E898 kaon monitoring

Projection of muons from front face of gunbarrel back to beginning of 8-inch pipe. Muon energy .GT. 0.5 GeV at gunbarrel. First page (black dots): "Dirt muons" (More than 0.5 GeV energy loss before hitting gunbarrel. Second page (red): "clean" muons (less than 5 MeV energy loss). Green circle: Outline of pipe wall. Blue circle: maximum collimator acceptance.

Same as above, with helium in pipe. Note that this is based on 36% of the statistics above. (Also, each clean muon on average carries about 5 times the weight of each dirt muon.)

Radius-squared of upstream muon projection to beginning of 8-inch pipe, same cuts as above: AIR and HELIUM. Note that the collimator effectively selects muons with R**2<51 cm in this projection. Also, the entries are properly weighted.

Uranium plates available from CERN: PDF

GEANT drawing of LMC in beamline

Energy of K and pi decays at 7 degrees.

muon origin for K and pi decays.

Muon gas versus kaon decay Monte Carlo studies:

Muon angle and radii at gunbarrel, origin versus energy loss in gunbarrel.

The following files (Color codes for the first four plots are explained on the first page) show:

1) Y vs. X position at Z=-1850 cm -- near opening

in decay pipe -- for muons with p.gt.0.5 GeV which hit gunbarrel at R.lt.2cm;

2) Radius at Z=-1850 for same muons.

3) Radius**2 at Z=-1850 vs. tan(theta) for same muons.

4) Radius**2 at Z=-1850 for same muons.

5) Radius**2 at gunbarrel (Z=-200) for non-dirt muons with P.gt.0.5 GeV.

6) Radius**2 at gunbarrel (Z=-200) for non-dirt muons with any momentum.

7) Radius**2 at gunbarrel (Z=-200) for any muons which hit gunbarrel.

FILES: Muon gas MC, Kaon decay MC (now full statistics).

For the three kaon-decay muons which make it down the 0.5-cm gunbarrel hole, this plot shows the Y vs. X positions where the muons were placed in the 8" tube.

Particle flux through the 8" tube at various Z positions.

Origins of >50 MeV charged particles which enter various parts of the 8" tube. Y vs. Z Y vs. X

Origins of ALL particles which enter various parts of the 8" tube. (3.2 MB each) Y vs. Z Y vs. X

Current proposed layout of 14 foot LMC enclosure, with detector components removed. Only civil construction elements shown. PostScript (good quality) JPEG (lower quality)

Description of angle of 8" LMC pipe relative to decay pipe. PostScript (good quality) JPEG (lower quality)

Current proposed layout of 14 foot LMC enclosure. PostScript (good quality) JPEG (lower quality)

Obsolete proposed layout of 14 foot LMC enclosure. PostScript (good quality) JPEG (lower quality)

Star densities in the downstream dump region. Note the nonstandard scale.

:Star densities in the upstream dump region.

:Star densities in the upstream dump region, with a 40cm x 200cm tungsten slab outside decay pipe.

Survival probability as a function of muon energy and number of 10cm (Z) x 10cm (R) tungsten range disks, for muoms generated down the hole..

Survival probability as a function of muon energy and number of 10cm (Z) x 5cm (R) tungsten range disks, for muoms generated down the hole..

Angle and muon momentum spectra from pi->mu nu decays.

Angle and muon momentum spectra from K->mu nu decays.

(From Joe) P_T spectra. Page 1 is the P_T spectrum of pions and kaons in the beam. Page 2 is the P_T spectra for muons from K and pi decays. This spectrum includes the effects of both beam divergence and decay Q-value..

Eric D. Zimmerman (edz@fnal.gov)