Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userDiscovery of an inflated hot Jupiter around a slightly evolved star TOI-1789
368
0
0.0
(
0
)
Added by
Akanksha Khandelwal
Publication date
2021
fields
Physics
and research's language is
English
Ask ChatGPT about the research
No Arabic abstract
We report here the discovery of a hot Jupiter at an orbital period of $3.208666pm0.000016$ days around TOI-1789 (TYC 1962-00303-1, $TESS_{mag}$ = 9.1) based on the TESS photometry, ground-based photometry, and high-precision radial velocity observations. The high-precision radial velocity observations were obtained from the high-resolution spectrographs, PARAS at Physical Research Laboratory (PRL), India, and TCES at Thuringer Landessternwarte Tautenburg (TLS), Germany, and the ground-based transit observations were obtained using the 0.43~m telescope at PRL with the Bessel-$R$ filter. The host star is a slightly evolved ($log{g_*}$ = $3.939^{+0.024}_{-0.046}$), late F-type ($T_{eff}$ = $5984^{+55}_{-57}$ K), metal-rich star ([Fe/H] = $0.370^{+0.073}_{-0.089}$ dex) with a radius of {ensuremath{$R_{*}$}} = $2.172^{+0.037}_{-0.035}$ (R_odot) located at a distance of $223.56^{+0.91}_{-0.90}$ pc. The simultaneous fitting of the multiple light curves and the radial velocity data of TOI-1789 reveals that TOI-1789b has a mass of $M_{P}$ = $0.70pm0.16 $ $M_{J}$, a radius of $R_{P}$ = $1.40^{+0.22}_{-0.13}$ $R_{J}$, and a bulk density of $rho_P$ = $0.31^{+0.15}_{-0.13}$ g cm$^{-3}$ with an orbital separation of a = $0.04873^{+0.00065}_{-0.0016}$ AU. This puts TOI-1789b in the category of inflated hot Jupiters. It is one of the few nearby evolved stars with a close-in planet. The detection of such systems will contribute to our understanding of mechanisms responsible for inflation in hot Jupiters and also provide an opportunity to understand the evolution of planets around stars leaving the main sequence branch.
rate research
Read More
We report the discovery of KELT-12b, a highly inflated Jupiter-mass planet transiting a mildly evolved host star. We identified the initial transit signal in the KELT-North survey data and established the planetary nature of the companion through precise follow-up photometry, high-resolution spectroscopy, precise radial velocity measurements, and high-resolution adaptive optics imaging. Our preferred best-fit model indicates that the $V = 10.64$ host, TYC 2619-1057-1, has $T_{rm eff} = 6278 pm 51$ K, $log{g_star} = 3.89^{+0.054}_{-0.051}$, and [Fe/H] = $0.19^{+0.083}_{-0.085}$, with an inferred mass $M_{star} = 1.59^{+0.071}_{-0.091} M_odot$ and radius $R_star = 2.37 pm 0.18 R_odot$. The planetary companion has $M_{rm P} = 0.95 pm 0.14 M_{rm J}$, $R_{rm P} = 1.79^{+0.18}_{-0.17} R_{rm J}$, $log{g_{rm P}} = 2.87^{+0.097}_{-0.098}$, and density $rho_{rm P} = 0.21^{+0.075}_{-0.054}$ g cm$^{-3}$, making it one of the most inflated giant planets known. The time of inferior conjunction in ${rm BJD_{TDB}}$ is $2457088.692055 pm 0.0009$ and the period is $P = 5.0316144 pm 0.0000306$ days. Despite the relatively large separation of $sim0.07$ AU implied by its $sim 5.03$-day orbital period, KELT-12b receives significant flux of $2.93^{+0.33}_{-0.30} times 10^9$ erg s$^{-1}$ cm$^{-2}$ from its host. We compare the radii and insolations of transiting gas-giant planets around hot ($T_{rm eff} geq 6250$ K) and cool stars, noting that the observed paucity of known transiting giants around hot stars with low insolation is likely due to selection effects. We underscore the significance of long-term ground-based monitoring of hot stars and space-based targeting of hot stars with the Transiting Exoplanet Survey Satellite (TESS) to search for inflated giants in longer-period orbits.
We report the discovery by the HATSouth survey of HATS-3b, a transiting extrasolar planet orbiting a V=12.4 F-dwarf star. HATS-3b has a period of P = 3.5479d, mass of Mp = 1.07MJ, and radius of Rp = 1.38RJ. Given the radius of the planet, the brightness of the host star, and the stellar rotational velocity (vsini = 9.0km/s), this system will make an interesting target for future observations to measure the Rossiter-McLaughlin effect and determine its spin-orbit alignment. We detail the low/medium-resolution reconnaissance spectroscopy that we are now using to deal with large numbers of transiting planet candidates produced by the HATSouth survey. We show that this important step in discovering planets produces logg and Teff parameters at a precision suitable for efficient candidate vetting, as well as efficiently identifying stellar mass eclipsing binaries with radial velocity semi-amplitudes as low as 1 km/s.
We report the discovery by the WASP transit survey of a highly-irradiated, massive (2.242 +/- 0.080 MJup) planet which transits a bright (V = 10.6), evolved F8 star every 2.9 days. The planet, WASP-71b, is larger than Jupiter (1.46 +/- 0.13 RJup), but less dense (0.71 +/- 0.16 {rho}Jup). We also report spectroscopic observations made during transit with the CORALIE spectrograph, which allow us to make a highly-significant detection of the Rossiter-McLaughlin effect. We determine the sky-projected angle between the stellar-spin and planetary-orbit axes to be {lambda} = 20.1 +/- 9.7 degrees, i.e. the system is aligned, according to the widely-used alignment criteria that systems are regarded as misaligned only when {lambda} is measured to be greater than 10 degrees with 3-{sigma} confidence. WASP-71, with an effective temperature of 6059 +/- 98 K, therefore fits the previously observed pattern that only stars hotter than 6250 K are host to planets in misaligned orbits. We emphasise, however, that {lambda} is merely the sky-projected obliquity angle; we are unable to determine whether the stellar-spin and planetary-orbit axes are misaligned along the line-of-sight. With a mass of 1.56 +/- 0.07 Msun, WASP-71 was previously hotter than 6250 K, and therefore might have been significantly misaligned in the past. If so, the planetary orbit has been realigned, presumably through tidal interactions with the cooling stars growing convective zone.
We report the discovery of HAT-P-24b, a transiting extrasolar planet orbiting the moderately bright V=11.818 F8 dwarf star GSC 0774-01441, with a period P = 3.3552464 +/- 0.0000071 d, transit epoch Tc = 2455216.97669 +/- 0.00024 (BJD_UTC), and transit duration 3.653 +/- 0.025 hours. The host star has a mass of 1.191 +/- 0.042 Msun, radius of 1.317 +/- 0.068 Rsun, effective temperature 6373 +/- 80 K, and a low metallicity of [Fe/H] = -0.16 +/- 0.08. The planetary companion has a mass of 0.681 +/- 0.031 MJ, and radius of 1.243 +/- 0.072 RJ yielding a mean density of 0.439 +/- 0.069 g cm-3 . By repeating our global fits with different parameter sets, we have performed a critical investigation of the fitting techniques used for previous HAT planetary discoveries. We find that the system properties are robust against the choice of priors. The effects of fixed versus fitted limb darkening are also examined. HAT-P-24b probably maintains a small eccentricity of e = 0.052 +0.022 -0.017, which is accepted over the circular orbit model with false alarm probability 5.8%. In the absence of eccentricity pumping, this result suggests HAT-P-24b experiences less tidal dissipation than Jupiter. Due to relatively rapid stellar rotation, we estimate that HAT-P-24b should exhibit one of the largest known Rossiter-McLaughlin effect amplitudes for an exoplanet (deltaVRM ~ 95 m/s) and thus a precise measurement of the sky-projected spin-orbit alignment should be possible.
We report the discovery of a new transiting planet from the WASP survey. WASP-135b is a hot Jupiter with a radius of 1.30 pm 0.09 Rjup, a mass of 1.90 pm 0.08 Mjup and an orbital period of 1.401 days. Its host is a Sun-like star, with a G5 spectral type and a mass and radius of 0.98 pm 0.06 Msun and 0.96 pm 0.05 Rsun respectively. The proximity of the planet to its host means that WASP-135b receives high levels of insolation, which may be the cause of its inflated radius. Additionally, we find weak evidence of a transfer of angular momentum from the planet to its star.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
