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Dark Matter Depth Task Force

Where shall we publish our White Paper??

Reference Link is a page where you can list journals or ideas

Particle Files

  • GeodmHomestakeCosmo Groom Parameterization 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.
  • 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. MUSUN+GEANT4
  • External Link 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.

Geometry Files

Choice of Analysis Cuts

LXe
  • Current Livetime = 2.12 years and Number of single NR after all cuts except muon veto = 0
  • veto on muon entering water shield
  • Energy ROI is 5 - 25 keVnr
  • veto on electron recoil energy < 50 keVee deposited in liquid Xe,
  • fiducial cut: r < 93cm & |z| < 84 cm,
  • multiples cut - σr < 3cm & σz < 0.2cm
Ge
  • Current Livetime = 169.1 years and Number of single NR after all cuts except muon veto = 26
  • veto on muon entering water shield
  • Energy ROI is 5-100 keVnr
  • Yield cut = no ER of more than 10%
  • single detectors of 10cm diam and 1 inch thickness, multiples down to 2 keVnr
LAr
  • Current Livetime = 6.41 years and Number of single NR after all cuts except muon veto = 0
  • veto on muon entering water shield,
  • Energy ROI is 50-100 keVnr (energy resolution 8%)
  • 55 cm from wall (resolution of a couple cm)
  • de-excitation gamma - fPrompt from inelastic scatter
  • multiples are included in the timing cut = >6 cm
GEANT4 Physics
  • To coordinate the simulations it has been agreed that we will try to ascertain which physics lists are used for each study. In general, we will continue to work with v4.9.3 P02 modified with new muon-nuclear before switching (mid-december) to v4.9.5 which intrinsically has this mu-nuclear interaction. It has been pointed out that it is best to not only use esoteric version and physics list names but also try to be clear about which physics is included. The table below contains information in this direction. Eventually, we hope to be able to relate in a concise way what all the physics processes included are so there can be no ambiguity.
Version Physics List(s) Accurate Mu-Nuclear available? Sheilding available?
v4.9.3 P02 QGSP_BERT_HP, Mu-Nuclear (not in release) not intrisically not intrinsically
v4.9.5 QGSP_BERT_HP OR Shielding yes yes
  • The way the physics lists work is that a single list is to be included at a time. The relevant lists which are available are listed in this page. These lists have been used starting in v4.9.4 with the exception that the QGSP_BERT_HP list has been used (with the new muon-nuclear interaction) with the backported v4.9.3 P02

White Paper Work

TABLE of Comparisons

Reference methods as follows

  • 0. The simple LXe Monte Carlo (4850 level) with isotropic angular distribution on a sphere (Monica)
  • 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 Soudan rock and a flat overburden, but has a good angular distribution of incoming neutrons.
  • 2. Best Model: Homestake MUSUN Muons + GEANT4, taking account of the geography and geology of the Homestake site prepared by Chao and Angie. Muons are then propagated through rock using GEANT4 v4.9.5 to produce neutrons and all secondaries.
  • 3. Homestake MUSUN Muons + FLUKA: Muons generated via MUSUN, but then propagated through the rock via FLUKA (Raul and Angie)
  • 4. Neutron Parameterization : Muons generated via MUSUN, but then creating a Neutron parametrization instead of all secondaries (Chao)
  • 5. Soudan MUSUN Muons + GEANT4: 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. (Angie and Melinda)
  • 6. The Neutron Multiplicity Meter (2100 mwe) with cosnθ distribution (partly derived from existing flux measurements)
Muons per sec per sq meter hitting the top of the water tank (downward) + spectrum (50GeV bins) if available
  • 4.4 E-5 (Simple LXe MC) Uses M&H muon flux rate at Homestake.
  • 4.4 E-5 (Groom on LXe geometry) Explicitly tied to M&H rate.
  • 6.46 E-5 (Homestake MUSUN + FLUKA on LXe geometry - Angie and Alex) Explicitly tied to Chao's MUSUN rate
  • 6.46 E-5 (Neutron parameterization for LXe geometry) Deduced by MUSUN+GEANT4
  • 6.46 E-5 (Best Model on GE geometry - Angie and Shaun) rhel6 Explicitly tied to Chao's MUSUN rate.
  • 6.46 E-5 (Best Model on LXe geometry - Angie) Explicitly tied to Chao's MUSUN rate.
  • 6.46 E-5 (Best Model on LXe geometry - Monica) 20120808_mu_water_spec.jpg Explicitly tied to Chao's MUSUN rate.
  • 6.46 E-5 (Best Model on LAr geometry - Chao)
Muons per sec per sq meter hitting all outer walls of the tank (from out to in)
  • 4.4 E-5 (Simple LXe MC)
  • 7.3 E-6 (Groom on LXe geometry)
  • 1.75 E-5 (Homestake MUSUN + FLUKA on LXe geometry - Angie and Alex)
  • 1.84 E-5 (Neutron parameterization for LXe)
  • 1.76 E-5 (Best Model on GE - Angie and Shaun) rhel6
  • 1.77 E-5 (Best Model on LXe - Angie)
  • 1.76 E-5 (Best Model on LXe - Monica)
  • 2.11 E-5 (Best Model on LAr geometry)
Neutrons (with KE > 100 KeV) per sec per sq meter hitting the top of the water tank (downward) + spectrum (all energies, 50MeV bins)
  • 1.7 E-6 (Simple LXe MC)
  • 1.9 E-6 (Groom on LXe geometry)
  • 1.16 E-6 (Homestake MUSUN + FLUKA on LXe geometry - Angie and Alex)
  • 2.91 E-6 (Neutron parameterization for LXe) Normalized to MUSUN muon rate and then each neutron is parameterized singly
  • 2.59 E-6 (Best Model on GE - Angie and Shaun) rhel6
  • 2.72 E-6 (Best Model on LXe - Angie)
  • 2.08 E-6 (Best Model on LXe - Monica)20120808_n_water_spec.jpg
  • 1.87 E-6 (Best Model on LAr - Chao)
Neutrons (with KE > 100 KeV) per sec per sq meter hitting all outer walls of the tank (from out to in) +spectrum (all energies)
  • 3.6 E-6 (Simple LXe MC) Uses M&H muon-induced neutron flux rate at Homestake.
  • 2.4 E -6 (Groom on LXe geometry)
  • 9.01 E-7 (Homestake MUSUN + FLUKA on LXe geometry - Angie and Alex)
  • 1.13 E-6 (Neutron parameterization for LXe) Normalized to MUSUN muon rate and then each neutron is parameterized singly
  • 2.27 E-6 (Best Model on GE - Angie and Shaun) rhel6
  • 2.05 E-6 (Best Model on LXe - Angie)
  • 1.83 E-6 (Best Model on LXe - Monica) 20120808_n_water_spec.jpg
  • 1.83 E-6 (Best Model on LAr)
Neutrons (with KE > 100 KeV) per sec per sq meter entering detector volume + spectrum
  • 3.4 E -10 (Simple LXe MC) Requires some energy deposition (NR or ER) in the liquid Xe since we did not store all events that pass into the detector
  • 5.9 E -7 (Groom on LXe geometry)
  • 3.23 E-7 (FLUKA on LXe geometry - Angie and Alex)
  • 1.00 E-8 (Neutron parameterization for LXe) singly thrown parameterized neutrons
  • 2.38 E-6 (Neutron parameterization for LXe) parameterized muons creating neutrons in the shield
  • 4.90 E-6 (Best Model on GE BLock only)
  • 5.97 E-7 (Best Model on GE Towers - Angie and Shaun) rhel6
  • 1.00 E-5 (Best Model on LXe - Angie) defined as Monica's below. When defined inside water shield, r=1.8m, rate is 2.77E-7
  • 1.26 E-5 (Best Model on LXe - Monica) 20120808_n_xe_spec.jpg Defined as neutron with E > 100
  • 5.48 E-6 (Best Model on LAr). R=1m & H=2m.
Events per sec that have at least one NR (no other cuts)
  • 5.44 E -8 (Simple LXe MC) for NR_dep > 5 keV_r; 5.42 E -8 for NR_dep > 10 keV_r
  • 4.9 E -5 (Groom on LXe geometry)
  • 1.13 E -8 (Neutron parameterization for LXe) singly thrown parameterized neutrons (NR_dep > 5 keV_r)
  • 5.84 E -5 (Neutron parameterization for LXe) parameterized muons creating neutrons in the shield(NR_dep > 5 keV_r)
  • 6.25 E -5 (Best Model on GE Block only) no identifiable cut, 10-100keV edep in Ge detectors
  • 4.96 E -6 (Best Model on GE towers - Angie and Shaun) rhel6, no identifiable cut, > 5keV edep in Ge detectors
  • 3.10 E -5 (Best Model on LXe - Angie) for edep>5keV.
  • 1.23 E -4 (Best Model on LXe - Monica) for NR_dep > 5 keV_r
  • 1.25 E -5 (Best Model on LAr - Chao) for NR_dep> 5 keV_r; 1.23E-5 for NR_dep>50 keV_r.
Events per sec that have at least one NR and are in the Energy ROI
  • 5.44 E -8 (Simple LXe MC) for NR_dep > 5 keV_r; 5.42 E -8 for NR_dep > 10 keV_r
  • 4.9 E -5 (Groom on LXe geometry)
  • 1.13 E -8 (Neutron parameterization for LXe) singly thrown parameterized neutrons (NR_dep > 5 keV_r)
  • 5.84 E -5 (Neutron parameterization for LXe) parameterized muons creating neutrons in the shield(NR_dep > 5 keV_r)
  • 4.28 E -6 (Best Model on GE Towers - Angie and Shaun) rhel6, no identifiable cut, 10-100keV edep in Ge detectors
  • 1.1 E -3 (Best Model on LXe - Angie) for edep>5keV. for 5-25keV cut, get 7.5E-4 events/s, no identifiable cut
  • 4.70 E -5 (Best Model on LXe - Monica)
  • 1.16E -7 (Best Model on LAr - Chao) for NR_dep within [50, 100] keV_r
Rate of Single WIMP candidates in entire volume (All analysis cuts except fiducial and veto)
  • 1.1 E -10 (Simple LXe MC) for NR_dep > 5 keV_r & Single Scatter cut ( σr < 3cm & σz < 0.2cm); 1.0 E -10 for NR_dep > 10 keV_r
  • 5.9 E -7 (Groom on LXe geometry)
  • < 4.26e-12 (Neutron parameterization for LXe) singly thrown parameterized neutrons with upper energy limit need limit removed
  • 7.26e-9 (Neutron parameterization for LXe) parameterized muons creating neutrons in the shield
  • 8.30 E-8 (Best model on Ge Towers - Angie and Shaun)
  • < 1.49 E - 8 (Best model on LXe - Monica) There are 0 events so I use the limit of 1 event in total livetime (~2.12 years) → need more stats
  • 1.60 E -8 (Best model on LAr - Chao) single NR_dep within [50, 100] keV_r (10 events in 19.81 years)
Rate of Single WIMP candidates in Fiducial Volume (ignore veto)
  • 3.2 E -12 (Simple LXe MC) WIMP Candidate: pass NR, Single Scatter, Elastic, and Fiducial Cut. NR cut: NR deposits in liquid Xe: 5 - 25 keVr. Single Scatter Cut: σr < 3cm & σz < 0.2cm, Elastic Cut: ER < 50 keVee in liquid Xe, Fiducial Cut: r < 93cm & |z| < 84 cm
  • < 1.49 E - 8 (Best model on LXe - Monica) There are 0 events so I use the limit of 1 event in total livetime (~2.12 years) → need more stats
  • < 1.60 E -9 (Best model on LAr - Chao) Set up a limit for livetime 19.81 years.
Veto ratio (vetoed : unvetoed) for single WIMP candidates in the fiducial volume
  • 117:0 (Best model on Ge Towers - Angie and Shaun) veto definition: muon (>100MeV) enters or exits water tank)
  • 0:0 (Best model on LXe - Monica)
Veto ratio for multiple NR. (not applicable for liquid argon)
  • 9081:9 (Best model on Ge Towers - Angie and Shaun)
  • 6978:0 (Best model on LXe - Monica) Muon entering water tank must have at least 1 GeV energy

Other Relevant Studies

  • Description of the Geant4 v Fluka study. Refined from the original Feb 2011 charge.
  • GEANT4 vs FLUKA Comparison Study of mu-induced neutron yield (Empl, Villano)

Meetings and Decisions

Dec 5 2013

Nov 25 2013

Oct 28, 2013

Oct 21, 2013

Oct 14, 2013

Sept. 30, 2013

Aug 8, 2013

July 18, 2013

July 11, 2013

May 30, 2013

May 23, 2013

May 9, 2013

April 18

February 7, 2013

January 31, 2013

December 13, 2012

November 15, 2012

November 1, 2012

October 4, 2012 Status Reports

September20, 2012 Teleconference: Presentations

August 23, 2012 Teleconference: Presentations

August 9, 2012 Teleconference: Presentations

July 12, 2012 Teleconference: Presentations

June 28, 2012 Teleconference: Presentations

May 24, 2012 Teleconference: Presentations

May 10, 2012 Teleconference: Presentations

April 19, 2012 Teleconference: Presentations

April 5, 2012 Teleconference: Presentations

March 1, 2012 Task Force Teleconference: Presentations

Feb 2, 2012 Task Force Teleconference: Presentations

Jan 5, 2012 Task Force Teleconference: Presentations

Dec 19 Task Force Teleconference: Presentations

Nov 12 AARM Mtg: Dark Matter Depth Task Force

Oct 31 Task Force Teleconference: Detailed List of the Jobs assigned

  • Minutes and job list found here
dm_task_force.txt · Last modified: 2014/05/27 13:34 by ss507