Testing cold dark matter with the HI velocity function Aaron A. - - PowerPoint PPT Presentation

Testing cold dark matter with the HI velocity function

Aaron A. Dutton

Research Scientist, New York University Abu Dhabi Gas in Galaxies, Malta, October 2017

NIHAO X - Macciò, Udrescu, Dutton, Obreja, Wang, Stinson, Kang 2016, MNRAS

Cold Dark Matter works on large scales

Tegmark et al 2004

4

• rders of

magnitude in scale

Oman et al. 2015

Cold Dark Matter fails on small scales

4.6 kpc

Discrepancy: Factor ~2 in velocity ⇒ factor ~ 4 in mass

SN driven gas outflows can expand the dark matter halo

NIHAO XIV - Santos-Santos et al. 2017

e.g., Navarro, Eke, Frenk 1996; Read & Gilmore 2005; Mashchenko et al. 2006, 2008; Pontzen & Governato 2012; Di Cintio et al. 2014a,b; Chan et al. 2015; Trujillo-Gomez et al. 2015

Cold Dark Matter works on small scales

Large radii less sensitive to cusp-core issue

NIHAO XIV - Santos-Santos et al. 2017 Walter & Brinks 1999

W50=110 W20=125

HI Flux los Velocity [km/s]

The HI Velocity Function

HIPASS (Zwaan et al. 2010) ALFALFA (Papastergis et al. 2011) Dist < 220 Mpc LOCAL VOLUME (Klypin et al. 2015) Dist < 10 Mpc

Velocity [km/s] dN/dlogV [h3Mpc-3]

0.5 W50 uncorrected for inclination

dN/dlogV [h3Mpc-3] Velocity [km/s]

Planck WMAP7

At fixed V: CDM has too many low mass haloes x6 dNcdm/dlogV ~ V-2.9 dNobs/dlogV ~ V-1.0

Local Volume d<10 Mpc Klypin et al. 2015

0.5 W50 uncorrected for inclination

Cold Dark Matter fails on small scales

dN/dlogV [h3Mpc-3] Velocity [km/s]

Planck WMAP7

x2 dNcdm/dlogV ~ V-2.9 dNobs/dlogV ~ V-1.0

Local Volume d<10 Mpc

At fixed N: CDM velocity is too high x4

Klypin et al. 2015

Cold Dark Matter fails on small scales

Do you think this is true or false?

Vmax = 0.5 W50

Key Assumption:

CDM wrong

⇒

If CDM corrrect

⇒

600 kpc/h 60 kpc/h 6 Mpc/h Gas Gas Gas 91 cosmological zoom-in hydro simulations with gasoline (SPH)

600 kpc/h 60 kpc/h 6 Mpc/h Gas Gas Gas 91 cosmological zoom-in hydro simulations with gasoline (SPH)

0.0 0.2 0.4 0.6 0.8 1.0 M [M ] 0.0 0.2 0.4 0.6 0.8 1.0 104 105 106 107 108 109 1010 1011 z=0

simulated galaxy z=0 Moster+13 z=0 Behroozi+13 z=0 Kravtsov+ (2014)

z=1

simulated galaxy z=1 Moster+13 z=1 Behroozi+13

109 1010 1011 1012 104 105 106 107 108 109 1010 1011 z=2

simulated galaxy z=2 Moster+13 z=2 Behroozi+13

109 1010 1011 1012 z=4

simulated galaxy z=4 Moster+13 z=4 Behroozi+13

NIHAO I - Wang, Dutton, Stinson et al. 2015 Stellar Mass [M⊙] Halo Mass [M⊙]

log(Neutral Gas) log(Stellar Mass)

ALFALFA (Huang et al. 2012)

Data from NIHAO XII - Dutton et al. 2017

log(Neutral Gas) log(Stellar Mass)

ALFALFA (Huang et al. 2012)

Data from NIHAO XII - Dutton et al. 2017

12 6 7 8 9 10 11 log (MHI/M) −1 1 2 log (RHI/kpc)

NIHAO Swaters 1999 Swaters 1999

횺(RHI)= 1 M⊙/pc2 NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 log(HI Mass) log(HI Size / [kpc])

NIHAO XIII: Clumps Tobias Buck (Talk tomorrow) NIHAO VIII: CGM Thales Gutcke (see Poster)

300.0 13 14 15 16

0.001L ∗ <L <0.1L ∗

300.0 13 14 15 16

log10 1HI [cP−1 ] 0.1L ∗ <L <L ∗ 50 100 100 IPpact 3araPeter [Npc]

13 14 15 16

L ∗ <L <7L ∗ 10kpc <b <100kpc 100kpc <b <100kpc

−3.0 −2.5 −2.0 −1.5 −1.0 −0.5 0.0 0.5 1.0

log /// ∗ 100kpc <b <300kpc

U-band SFR Gas rgb

NIHAO LCDM simulations form reasonable galaxies

145 147

los Velocity [km/s] HI Flux los Velocity HI Flux

−200−100 100 200

Average Maximum Flux

50% W50

Mock HI linewidth

Maximum Circular Velocity of DMO simulation

1.5 2.0 2.5 log

• VDM

max/km s−1

0.5 1.0 1.5 2.0 2.5 log

• V50/km s−1

log10(Vmax DMO) [km s-1] log10(0.5 W50) [km s-1]

HI linewidths vs Vmax of dark matter only

WMAX

50

145 168

g5.02e11 WMEDIAN

50

145 147 −200−100 100 200

WMIN

50

145 46

100 projections per galaxy NIHAO X - Macciò, Udrescu, Dutton, et al. 2016

1.5 2.0 2.5 log

• VDM

max/km s−1

0.5 1.0 1.5 2.0 2.5 log

• V50/km s−1

log10(Vmax DMO) [km s-1] log10(0.5 W50) [km s-1] 100 projections per galaxy NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 Klypin was right 0.5W50=VmaxDMO

Cold Dark Matter fails on small scales

1.5 2.0 2.5 log

• VDM

max/km s−1

0.5 1.0 1.5 2.0 2.5 log

• V50/km s−1

log10(Vmax DMO) [km s-1] log10(0.5 W50) [km s-1] 100 projections per galaxy NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 Klypin was right 0.5W50=VmaxDMO CDM is in trouble?

HI linewidths vs Vmax of dark matter only

1.5 2.0 2.5 log

• VDM

max/km s−1

0.5 1.0 1.5 2.0 2.5 log

• V50/km s−1

log10(Vmax DMO) [km s-1] log10(0.5 W50) [km s-1] NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 Klypin was right 0.5W50=VmaxDMO CDM is in trouble?

HI linewidths vs Vmax of dark matter only

100 projections per galaxy

1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 log

• V50/km s−1

−2 −1 1 2 log

• dN/dlog(V50)/h3Mpc−3

NIHAO Klypin et al. 2015 Klypin et al. 2015 uncorrected LCDM Klypin et al. 2015

log10(0.5 W50) [km s-1] dN/dlogV [h3Mpc-3] NIHAO X - Macciò, Udrescu, Dutton, et al. 2016

Cold Dark Matter works on small scales

1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 log

• V50/km s−1

−2 −1 1 2 log

• dN/dlog(V50)/h3Mpc−3

NIHAO Klypin et al. 2015 Klypin et al. 2015 uncorrected LCDM Klypin et al. 2015

log10(0.5 W50) [km s-1] dN/dlogV [h3Mpc-3] NIHAO X - Macciò, Udrescu, Dutton, et al. 2016

Cold Dark Matter works on small scales

How is this possible?

=72 km/s 61 50 30 8 mass loss (85%) HI extent (82%) projection (60%) Dutton et al. in prep

CDM is consistent with the HI Velocity Function

• W50/2 ≈ VmaxDMO for Milky Way mass galaxies
• W50/2 ≪ VmaxDMO for dwarf galaxies
• 1. Mass loss (~15%)
• 2. HI extent (~20%)
• 3. Non-circular motions (~30%)
• 4. Projection (~30%)

}

most dwarfs are NOT thin rotating disks

Radial Acceleration Relation

McGaugh et al. 2016

Observed Acceleration (V2/r) [m/s] Acceleration due to baryons (V2bar/r) [m/s]

NIHAO simulations Dutton et al. in prep

• 0.4

0.8 1.2 1.6 2.0 2.4 2.8 log(V20/km s−1) 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 W50/W20

NIHAO Bradford et al. 2016 W50/W20 = 0.656 W20 = W50 + 25

NIHAO X - Macciò et al. 2016

HI velocity profile shape depends on mass