Dear Hiro,
is the mean ZDC vertex itself multiplicity dependent?
It is possible that their is a problem with slewing. I am working
on setting up the ZDC database and putting more slewing corrections
in.
Michael
Quoting Hironori Ito <hito@students.phsx.ukans.edu>:
> Hello. The figure includes any events which ZDC and TPM1 cluster
> vertex exist. (I have to have TPM1 since that is what I am comparing
> with.) There is no additional cuts. Unless the TPM1 cluster vertex
> has
> multiplicity dependence, which I have not heard such a dependence, it is
> coming
> from ZDC vertex. Maybe, the slewing correction is not quite right???
>
> Hiro
>
> On Mon, 19 Mar 2001, Michael Murray wrote:
>
> > Dear Hiro,
> > I guess that the figure was made only
> > for events in which the BB and the TPM1 vertex
> > failed. If so the effect you see could be induced
> > by an (multiplicity dependent)
> > inefficency in the vertex algorithm of
> > these detectors. Could you please remake the
> > same plot for an unbiased sample of events from
> > the same run. Ideally that would be just ZDC triggers.
> > Yours Michael
> >
> > Quoting Hironori Ito <hito@students.phsx.ukans.edu>:
> >
> > > Well. I have another thought about fixing manually. I can not
> > > fix manually since I only use ZDC vertex when I do not have good
> vertex
> > > from BB or TPM1. This means that I can not fix ZDC since I do not
> have
> > > any other reference to fix ZDC Vertex.
> > >
> > > hiro
> > >
> > > On Fri, 16 Mar 2001, Hironori Ito wrote:
> > >
> > > > Hello. I have a question. I remember reading the e-mail about
> > > > ZDC_Vertex do not have Multiplicity dependence. Well, I think it
> is
> > > > there. Look at the figure "ZDC_TPM1_vertex.ps" in
> > > > "http://pii3.brahms.bnl.gov/~hito". The figure is produced from
> > > > run 2336. In this figure, the vertical scale is
> > > > ZDC vertex - TPM1 (cluster) vertex, and the horizontal scale is
> BB
> > > > Mult. Of cause, it is possible that BB Mult is wrong. But, if I
> use
> > > > other mult such as Si and Tile mult, I see the same thing.
> > > Furthermore, I
> > > > do not see this much dependence from BBVertex - TPM1 Vertex
> although
> > > > BBVertex have other problem. Can someone look at this? The fix
> is
> > > > needed since multiplicity in Si can easily is affected by 3-4 cm
> shift
> > > of
> > > > vertex. Until it is fixed, I will manually (in my own code) fix
> > > ZDCVertex
> > > > to align to TPM1 vertex.
> > > >
> > > > Hiro
> > > >
> > > >
> > >
> >
> >
> >
> > Michael Murray, Cyclotron TAMU, 979 845 1411 x 273, Fax 1899
> >
>
Michael Murray, Cyclotron TAMU, 979 845 1411 x 273, Fax 1899
This archive was generated by hypermail 2b29 : Mon Mar 19 2001 - 14:49:10 EST