Conversi, M.
Max results
Sort by Reverse order

Showing 10 of 6477 results

Date

D*+- Production by e+ e- Annihilation Near 34.4-GeV Center-Of-Mass Energy

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 126 (1983) 493-498, 1983.
Inspire Record 196842 DOI 10.17182/hepdata.30721

D ∗± production via e + e − →D ∗± X has been measured at an average CM energy of 34.4 GeV. The D ∗± energy spectrum is hard, with a maximum near χ = 0.6. The size of the D ∗ cross section, R D ∗ = σ( e + e − → D ∗ X ) σ μμ = 2.50 ± 0.64 ± 0.88 (assuming R D ∗0 = R D ∗+ ) indicates that a large fraction of charm quark production yields D ∗ mesons. The D ∗± angular distribution exhibits a forward—backward asymmetry, A = −0.28 ± 0.13. This is consistent with that expected in the standard theory for weak neutral currents and leads to | g A c | = 0.89 ± 0.44 for the axial vector coupling of the charm quark.

3 data tables
Table 1

ASSUMES EQUAL RATES FOR CHARGED AND NEUTRAL D*'S. ONLY CHARGED ARE DETECTED.

Table 2

DATA PEAKS AT X=0.6 TO 0.8.

Table 3

ASYMMETRY MEASUREMENT. THETA IS THE ANGLE BETWEEN THE E- AND THE D*.


The Ratio of the Nucleon Structure Functions f2 (n) for Iron and Deuterium

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 123 (1983) 275-278, 1983.
Inspire Record 188925 DOI 10.17182/hepdata.30745

Using the data on deep inelastic muon scattering on iron and deuterium the ratio of the nucleon structure functions F 2 N ( Fe )/ F 2 N ( D ) is presented. The observed x -dependence of this ratio is in disagreement with existing theoretical predictions.

1 data table
Table 1

RANGE OF Q*2 VARIES WITH X. E.G. AT X=0.05 , 9<Q2<27. AT X=0.65 , 36<Q2<170 GEV**2.


Observation of a Narrow State at 2.46-GeV/c**2: A Candidate for the Charmed Strange Baryon a+

Biagi, S.F. ; Bourquin, M. ; Britten, A.J. ; et al.
Phys.Lett.B 122 (1983) 455, 1983.
Inspire Record 188802 DOI 10.17182/hepdata.30747

A narrow state has been observed in the reaction Σ − + Be → ( Λ K − π + π + ) + X in an experiment at the CERN SPS hyperon beam. At 2.46 GeV/ c 2 the effective ( Λ K − π + π + ) mass distribution shows an excess of 82 events above a background estimated to be 147, corresponding to a statistical significance of more than 6 standard deviations. The positive charge of the observed final state, which has strangeness −2, suggests the interpretation as a Cabibbo favoured decay of the charmed strange baryon, A + [quark content (csu)]. The cross section times branching ratio is measured to be σ · B = (5.3 ± 2.0) μ b/ (Be nucleus) for x > 0.6. The invariant production cross section is described by E d 3 σ /d p 3 ∞ (1 - x ) (1.7±0.7) exp[−(1.1 −0.4 +0.7 ) p T 2 ].

1 data table
Table 1

No description provided.


Observation of Jets in High Transverse Energy Events at the CERN Proton - anti-Proton Collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 123 (1983) 115-122, 1983.
Inspire Record 188735 DOI 10.17182/hepdata.30754

With a segmented total absorption calorimeter of large acceptance, we have measured the total transverse energy spectrum for pp̄ collisions at s 1 2 = 540 GeV up to ΣE T = 130 GeV in the pseudo-rapidity range | η |< 1.5. Using two different algorithms, we have looked for localized depositions of transverse energy (jets). For ΣE T > 40 GeV , the fraction of events with two jets increases with Σ E T ; this event structure is dominant for ΣE T > 100 GeV. We measure the inclusive jet cross section up to E T (jet) = 60 GeV and the two-jets mass distribution to 120 GeV/ c 2 . The measured cross sections are compatible with the predictions of hard scattering models based on QCD.

2 data tables
Table 1

DATA TAKEN IN 1981 WITH GLOBAL TRANSVERSE ENERGY TRIGGER.

Table 2

DATA TAKEN IN 1982 WITH LOCAL TRANSVERSE ENERGY TRIGGER.


Inclusive Charged Particle Production at the CERN anti-p p Collider

The UA2 collaboration Banner, M. ; Bloch, P. ; Bonaudi, F. ; et al.
Phys.Lett.B 122 (1983) 322-328, 1983.
Inspire Record 190969 DOI 10.17182/hepdata.30782

Transverse momentum distributions of pions, kaons and protons have been measured around 90° in the UA2 detector at the SPS p p collider, at a CM energy of 540 GeV. All the cross sections have increased by more than a factor of 2 over those measured at ISR energies and exhibit a flatter behaviour with respect to transverse momentum.

1 data table
Table 1

No description provided.


MEASUREMENT OF THE DEUTERON STRUCTURE FUNCTION F2 AND A COMPARISON OF PROTON AND NEUTRON STRUCTURE

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 123 (1983) 123-126, 1983.
Inspire Record 188737 DOI 10.17182/hepdata.30753

The deuteron structure function F 2 d has been measured in 280 GeV μ + d interactions. Existing measurements of F 2 p , made with the same apparatus, are used to calculate F 2 p − F 2 n and F 2 n F 2 p . The ratio F 2 n F 2 p has a similar x dependence to that of earlier measurements at lower Q 2 .

10 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

DIFFRACTIVE K0 LAMBDA0 PRODUCTION BY NEUTRONS WITH 40-GeV/c MEAN MOMENTUM

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
PHE 83-1, 1983.
Inspire Record 190017 DOI 10.17182/hepdata.31222

None

1 data table
Table 1

No description provided.


DIFFRACTIVE PRODUCTION OF A NARROW BARYON IN NEUTRON CARBON INTERACTIONS

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Dubna Jinr - 83-602 (83,REC.NOV.) 6p, 1983.
Inspire Record 196394 DOI 10.17182/hepdata.39600

None

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

THREE PION PRODUCTION ON NUCLEI AT 200-GEV

Zielinski, M. ; Berg, D. ; Chandlee, C. ; et al.
Z.Phys.C 16 (1983) 197-204, 1983.
Inspire Record 190869 DOI 10.17182/hepdata.16390

We have carried out a systematic study of the coherent dissociation of pions into 3 pions using nuclear targets. The experiment was performed at Fermilab using a high resolution forward spectrometer. Data were taken with carbon, copper and lead targets at an incident momentum of 202.5 GeV/c. Results are presented on momentum transfers, 3-pion masses, and on the nuclearA-dependence of the production cross section.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Inclusive $\Delta^{++}$ and $\Lambda$ Production in Proton Proton Interactions at {ISR} Energies

Drijard, D. ; Fabbri, F. ; Fischer, H.G. ; et al.
Z.Phys.C 21 (1984) 321, 1984.
Inspire Record 188801 DOI 10.17182/hepdata.16280

Inclusive cross sections forΔ++ production inpp interactions at different ISR energies are presented. The differential cross sectiondσ/dx forΔ++ production is found to be approximately independent of Feynmanx. No strong energy dependence is seen over the ISR energy range. The topological cross sections ofΔ++ at\(\sqrt s= 62\) GeV show an appreciable contribution from non-diffractive production mechanisms. An upper limit for theΔ0 production cross section is determined.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.