From: Bolton, Tim (bolton@phys.ksu.edu)
Date: Wed Sep 21 2005 - 08:53:47 CDT
Being a two-fingered typist, I'm fond of the combo construct
/generator/gun particleName x y z px py pz KE polz poly polz
where the character strings seem to be accepted OK as in
/generator/gun mu- 0. 0. 3500. 0. 0. -1000.
The polarizations are for photons and can be dropped.
KE seems to be sensibly computed if non-zero px py pz are entered.
px=py=pz=0 and KE!=0 generate an isotropic spread.
TB
Tim Bolton
Professor
High Energy Physics Group
Kansas State University
tbolton@ksu.edu
785-532-1664
________________________________
From: Stephen Jacob Sekula [mailto:sekula@mit.edu]
Sent: Wed 9/21/2005 12:43 AM
To: sekula@mit.edu
Cc: bw_sim@hep.uchicago.edu
Subject: Re: Generating muons as primary for veto system studies...
Hi Again,
I did a little more investigating on this muon generation issue. I replace "mu-"
with "e-" everywhere in my .mac file and re-ran the study. That worked perfectly
- all the primaries were e-. So, it looks like I need to concentrate on how the
particle gun handles muons...
Any more info would still be helpful.
Cheers,
Steve
Stephen Jacob Sekula wrote:
> Hi Folks,
>
> I need some help. I'm trying to test my addition to the RAT event tree
> (I wrote a processor for the veto system, etc.). To do this, I wanted to
> fire 1000 "cosmic ray" muons into the cave. I wanted to sample from a
> spectrum that was logarithmically flat in energy (10^2-10^6 MeV) and
> flat in zenith angle (cosTheta -1.0 - -0.3).
>
> I tried making a HEPEVT file, as for the IBD events. This wasn't
> successful, so instead I generated a .mac file with lines as follows:
>
> /generator/pos/set 9 "7275.89 6585.75 10000"
> /generator/vtx/set 17 "mu- -0.246024 0.769951 -0.588767 270.184"
> /run/beamOn 1
> /generator/pos/set 9 "9825.88 7919.56 10000"
> /generator/vtx/set 17 "mu- -0.39135 -0.220177 -0.893514 145.48"
> /run/beamOn 1
> /generator/pos/set 9 "9357.36 7233.58 10000"
> /generator/vtx/set 17 "mu- -0.546423 0.101814 -0.831298 577776"
> /run/beamOn 1
> .
> .
> .
>
> I did this 1000 times.
>
> This should have produced 1000 events with a primary being the muon.
> When I look at the root file - in particular, when I scan the primary in
> each event (and here I might have already made a mistake):
>
> root [3] T->Scan("mcparticle.pdgcode[0]")
> ************************
> * Row * mcparticl *
> ************************
> * 0 * 13 *
> * 1 * 13 *
> * 2 * 2112 *
> * 3 * 2112 *
> * 4 * 2112 *
> * 5 * 2112 *
> * 6 * 2112 *
> * 7 * 2112 *
> * 8 * 2112 *
>
> As you can see, the first two (for example) are muons. However, the next
> 998 events appear to have protons as primaries.
>
> I assumed that the structure of my .mac file was the problem. So,
> instead, I just ran this:
>
> /generator/pos/set 9 "7275.89 6585.75 10000"
> /generator/vtx/set 17 "mu- 0.0 0.0 -1.0 270.184"
> /run/beamOn 1000
>
>
> But I got something similar to the above in the ROOT file.
>
> I think my fundamental problem is that I've either misunderstood the way
> events are generated, or that I have misunderstood how particles are
> counted as "primary" in these events. However, it's also possible I've
> made some other mistake. Any help is very welcome!
>
>
> By the way, I want to say that so far I've found the documentation for
> RAT and the wiki to be excellent. I hope the above problem isn't covered
> in the docs -- I thought I'd read all of it before asking this here.
>
> Regards,
> Steve
>
>
-- +--------------------+-------------------------------------------+ | Stephen J. Sekula | http://www.slac.stanford.edu/~sekula | | Post-Doc | http://steve.cooleysekula.org/ | +--------------------+-----------------+-------------------------+ | MIT Laboratory for Nuclear Science | SLAC: (650)-926-8596 | +--------------------------------------+-------------------------+
This archive was generated by hypermail 2.1.6 : Wed Sep 21 2005 - 12:01:02 CDT