Bc relative cross section

B_c → J/ψ+μ+ν cross section with 1 fb^-1 data

This web page summarizes the results of the ratio of the production cross section times branching fraction of B_c^± → J/ψ+&mu^±+ν
relative to B^± → J/ψ+K^± for two p_T(B) cuts. The measurement is done with in 1 fb^-1 of exclusive J/ψ data.

The results have been approved by B Group Meeting as of March 5, 2009.

We measure

at p_T(B) > 4 GeV/c and and at p_T(B) > 6 GeV/c cuts as:

A more detailed summary of the results can be found: here

CDF Run I (with L=110 pb^-1) and Run II (with L=360 pb^-1) results of the ratio of the production cross section times
branching fraction of B_c^± → J/ψ+l^±+ν relative to B^± → J/ψ+K^± are:

Run I result was published in Phys.Rev.D58,112004(1998): here
Run II B_c → J/ψ+μ+ν decay channel measurement (L=360 pb^-1) public web page is here
Run II B_c → J/ψ+e+ν decay channel measurement (L=360 pb^-1) public web page is here

B_c invariant mass distribution using the J/ψ+μ decays channel.

Below are the eps and jpeg versions of figures meant for download.

Figure 1: J/ψ mass (.eps)(.jpg)
Figure 2: J/ψ+μ mass from B_c decays with backgrounds superimposed (.eps)(.jpg)
Figure 3: J/ψ+K^± mass from B^± decays (.eps)(.jpg)
Figure 4: J/ψ+μ mass from B_c decays with backgrounds subtraction applied (black) and B_c Monte Carlo (red) (.eps)(.jpg)
Figure 5: p_T of J/ψ+μ from B_c decays with backgrounds subtraction applied (black) and B_c Monte Carlo (red) (.eps)(.jpg)
Figure 6: p_T of J/ψ+K^± from B^± decays in data (black) and in Monte Carlo (red) (.eps)(.jpg)
Figure 7: acceptance for B^± → J/ψ+K^± decays vs p_T(B^±) (.eps)(.jpg)
Table 1: B_c excess and backgrounds for B_c → J/ψ+μ+ν decay channel is here
Table 2: B_c background systematic uncertainty: here
Table 3: B_c to B^± relative efficiency systematic uncertainty: here
Table 4: B_c to B^± relative cross section results: here