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Massive Clusters in the Milky Way Ignacio Negueruela Gainesville, April 2016

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Massive Clusters in the Milky Way Ignacio Negueruela Gainesville, April 2016 RSGC crowd Ricardo Dorda, Amparo Marco Universidad de Alicante , Spain Carlos González-Fernández CASU, Cambridge, UK Wd1 crowd J. Simon Clark, Ben W. Ritchie Open University , UK Paul A. Crowther, Simon Goodwin Shefeld , UK Francisco Najarro CAB–CSIC, Spain Massive clusters in the Milky Way Ignacio Negueruela Gainesville, April 2016 What are we calling a young massive cluster? Definition of “massive” depends on context In the Milky Way, ( Focuswe go Meeting for initial at mass the Beijing ! Mcl ≥ 10 M" IAU GA, 2013 ) #n astrophysical la$oratory on its ownFiger - cf. 2005 'pperCrowther+ limit to the 2010 stellar mass (#rches, ) *1+,, ; talk by -a$allero-.ieves/ VdBH 222 7+ d -epheid *56s 8l'e giants Age ~18 Ma Distance 6 kpc 4 Mass ~2x10 M⊙ V #vLSR≈= 1&2-100±3 km/s ℓ = Marco et al. 2014; A&A 567, A73 +!34 Distribution of young massive clusters in the Milky Way Cygnus Mercer 81 Center Arches Quintuplet Mercer 30 Norma RSG1 Stephenson2Scutum RSGC3 Alicante 10 Crux Alicante 7 Westerlund 1 NGC 3603 Sagitarius Carina Masgomas-1 Tr14+16 Westerlund 2 Orion Perseus Young massive clusters º Even if these (LMC) clusters are not quite as spectacular as those found in genuine starburst galaxies, they are still more massive than any of the open clusters seen in the Milky Way todayº Larsen & Richtler 1999, A&A 345, 59 Spiral starburst galaxy NGC 3310 The young globular NGC 1850, in the LMC The young globular NGC 1755, in the LMC !ST image #rom $ikipe&ia' M 11 The interme&iate- age cluster M11, in the Mil%y $ay *SO,$-.' M 11 McNamara & Sanders (1977) A&A 54, 569 5tar counts: 23 M" :irial9 6 M" Bruch & Sanders (1983) A&A 121, 237 e.g. N6- 6,+: 80 M" Battinelli & Capuzzo-Dolcetta5ee also (1991, MNRAS 249, 76) The young cluster NGC 663, in the Mil%y $ay Michael Siniscalchi @ helixgate1net) Bruch & Sanders (1983) A&A 121, 237 e.g. N6- 6,+: 80 M" < moreMarco like et el.,! in prep.M" The young cluster NGC 663, in the Mil%y $ay Michael Siniscalchi @ helixgate1net) Distribution of young massive clusters in the Milky Way Cygnus Mercer 81 Center Arches Quintuplet Mercer 30 Norma RSG1 Stephenson2Scutum RSGC3 Alicante 10 Crux Alicante 7 Westerlund 1 NGC 3603 Sagitarius Carina Masgomas-1 Tr14+16 Westerlund 2 Orion Perseus NGC 653 NGC 663, the )ore of Cas+B8 90’ = 65 pc @ 2.5 kpc NGC 654 Alicante 9 – cluster candidate Negueruela et al. (2011) Alicante 7 – cluster RSGC3 – big cluster Negueruela et al. (2011) Clark et al. (2009) 30’ = 52 pc @ 6 kpc 6limpse +, view towards l = 734, $ = 4 Alicante 10 – pretty big cluster González-Fernández & Negueruela (2012) Westerlund 1 is the most massive young open cluster so far known in the Milky Way. At least 150 evolved massive ( ) stars observed imply " M > 3 M 2 (Clark et al. 2005, A&A M 434,0 1 949M)" Star counts in the IR imply (Gennaro et ! al. 2011, M MNRAS ≥ 5x1 412, M "2469; talks by Lu & Andersen) 5Myr Age Ma d ~ 4 kpc ≈ 4 6.3 Myr V # ≈ 10 ,&3Myr with high rotation Gennaro et al. 2011, MNRAS 412, 2469 Negueruela et al. 2010, A&A, 516, A78 Old Geneva tracks Age Ma d ~ 6≿ kpc 5 V # ≈ 12 This is not isolated case! PMS tracks always give younger ages 5Myr 6.3 Myr Naylor 2009, MNRAS 399, 432 ,&3Myr with high rotation Bell et al. 2012, MNRAS 424, 3178 Negueruela et al. 2010, A&A, 516, A78 Old Geneva tracks Age Ma d ~ 6≿ kpc 5 V # ≈ 12 This is a 9.2-d (almost- detached) eclipsing binary Wd1-13 (Bonanos 2007, AJ 133, 2696) Dynamical determination Evidence for two separate indicates both members had evolutionary channels for massive initial , li!ely " stars ( ): (RitchieM et@ >al. 3 2010, M" A&A 520, A48M") Single A! O →MBSGB →YHG→RSG→WR #nother member with " Binary O→BHG/LBV→WR (Koumpia & Bonanos 2012, A&A 547, A30) M@ 0 M" FLAMES spe!"roscopi! sur%ey ≥ 40% of observed stars are binaries. Most (all?) WR stars are binaries. W43a (B0 Ia ) Porb = 16.3 days Ritchie et al. 2009, A&A 507, 1597 Ritchie et al. 2011, BSRSL 80, 628 Clark et al. 2011, A&A 531, A28 W239 (WC9d) Porb = 5.1 days A real vel#!i"y dispersi#n No evidence for dynamically separate subclusters Radial vel#ci"ies f#r Wd1 members, c#rrected f#r (inari"y and $lsa"i#n vsys= -42.9±4.6 km/s (Clark et al., in preparation) $ield centred on Westerlund % (Negueruela et al., in preparation) Kothes & Dougherty (2007, A&A 468, 993) Westerlund 1 is completely isolated! S$''ary ! Chere is a significant population of massive (Mcl >10 M") in the Milky Way& Cheir detection is mainly hindered $y high extinction& ! Stepheson 2, with M 0 5x10 M", is part of a h'ge str'cture& 2 Westerl'nd 1, containing 10 M ", formed monolythically, in a single b'rst& h & χ Per, the core of Per OB1 7oth Ritter8 A6+: 0401093' 50’ = 30 pc @ 2.1 kpc &tephenson 2 D4 > 25 )&*s (Davies et al. 2007, ApJ 671, 781; Negueruela et al. 2012, A&A 547, D2 A14) ! Implied mass 0 5x10 M" AV ≈ 11 Behind dust layer (LDN 515) Age 18-20 Myr D49 @ d = 6kpc D1 Stephenson 1990 (AJ 99, 1867) Nakaya et al. 2001 (AJ 122, 876) Ortolani et al. 2002 (A&A 391, 179) 6DIME5F 3%colour image &tephenson 2 > 25 )&*s (Davies et al. 2007, ApJ 671, 781; Negueruela et al. 2012, A&A 547, A14) Clark et al. 2014, A&A 561, A15 Westerlund 1 is completely isolated! Westerlund 1 is completely isolated! .
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