2017 Pasadena Astronomy Postdoc Mixer

10-minute talk with lots of pretty pictures to stimulate conversations and discussions for the Pasadena Astronomy Postdoc Mixer

Transcript

1. Daniel Lenz,
   Pasadena Postdoc mixer, May 25
   Dust and gas in the
   Milky Way
   Implications for cosmological
   foregrounds
   

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2. Disclaimer
   

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3. Disclaimer
   ❖ Just slightly scientific
   

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4. Disclaimer
   ❖ Just slightly scientific
   ❖ Pretty pictures are key!
   

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5. Disclaimer
   ❖ Just slightly scientific
   ❖ Pretty pictures are key!
   ❖ Talk to me about:
   ❖ HI
   ❖ Observational multiphase ISM
   ❖ CIB/CMB component separation
   ❖ Dust/Reddening
   ❖ Machine learning, Bayesian models, python, Mac OS
   

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6. On Galactic HI
   ❖ Very abundant, easy to detect
   ❖ Key to understanding galaxy evolution
   ❖ How do galaxies replenish their star-formation fuel?
   ❖ Important for foreground modeling of cosmological
   signals
   

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7. On Galactic HI
   4
   Credit: S. Janowiecki
   Southern hemisphere:
   Galactic All-Sky
   Survey (GASS)
   McClure-Griffiths+
   (2009)
   
   Kalberla+ (2010, 2015)
   D. McClenaghan
   

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8. On Galactic HI
   4
   B. Winkel
   Northern hemisphere:
   Effelsberg-Bonn HI
   Survey (EBHIS)
   Kerp+ (2011)
   
   Winkel+ (2010, 2016)
   

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11. Multiphase ISM
    HI Dust
    

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12. Multiphase ISM
    -15.9797 184.878
    K km s 1 -1 3.8
    log10
    (Rayleighs)
    -1.00791 1.24339
    log10
    (Counts)
    ❖ There is so much more!
    ❖ No need for more data,
    just need to be smarter
    H⍺
    -rays
    CII
    

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13. WISE
    Lang (2014), Meisner+ (2016)
    

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14. WISE
    Lang (2014), Meisner+ (2016)
    

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15. The Cosmic Infrared Background
    

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16. The Cosmic Infrared Background
    

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17. The Cosmic Infrared Background
    ❖ Made up from dust in star-
    forming galaxies at z = 1..2
    ❖ Used for
    ❖ cosmic evolution of the star
    formation rate
    ❖ tracer of the density field
    Lagache+ (2005)
    

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18. CIB: Galactic poles
    12
    Total FIR intensity
    

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19. CIB: Galactic poles
    12
    CIB
    

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20. Reddening
    

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21. Reddening
    ❖ E(B-V) = Extinction in B band - Extinction in V band
    ❖ More dust => larger E(B-V)
    ❖ E(B-V) maps essential for correcting observations for Galactic
    reddening
    ❖ Schlegel, Finkbeiner, Davis (1998) still state-of-the-art
    

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22. Reddening
    ❖ E(B-V) = Extinction in B band - Extinction in V band
    ❖ More dust => larger E(B-V)
    ❖ E(B-V) maps essential for correcting observations for Galactic
    reddening
    ❖ Schlegel, Finkbeiner, Davis (1998) still state-of-the-art
    

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23. Independent SFD corrections
    -0.01 0.01
    SFD - PG10 [mag] -0.01 0.01
    SFD - Model [mag]
    ❖ Peek & Graves (2010)
    
    ❖ Based on elliptical galaxies
    ❖ Lenz & Hensley (2017, WSNW)
    
    ❖ Based on Galactic HI
    

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24. Thanks!
    ❖ Talk to me about:
    ❖ HI
    ❖ Observational multiphase ISM
    ❖ CIB/CMB component separation
    ❖ Dust/Reddening
    ❖ Machine learning, Bayesian models, python, Mac
    OS
    

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