Hamacher, T.
Charm production
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$D$ Meson Production From 400-{GeV}/$c p p$ Interactions. Evidence for Leading Diquarks?

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bailly, J.L. ; et al.
Phys.Lett.B 201 (1988) 176, 1988.
Inspire Record 252001 DOI 10.17182/hepdata.49611

Results of fitting the differential distributions in x F and p T 2 of D mesons produced in 400 GeV/ c p-p interactions to the form d 2 σ d x F d p T 2 ∝(1−x F ) n exp [−(p T 2 /〈p T 2 〉)] are discussed. The D + distribution is found to be relatively hard [ n =3.1±0.8〈 P t 2 〉=1.32±0.27 (GeV/ c ) 2 ] and the D̄ 0 distribution relatively soft [ n =8.1±1.9,〈 p T 2 〉=0.62±0.14 (GeV/ c ) 2 ] compared to the average for all D's [ n =4.9±0.5,〈 p T 2 〉=0.99±0.10 (GeV/ c ) 2 ]. It is suggested that these distributions could reflect contribution of leading di-quarks in pp collisions. Comparison is made with evidence for leading quarks in charm production in 360 GeV/ cπ − p interactions.

1 data table
Table 1

The invariant (C=INV) and non-invariant (C=NON-INV) distributions are fitted to (1-XL)**POWER. Pt distribution is fitted to EXP(-PT**2/SLOPE).


rivet Analysis
Observation of $e^+ e^- \to D(s$)+- $D^*(s$)-+ at $\sqrt{s}=4$.14-{GeV}

The MARK-III collaboration Blaylock, G. ; Bolton, T. ; Brown, J.S. ; et al.
Phys.Rev.Lett. 58 (1987) 2171, 1987.
Inspire Record 244856 DOI 10.17182/hepdata.20170

We present evidence for the exclusive reaction e+e−→Ds±Ds*∓, observed with the Mark III detector at the SLAC storage ring SPEAR. The Ds± is reconstructed in the φπ± decay mode, while the Ds*∓ is detected as a narrow peak in the recoil-mass distribution. The mass of the Ds* is found to be 2109.3±2.1±3.1 MeV/c2, yielding a Ds*−Ds mass difference of 137.9±2.1±4.3 MeV/c2. The width of the Ds* is <22 MeV/c2 at the 90%-confidence level. The observed signal corresponds to σ(e+e−→Ds+Ds*−+Ds−Ds*+)B(Ds+→φπ+)=30±6±11 pb at s=4.14 GeV.

1 data table
Table 1

No description provided.


$D$ Meson Production From 400 GeV/$c p p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bailly, J.L. ; et al.
Phys.Lett.B 189 (1987) 476, 1987.
Inspire Record 245101 DOI 10.17182/hepdata.12913

We have measured the inclusive production properties of D and D messons produced from pp interactions at s =27.4 GeV . The differential production cross section is well represented by the empirical form d 2 σ d x F d P 2 T = 1 2 [σ ( D / D )(n+1)b](1−|x F |) n exp (−bp 2 T ) with n=4.9 ± 0.5, b=(1.0±0.1)( GeV /c) −2 , and the inclusive D / D cross section σ ( D / D ) is (30.2±3.3) ωb. The QCD fusion model predicts D / D production which is in good agreement with our data except for the magnitude of the cross section which depends sensitively on the assumed mass of the charm quark.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Limit on the Decay D0 $\to e^\pm \mu^\mp$

Riles, Keith ; Dorfan, J. ; Abrams, G.S. ; et al.
Phys.Rev.D 35 (1987) 2914, 1987.
Inspire Record 236093 DOI 10.17182/hepdata.23380

We have searched for the lepton-flavor-violating decay D0→e±μ∓ in 204 pb−1 of e+e− annihilation data at Ec.m.=29 GeV from the Mark II detector. No candidates were found; we estimate an upper limit on the cross section times branching ratio of σ(e+e−→D0,D¯0; inclusive)B(D0→e±μ∓)<0.35 pb at the 90% confidence level. Simple assumptions yield the rough limit B(D0→e±μ∓)<2.1×10−3. AE.

1 data table
Table 1

No description provided.


rivet Analysis
Measurements of Total Hadronic and Inclusive $D^*$ Cross-sections in $e^+ e^-$ Annihilations Between 3.87-{GeV} and 4.5-{GeV}

Osterheld, A. ; Hofstadter, R. ; Horisberger, R. ; et al.
SLAC-PUB-4160, 1986.
Inspire Record 238081 DOI 10.17182/hepdata.18759

None

2 data tables
Table 1

R measurement.

Table 2

D* cross sections.


Observation of Charmed Mesons in Photon-photon Collisions

The JADE collaboration Bartel, W. ; Becker, L. ; Felst, R. ; et al.
Phys.Lett.B 184 (1987) 288-292, 1987.
Inspire Record 235696 DOI 10.17182/hepdata.30214

The inclusive production of D ∗± mesons in single tagged photon-photon collisions is investigated using the JADE detector at PETRA. D ∗± mesons are reconstructed through their decay into D 0 +π ± where the D 0 decays via D 0 →Kππ 0 . The event rate and topology are compared to the expectations of c quark production in the quark-parton model: γγ→c c .

1 data table
Table 1

No description provided.


Inclusive Charm Cross-Sections in 800-GeV/c p p Interactions

The LEBC-MPS collaboration Ammar, R. ; Banerjee, S. ; Baland, J.F. ; et al.
Phys.Lett.B 183 (1987) 110, 1987.
Inspire Record 233423 DOI 10.17182/hepdata.42573

We report a measurement of the inclusive D/D̄ production cross section in 800 GeV/ c proton-proton interactions. The experiment used the high resolution bubble chamber LEBC exposed to an 800 GeV/ c proton beam at the Fermilab MPS. We obtain σ( D/ D ̄ )=59 −15 +22 μ b (statistical errors), having analysed 25% of the total data sample. Comparison with 400 GeV/ c pp dat a obtained with LEBC at CERN shows a D/D̄ cross section increase by a factor of 1.7 −0.5 +0.7 . This is in good agreement with fusion model calculations.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

PAGE FROM PREPRINT.

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Observation of the Decay $B \to$ F X

The CLEO collaboration Haas, P. ; Hempstead, M. ; Jensen, T. ; et al.
Phys.Rev.Lett. 56 (1986) 2781, 1986.
Inspire Record 228879 DOI 10.17182/hepdata.20235

We present evidence for inclusive F-meson production in B-meson decay. The product branching fraction B(B→FX)B(F+→φπ+) is measured to be 0.0038±0.010. The F momentum spectrum indicates the presence of a large component of two-body final states in the decay B→FX.

3 data tables
Table 1

No description provided.

Table 2

DATA SAMPLE CONSISTED OF 77 1/PB. DATA TAKEN ON THE PEAK OF THE UPSI(10575).

Table 3

CONTINUUM DATA SAMPLE CONSISTED OF 36 1/PB. ENERGY JUST BELOW THE UPSI(10575).


Neutral and Charged $D^*$ Production in 360-{GeV}/$c \pi^- p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W. ; Baland, J.F. ; et al.
Phys.Lett.B 169 (1986) 106-112, 1986.
Inspire Record 227059 DOI 10.17182/hepdata.30268

The first data on the production of D ∗ (2010) are presented as observed in π − -proton interactions at √ s = 27 GeV . It is found that D ∗ (2010) dominates the total charm D-meson production, without a significant non-central component.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Direct Measurements of Charmed d Meson Hadronic Branching Fractions

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.
Phys.Rev.Lett. 56 (1986) 2140, 1986.
Inspire Record 220653 DOI 10.17182/hepdata.20248

A new technique is applied to data collected at the ψ(3770) resonance to derive charmed-D-meson branching fractions without relying on the measurement of D-production cross sections. Measurements are presented for three decay modes of the D0 (K−π+, D−π−π+π+, and K−π+π0 and four decay modes of the D+ (K−π+π+,K−π+π+π0,KS0π+, and KS0π+π0). The resulting branching fractions are significantly larger than previous measurements.

2 data tables
Table 1

No description provided.

Table 2

No description provided.