A New Galactic Extinction Map in High Ecliptic Latitudes

Abstract

In this study, we derived a galactic extinction map in high ecliptic latitudes for $ \mid{\beta}\mid$$ >$ 30$ ^\circ$ . The dust temperature distribution was derived from the intensities at 100 and 140 $ \mu$ m with a spatial resolution of 5$ '$ . The intensity at 140 $ \mu$ m was derived from the intensities at 60 and 100 $ \mu$ m of the IRAS data, assuming two tight correlations between the intensities at 60, 100, and 140 $ \mu$ m of the COBE/DIRBE data. We found that these correlations can be separated into two correlations by the antenna temperature of the radio continuum at 41 GHz. Because the present study can trace the 5$ '$-scale spatial variation in the dust temperature distribution, it has an advantage over the extinction map derived by Schlegel, Finkbeiner, and Davis (1998, ApJ, 500, 525), who used the DIRBE maps to derive the dust temperature distribution with a spatial resolution of 1$ ^\circ$ . We estimated the accuracy of our method by comparing it with that of Schlegel, Finkbeiner, and Davis (1998, ApJ, 500, 525). The spatial-resolution difference was found to be significant. The area in which the significant difference is confirmed occupies 28% of the region for $ \mid{\beta}\mid$$ >$ 30$ ^\circ$ . With respect to the estimated extragalactic reddening, the present study has an advantage over the extinction map derived by Dobashi (2011, PASJ, 63, 1), which was based on the 2MASS Point Source Catalog, because our extinction map was derived based on far-infrared emission. Dobashi's extinction map exhibits a maximum value that is lower than that of our map in the galactic plane, and a signal-to-noise ratio that is lower than that of our map in high galactic latitudes. This significant difference is confirmed in 81% of the region for $ \mid{\beta}\mid$$ >$ 30$ ^\circ$ . In the areas where the significant differences are confirmed, the extinction should be estimated using our method, rather than the previous methods.

The Panchromatic Hubble Andromeda Treasury. Viii. A Wide-Area, High-Resolution Map of Dust Extinction in M31

“…Although the reddening parameters are derived independently for each spatial pixel, there are clear coherent features in all the derived parameters across the area, on scales larger than the one pixel coherence expected solely from oversampling the 25 pc pixel grid. The distribution of dust extinction shows clear filamentary structure throughout the kiloparsec-scale regions, and is reminiscent of large scale maps within the Milky Way (e.g., Schlegel et al 1998;Froebrich et al 2007;Kohyama et al 2013;Lombardi et al 2011;Schlafly & Finkbeiner 2011;Nidever et al 2012). There is also obvious large scale coherence in the spatial distribution of the reddening fraction f red .…”

Diffuse Interstellar Band at 8620 Å in Rave: A New Method for Detecting the Diffuse Interstellar Band in Spectra of Cool Stars

“…mate the reddening (Yasuda et al 2007;Kohyama et al 2013) and because most stars have lower reddening than the calculated limit, the real errors are much lower than that. Several spectra are averaged to produce the stellar spectrum with higher S/N ratio, so any stars with possible peculiar high reddening are averaged out.…”

The 3-Dimensional Distribution of Interstellar Dust

“…Notably, they found that the Local Cavity, the large volume of hot gas around the Sun, is present both in the gas and the dust. However, they also found that the opacity was higher in the dust in the Northern 218 J. Murthy Gontcharov (2012) 2M ASS + Hipparcos photometry Gontcharov (2013) 2M ASS + W ISE photometry Spatial variations of Extinction Law Kohyama et al (2013) total extinction from IRAS emission Sale (2012) Bayesian models M odeling only hemisphere as compared to the Southern, an asymmetry not seen in the gas. This implies that the gas to dust ratio is higher in the Northern hemisphere, a conclusion also drawn by (Knude & Høg 1999).…”