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arXiv · 1506.04953

Distance and Reddening of the Enigmatic Gamma-ray-Detected Nova V1324 Sco

Thomas Finzell·Laura Chomiuk·Ulisse Munari·Frederick M. Walter
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Abstract

It has recently been discovered that some, if not all, classical novae emit GeV gamma-rays during outburst. Despite using an unreliable method to determine its distance, previous work showed that nova V1324 Sco was the most gamma-ray luminous of all gamma-ray-detected novae. We present here a different, more robust, method to determine the reddening and distance to V1324 Sco using high-resolution optical spectroscopy. Using two independent methods we derived a reddening of E(B-V) = 1.16 +/- 0.12 and a distance rD > 6.5 kpc. This distance is >40% greater than previously estimated, meaning that V1324 Sco has an even higher gamma-ray luminosity than previously calculated. We also use periodic modulations in the brightness, interpreted as the orbital period, in conjunction with pre-outburst photometric limits to show that a main-sequence companion is strongly favored.

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Thomas Finzell, Laura Chomiuk, Ulisse Munari, Frederick M. Walter. 2015-06-16. Distance and Reddening of the Enigmatic Gamma-ray-Detected Nova V1324 Sco. https://doi.org/10.1088/0004-637x%2F809%2F2%2F160

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