rivet is hosted by Hepforge, IPPP Durham

Rivet analyses reference

CUSB_1991_I325661

Inclusive $B^*$ cross-section above the $\Upsilon(4S)$
Experiment: CUSB (CESR)
Inspire ID: 325661
Status: VALIDATED
Authors:
  • Peter Richardson
References:
  • Phys.Rev.Lett. 67 (1991) 1692-1695
Beams: e- e+
Beam energies: (5.3, 5.3); (5.3, 5.3) GeV
Run details:
  • e+e- collisions

Measurement of the inclusive cross section for $B^*$ production at energies above the $\Upsilon(4S)$ mass.

Source code: CUSB_1991_I325661.cc
 1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/UnstableParticles.hh"
 4
 5namespace Rivet {
 6
 7
 8  /// @brief Add a short analysis description here
 9  class CUSB_1991_I325661 : public Analysis {
10  public:
11
12    /// Constructor
13    RIVET_DEFAULT_ANALYSIS_CTOR(CUSB_1991_I325661);
14
15
16    /// @name Analysis methods
17    //@{
18
19    /// Book histograms and initialise projections before the run
20    void init() {
21
22      // Initialise and register projections
23      declare(UnstableParticles(), "UFS");
24
25      // Book histograms
26      book(_c_Bstar, "/TMP/sigma_Bstar");
27    }
28
29
30    /// Perform the per-event analysis
31    void analyze(const Event& event) {
32      const FinalState& ufs = apply<FinalState>(event, "UFS");
33      unsigned int nBstar(0);
34      // Get Bottom hadrons
35      const Particles bhads = ufs.particles(Cuts::abspid==513 or Cuts::abspid==523);
36      // find the Bstars
37      for (const Particle& p : bhads) {
38        if(abs(p.pid())==513 || abs(p.pid())==523) {
39          if(!p.hasDescendantWith(Cuts::pid == p.pid())) ++nBstar;
40        }
41      }
42      if(nBstar!=0)
43        _c_Bstar->fill(nBstar);
44    }
45
46
47    /// Normalise histograms etc., after the run
48    void finalize() {
49      double fact = crossSection()/ sumOfWeights() /nanobarn;
50      double sig = _c_Bstar->val()*fact;
51      double err = _c_Bstar->err()*fact;
52      Scatter2D    temphisto(refData(1, 1, 1));
53      Scatter2DPtr mult;
54      book(mult, 1, 1, 1);
55      for (size_t b = 0; b < temphisto.numPoints(); b++) {
56	const double x  = temphisto.point(b).x();
57	pair<double,double> ex = temphisto.point(b).xErrs();
58	pair<double,double> ex2 = ex;
59	if(ex2.first ==0.) ex2. first=0.0001;
60	if(ex2.second==0.) ex2.second=0.0001;
61	if (inRange(sqrtS()/GeV, x-ex2.first, x+ex2.second)) {
62	  mult->addPoint(x, sig, ex, make_pair(err,err));
63	}
64	else {
65	  mult->addPoint(x, 0., ex, make_pair(0.,.0));
66	}
67      }
68    }
69
70    //@}
71
72
73    /// @name Histograms
74    //@{
75    CounterPtr _c_Bstar;
76    //@}
77
78
79  };
80
81
82  // The hook for the plugin system
83  RIVET_DECLARE_PLUGIN(CUSB_1991_I325661);
84
85
86}