MASCARA-2 b

Abstract

In this paper we present MASCARA-2 b, a hot Jupiter transiting the mV = 7.6 A2 star HD 185603. Since early 2015, MASCARA has taken more than 1.6 million flux measurements of the star, corresponding to a total of almost 3000 h of observations, revealing a periodic dimming in the flux with a depth of 1.3%. Photometric follow-up observations were performed with the NITES and IAC80 telescopes and spectroscopic measurements were obtained with the Hertzsprung SONG telescope. We find MASCARA-2 b orbits HD 185603 with a period of 3.4741119-0.000006+0.000005 days at a distance of 0.057 ± 0.006 au, has a radius of 1.83 ± 0.07 RJ and place a 99% upper limit on the mass of <17 MJ. HD 185603 is a rapidly rotating early-type star with an effective temperature of 8980-130+90 K and a mass and radius of 1.89-0.05+0.06 M⊙, 1.60 ± 0.06 R⊙, respectively. Contrary to most other hot Jupiters transiting early-type stars, the projected planet orbital axis and stellar spin axis are found to be aligned with λ = 0.6 ± 4°. The brightness of the host star and the high equilibrium temperature, 2260 ± 50 K, of MASCARA-2 b make it a suitable target for atmospheric studies from the ground and space. Of particular interest is the detection of TiO, which has recently been detected in the similarly hot planets WASP-33 b and WASP-19 b.

KELT-21b: A Hot Jupiter Transiting the Rapidly Rotating Metal-poor Late-A Primary of a Likely Hierarchical Triple System

“…0 h m s = , decl.=+31°39′56 2 J2000.0). This is the same field that also yielded our other two most rapidly rotating planet hosts, KELT-9b ) and KELT-20b/ MASCARA-2b (Lund et al 2017;Talens et al 2017b), as well as KELT-8b (Fulton et al 2015). In the analysis of 6783 observations of HD 332124 obtained between 2007 May 29 and 2014 November 25 UT, we identified a candidate transit signal with a period of 3.612782 days and a depth of 1%; the target was given the KELT candidate ID of KC11C039077.…”

“…We show known transiting planets taken from the NASA Exoplanet Archive (https://exoplanetarchive. ipac.caltech.edu/), plus KELT-19Ab (Siverd et al 2018), KELT-20b/ MASCARA-2b (Lund et al 2017;Talens et al 2017b), and MASCARA-1b (Talens et al 2017a). The location of KELT-21b is marked.…”

“…KELT-21 is well above the Kraft break, where hot Jupiters tend to have a wide range of misalignments (Winn et al 2010). Although its well-aligned orbit is somewhat unusual in this context, some other hot Jupiters around hot stars are also aligned, such as KELT-7b (Zhou et al 2016a) and KELT-20b/MASCARA-2b (Lund et al 2017;Talens et al 2017b). Even for an isotropic distribution of misalignments, some systems should be aligned by chance.…”

KELT-20b: A Giant Planet with a Period of P ∼ 3.5 days Transiting the V ∼ 7.6 Early A Star HD 185603

“…Note added in proof.. During the preparation of this paper, our team became aware of another paper by The Multi-site All-Sky CAmeRA (MASCARA) Collaboration (Talens et al 2017b) reporting the discovery of a planetary companion to the host star discussed here, HD 185603 (Talens et al 2017a). While we assume that this planetary companion is indeed , no information about the analysis Figure 14.…”

KELT-19Ab: A P ∼ 4.6-day Hot Jupiter Transiting a Likely Am Star with a Distant Stellar Companion

“…To date, this strategy of targeting hot stars has led to the discovery of four planets transiting A stars by the KELT survey: KELT-17b (Zhou et al 2016b), KELT-9b (Gaudi et al 2017), KELT-20b/MASCARA-2b (Lund et al 2017;Talens et al 2017b), and , the planet announced here. Additionally, there are four planets known to transit A stars discovered by other collaborations: WASP-33b (Collier Cameron et al 2010), Kepler-13Ab (Shporer et al 2011), HAT-P-57b (Hartman et al 2015), and MASCARA-1b (Talens et al 2017a).…”