Cassel, D.G.
Upsilon
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Suppression of Upsilon Production in d+Au and Au+Au Collisions at sqrt(s_NN) = 200 GeV

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Lett.B 735 (2014) 127-137, 2014.
Inspire Record 1269346 DOI 10.17182/hepdata.102940

We report measurements of Upsilon meson production in p+p, d+Au, and Au+Au collisions using the STAR detector at RHIC. We compare the Upsilon yield to the measured cross section in p+p collisions in order to quantify any modifications of the yield in cold nuclear matter using d+Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p+p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon(1S+2S+3S) in the rapidity range |y|<1 in d+Au collisions of R_dAu = 0.79 +/- 0.24 (stat.) +/- 0.03 (sys.) +/- 0.10 (pp sys.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au+Au collisions, we measure a nuclear modification factor of R_AA=0.49 +/- 0.1 (stat.) +/- 0.02 (sys.) +/- 0.06 (pp sys.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au+Au collisions. The additional suppression in Au+Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined Quark-Gluon Plasma. However, understanding the suppression seen in d+Au is still needed before any definitive statements about the nature of the suppression in Au+Au can be made.

14 data tables
Table 1

Invariant mass distributions of electron pairs in the region $|y_{ee}| < 0.5$, p+p.

Table 2

Invariant mass distributions of electron pairs in the region $|y_{ee}| < 0.5$, d+Au.

Table 3

(a) $B_{ee} \times d\sigma/dy$ vs. $y$ for p+p collisions and for d+Au collisions (scaled down by 103).

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rivet Analysis
Antideuteron production in $\Upsilon(nS)$ decays and in $e^+e^- \to q\overline{q}$ at $\sqrt{s} \approx 10.58 \mathrm{\,Ge\kern -0.1em V}$

The BaBar collaboration Lees, J.P. ; Poireau, V. ; Tisserand, V. ; et al.
Phys.Rev.D 89 (2014) 111102, 2014.
Inspire Record 1286317 DOI 10.17182/hepdata.64605

We present measurements of the inclusive production of antideuterons in $e^+e^-$ annihilation into hadrons at $\approx 10.58 \mathrm{\,Ge\kern -0.1em V}$ center-of-mass energy and in $\Upsilon(1S,2S,3S)$ decays. The results are obtained using data collected by the BABAR detector at the PEP-II electron-positron collider. Assuming a fireball spectral shape for the emitted antideuteron momentum, we find $\mathcal{B}(\Upsilon(1S) \to \bar{d}X) = (2.81 \pm 0.49 \mathrm{(stat)} {}^{+0.20}_{-0.24} \mathrm{(syst)})/! \times /! 10^{-5}$, $\mathcal{B}(\Upsilon(2S) \to \bar{d}X) = (2.64 \pm 0.11 \mathrm{(stat)} {}^{+0.26}_{-0.21} \mathrm{(syst)})/! \times /! 10^{-5}$, $\mathcal{B}(\Upsilon(3S) \to \bar{d}X) = (2.33 \pm 0.15 \mathrm{(stat)} {}^{+0.31}_{-0.28} \mathrm{(syst)})/! \times /! 10^{-5}$, and $\sigma (e^+e^- \to \bar{d}X) = (9.63 \pm 0.41 \mathrm{(stat)} {}^{+1.17}_{-1.01} \mathrm{(syst)}) \mbox{\,fb}$.

5 data tables
Table 1

The rate of antideuteron production from the decay of UPSILON(3S).

Table 2

The rate of antideuteron production from the decay of UPSILON(2S).

Table 3

The rate of antideuteron production from the decay of UPSILON(1S).

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rivet Analysis
Upsilon dipion transitions at energies near the Upsilon(4S).

The CLEO collaboration Glenn, S. ; Kwon, Y. ; Lyon, Adam L. ; et al.
Phys.Rev.D 59 (1999) 052003, 1999.
Inspire Record 474676 DOI 10.17182/hepdata.47202

Using a data sample collected with the CLEO II detector at CESR, we have searched for dipion transitions between pairs of $\Upsilon$ resonances at energies near the $\Upsilon(4S)$. We obtain upper limits $B(\Upsilon(4S)\to \Upsilon(2S)\pi^+\pi^-) < 3.9 \times 10^{-4}$ and $B(\Upsilon(4S)\to \Upsilon(1S)\pi^+\pi^-) < 1.2 \times 10^{-4}$. We also observe the transitions $\Upsilon(3S)\to \Upsilon(1S)$, $\Upsilon(3S)\to \Upsilon(2S)$, and $\Upsilon(2S)\to \Upsilon(1S)$, from which we measure the cross-sections for the radiative processes $e^+e^- \to \Upsilon(3S)\gamma$ and $e^+e^- \to \Upsilon(2S)\gamma$.

1 data table
Table 1

The cross sections are averaged from the ones obtained for E+ E- --> GAMMA UPSI(nS) < PI+ PI- UPSI(mS) < MU+ MU- > > and E+ E- --> GAMMA UPSI(nS) < PI+ PI-UPSI(mS) < E+ E- > > channels with n=2,3, m=1,2.


Measurement of elastic Upsilon photoproduction at HERA.

The ZEUS collaboration Breitweg, J. ; Derrick, M. ; Krakauer, D. ; et al.
Phys.Lett.B 437 (1998) 432-444, 1998.
Inspire Record 473522 DOI 10.17182/hepdata.44207

The photoproduction reaction gamma p -> mu+ mu- p has been studied in ep interactions using the ZEUS detector at HERA. The data sample corresponds to an integrated luminosity of 43.2 pb^{-1}. The Upsilon meson has been observed in photoproduction for the first time. The sum of the products of the elastic Upsilon(1S), Upsilon(2S), Upsilon(3S) photoproduction cross sections with their respective branching ratios is determined to be 13.3 +- 6.0(stat.)^{+2.7}_{-2.3}(syst.) pb at a mean photon-proton centre of mass energy of 120 GeV. The cross section is above the prediction of a perturbative QCD model.

2 data tables
Table 1

Unresolved UPSILON cross sections (times branching ratio to two muons).

Table 2

Mean photoproduction cross section for UPSI(1S) production.


$\Sigma(c$)++ 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.


Study of gluon versus quark fragmentation in Upsilon --> g g gamma and e+ e- --> q anti-q gamma events at s**(1/2) = 10-GeV.

The CLEO collaboration Alam, M.S. ; Athar, S.B. ; Ling, Z. ; et al.
Phys.Rev.D 56 (1997) 17-22, 1997.
Inspire Record 439530 DOI 10.17182/hepdata.47233

Using data collected with the CLEO II detector at the Cornell Electron Storage Ring, we determine the ratio R(chrg) for the mean charged multiplicity observed in Upsilon(1S)->gggamma events, to the mean charged multiplicity observed in e+e- -> qqbar gamma events. We find R(chrg)=1.04+/-0.02+/-0.05 for jet-jet masses less than 7 GeV.

1 data table
Table 1

No description provided.


Measurement of the direct photon spectrum in Upsilon(1S) decays.

The CLEO collaboration Nemati, B. ; Richichi, S.J. ; Ross, W.R. ; et al.
Phys.Rev.D 55 (1997) 5273-5281, 1997.
Inspire Record 425927 DOI 10.17182/hepdata.52340

Using data taken with the CLEO II detector at the Cornell Electron Storage Ring, we have determined the ratio of branching fractions: $R_{\gamma} \equiv \Gamma(\Upsilon(1S) \rightarrow \gamma gg)/\Gamma(\Upsilon(1S) \rightarrow ggg) = (2.75 \pm 0.04(stat.) \pm 0.15(syst.))%$. From this ratio, we have determined the QCD scale parameter $\Lambda_{\overline{MS}}$ (defined in the modified minimal subtraction scheme) to be $\Lambda_{\overline{MS}}= 233 \pm 11 \pm 59$ MeV, from which we determine a value for the strong coupling constant $\alpha_{s}(M_{\Upsilon(1S)}) = 0.163 \pm 0.002 \pm 0.014$, or $\alpha_{s}(M_{Z}) = 0.110 \pm 0.001 \pm 0.007$.

1 data table
Table 1

The ALPHAS at MZ is extrapolation from M(UPSI).


rivet Analysis
Measurement of the inclusive B* cross-section above the Upsilon (4S)

The CLEO-II collaboration Akerib, D.S. ; Barish, B. ; Cowen, D.F. ; et al.
Phys.Rev.Lett. 67 (1991) 1692-1695, 1991.
Inspire Record 29927 DOI 10.17182/hepdata.19887

Using the CLEO II detector at the Cornell Electron Storage Ring, we have determined the inclusive B* cross section above the Υ(4S) resonance in the energy range from 10.61 to 10.70 GeV. We also report a new measurement of the energy of the B*→Bγ transition photon of 46.2±0.3±0.8 MeV.

2 data tables
Table 1

Hadronic cross section above the continuum. The final state is an unknown mixture of B BBAR + B* BBAR + B B*BAR (+ B* B*BAR only at the highest energy).

Table 2

Inclusive B* cross section.


rivet Analysis
A Measurement of the Direct Photon Spectrum From the $\Upsilon$ (1s)

The CLEO collaboration Csorna, S.E. ; Mestayer, M.D. ; Panvini, R.S. ; et al.
Phys.Rev.Lett. 56 (1986) 1222, 1986.
Inspire Record 220652 DOI 10.17182/hepdata.20260

We have observed decays of the ϒ(1S) into hadronic final states containing high-energy photons. These are interpreted as coming from the decay ϒ(1S)→γ+gluon+gluon. We compare the shape of the observed photon energy spectrum with several theoretical predictions and deduce the value of the strong-coupling constant αs and the QCD scale parameter ΛMS― (MS― denotes the modified minimal-subtraction scheme) associated with each prediction.

2 data tables
Table 1

DATA TAKEN ON THE PEAK OF THE UPSI(9460).

Table 2

DATA TAKEN ON THE PEAK OF THE UPSI(9460).


rivet Analysis
A Measurement of the Branching Fraction of the Decay $\Upsilon$ (1s) $\to \tau^+ \tau^-$

The CLEO collaboration Giles, R. ; Hassard, J. ; Hempstead, M. ; et al.
Phys.Rev.Lett. 50 (1983) 877, 1983.
Inspire Record 188803 DOI 10.17182/hepdata.20525

The branching fraction for the decay of the ϒ(1S) into τ paris has been measured to be (3.4±0.4±0.4)%. This result agrees with the previously measured branching ratio of the decay into muon pairs.

2 data tables
Table 1

VISIBLE CROSS SECTIONS IN THE PEAK.

Table 2

No description provided.