NnL analysis meeting-20210331

nnΛ Analysis Meeting

Information

• 21:00 - 26:20 March 31, 2021 (JST)
• Participants: Nue, Liguang, Pete, Joerg, Toshi, Sho, Bishnu, K.N.Suzuki, K. Itabashi, K. Okuyama, T. Akiyama, Y. Toyama +
• via BlueJeans

Reports

Hampton

(10 min) Summary by L. Tang

• Matrix tuning
  • Angle resolution is limited due to the hole size.
    → Δθ = 3.4 mrad
• The intrinsic mass resolution
  • Large A dependence because of the large angle contribution.

(20 + 10 min) Details by B. Pandey

Presentation file = NNL_MArch31_Bishnu.pdf
Supplement (angle that he used) = Angle_conversion.pdf

• Al peaks are involved in the tuning.

Kyoto

(5 min) Japanese Analysis Summary by T. Gogami

Presentation file = JLabMeeting_20210331_gogami.pdf
Supplement (angle definition) = JLabMeeting_20210331_gogami_2.pdf

1. Expected mass resolution
2. Momentum tuning with Λ(H), Σ(H), and Λ(T)
3. Cross section

(25 + 10 min) Kyoto analysis by K.N. Suzuki

• Resolution study by Geant4 simulation
  • Angle resolution: Δ θ = 1.2 mrad in σ
  • Missing mass resolution; no strong mass dependence was estimated.
• Systematic error on B_Λ
• Cross section analysis

Tohoku

(10 + 5 min)Tohoku analysis (1) by S. Nagao

Presentation file = nagao20210331_JLab_analysis_meeting.pdf

• The intrinsic mass resolution
• Tuning with Al data

(20 + 10 min) Tohoku analysis (2) by K. Itabashi

• Showed how analyses are different among the analysis groups
• Spectra comparison

Discussion

• What needs to be done / checked ?
  • H contamination → Shape of Λ may be better to be asymmetry to discuss about the Σ bound region. (→ Hampton)
  • Test of single peak inclusion of the Al data for the tuning → any other peaks grow? (→ Japan)
  • Information about the matrix tuning and matrices (which have not been involved Al tuning at all) will be provided to Japanese group (→ Hampton)

• Questions to Hampton group
  • How to estimate
    • the angular resolutions (Δ x' and &Delta y')? → Hole size
    • QF Λ shape including the Σ ?
      → SIMC (³He target) + scaling (How much the scaling factor as a function of the binding energy?
      → Used the accidental shape. In addition, the result needs to be compared with Kosuke's SIMC simulation )
      → How much the ratio of Λ to Σ?
    • the differential cross sections and their errors (acceptance correction etc.)? → ratio to QF Λ (assumed to be 400 nb/sr).

References for discussion

• from Hampton
  • TECHNIQUE_OF_MATRIX_TUNE_Tang2021Mar.pdf (Mar 15, 2021)
  • Resolution_optical_tune_Tang2021Mar.pdf (Mar 15, 2021)
• from Tohoku
• from Kyoto
  • Mar 24, 2021: Simple test of matrix tuning by using simulated data: JLabMeeting_20210324_gogami.pdf
  • June 18, 2020: Missing mass spectra: JLabMeeting_20200618_gogami.pdf
  • May 01, 2020: Angle resolution (Summary of Suzuki’s study): nnL_AnalysisNote_20200501_gogami.pdf
  • Apr 24, 2020: Comments on the missing mass resolution： JLabMeeting_20200424_gogami.pdf
  • Apr 21, 2020: Missing mass resolution (Fake peak study by Itabashi is found in the last part): nnL_AnalysisNote_20200421_gogami.pdf
  • Apr 16, 2020: How to treat angle resolution for the intrinsic resolution estimation (here, the worse resolution for angle is used compared to the recent values though)： JLabMeeting_20200416_gogami.pdf
  • Mar 13, 2020: The expected resolution, the number of events, items to be reexamined (p. 31, 32): JLabMeeting_20200313_gogami.pdf