CPLUOS Astrophysics team meeting

Friday 20 Jan 2023, 14:00 → 15:20 Asia/Seoul

물리학과

https://uos-ac-kr.zoom.us/j/8264902652

COSMOLOGY

1 Hyeonmo's Report_Planar System Generation

Speaker: Hyeonmo Koo (University of Seoul)

20230120.pptx

Planar System Generation

• Refer to "Analyzing Planar Galactic Halo Distributions with Fuzzy/Cold Dark Matter Models.
• Each Planar System has a quantity of the following.
  • Number of Halo(Hernquist Profile Seed): 100
  • Each mass of Halo(Seed): 𝜋×10⁸𝑀⊙
  • Profile of System: Plummer Profile 𝜌𝑟 = (3𝑀₀/4𝜋𝑎³)(1+r²/a²)^(-5/2)
  • Half-Light Radius of System: 𝑎 = 13.6 kpc
  • Radius Cut of System: 𝑅_max  = 40.8 kpc
  • 𝑣_ini  = 𝑞₁𝑣_P+𝑞₂𝑣±
    • q₁  = randomness
    • 𝑣_P: Random velocity of equillibrium plummer model
      • q₁ = 0.25, 0.30, 0.35, 0.40, 0.45
      • Z = 51, 52, 53, 54, 55
      • Whatever, the spin parameter λ ≅ 0.0422±0.0050
    • 𝑣±: Rotational velocity
• Comparison of CDM and FDM plots
• Boxsize = 204 kpc, resolution = 900
  • We got coordinates of each cell whose density is larger than 10⁷ M⊙/kpc³, in other words, M_cell ≥ 10⁷×(204/900)³ M⊙ ≅ 1.164×10⁶ M⊙.
  • Then, clustered with DBSCAN algorithm: Linking length 1.4 kpc and minimum particles per each cluster 10 (except centroid).
  • Black circles are the center of each clusters.
  • q₁ = 0.25, q₂ = 0.75, Z = 51, t = 0.0 Myr ~ 1470.0 Myr
    • x [kpc]-y [kpc] graph (rotation difference)
    • x [kpc]-z [kpc] graph (rotation difference)
• We got the ellipticity from the eigenvalue of inertia tensor
  • I_ij  = c/a = (min(eigenvalues)/max(eigenvalues))^1/2
  • Planar structure of cdm: Time [Myr]-c/a graph
    • q₁ = 0.25
    • q₁ = 0.30
    • q₁ = 0.35
    • q₁ = 0.40
    • q₁ = 0.45
  • Planar structure of fdm: Time [Myr]-c/a graph
    • q₁ = 0.25
    • q₁ = 0.30
    • q₁ = 0.35
    • q₁ = 0.40
    • q₁ = 0.45
  • q₁ = 0.25: Time [Myr]-c/a graph
    • CDM
    • FDM
  • q₁ = 0.30: Time [Myr]-c/a graph
    • CDM
    • FDM
  • q₁ = 0.35: Time [Myr]-c/a graph
    • CDM
    • FDM
  • q₁ = 0.40: Time [Myr]-c/a graph
    • CDM
    • FDM
  • q₁ = 0.45: Time [Myr]-c/a graph
    • CDM
    • FDM

2 Young's report. FoF and MST algorithm

Speaker: Young Ju

3 Hannah's Report

Speaker: Hannah Jhee (University of Seoul)

4 Seyeon's Report - CLML

Speaker: Se Yeon Hwang (Universe of Seoul)

5 Sumi's report

Speaker: Sumi Kim (University of Seoul)

6 Dr.Sabiu's Report

Speaker: Dr Cristiano Sabiu (University of Seoul)

7 Discussion