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Title: Mapping the Extinction Curve in 3D: Structure on Kiloparsec Scales

Abstract

Near-infrared spectroscopy from APOGEE and wide-field optical photometry from Pan-STARRS1 have recently made precise measurements of the shape of the extinction curve possible for tens of thousands of stars, parameterized by R ( V ). These measurements revealed structures in R ( V ) with large angular scales, which are challenging to explain in existing dust paradigms. In this work, we combine three-dimensional maps of dust column density with R ( V ) measurements to constrain the three-dimensional distribution of R ( V ) in the Milky Way. We find that the variations in R ( V ) are correlated on kiloparsec scales. In particular, most of the dust within one kiloparsec in the outer Galaxy, including many local molecular clouds (Orion, Taurus, Perseus, California, and Cepheus), has a significantly lower R ( V ) than more distant dust in the Milky Way. These results provide new input to models of dust evolution and processing, and complicate the application of locally derived extinction curves to more distant regions of the Milky Way and to other galaxies.

Authors:
 [1];  [2];  [3];  [4]
  1. Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720 (United States)
  2. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
  3. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  4. Kavli Institute for Particle Astrophysics and Cosmology, Physics and Astrophysics Building, 452 Lomita Mall, Stanford, CA 94305 (United States)
Publication Date:
OSTI Identifier:
22661246
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 838; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABSORPTION SPECTROSCOPY; CLOUDS; DENSITY; DISTRIBUTION; EVOLUTION; INFRARED SPECTRA; MILKY WAY; PHOTOMETRY; STARS; THREE-DIMENSIONAL CALCULATIONS

Citation Formats

Schlafly, E. F., Peek, J. E. G., Finkbeiner, D. P., and Green, G. M. Mapping the Extinction Curve in 3D: Structure on Kiloparsec Scales. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA619D.
Schlafly, E. F., Peek, J. E. G., Finkbeiner, D. P., & Green, G. M. Mapping the Extinction Curve in 3D: Structure on Kiloparsec Scales. United States. doi:10.3847/1538-4357/AA619D.
Schlafly, E. F., Peek, J. E. G., Finkbeiner, D. P., and Green, G. M. Mon . "Mapping the Extinction Curve in 3D: Structure on Kiloparsec Scales". United States. doi:10.3847/1538-4357/AA619D.
@article{osti_22661246,
title = {Mapping the Extinction Curve in 3D: Structure on Kiloparsec Scales},
author = {Schlafly, E. F. and Peek, J. E. G. and Finkbeiner, D. P. and Green, G. M.},
abstractNote = {Near-infrared spectroscopy from APOGEE and wide-field optical photometry from Pan-STARRS1 have recently made precise measurements of the shape of the extinction curve possible for tens of thousands of stars, parameterized by R ( V ). These measurements revealed structures in R ( V ) with large angular scales, which are challenging to explain in existing dust paradigms. In this work, we combine three-dimensional maps of dust column density with R ( V ) measurements to constrain the three-dimensional distribution of R ( V ) in the Milky Way. We find that the variations in R ( V ) are correlated on kiloparsec scales. In particular, most of the dust within one kiloparsec in the outer Galaxy, including many local molecular clouds (Orion, Taurus, Perseus, California, and Cepheus), has a significantly lower R ( V ) than more distant dust in the Milky Way. These results provide new input to models of dust evolution and processing, and complicate the application of locally derived extinction curves to more distant regions of the Milky Way and to other galaxies.},
doi = {10.3847/1538-4357/AA619D},
journal = {Astrophysical Journal},
number = 1,
volume = 838,
place = {United States},
year = {Mon Mar 20 00:00:00 EDT 2017},
month = {Mon Mar 20 00:00:00 EDT 2017}
}
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