Table of Contents
Agenda for the December 19, 2011 DM Depth Task Force
EVO meeting at 3 pm central time Look under Universe for DM Task Force, with password “depth” or connect by phone at 1 626 395 2112 with ID = 446 1036# and Pwd 8461#
Back to Depth Task Force wiki startpage
Converging on the same physics list
- Presentation by Anthony.
- Discussion.
Getting on the same page
- New MC at Homestake with G4 4.9.5 + Mu-nuc + MUSUN muons (parameterized muon spectrum) - Chao
- Input files (Angie) and first comparison with Homestake parameterization (Chao)
- Comparing Livetimes & benchmark numbers: Fill in the TABLE below BEFORE the meeting so we can discuss. We will start with quick presentation of what you did, in order to interpret the numbers. If you want to include a few slides with pictures or explanations, you can plug them into these first four bullet points.
- LZ geometry with G4 4.9.3 P02 (good mu-nuc + shielding list) - Angie
- LZ geometry with isotropic M&H thrown - Monica
- LZ geometry at Brown with Angie's files - David, Monica
- LZ geometry at Homestake with parametrization Chao's Presentation
We will refer to these “methods” by the following numbers and letters. Numbers refer to particle files, letters to parametrizations.
- 1. “Groom” Parametrization of muons at Homestake depth, propagated through rock using GEANT4 v4.9.3 P02 with new mu-nuclear to produce neutrons and all secondaries. Assumes a flat overburden, but has a good angular distribution of incoming neutrons. Uses “Soudan” rock.
- 2. Muons generated via MUSUN, taking account of the geography and geology of the Homestake site. Muons then propagated through rock using GEANT4 v4.9.5 to produce neutrons and all secondaries. Not yet generated by Chao.
- 3. Muons generated via MUSUN, taking account of the geography and geology of the Soudan site. Muons then propagated through rock using GEANT4 v4.9.3 P02 with new mu-nuclear to produce neutrons and all secondaries. Done by Angie, not yet filtered for Melinda
- A. The LZ Monte Carlo (4850 level) with isotropic angular distribution on a sphere
- B. The Neutron Multiplicity Meter (2100 mwe) with cosnθ distribution (partly derived from existing flux measurements)
- C. Muons generated via MUSUN, taking account of the geography and geology of the Homestake site. Neutron parametrization created from this. Done by Chao.
TABLE
Fill these out by referring to the method. Fill out numbers and put links to spectra. Templates are included for the first few entries. Please replace with the correct numbers.
Muons per sec per sq meter hitting the top of the water tank (downward) + spectrum if available
- 4.4 E-5 (File 1 on LZ geometry - Angie) Explicitly tied to M&H rate.
- 4.4 E-5 (Method A - Monica) Uses M&H muon flux rate at Homestake.
- 6.46 E-5 (Method C - Chao) Deduced by MUSUN+GEANT4
Muons per sec per sq meter hitting all outer walls of the tank (from out to in)
- 7.3 E-6 (File 1 on LZ geometry - Angie)
- 4.4 E-5 (Method A - Monica) Uses M&H muon flux rate at Homestake.
- 1.84 E-5 (Method C - Chao) Deduced by MUSUN+GEANT4
Neutrons (with KE > 100 KeV) per sec per sq meter hitting the top of the water tank (downward) + spectrum (all energies)
- 1.9 E -6 (File 1 on LZ geometry - Angie)
- 1.7 E-6 (Method A - Monica) Uses M&H muon-induced neutron flux rate at Homestake and accounts for top and bottom of the water tank.
- 2.91 E-6 (Method C - Chao) MUSUN+GEANT4
Neutrons (with KE > 100 KeV) per sec per sq meter hitting all outer walls of the tank (from out to in) +spectrum (all energies)
- 2.4 E -6 (File 1 on LZ geometry - Angie)
- 3.6 E-6 (Method A - Monica) Uses M&H muon-induced neutron flux rate at Homestake.
- 1.13 E-6 (Method C - Chao) MUSUN+GEANT4
Neutrons (with KE > 100 KeV) per sec per sq meter entering detector volume + spectrum
- 5.9 E -7 (File 1 on LZ geometry - Angie)
- 3.4 E -10 (Method A - Monica) This value though has the caveat that there must be some energy deposition (NR or ER) in the liquid Xe since we did not store all events that pass into the detector.
- 1.00 E-8 (Method C - Chao) MUSUN+GEANT4
Events per sec that have at least one NR
- 4.9 E -5 (File 1 on LZ geometry - Angie)
- 5.44 E -8 (Method A - Monica) for NR_dep > 5 keV_r; 5.42 E -8 for NR_dep > 10 keV_r
- 2.56 E -9 (Method C - Chao) MUSUN+GEANT4 → Secondary neutron only
Rate of single NR (without including info from any possible veto)
- 5.9 E -7 (File 1 on LZ geometry - Angie)
- 1.1 E -10 (Method A - Monica) for NR_dep > 5 keV_r & Single Scatter cut; 1.0 E -10 for NR_dep > 10 keV_r
- < 4.26e-12 (Method C - Chao) MUSUN+GEANT4 → Secondary neutron only
Rate of Single WIMP candidates (ignore veto)
- 3.2 E -12 (Method A - Monica) see slides;
Veto ratio (vetoed : unvetoed) for single NR (add your veto "rules")
- 69:2 (Method A - Monica) single NR corresponds to NR > 5 keV_r and single scatter cut. Veto corresponds to applying all cuts (NR cut, Single Scatter, Elastic, and Fiducial)
Veto ratio for multiple NR.
- 33506:10 (Method A - Monica) multiple NR corresponds to NR > 5 keV_r. Veto corresponds to applying NR, Elastic, and Fiducial cut
Soudan Benchmarking
- Status of filtered files - Melinda, Angie
- Livetime numbers: 6e7 muons → 35 days → ~60k events with neutrons hitting the N detector geometry