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 NIHAO X - Macciò, Udrescu, Dutton, Obreja, Wang, Stinson, Kang 2016, MNRAS Gas in Galaxies, Malta, October 2017

C old D ark M atter works on large scales 4 orders of magnitude in scale Tegmark et al 2004

C old D ark M atter fails on small scales Discrepancy: Factor ~2 in velocity ⇒ factor ~ 4 in mass 4.6 kpc Oman et al. 2015

C old D ark M atter works on small scales SN driven gas outflows can expand the dark matter halo 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 NIHAO XIV - Santos-Santos et al. 2017

Large radii less sensitive to cusp-core issue Walter & Brinks 1999 HI Flux W 50 =110 W 20 =125 los Velocity [km/s] NIHAO XIV - Santos-Santos et al. 2017

The HI Velocity Function LOCAL VOLUME dN/dlogV [h 3 Mpc -3 ] (Klypin et al. 2015) Dist < 10 Mpc ALFALFA (Papastergis et al. 2011) Dist < 220 Mpc HIPASS (Zwaan et al. 2010) Velocity [km/s] 0.5 W 50 uncorrected for inclination

C old D ark M atter fails on small scales Klypin et al. 2015 Local Volume Planck dN cdm /dlogV ~ V -2.9 dN/dlogV [h 3 Mpc -3 ] d<10 Mpc WMAP7 x6 dN obs /dlogV ~ V -1.0 At fixed V: CDM has too many low mass haloes Velocity [km/s] 0.5 W 50 uncorrected for inclination

C old D ark M atter fails on small scales Klypin et al. 2015 Local Volume Planck dN cdm /dlogV ~ V -2.9 d<10 Mpc Velocity [km/s] WMAP7 dN obs /dlogV ~ V -1.0 x2 x4 At fixed N: CDM velocity is too high dN/dlogV [h 3 Mpc -3 ]

⇒ ⇒ Key Assumption: V max = 0.5 W 50 Do you think this is true or false? CDM wrong If CDM corrrect

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

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

NIHAO I - Wang, Dutton, Stinson et al. 2015 1 . 0 10 11 z=0 z=1 10 10 10 9 Stellar Mass [M ⊙ ] 0 . 8 10 8 10 7 simulated galaxy 10 6 z=0 Moster+13 simulated galaxy 0 . 6 z=0 Behroozi+13 z=1 Moster+13 10 5 z=0 Kravtsov+ (2014) z=1 Behroozi+13 10 4 10 11 z=2 z=4 0 . 4 10 10 10 9 10 8 10 7 0 . 2 10 6 simulated galaxy simulated galaxy z=2 Moster+13 z=4 Moster+13 10 5 z=2 Behroozi+13 z=4 Behroozi+13 10 4 0 . 0 10 9 10 10 10 11 10 12 10 9 10 10 10 11 10 12 0 . 0 0 . 2 0 . 4 0 . 6 0 . 8 1 . 0 M [M ] Halo Mass [M ⊙ ]

Data from NIHAO XII - Dutton et al. 2017 ALFALFA (Huang et al. 2012) log (Neutral Gas) log (Stellar Mass)

Data from NIHAO XII - Dutton et al. 2017 ALFALFA (Huang et al. 2012) log (Neutral Gas) log (Stellar Mass)

NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 2 log (HI Size / [kpc] ) log (R HI / kpc) 1 횺 (R HI )= 1 M ⊙ /pc 2 0 NIHAO Swaters 1999 − 1 Swaters 1999 12 6 7 8 9 10 11 log (M HI / M � ) log (HI Mass)

NIHAO VIII: CGM NIHAO XIII: Clumps Thales Gutcke Tobias Buck (see Poster) (Talk tomorrow) U-band Gas 0 . 001 L ∗ <L < 0 . 1 L ∗ 10kpc <b < 100kpc 16 15 14 13 log 10 1 HI [cP − 1 ] 300.0 0 . 1 L ∗ <L <L ∗ 100kpc <b < 100kpc 16 15 SFR rgb 14 13 300.0 L ∗ <L < 7 L ∗ 100kpc <b < 300kpc 16 15 14 13 −3.0 −2.5 −2.0 −1.5 −1.0 −0.5 0.0 0.5 1.0 50 100 100 log /// ∗ IPpact 3araPeter [Npc] NIHAO LCDM simulations form reasonable galaxies

Mock HI linewidth los Velocity 145 147 Average Maximum HI Flux Flux 50% W 50 HI Flux 0 − 200 − 100 0 100 200 los Velocity [km/s]

Maximum Circular Velocity of DMO simulation

HI linewidths vs V max of dark matter only NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 g5.02e11 145 2 . 5 168 log 10 (0.5 W 50 ) [km s -1 ] W MAX 50 2 . 0 V 50 / km s − 1 � 145 1 . 5 147 W MEDIAN � 50 log 1 . 0 100 projections 145 0 . 5 per galaxy 46 W MIN 50 1 . 5 2 . 0 2 . 5 � V DM max / km s − 1 � log log 10 (V max DMO ) [km s -1 ] 0 − 200 − 100 0 100 200

C old D ark M atter fails on small scales NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 2 . 5 log 10 (0.5 W 50 ) [km s -1 ] Klypin was right 0.5W 50 =V maxDMO 2 . 0 V 50 / km s − 1 � 1 . 5 � log 1 . 0 100 projections 0 . 5 per galaxy 1 . 5 2 . 0 2 . 5 � V DM max / km s − 1 � log log 10 (V max DMO ) [km s -1 ]

HI linewidths vs V max of dark matter only NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 2 . 5 log 10 (0.5 W 50 ) [km s -1 ] Klypin was right 0.5W 50 =V maxDMO 2 . 0 V 50 / km s − 1 � CDM is in trouble? 1 . 5 � log 1 . 0 100 projections 0 . 5 per galaxy 1 . 5 2 . 0 2 . 5 � V DM max / km s − 1 � log log 10 (V max DMO ) [km s -1 ]

HI linewidths vs V max of dark matter only NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 2 . 5 log 10 (0.5 W 50 ) [km s -1 ] Klypin was right 0.5W 50 =V maxDMO 2 . 0 V 50 / km s − 1 � CDM is in trouble? 1 . 5 � log 1 . 0 100 projections 0 . 5 per galaxy 1 . 5 2 . 0 2 . 5 � V DM max / km s − 1 � log log 10 (V max DMO ) [km s -1 ]

C old D ark M atter works on small scales NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 2 dN/dlogV [h 3 Mpc -3 ] 1 dN / dlog(V 50 ) / h 3 Mpc − 3 � 0 − 1 � log − 2 NIHAO Klypin et al. 2015 Klypin et al. 2015 uncorrected LCDM Klypin et al. 2015 1 . 0 1 . 2 1 . 4 1 . 6 1 . 8 2 . 0 2 . 2 2 . 4 2 . 6 � V 50 / km s − 1 � log log 10 (0.5 W 50 ) [km s -1 ]

C old D ark M atter works on small scales NIHAO X - Macciò, Udrescu, Dutton, et al. 2016 2 dN/dlogV [h 3 Mpc -3 ] 1 dN / dlog(V 50 ) / h 3 Mpc − 3 � 0 − 1 � log − 2 NIHAO Klypin et al. 2015 Klypin et al. 2015 uncorrected LCDM Klypin et al. 2015 1 . 0 1 . 2 1 . 4 1 . 6 1 . 8 2 . 0 2 . 2 2 . 4 2 . 6 � V 50 / km s − 1 � log log 10 (0.5 W 50 ) [km s -1 ]

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

CDM is consistent with the HI Velocity Function • W 50 /2 ≈ V maxDMO for Milky Way mass galaxies • W 50 /2 ≪ V maxDMO for dwarf galaxies 1. Mass loss (~15%) 2. HI extent (~20%) 3. Non-circular motions (~30%) } most dwarfs are NOT 4. Projection (~30%) thin rotating disks

R adial A cceleration R elation McGaugh et al. 2016 NIHAO simulations Observed Acceleration (V 2 /r) [m/s] Acceleration due to baryons Dutton et al. in prep (V 2bar /r) [m/s]

HI velocity profile shape depends on mass � 1 . 0 0 . 9 0 . 8 W 50 /W 20 0 . 7 0 . 6 0 . 5 NIHAO 0 . 4 Bradford et al. 2016 W 50 / W 20 = 0 . 656 W 20 = W 50 + 25 0 . 3 0 . 4 0 . 8 1 . 2 1 . 6 2 . 0 2 . 4 2 . 8 log(V 20 / km s − 1 ) NIHAO X - Macciò et al. 2016