Satellites in MW-Mass Halos theory Single LSST: 93-179 sats DES: - - PowerPoint PPT Presentation

▶
satellites in mw mass halos
SMART_READER_LITE
LIVE PREVIEW

Satellites in MW-Mass Halos theory Single LSST: 93-179 sats DES: - - PowerPoint PPT Presentation

Mar 14, 2023 392 likes •678 views

Satellites of satellites: LCDM predictions for the satellite population of M33 Credit: NASA, ESA, and M. Durbin, J. Dalcanton, and B. F. Williams (University of Washington) Ekta Patel 1,2 , Jeff Carlin 3 , Erik Tollerud 4 , Michelle Collins 5 ,

slide-1
SLIDE 1

Satellites of satellites:

LCDM predictions for the satellite population of M33

Ekta Patel1,2, Jeff Carlin3, Erik Tollerud4, Michelle Collins5, Greg Dooley6

Credit: NASA, ESA, and M. Durbin, J. Dalcanton, and B. F. Williams (University of Washington)

1 U. Arizona, 2 UC Berkeley - Miller Institute, 3 LSST, 4 STScI, 5 U. Surrey, 6 Google

slide-2
SLIDE 2

Ekta Patel U. Arizona/Berkeley

Satellites in MW-Mass Halos

Single LSST: 93-179 sats DES: 19-37 sats

Tollerud+08; see also Newton+18

theory

slide-3
SLIDE 3

Crnojević+19; see also Bennet+19

Ekta Patel U. Arizona/Berkeley

Satellites in MW-Mass Halos

Single LSST: 93-179 sats DES: 19-37 sats

Tollerud+08; see also Newton+18

theory

  • bservations
slide-4
SLIDE 4

Ekta Patel U. Arizona/Berkeley

Satellites in MW-Mass Halos

SAGA; Geha+17

100 MW-mass analogs at completion! Single LSST: 93-179 sats DES: 19-37 sats

Tollerud+08; see also Newton+18

theory

  • bservations
slide-5
SLIDE 5

Satellites in 1011 M⦿ Halos

Dooley+17b

(see also D’Onghia & Lake 08, Sales+13, Li & Helmi 2008)

Sales+13: 1 SMC, 5-40 ultra- faint dwarf galaxies (UFDs): M ∼ (0.1–1) × 104 M⦿ Dooley+17b: 2-12 UFDs with M > 104 M⦿

Ekta Patel U. Arizona/Berkeley

It becomes increasingly difficult to search for satellites around sub-MW mass haloes (< 1011 M⦿) as many satellites are in the ultra-faint regime. The LMC(+SMC) is the nearest example to test predictions.

See also Jethwa+16, Kallivayalil+18 (and reference within)

slide-6
SLIDE 6

Satellites in 1011 M⦿ Halos

Dooley+17b

(see also D’Onghia & Lake 08, Sales+13, Li & Helmi 2008)

Sales+13: 1 SMC, 5-40 ultra- faint dwarf galaxies (UFDs): M ∼ (0.1–1) × 104 M⦿ Dooley+17b: 2-12 UFDs with M > 104 M⦿

Ekta Patel U. Arizona/Berkeley

It becomes increasingly difficult to search for satellites around sub-MW mass haloes (< 1011 M⦿) as many satellites are in the ultra-faint regime. The LMC(+SMC) is the nearest example to test predictions.

See also Jethwa+16, Kallivayalil+18 (and reference within) Credit: V. Belokurov, S. Koposov (IoA, Cambridge). Photo: Y. Beletsky (Carnegie Observatories)

slide-7
SLIDE 7

M33: M31’s Most Massive Satellite Galaxy

Ekta Patel U. Arizona/Berkeley

slide-8
SLIDE 8

M33: M31’s Most Massive Satellite Galaxy

  • M = 3.2 x 109 M⦿ → Mhalo~1011 M⦿
  • isolated LMC counterpart
  • 200 kpc from M31
  • ~10% of M31’s mass
  • morphology shows hints of previous

interaction(s) in gas and stars: M31

  • r satellite companions?

Ekta Patel U. Arizona/Berkeley

slide-9
SLIDE 9

M33: M31’s Most Massive Satellite Galaxy

  • M = 3.2 x 109 M⦿ → Mhalo~1011 M⦿
  • isolated LMC counterpart
  • 200 kpc from M31
  • ~10% of M31’s mass
  • morphology shows hints of previous

interaction(s) in gas and stars: M31

  • r satellite companions?

Ekta Patel U. Arizona/Berkeley

slide-10
SLIDE 10

−200 200 400 kpc −1000 −800 −600 −400 −200 kpc

PREVIOUS: recent peri

tperi = 2.6 Gyr ago rperi = 55 kpc

Ekta Patel U. Arizona/Berkeley M31 M33

M33’s Conventional Orbital History:

Prior to 2012, M31’s proper motion (i.e. its tangential motion) was unknown. What orbital history best reproduces M33’s current morphology?

PAndAS; McConnachie+09

slide-11
SLIDE 11

−200 200 400 kpc −1000 −800 −600 −400 −200 kpc

PREVIOUS: recent peri

tperi = 2.6 Gyr ago rperi = 55 kpc

A New Orbital History for M33

Which orbital histories are allowed within the measured phase space?

  • 10,000 backwards

numerical integrations x 6 different mass models

Ekta Patel U. Arizona/Berkeley M31 M33

PAndAS; McConnachie+09

slide-12
SLIDE 12

−200 200 400 kpc −1000 −800 −600 −400 −200 kpc

PREVIOUS: recent peri

tperi = 2.6 Gyr ago rperi = 55 kpc

A New Orbital History for M33

Which orbital histories are allowed within the measured phase space? Gaia DR2 + HST + VLBA PMs (van der Marel+ w/ Patel, 2019)

HST + VLBA PMs (Patel+17a) tperi = ~6 Gyr ago rperi = ~100 kpc

  • 10,000 backwards

numerical integrations x 6 different mass models

  • < 1% of M33 orbits

reach Rperi = 55-100 kpc with tperi ≤ 3 Gyr

Ekta Patel U. Arizona/Berkeley M31 M33

PAndAS; McConnachie+09

slide-13
SLIDE 13

−200 200 400 kpc −1000 −800 −600 −400 −200 kpc

PREVIOUS: recent peri

tperi = 2.6 Gyr ago rperi = 55 kpc

A New Orbital History for M33

Which orbital histories are allowed within the measured phase space? Gaia DR2 + HST + VLBA PMs (van der Marel+ w/ Patel, 2019)

HST + VLBA PMs (Patel+17a)

NEW: first infall

tperi = ~6 Gyr ago rperi = ~100 kpc

  • 10,000 backwards

numerical integrations x 6 different mass models

  • < 1% of M33 orbits

reach Rperi = 55-100 kpc with tperi ≤ 3 Gyr

  • Gaia DR2 PMs further

support first infall

Ekta Patel U. Arizona/Berkeley M31 M33

PAndAS; McConnachie+09

slide-14
SLIDE 14

Applying techniques of Dooley+17a,b

Ekta Patel U. Arizona/Berkeley

Dark matter only Caterpillar suite: 33 MW-mass zooms (mp ~ 104 M⦿)

host galaxy

LCDM Predictions for M33’s Satellite Population

slide-15
SLIDE 15

Applying techniques of Dooley+17a,b

Ekta Patel U. Arizona/Berkeley

Dark matter only Caterpillar suite: 33 MW-mass zooms (mp ~ 104 M⦿)

  • 1. Determine the subhalo

mass function (SHMF) for host galaxies

host galaxy

LCDM Predictions for M33’s Satellite Population

slide-16
SLIDE 16

Applying techniques of Dooley+17a,b

Ekta Patel U. Arizona/Berkeley

Dark matter only Caterpillar suite: 33 MW-mass zooms (mp ~ 104 M⦿)

  • 1. Determine the subhalo

mass function (SHMF) for host galaxies

  • 2. Sample SHMF to generate

random realization of DM subhalos for host

host galaxy

LCDM Predictions for M33’s Satellite Population

slide-17
SLIDE 17

Applying techniques of Dooley+17a,b

Ekta Patel U. Arizona/Berkeley

Dark matter only Caterpillar suite: 33 MW-mass zooms (mp ~ 104 M⦿)

  • 1. Determine the subhalo

mass function (SHMF) for host galaxies

  • 2. Sample SHMF to generate

random realization of DM subhalos for host

  • 3. Model reionization by assigning

which subhalos remain dark

host galaxy

LCDM Predictions for M33’s Satellite Population

slide-18
SLIDE 18

Applying techniques of Dooley+17a,b

Ekta Patel U. Arizona/Berkeley

Dark matter only Caterpillar suite: 33 MW-mass zooms (mp ~ 104 M⦿)

  • 1. Determine the subhalo

mass function (SHMF) for host galaxies

  • 2. Sample SHMF to generate

random realization of DM subhalos for host

  • 3. Model reionization by assigning

which subhalos remain dark

  • 4. Assign stellar masses

via M - Mhalo relation (Garrison-Kimmel+17)

host galaxy

LCDM Predictions for M33’s Satellite Population

slide-19
SLIDE 19

Applying techniques of Dooley+17a,b

Ekta Patel U. Arizona/Berkeley

Dark matter only Caterpillar suite: 33 MW-mass zooms (mp ~ 104 M⦿)

  • 1. Determine the subhalo

mass function (SHMF) for host galaxies

  • 2. Sample SHMF to generate

random realization of DM subhalos for host

  • 3. Model reionization by assigning

which subhalos remain dark

  • 4. Assign stellar masses

via M - Mhalo relation (Garrison-Kimmel+17)

host galaxy

LCDM Predictions for M33’s Satellite Population

M33 properties: Rvir = 161 kpc Mvir = 2.5⨉ 1011 M⦿

slide-20
SLIDE 20

LCDM Predictions for M33’s Satellite Population*

Ekta Patel U. Arizona/Berkeley

PAndAS observed ~40%

  • f M33’s virial volume and
  • ne candidate satellite

was identified (MV ~ -6.5). PAndAS

50 100 161 50 kpc 150 kpc 100 kpc

*corrected for geometric effects

slide-21
SLIDE 21

(Patel+18b)

LCDM Predictions for M33’s Satellite Population*

Ekta Patel U. Arizona/Berkeley

PAndAS observed ~40%

  • f M33’s virial volume and
  • ne candidate satellite

was identified (MV ~ -6.5). PAndAS

50 100 161 50 kpc 150 kpc 100 kpc

*corrected for geometric effects

8±4 satellites at M ≥ 104 M⦿

slide-22
SLIDE 22

Ekta Patel U. Arizona/Berkeley

Predictions for Surviving M33 Satellites

If M33 really is on first infall (as suggested by Gaia and HST) all of the satellites that fell into M31’s halo with M33 should survive until today.

slide-23
SLIDE 23

van den Bosch+18

Ekta Patel U. Arizona/Berkeley

Predictions for Surviving M33 Satellites

If M33 really is on first infall (as suggested by Gaia and HST) all of the satellites that fell into M31’s halo with M33 should survive until today.

slide-24
SLIDE 24

van den Bosch+18

Ekta Patel U. Arizona/Berkeley

Predictions for Surviving M33 Satellites

If M33 really is on first infall (as suggested by Gaia and HST) all of the satellites that fell into M31’s halo with M33 should survive until today.

Rperi Rtidal

# surviving satellites (M ≥ 104 M⦿) 100 kpc 49-53 kpc 4±3 150 kpc 68-73 kpc 6±3

slide-25
SLIDE 25

−5 5 10 15 20 25 30 35

RA [deg]

20 25 30 35 40 45 50

Dec [deg]

AND XXII

PAndAS

50 kpc 100 kpc 161 kpc And XXII

Ekta Patel U. Arizona/Berkeley

Hunting for Satellites of M33

To reach g~27 and i~26.3 (HSC-SSP Deep): 11 fields/2 nights on HSC 50 fields/8.5 nights on HSC

  • E. Patel, R. Beaton, J. Carlin, K. McQuinn, M. Collins, E.

Tollerud, A. Price-Whelan, R. Guhathakurta, K. Gilbert,

  • M. Chiba, M. Tanaka

M31

M33

100 kpc 161 kpc

slide-26
SLIDE 26

−5 5 10 15 20 25 30 35

RA [deg]

20 25 30 35 40 45 50

Dec [deg]

AND XXII

PAndAS

50 kpc 100 kpc 161 kpc And XXII

Ekta Patel U. Arizona/Berkeley

Hunting for Satellites of M33

To reach g~27 and i~26.3 (HSC-SSP Deep): 11 fields/2 nights on HSC 50 fields/8.5 nights on HSC

WFIRST could

  • bserve all 50 fields

in ~4 hours!

  • E. Patel, R. Beaton, J. Carlin, K. McQuinn, M. Collins, E.

Tollerud, A. Price-Whelan, R. Guhathakurta, K. Gilbert,

  • M. Chiba, M. Tanaka

M31

M33

100 kpc 161 kpc

slide-27
SLIDE 27
  • M33 is expected to host 8±4 satellites at M ≥ 104 M⦿ (90%

within 100 kpc survey) if it’s on first infall and fewer if it had a recent interaction with M31.

  • A census of M33’s satellite population will help constrain its
  • rbital history and provide a direct test for small-scale LCDM

predictions.

  • Deep observations of M33’s halo will additionally characterize

the stellar “warps” in M33’s outer disk, help determine if it has a stellar halo, provide an improved distance to And XXII, and reveal remnant stellar streams.

Summary

ektapatel@email.arizona.edu

See Patel et al. 2018b, MNRAS, 480, 1883