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NGC 147 Star Formation History and Stellar Wind Feedback in Two Low Metallicity Dwarf Galaxies: NGC 147 and NGC 185

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NGC 147 Star Formation History and Stellar Wind Feedback in Two Low Metallicity Dwarf Galaxies: NGC 147 and NGC 185 NGC 185 NGC 147 Star Formation History and Stellar Wind Feedback in Two Low Metallicity Dwarf Galaxies: NGC 147 and NGC 185 Roya Hamedani Golshan Dr. Atefeh Javadi Dr. Jacco Th. van Loon Dr. Habib Khosroshahi Galaxies of Many Colours: Star Formation Across 2 Wednesday, June 03, 2015 Cosmic Time Outline: AGB stars NGC 147 and NGC 185; Observational Data Star Formation History Feedback from Dusty Stellar Wind Galaxies of Many Colours: Star Formation Across 3 Wednesday, June 03, 2015 Cosmic Time AGB stars o Mass : 0.8 – 8 �⊙ o Luminosity : 1000 – 6000 �⊙ o Effective temperature : 3000 – 4500 K o Maximum luminosity : 1 – 2.5 µm Luminosity o Age : 30 million to 10 billion yr o Long period variables : 100 – 1000 days Surface Temperature ( Spectral Class ) o Mass Loss : 10 �⊙�� Galaxies of Many Colours: Star Formation Across 7 Wednesday, June 03, 2015 Cosmic Time Target galaxies �������=0.0015 �������= 0.0019 630 Kpc 780 Kpc http://pixgood.com/local-group-diagram.html Galaxies of Many Colours: Star Formation Across 10 Wednesday, June 03, 2015 Cosmic Time Observational Data NGC 147 Near Infrared Data 1.27 Kpc I. LPV II.Cstars Kpc Mid Infrared Data 1.27 I. Spitzer Galaxies of Many Colours: Star Formation Across 11 Wednesday, June 03, 2015 Cosmic Time Observational Data NGC 185 Near Infrared Data 1.16 Kpc I. LPV II.Cstars Kpc Mid Infrared Data 1.16 I. Spitzer Galaxies of Many Colours: Star Formation Across 12 Wednesday, June 03, 2015 Cosmic Time Star Formation History Luminosity Mass Age Pulsation duration Star formation rate Galaxies of Many Colours: Star Formation Across 13 Wednesday, June 03, 2015 Cosmic Time Star Formation History �� = � � �� �� ∫ � � � �� �(�) = �� () ∫() � � �� Galaxies of Many Colours: Star Formation Across 14 Wednesday, June 03, 2015 Cosmic Time Using Padova model to drive SFH Galaxies of Many Colours: Star Formation Across 15 Wednesday, June 03, 2015 Cosmic Time Deriving initial mass & age Galaxies of Many Colours: Star Formation Across 16 Wednesday, June 03, 2015 Cosmic Time Pulsation duration Galaxies of Many Colours: Star Formation Across 17 Wednesday, June 03, 2015 Cosmic Time Star Formation History in NGC 147 7 Gyr 78% of total Mass � Total Mass Converted to Stars: �.� × �� ���� Galaxies of Many Colours: Star Formation Across 18 Wednesday, June 03, 2015 Cosmic Time Star Formation History in NGC 185 10 Gyr 61% of total Mass � Total Mass Converted to Stars: �.� × �� ���� Galaxies of Many Colours: Star Formation Across 20 Wednesday, June 03, 2015 Cosmic Time Feedback from Dusty Stellar Wind By Using DUSTY code Deriving the total injected dust into the ISM AGB Optical color depth Mass Loss Bolometric Luminosity correction � = ��� Galaxies of Many Colours: Star Formation Across 24 Wednesday, June 03, 2015 Cosmic Time Feedback from Dusty Stellar Wind Galaxies of Many Colours: Star Formation Across 25 Wednesday, June 03, 2015 Cosmic Time Feedback from Dusty Stellar Wind � = � + �� Javadi et al. (2013) Galaxies of Many Colours: Star Formation Across 26 Wednesday, June 03, 2015 Cosmic Time Feedback from Dusty Stellar Wind � � ��� = � + �� + �� + �� Javadi et al. (2013) Galaxies of Many Colours: Star Formation Across 27 Wednesday, June 03, 2015 Cosmic Time Feedback from Dusty Stellar Wind � ��/�⁄��/��̇ = �������� Javadi et al. (2013) Galaxies of Many Colours: Star Formation Across 28 Wednesday, June 03, 2015 Cosmic Time Results: � � • The total mass converted to stars is �. � × �� and �. � × �� ���� in NGC 147 and NGC 185 respectively. • Each galaxy shows one peak of star formation, which relates to the time when galaxy formed. • Each galaxy shows one peak of star formation, however star formation rate in NGC 185 decrease to the lower amount more steeply than SFR in NGC 147. � � � • The total mass loss rate is �. � × �� and �. � × �� ���� �� in NGC 147 and NGC 185 respectively. Galaxies of Many Colours: Star Formation Across 29 Wednesday, June 03, 2015 Cosmic Time Future Works: Map of Dust DUSTiNGS: follow up observations with INT JWST project: low metallicity environments Galaxies of Many Colours: Star Formation Across 32 Wednesday, June 03, 2015 Cosmic Time “No man is an island.” Galaxies of Many Colours: Star Formation Across 33 Wednesday, June 03, 2015 Cosmic Time Super AGB stars Galaxies of Many Colours: Star Formation Across 34 Wednesday, June 03, 2015 Cosmic Time Super AGB stars Galaxies of Many Colours: Star Formation Across 35 Wednesday, June 03, 2015 Cosmic Time Galaxies of Many Colours: Star Formation Across 36 Wednesday, June 03, 2015 Cosmic Time Galaxies of Many Colours: Star Formation Across 37 Wednesday, June 03, 2015 Cosmic Time Galaxies of Many Colours: Star Formation Across 38 Wednesday, June 03, 2015 Cosmic Time Galaxies of Many Colours: Star Formation Across 39 Wednesday, June 03, 2015 Cosmic Time Star Formation History �� = � � �� �(���) ��� ∫ � � �� ∫��� ���� � �� �(�) ��� �� � = ��(�) ��� �� � = � � �� ��� ∫��� ���� � � �� ∫��� ���� � � �� �(���) �� ∫ � � �� �� � = �� � �(�) ��� �� �� � = ��(�) ��� ∫��� ���� � �� �� ∫ � � � �� �(�) = �� () ∫() � � �� Galaxies of Many Colours: Star Formation Across 40 Wednesday, June 03, 2015 Cosmic Time Hot Bottom Burning http://moca.monash.edu/research/sins.html Galaxies of Many Colours: Star Formation Across 41 Wednesday, June 03, 2015 Cosmic Time 1.5 Mpc http://pixgood.com/local-group-diagram.html Galaxies of Many Colours: Star Formation Across 42 Wednesday, June 03, 2015 Cosmic Time http://essayweb.net/astronomy/blackhole.shtml) Galaxies of Many Colours: Star Formation Across 43 Wednesday, June 03, 2015 Cosmic Time.
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