280 GEV - AVERAGE ENERGY, PEAKED AT 320 GEV WITH FWHW OF 130 GEV.


DIFFERENCES BETWEEN PROTON AND PI- INDUCED PRODUCTION OF THE CHARMONIUM CHI STATES

Bauer, Daniel A. ; Graff, T.L. ; Lukens, P.T. ; et al.
Phys.Rev.Lett. 54 (1985) 753-756, 1985.
Inspire Record 216287 DOI 10.17182/hepdata.20333

The charmonium χ states are observed in both π− and p Be interactions near 200 GeV/c via their radiative decay into J/ψ. The χ(3510) and χ(3555) are produced with roughly equal cross sections in π− collisions while the χ(3555) dominates in p collisions. Simple gluon fusion can account for χ production with incident protons but additional mechanisms are needed for incident π−.

1 data table
Table 1

No description provided.


Measurement of $e^+ e^- \to \mu^+ \mu^-$: A Test of Electroweak Theories

The Mark-J collaboration Adeva, B. ; Becker, U. ; Becker-Szendy, R. ; et al.
Phys.Rev.Lett. 55 (1985) 665, 1985.
Inspire Record 214607 DOI 10.17182/hepdata.3237

We use the reaction e+e−→μ+μ−, in the Mark J detector at the DESY high-energy e+e− collider PETRA, to test the standard electroweak theory and find good agreement. We also set limits on the parameters of several extended gauge theories.

6 data tables
Table 1

CROSS SECTION MEASUREMENT RELATIVE TO PREDICTED QED CROSS SECTION.

Table 2

FORWARD-BACKWARD ASYMMETRY. THE SYSTEMATIC ERROR IN THE ASYMMETRY IS <0.5 PCT.

Table 3

ANGULAR DISTRIBUTIONS NOT GIVEN IN PAPER. SUPPLIED BY E.DEFFUR.

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Real to Imaginary Ratio of the $\bar{p} p$ Forward Elastic Scattering Amplitude in the Momentum Range Between 180-{MeV}/$c$ and 590-{MeV}/$c$

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 158 (1985) 180-185, 1985.
Inspire Record 213992 DOI 10.17182/hepdata.30392

The real-to-imaginary ratio of the p p forward elastic scattering amplitude has been measured at the LEAR facility of CERN by the Coulomb-nuclear interference method at seven beam momenta between 181 and 590 MeV/ c . The ratio is positive at 590 MeV/ c , becomes negative below 500 MeV/ c , reaches a minimum at 260 MeV/ c and then crosses zero again at about 230 MeV/ c .

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


First Observation and Cross-section Measurement of $\nu_e e^- \to \nu_e e^-$

Allen, R.C. ; Bharadwaj, V. ; Brooks, G.A. ; et al.
Phys.Rev.Lett. 55 (1985) 2401, 1986.
Inspire Record 215874 DOI 10.17182/hepdata.20326

We report the first observation and cross-section measurement of νe+e−→νe+e−. Using neutrinos of energy less than 53 MeV, we observed 63±17 events consistent with ν+e−→ν+e−, of which 51±17 events are assigned to νe+e−→νe+e−. The resulting cross section, {[8.9±3.2(statistical) ±1.5(systematic)]×10−45 cm2/MeV} Eν, agrees with standard electroweak theory, rules out constructive interference between weak charged-current and neutral-current interactions, and begins to indicate the existence of interference between these two interactions.

1 data table
Table 1

No description provided.


Anti-proton - Proton Elastic Cross-sections in the Momentum Range Between 180-{MeV}/$c$ and 600-{MeV}/$c$

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 166 (1986) 113-118, 1986.
Inspire Record 217928 DOI 10.17182/hepdata.30308

Differential cross sections for p̄p elastic scattering have been measured in the full angular range for the p̄ momenta between 180 and 600 MeV/ c . It is found that s- and p-wave scattering is dominant below 300 MeV/ c . The s-wave component in the total cross section is 40–60% below 300 MeV/ c , in contrast to the NN scattering where it is about 90%. The s-, p- and d-wave scattering amplitudes are derived.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurement of the $\bar{p} p \to \bar{n} n$ Cross-section at Low $\bar{p}$ Momenta

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 169 (1986) 302-308, 1986.
Inspire Record 219986 DOI 10.17182/hepdata.30264

First measurements of the differential cross section are presented for p ̄ p → n ̄ n at LEAR in the momentum range between 180 and 600 MeV/ c . The differential cross sections show a forward peaking followed by a smooth drop-off. No indication of the “bump-dip” structure reported at higher momenta has been observed. The angle-integrated charge-exchange cross sections are determined down to E n ̄ n cm = 6.6 MeV .

2 data tables
Table 1

No description provided.

Table 2

No description provided.