LINE DERIVED INFRARED EXTINCTION TOWARD THE GALACTIC CENTER

By Tobias K. Fritz, S. Gillessen, K. Dodds-Eden, D. Lutz, R. Genzel, W. Raab, T. Ott, O. Pfuhl, F. Eisenhauer, F. Yusef-Zadeh. 2011

156 citations recorded by the source corpus.

We derive the extinction curve toward the Galactic center (GC) from 1 to 19 μm. We use hydrogen emission lines of the minispiral observed by ISO-SWS and SINFONI. The extinction-free flux reference is the 2 cm continuum emission observed by the Very Large Array. Toward the inner 14″ × 20″, we find an extinction of A2.166 μm = 2.62 ± 0.11, with a power-law slope of α = −2.11 ± 0.06 shortward of 2.8 μm, consistent with the average near-infrared slope from the recent literature. At longer wavelengths, however, we find that the extinction is grayer than shortward of 2.8 μm. We find that it is not possible to fit the observed extinction curve with a dust model consisting of pure carbonaceous and silicate grains only, and the addition of composite particles, including ices, is needed to explain the observations. Combining a distance-dependent extinction with our distance-independent extinction, we derive the distance to the GC to be R0 = 7.94 ± 0.65 kpc. Toward Sgr A* (r < 0.″5), we obtain AH = 4.21 ± 0.10, AKs = 2.42 ± 0.10, and AL′ = 1.09 ± 0.13.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/0d0eb57e92119051193ec2b8a871561278bf3acd

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

Citations in the corpus

An Update on Monitoring Stellar Orbits in the Galactic Center (2016, background): “The optimum band is around 2µm wavelength, where the extinction screen amounts to less than 3 mag (Fritz et al. 2011), and where adaptive optics at 8 m-class telescopes is performing well for typical atmospheric conditions.”
REDDENING AND EXTINCTION TOWARD THE GALACTIC BULGE FROM OGLE-III: THE INNER MILKY WAY'S RV ∼ 2.5 EXTINCTION CURVE (2012, methodology): “Meanwhile, Zasowski et al. (2009) and Fritz et al. (2011) both found that the extinction law toward the inner Galaxy was shallower (greyer) in the mid-IR.”
The Galaxy in Context: Structural, Kinematic, and Integrated Properties (2016, methodology): “…Groenewegen & Blommaert (2005) Bulge Mirae B s 8.60 ± 0.81 FA14 Francis & Anderson (2014) Bulge red clump giants B s 7.50 ± 0.30 Ca+13 Cao et al. (2013) Bulge red clump giants B s 8.20 ± 0.20 Fr+11 Fritz et al. (2011) NSC red clump giants GC s 7.94 ± 0.76 FA14 Francis & Anderson (2014) All…”
The evolution of amorphous hydrocarbons in the ISM: dust modelling from a new vantage point (2013, background): “Fitzpatrick (2004), Fitzpatrick & Massa (2009) and Fritz et al. (2011) note that the IR extinction longward of 1 μm generally has a power-law type of behaviour.”
Detection of orbital motions near the last stable circular orbit of the massive black hole SgrA* (2018, background): “The average HK colour in the Galactic centre is 1.8mag (Fritz et al. 2011).”
First light for GRAVITY: Phase referencing optical interferometry for the Very Large Telescope Interferometer (2017, background): “1 mag corresponds to a B8V star at the Galactic center distance of 8.3 kpc (Gillessen et al. 2017) and K -band extinction of 2.7 mag (Fritz et al. 2011).”
Surface brightness profile of the Milky Way’s nuclear star cluster (2014, background): “Toward the GC it reaches minimum levels at mid-infrared (MIR) wavelengths of 3 − 5 µm (Nishiyama et al. 2009; Fritz et al. 2011).”