120 likes | 256 Views
Integrated Mechanical Design of 280m Off-Axis -and- CHEC for 280m On-Axis. Arie Bodek, Jesse Chvojka Kevin McFarland, Ray Teng University of Rochester T2K 280m WWV, March 2004. “Integrated Mechanical Design”.
E N D
Integrated Mechanical Design of 280m Off-Axis -and-CHEC for 280m On-Axis Arie Bodek, Jesse ChvojkaKevin McFarland, Ray TengUniversity of Rochester T2K 280m WWV, March 2004
“Integrated Mechanical Design” • Traditional design of a fixed target “active detector” is to surround it with separated calorimeters • Problems: • calorimeters are three dimensional “boxes” and may be hard to move • have to move whole calorimeter to access inner detector • complicated mechanical supports
The MINERnA Solution • Outer calorimeters (e.g., “photon catcher”, muon range/toroid, HCAL) are constructed with inner detector in planes… Inner, fully-active strips “Ring” EMCalorimeter Outer Detectormagnetized sampling calorimeter
The MINERnA Solution (cont’d) • The advantages of assembling a detector in planes are clear. Outer detector supports inner in a unified plane. • Complications: • planes are convenient to move, but floppy! • have to route fibers from inner strips “through” outer detector • To study details of this novel design, we are prototyping construction at Rochester
Prototyping Activities (Ray Teng) • Primarily working on fiber routing problem • built a 1/6 hexagon prototype to study Outer HCAL Plastic fiber routing sheet (50mil polypropylene) Pb Absorber (ECAL) Mock-up (one piece) of inner strips 2 meters
Prototyping Activities (cont’d) • Primarily workingon fiber routingproblem • getting outer andinner detectorfibers around theabsorber/frame Outer Det. Bars Plastic fiber routing sheet (50mil polypropylene) HCAL Abs. fibers must bend up (out of plane) and to outside of detector Inner Det. Bar
CHErenkov Counters forOn-Axis • Why CHEC? • we know that we want to monitor beam profile on-axis, but we also know that it is helpful to pick out higher energy neutrinos • more sharply peaked! • may carry information about Kaon contribution of beam, although Hiraide’s studies suggest this is better done off-axis • but it is expensive in $¥£€ to build a building for a neutrino spectrometer on axis (deep)
CHEC Conceptually… • A threshold Cerenkov detector is excellent for finding m above a certain energy • high momentum muons are also well correlated with incoming neutrino energies • can be relatively compact… so they fit in a “well” instead of a detector hall • But… • aren’t there lots of other things rattling around from neutrino interactions?
CHEC Conceptually (cont’d) • Detector has two parts… • scintillator counter at both ends to ensure MIP and only MIP and small angle • then the Cerenkov proper Threshold Cerenkov
CHEC can select muons… All Tracks Low Angle Tracks m other particles so select on the MIP peak at front and back of CHEC
CHEC correlation with Neutrino Energy real muons gm • Note strongcorrelation with neutrino energy • Low background • TO DO • demonstrate Cerenkov efficiency • demonstrate unfolding to neutrino energy from gm En background gm En