Project 1640 observations of the white dwarf HD 114174 B

Abstract

We present the first near infrared spectrum of the faint white dwarf companion HD 114174 B, obtained with Project 1640. Our spectrum, covering the Y, J and H bands, combined with previous TaRgetting bENchmark-objects with Doppler Spectroscopy (TRENDS) photometry measurements, allows us to place further constraints on this companion. We suggest two possible scenarios; either this object is an old, low-mass, cool H atmosphere white dwarf with Teff ∼ 3800 K or a high-mass white dwarf with Teff > 6000 K, potentially with an associated cool (Teff ∼ 700 K) brown dwarf or debris disc resulting in an infrared excess in the L band. We also provide an additional astrometry point for 2014 June 12 and use the modelled companion mass combined with the radial velocity and direct imaging data to place constraints on the orbital parameters for this companion.