Hi,
I post the link where the fit results related to this study
can be found: http://www.slac.stanford.edu/~menges/Vub/scra/intpur
What we learn already from these results is that the result is stable
above say a Integrated Purity cut of 0.4-0.5 and that the statistical
error on BRBR would of order 12% which is good.
Heiko
On Tue, 5 Sep 2006, Wolfgang Menges wrote:
> Hi all,
>
> here are a few numbers from my study of an integrated purity cut. I
> have the following cuts: 0.0, 0.1, 0.2 0.3, 0.4, 0.5, 0.6, 0.7, 0.8. The
> numbers are from VVFs result.dat file.
>
> Number of semileptonic events before background subtraction. To get an
> impression of what we loose:
>
> Nsl = 105686
> Nsl = 105686
> Nsl = 105686
> Nsl = 90040.9
> Nsl = 70120.1
> Nsl = 59346.9
> Nsl = 43481.7
> Nsl = 29999.7
> Nsl = 14712.2
>
> Background subtracted ratio (looks quite stable):
>
> (Nsl - BG)/Nsl (vub corrected) = 0.929849
> (Nsl - BG)/Nsl (vub corrected) = 0.929849
> (Nsl - BG)/Nsl (vub corrected) = 0.929849
> (Nsl - BG)/Nsl (vub corrected) = 0.929883
> (Nsl - BG)/Nsl (vub corrected) = 0.929295
> (Nsl - BG)/Nsl (vub corrected) = 0.929081
> (Nsl - BG)/Nsl (vub corrected) = 0.928474
> (Nsl - BG)/Nsl (vub corrected) = 0.928204
> (Nsl - BG)/Nsl (vub corrected) = 0.927771
>
> The pstarfactor:
>
> pstarfact 1.05571 +- 0.0161501
> pstarfact 1.05571 +- 0.0161501
> pstarfact 1.05571 +- 0.0161501
> pstarfact 1.04933 +- 0.0171875
> pstarfact 1.04953 +- 0.0194575
> pstarfact 1.04083 +- 0.0207942
> pstarfact 1.03212 +- 0.0231472
> pstarfact 1.01948 +- 0.0269841
> pstarfact 1.00562 +- 0.0377533
>
> And finally the partial BRBR:
>
> PartialBRBR = 0.0139225 +- 0.00116947(stat) +- 0.000404075(MC stat)
> PartialBRBR = 0.0139225 +- 0.00116947(stat) +- 0.000404075(MC stat)
> PartialBRBR = 0.0139225 +- 0.00116947(stat) +- 0.000404075(MC stat)
> PartialBRBR = 0.0126852 +- 0.00123447(stat) +- 0.000405462(MC stat)
> PartialBRBR = 0.0119573 +- 0.00133944(stat) +- 0.000484691(MC stat)
> PartialBRBR = 0.0110474 +- 0.00137170(stat) +- 0.000501760(MC stat)
> PartialBRBR = 0.0112305 +- 0.00147592(stat) +- 0.000553075(MC stat)
> PartialBRBR = 0.0100832 +- 0.00184243(stat) +- 0.000674057(MC stat)
> PartialBRBR = 0.0121519 +- 0.00238772(stat) +- 0.000883651(MC stat)
>
> I would drop the last number and then the trend is lower partial BRBR
> for purer samples. Both error sources increase with purer sample as
> expected. So, what is the final figure of merit to choose a cut? Needs
> to be discussed today.
>
> Cheers,
>
> Wolfgang
> --
> ------------------------------------------------------------------------
> Wolfgang Menges
> Queen Mary, University of London SLAC, MS 35
> Mile End Road 2575 Sand Hill Road
> London, E1 4NS, UK Menlo Park, CA 94025, USA
> +44 20 7882 3753 ++1 650 926 8503
> [log in to unmask]
> ------------------------------------------------------------------------
>
|