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Cosmic Controversies

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Cosmic Controversies Milky Way Satellites: Probes of Dark Matter Microphysics Ethan Nadler 10/7/19 Small Halos as DM Probes CDM WDM Lovell et al. 2011 Faint Galaxies as DM Probes CDM WDM Milky Way Satellites Classical Boo III CVn II Com SDSS CVn I Boo I Boo II +60◦ Leo II PS1 Vir I Wil 1 Leo V Boo IV Leo IV Seg 1 DES UMa I Leo I UMi Dra II Crt II Sex DECam Her +30◦ UMa II Dra HSC Hyd II ATLAS Gaia Ant II 0◦ Sgr Car III Car II Tri II Sgr II Car LMC Pic II Col I 30 Hyi I ◦ Pic I − Seg 2 Peg III SMC Psc II Ret III Ret II Tuc II Tuc V Gru II Hor I Aqr II Tuc IV Gru I Cet III Tuc III Hor II 60◦ Phe II − For Cet II Scl Drlica-Wagner et al. in prep. 1. Resimulate Milky Way- like halos from large cosmological volume. ↵<latexit sha1_base64="+wSBPeL8nxBdvzPXA2qswhGhfpg=">AAAB7XicbVBNS8NAEJ3Ur1q/qh69LBbBU0mqoMeiF48V7Ae0oUy2m3btZhN2N0IJ/Q9ePCji1f/jzX/jts1BWx8MPN6bYWZekAiujet+O4W19Y3NreJ2aWd3b/+gfHjU0nGqKGvSWMSqE6BmgkvWNNwI1kkUwygQrB2Mb2d++4kpzWP5YCYJ8yMcSh5yisZKrR6KZIT9csWtunOQVeLlpAI5Gv3yV28Q0zRi0lCBWnc9NzF+hspwKti01Es1S5COcci6lkqMmPaz+bVTcmaVAQljZUsaMld/T2QYaT2JAtsZoRnpZW8m/ud1UxNe+xmXSWqYpItFYSqIicnsdTLgilEjJpYgVdzeSugIFVJjAyrZELzll1dJq1b1Lqq1+8tK/SaPowgncArn4MEV1OEOGtAECo/wDK/w5sTOi/PufCxaC04+cwx/4Hz+AIzPjxw=</latexit> 2. Paint satellite galaxies σ <latexit sha1_base64="P99ez1bWyq6CFJ3tVJiBTJPQvlE=">AAAB/HicbVBNS8NAEN3Ur1q/oj16CRbBU0mqoMeiF48V7Ae0IWy2m3TpbhJ2J2II8a948aCIV3+IN/+N2zYHbX0w8Hhvhpl5fsKZAtv+Nipr6xubW9Xt2s7u3v6BeXjUU3EqCe2SmMdy4GNFOYtoFxhwOkgkxcLntO9Pb2Z+/4FKxeLoHrKEugKHEQsYwaAlz6yPFAsF9vIR0EfIQ8yLwjMbdtOew1olTkkaqETHM79G45ikgkZAOFZq6NgJuDmWwAinRW2UKppgMsUhHWoaYUGVm8+PL6xTrYytIJa6IrDm6u+JHAulMuHrToFhopa9mfifN0whuHJzFiUp0IgsFgUptyC2ZklYYyYpAZ5pgolk+laLTLDEBHReNR2Cs/zyKum1ms55s3V30Whfl3FU0TE6QWfIQZeojW5RB3URQRl6Rq/ozXgyXox342PRWjHKmTr6A+PzB8RalX4=</latexit> gal onto subhalos using B<latexit sha1_base64="rCx6YZKyFarkehd6/kmCVau7Ixc=">AAAB8nicbVDLSgMxFM3UV62vqks3wSK4KjNV0GWpG5cV7AOmQ8mkmTY0kwzJHaEM/Qw3LhRx69e482/MtLPQ1gOBwzn3knNPmAhuwHW/ndLG5tb2Tnm3srd/cHhUPT7pGpVqyjpUCaX7ITFMcMk6wEGwfqIZiUPBeuH0Lvd7T0wbruQjzBIWxGQsecQpASv5g5jAhBKRtebDas2tuwvgdeIVpIYKtIfVr8FI0TRmEqggxviem0CQEQ2cCjavDFLDEkKnZMx8SyWJmQmyReQ5vrDKCEdK2ycBL9TfGxmJjZnFoZ3MI5pVLxf/8/wUotsg4zJJgUm6/ChKBQaF8/vxiGtGQcwsIVRzmxXTCdGEgm2pYkvwVk9eJ91G3buqNx6ua81WUUcZnaFzdIk8dIOa6B61UQdRpNAzekVvDjgvzrvzsRwtOcXOKfoD5/MHcyGRXA==</latexit> <latexit sha1_base64="gV1REod6INZYF0m2I1PcPtZcxYU=">AAAB+XicbVDLSsNAFL2pr1pfUZduBovgqiRV0WXRjRuhgn1AG8JkOm2HTiZhZlIoIX/ixoUibv0Td/6NkzYLbT0wcDjnXu6ZE8ScKe0431ZpbX1jc6u8XdnZ3ds/sA+P2ipKJKEtEvFIdgOsKGeCtjTTnHZjSXEYcNoJJne535lSqVgknvQspl6IR4INGcHaSL5t90OsxwTz9CHz0ysn8+2qU3PmQKvELUgVCjR9+6s/iEgSUqEJx0r1XCfWXoqlZoTTrNJPFI0xmeAR7RkqcEiVl86TZ+jMKAM0jKR5QqO5+nsjxaFSszAwk3lOtezl4n9eL9HDGy9lIk40FWRxaJhwpCOU14AGTFKi+cwQTCQzWREZY4mJNmVVTAnu8pdXSbtecy9q9cfLauO2qKMMJ3AK5+DCNTTgHprQAgJTeIZXeLNS68V6tz4WoyWr2DmGP7A+fwBvspOG</latexit> 50 galaxy—halo model. M σ<latexit sha1_base64="w6kf9ugSeuomJ3tKQ5nBZFNm7MY=">AAAB73icbVDLSgNBEOz1GeMr6tHLYBA8hd0o6DHoxYsQwTwgWcLsZDYZMo91ZlYIS37CiwdFvPo73vwbJ8keNLGgoajqprsrSjgz1ve/vZXVtfWNzcJWcXtnd2+/dHDYNCrVhDaI4kq3I2woZ5I2LLOcthNNsYg4bUWjm6nfeqLaMCUf7DihocADyWJGsHVSu2vYQODeXa9U9iv+DGiZBDkpQ456r/TV7SuSCiot4diYTuAnNsywtoxwOil2U0MTTEZ4QDuOSiyoCbPZvRN06pQ+ipV2JS2aqb8nMiyMGYvIdQpsh2bRm4r/eZ3UxldhxmSSWirJfFGccmQVmj6P+kxTYvnYEUw0c7ciMsQaE+siKroQgsWXl0mzWgnOK9X7i3LtOo+jAMdwAmcQwCXU4Bbq0AACHJ7hFd68R+/Fe/c+5q0rXj5zBH/gff4A8YOP5w==</latexit> M 3. Apply observational selection functions based on imaging data. Markov Chain Monte Carlo 4. Calculate likelihood of observed satellites given galaxy—halo connection parameters. Nadler et al. in prep. Galaxy-Halo Connection Model EN, Y.-Y. Mao, G. Green, R. Wechsler 2019 Observational Selection Functions 1.0 3 DES Boo III Tuc II Tuc IV 2 UMa II Gru II 0.8 Tuc III Ret II Com Seg 2 (r / pc) Boo II Dra IISeg 1 Cet II 10 Wil 1 Tuc V Tri II log 1 0.6 8 <D<16 kpc 16 <D<32 kpc 32 <D<64 kpc ciency ffi 0 3 Crt II Preliminary Sex CVn I UMi Boo IV 0.4 Dra UMa I Leo II Ind II Eri II Her Boo I Col I Detection E Aqr II 2 Ret III Leo IV Peg III Cet III Sgr II Hor I Hor II Vir I CVn II Psc II (r / pc) Phe II Leo V 10 0.2 Gru I Pic I log 1 64 <D<128 kpc 128 <D<256 kpc 256 <D<512 kpc 0 0.0 10.0 7.5 5.0 2.5 0.0 10.0 7.5 5.0 2.5 0.0 10.0 7.5 5.0 2.5 0.0 − − − − − − − − − − − − MV MV MV Drlica-Wagner et al. in prep. Mock Satellite Observations simulated “LMC” Mock Satellite Observations simulated “LMC” Mock Satellite Observations simulated “LMC” Minimum Halo Mass Constraints +0.016 ↵ = 1.436 0.019 − − +0.057 σM =0.201 0.000 0.5 − 0.4 M σ 0.3 +0.43 50 =7.51 0.00 M − 8.5 50 M 8.0 +0.36 =0.70 0.22 B − 1.6 B 0.8 Preliminary +0.00 σgal =1.00 0.62 − 0.8 gal σ 0.4 +9.4 = 32.6 8.3 75 A − 50 A 25 +0.15 σR =0.26 0.16 − 0.6 R σ 0.3 +0.30 n =1.47 0.50 − 1.6 n 0.8 1.501.451.40 0.3 0.4 0.5 8.0 8.5 0.8 1.6 0.4 0.8 25 50 75 0.3 0.6 0.8 1.6 − − − ↵ σM 50 σgal σR n M B A Nadler et al. in prep. Minimum Halo Mass Constraints +0.016 ↵ = 1.436 0.019 − − Classical+SDSS+DES +0.057 Classical+SDSS σM =0.201 0.000 0.5 − 0.4 M σ 0.3 +0.43 50 =7.51 0.00 M − 8.5 1.8 50 M 8.0 +0.36 =0.70 0.22 M 1.2 B − σ 1.6 B 0.6 0.8 Preliminary +0.00 σgal =1.00 0.62 − 0.8 gal 8.5 σ 0.4 +9.4 min = 32.6 8.3 75 A − M 8.0 50 A 25 +0.15 σR =0.26 0.16 − 1.8 0.6 R σ 0.3 1.2 +0.30 B n =1.47 0.50 − 1.6 0.6 n 0.8 1.501.451.40 0.3 0.4 0.5 8.0 8.5 0.8 1.6 0.4 0.8 25 50 75 0.3 0.6 0.8 1.6 1.44 1.36 1.28 0.6 1.2 1.8 8.0 8.5 0.6 1.2 1.8 − − − − − − ↵ σM 50 σgal σR n ↵ σM min M B A M B Theoretical Uncertainties Subhalo Number Counts Fit to Satellites 2 109 ] ⇥ M [ 109 50 M 5 108 ⇥ 2 108 ⇥ Upper Limit on 108 Minimal + MW Host + Subhalo + Satellites + Satellites CDM Mass Disruption (Confirmed) (Unconfirmed) Nadler et al. in prep. DM-Baryon Scattering Constraints • Early-time DM-baryon scattering M [M ] suppresses small-scale power 1016 1014 1012 1010 108 1.0 • Mass of the smallest halo allowed to form corresponds to the size of the horizon when 0.75 CDM /P 0.5 mWDM =0.3 keV mWDM =1.2 keV m =4.7 keV collisional WDM • Smallest detected subhalo yields P 27 2 0.25 σ0 = 10− cm 28 2 (analytic!) cross section limit: σ0 = 10− cm 29 2 σ0 = 10− cm 0.05 0.1 1 5 10 30 50 1 k [h Mpc− ] EN, V. Gluscevic, K. Boddy, R. Wechsler 2019 DM-Baryon Scattering Constraints 24 10− CMB Lyman-↵ XQC ] 26 XQC ] 26 2 10 2 10− MiniBoone CR [cm [cm 0 0 28 σ 28 σ 10− XENON1T CR 30 10− Direct Detection cross section cross section 32 10− 34 10−34 10− 5 4 3 2 1 0 1 2 10− 10− 10− 10− 10− 10 10 10 dark matter mass mχ [GeV] EN, V. Gluscevic, K. Boddy, R. Wechsler 2019 DM-Baryon Scattering Constraints 24 10− CMB Lyman-↵ XQC ] 26 2 10− MiniBoone CR [cm 0 28 σ 10− XENON1T CR 30 10− Direct Detection cross section 32 10− 34 10− 5 4 3 2 1 0 1 2 10− 10− 10− 10− 10− 10 10 10 dark matter mass mχ [GeV] EN, V. Gluscevic, K. Boddy, R. Wechsler 2019 DM-Baryon Scattering Constraints 24 10− CMB Lyman-↵ XQC ] 26 2 10− MiniBoone CR [cm 0 28 Milky Way Satellites σ 10− XENON1T CR 30 10− Direct Detection cross section 32 10− Analytic Estimate Population Analysis 34 10− 5 4 3 2 1 0 1 2 10− 10− 10− 10− 10− 10 10 10 dark matter mass mχ [GeV] EN, V. Gluscevic, K. Boddy, R. Wechsler 2019 Warm DM Constraints • Minimum detected halo mass 24 10− mχ = 10 GeV constrains thermal relic WDM: 1 mχ = 10− GeV 25 3 10− mχ = 10− GeV ] 2 5 M 0.3 mχ = 10− GeV hm − [cm 26 10− mWDM =2.3 keV 0 109 M σ <latexit sha1_base64="bfpkQqx8y7tCSoLpEbTcEWOFBNU=">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</latexit> 27 ⇣ ⌘ 10− 28 • Mapping between WDM and 10− DM-baryon scattering constrains cross section 10 29 any “thermal” DM model: − 30 10− 0 2 4 6 8 10 T (σ ,m ) m mWDM [keV] dec 1 χ = WDM,1 T (σ ,m ) m <latexit sha1_base64="l49tPnaQxw1QjcWFVTZInKsn8Rk=">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</latexit> dec 2 χ WDM,2 m > 4 keV (95% C.L.) <latexit sha1_base64="hEb4Ld7jcER7dSKxzakrkHVB0eI=">AAACFnicbVDLSgMxFM34rPVVdekmWAp14TBTK+pGinXhQqGCfUBnKJk0bUOTmSHJCGWYr3Djr7hxoYhbceffmLaz0NYDF07OuZfce7yQUaks69tYWFxaXlnNrGXXNza3tnM7uw0ZRAKTOg5YIFoekoRRn9QVVYy0QkEQ9xhpesPq2G8+ECFp4N+rUUhcjvo+7VGMlJY6uSPeiR3B4+bVbZLAC1h24Pg5JI3EgcXzE6cwFarmjZkcdnJ5y7QmgPPETkkepKh1cl9ON8ARJ77CDEnZtq1QuTESimJGkqwTSRIiPER90tbUR5xIN56clcCCVrqwFwhdvoIT9fdEjLiUI+7pTo7UQM56Y/E/rx2p3pkbUz+MFPHx9KNexKAK4Dgj2KWCYMVGmiAsqN4V4gESCCudZFaHYM+ePE8aJdM+Nkt35XzlMo0jA/bBASgCG5yCCrgGNVAHGDyCZ/AK3own48V4Nz6mrQtGOrMH/sD4/AG5Gp0t</latexit> WDM DM Formation Redshift Constraints • Excess radiation decaying to DM after BBN (late-forming DM) suppresses small-scale power • Half-mode scale is related to size of horizon when DM forms: k 1.4 k <latexit sha1_base64="WUXC2YY1wzfWoFnZkSFNB9wm1mM=">AAACBXicbVDLSsNAFJ3UV62vqEtdDBbBVUhqQZdFNy4r2Ac0IUymk3bITBJmJmIJ2bjxV9y4UMSt/+DOv3HaZqGtBy4czrmXe+8JUkalsu1vo7Kyura+Ud2sbW3v7O6Z+wddmWQCkw5OWCL6AZKE0Zh0FFWM9FNBEA8Y6QXR9dTv3RMhaRLfqUlKPI5GMQ0pRkpLvnkc+bkreD7mRQFdlKYieYCO1XRh5Ie+Wbctewa4TJyS1EGJtm9+ucMEZ5zECjMk5cCxU+XlSCiKGSlqbiZJinCERmSgaYw4kV4++6KAp1oZwjARumIFZ+rviRxxKSc80J0cqbFc9Kbif94gU+Gll9M4zRSJ8XxRmDGoEjiNBA6pIFixiSYIC6pvhXiMBMJKB1fTITiLLy+TbsNyzq3GbbPeuirjqIIjcALOgAMuQAvcgDboAAwewTN4BW/Gk/FivBsf89aKUc4cgj8wPn8Ar36YBg==</latexit>
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