Explaining Diverse Rotation Curves of Spiral Galaxies with - PowerPoint PPT Presentation

Explaining Diverse Rotation Curves of Spiral Galaxies with Self-Interacting Dark Matter (SIDM) Tao Ren (UC Riverside) @ DPF 2017 with Hai-Bo Yu (UCR), Anna Kwa, Manoj Kaplinghat (UCI)

Data Source: SPARC Diversity in Rotation Curves 1606.09251 100 60 80 50 V circ [ km / s ] V circ [ km / s ] 40 60 30 40 V f ~ 55.9 - 62.2 km / s 20 UGCA442 V f ~ 79.5 - 87.6 km / s UGC05721 UGC08550 20 UGC08286 10 UGC07690 UGC06399 DDO170 F583 - 1 0 0 0 5 10 15 0 2 4 6 8 10 12 Radius [ kpc ] Radius [ kpc ] 300 140 120 250 100 V circ [ km / s ] 200 V circ [ km / s ] 80 150 60 V f ~ 134. - 144. km / s V f ~ 211. - 247. km / s 100 NGC2403 40 UGC06786 F571 - 8 IC4202 NGC3972 50 20 UGC09133 NGC3917 NGC6195 0 0 0 5 10 15 20 0 10 20 30 40 50 60 70 Radius [ kpc ] Radius [ kpc ]

Headache for Cold Dark Matter (CDM) 200 V circ ( 2 kpc ) [ km / s ] DM 100 + Baryon 50 CDM only 20 50 100 200 V f [ km / s ] Halo Mass (M200) M 200 c 200 = (10 0 . 905+ δ ⇤ 0 . 11 )( ) � 0 . 101 & 10 12 ∗ h � 1 M � Concentration (c200) A. A. Dutton et al. (2014)

Examples for the Trouble K. A. Oman et al. (2015) 😆 V circ [km/s] 😥 Radius [kpc]

SIDM & CDM Density Profile ������ ���� � ��� ������� ������� 10 12 𝜍 (r) [M ⦿ /kpc 3 ] 10 10 r )) / � 2 ∼ exp [ − ( Φ DM ( ~ r ) + Φ B ( ~ v ] / PDF NFW 10 8 r ) / � 2 ∼ exp [ − Φ DM ( ~ v ] ρ ( ) SIDM 10 6 10 4 0.01 0.10 1 10 100 Radius [kpc] How SIDM works: Self-Interaction + Baryon Effect + M200-c200 Relation CDM : 1504.01437

SIDM Fitting Examples Kamada, Kaplinghat, Pace, Yu, (2016) 100 60 80 50 V circ [ km / s ] V circ [ km / s ] 40 60 30 40 V f ~ 55.9 - 62.2 km / s 20 V f ~ 79.5 - 87.6 km / s UGCA442 UGC05721 UGC08550 20 UGC08286 10 UGC07690 UGC06399 DDO170 F583 - 1 0 0 0 2 4 6 8 10 12 0 5 10 15 Radius [ kpc ] Radius [ kpc ] 300 140 120 250 100 200 V circ [ km / s ] V circ [ km / s ] 80 150 60 V f ~ 134. - 144. km / s V f ~ 211. - 247. km / s 100 NGC2403 UGC06786 40 F571 - 8 IC4202 50 NGC3972 UGC09133 20 NGC3917 NGC6195 0 0 0 10 20 30 40 50 60 70 0 5 10 15 20 Radius [ kpc ] Radius [ kpc ]

SIDM: the “Aspirin” for “Headache” 😥 V circ [km/s] SIDM 80 100 F583 - 1, δ :0. IC2574, δ : - 2.5 80 60 😄 60 40 40 20 20 0 0 0 2 4 6 8 10 12 0 5 10 15 Radius [kpc]

Fitting to 120 Galaxies 100 SIDM ( 120 / 120 ) Number of galaxies CDM ( 113 / 120 ) 80 60 40 20 0 0 2 4 6 8 10 χ 2 / d.o.f

Radial Acceleration Relation McGaugh, Lelli, Schombert, Pawlowski (2017) - 8 log ( g tot ) [ m / s 2 ] - 9 - 10 - 11 g bar g obs = 1 − e − √ g bar /g † - 12 - 12 - 11 - 10 - 9 - 8 log ( g baryon ) [ m / s 2 ] 400 g † = 1.2 × 10 - 10 m / s 2 Number of Points σ = 0.106 dex 300 200 100 0 - 0.6 - 0.4 - 0.2 0.0 0.2 0.4 0.6 Residuals ( dex ) From Diversity to Uniformity

Summary Diversity in rotation curves of spirals Trouble of CDM How SIDM works : Self-Interaction+Baryon effect+M200-c200 Fitting results for 120 galaxies Radial acceleration relation

Back Up Slides & Supporting Information

Self-interaction & Velocity Dispersion

Velocity Dependent Cross Section Kaplinghat, Tulin, Yu (2015)

SIDM Model Example & Parameter Measurement

Possible Too-Big-To-Fail Problem in SIDM 200 100 V flat [ km / s ] 50 100 80 60 V flat [ km / s ] 40 20 20 20 40 60 80 100 10 V max [ km / s ] 20 50 100 200 V max [ km / s ]