Upgrade to Pro — share decks privately, control downloads, hide ads and more …

Julia's intro talk

Julia's intro talk

Julia Roman-Duval

February 15, 2018
Tweet

Other Decks in Science

Transcript

  1. In a nutshell… • I went to aerospace engineering school

    (“Grande Ecole”) in France • Got my PhD from Boston University in 2009 • I have been at STScI since 2009 • 2 year postdoc with Karl and Margaret • ESA-AURA Astronomer since 2011
  2. Quantifying diffuse and dense molecular gas in the milky way

    • In the Milky Way, we can spatially resolve different gas components • We use large-scale surveys of 12CO and 13CO * Galactic Ring Survey (GRS, 13CO) * University of Massachusetts Stony Brook survey (UMSB) in 12CO * EXeter-FCRAO survey (EXFC) in 12CO and 13CO (outer Galaxy) * ThrUMMS survey (12CO and 13CO) * 45” beam • Follow a statistical method, no cloud decomposition • See Roman-Duval+2016 for details GRS + UMSB EXFC 55-100 EXFC 135-165 ThRUMMS New in 2017
  3. DIFFUSE AND DENSE MOLECULAR GAS Integrated intensity maps of the

    diffuse and dense CO gas in the Outer Galaxy (135°<l<165° , -4°<b<5°, clouds roughly 3 kpc away). GRS GRS (Inner Galaxy) I(12CO) [K km/s] DIFFUSE DENSE
  4. Spatial distribution of CO gas in the Milky Way Face-on

    surface density computed on 100 pc scales in the total, diffuse, and dense components TOTAL DENSE DIFFUSE GRS+UMSB EXFC ThrUMMS GC GC GC +2 kpc +2 kpc +2 kpc Roman-Duval+2016
  5. Radial distribution of diffuse and dense gas • The fraction

    of diffuse gas increases from 10-20% at Rgal =2-6 kpc, to 50% beyond the Solar Circle Rgal [kpc] S gal (H2 ) [Mo pc-2] Dense/total ratio Dense Diffuse GRS GMCs The diffuse CO gas represents 25% of the total H 2 mass (6.5×108 M o ) Roman-Duval+2016
  6. Turbulence in GMCs • Characterized turbulence statistics in HD simulations

    and observations (CO 1-0): Turbulence is intermittent (Burgers type, shocks) Roman-Duval+2011 CO Observations CO Simulations
  7. ALMA in the LMC and SMC SMC N42 CO 1-0

    (ALMA) Spitzer 8 µm Spitzer 24 µm Spitzer 24 µm CO 1-0 (NANTEN) Ha 15 pc
  8. Success! • Derived dust masses (Gordon+2014) • Derived HI/H2 transition

    and G/D in atomic gas vs molecular gas (Roman- Duval+2014) H/D molecular gas < 200 H/D atomic gas = 380 HI/H2 transition at S(HI) = 40 Mo pc-2 Hydrogen Surface Density [Mo pc-2] Dust Surface Density [Mo pc-2]
  9. Beating the systematics with hi-resolution + all-sky surveys • Roman-Duval+2017

    Depletions Depletions IRAS + Planck + 21 cm + CO IRAS+ Planck + 21 cm + CO
  10. The METAL HST Project 101 prime (STIS/COS) + 101 parallel

    (WFC3) orbits with HST to probe the variations of dust properties and abundance and the growth and destruction of dust grains in the LMC ISM at Z = 0.5 Zo ✕ Metal Targets (33) O SN remnants (Temim+2015) HI (Kim+2003) Herschel/PACS 160 µm (Meixner+2013) CO 1-0 (MAGMA, Wong+2011) GO- 13778 (PI Jenkins) is obtaining similar spectra in the SMC at Z = 0.2 Zo J. Roman-Duval 21
  11. Marathon Olympic team trials (2016) Boston Marathon 2017 California International

    Marathon (2015) This is me This is Desiree Linden!!!!!