We report the discovery of four transiting extrasolar planets (HAT-P-34b-HAT-P-37b) with masses ranging from 1.05 to 3.33 M sub(J) and periods from 1.33 to 5.45 days. These planets orbit relatively ...bright F and G dwarf stars (from V = 10.16 to V = 13.2). Of particular interest is HAT-P-34b which is moderately massive (3.33 M sub(J)), has a high eccentricity of e = 0.441 + or - 0.032 at a period of P = 5.452654 + or - 0.000016 days, and shows hints of an outer component. The other three planets have properties that are typical of hot Jupiters.
We report on the discovery of a planetary system with a close-in transiting hot Jupiter on a near circular orbit and a massive outer planet on a highly eccentric orbit. The inner planet, HAT-P-13b, ...transits the bright V = 10.622 G4 dwarf star GSC 3416 - 00543 every P = 2.916260 +/- 0.000010 days, with transit epoch Tc = 2454779.92979 +/- 0.00038 (BJD) and duration 0.1345 +/- 0.0017 days. The outer planet HAT-P-13c orbits the star every P 2 = 428.5 +/- 3.0 days with a nominal transit center (assuming zero impact parameter) of T 2c = 2454870.4 +/- 1.8 (BJD) or time of periastron passage T 2,peri = 2454890.05 +/- 0.48 (BJD). Transits of the outer planet have not been observed, and may not be present. The host star has a mass of 1.22+0.05 -0.10 M, radius of 1.56 +/- 0.08 R, effective temperature of 5653 +/- 90 K, and is rather metal-rich with Fe/H = +0.41 +/- 0.08. The inner planetary companion has a mass of 0.853+0.029 -0.046 M J, and radius of 1.281 +/- 0.079 R J, yielding a mean density of 0.498+0.103 -0.069 g cm-3. The outer companion has m 2sin i 2 = 15.2 +/- 1.0 M J, and orbits on a highly eccentric orbit of e 2 = 0.691 +/- 0.018. While we have not detected significant transit timing variations of HAT-P-13b, due to gravitational and light-travel time effects, future observations will constrain the orbital inclination of HAT-P-13c, along with its mutual inclination to HAT-P-13b. The HAT-P-13 (b, c) double-planet system may prove extremely valuable for theoretical studies of the formation and dynamics of planetary systems.
We report the discovery of HATS-1b, a transiting extrasolar planet orbiting the moderately bright V = 12.05 G dwarf star GSC 6652-00186, and the first planet discovered by HATSouth, a global network ...of autonomous wide-field telescopes. HATS-1b has a period of P approximately 3.4465 days, mass of M sub(p) approximately 1.86 M sub(J), and radius of R sub(p) approximately 1.30 R sub(J). The host star has a mass of 0.99 M sub(odot) and radius of 1.04 R sub(odot). The discovery light curve of HATS-1b has near-continuous coverage over several multi-day timespans, demonstrating the power of using a global network of telescopes to discover transiting planets.
Abstract
We report the discovery of HAT-P-67b, which is a hot-Saturn transiting a rapidly rotating F-subgiant. HAT-P-67b has a radius of
, and orbites a
,
host star in a ∼4.81 day period orbit. We ...place an upper limit on the mass of the planet via radial velocity measurements to be
, and a lower limit of
by limitations on Roche lobe overflow. Despite being a subgiant, the host star still exhibits relatively rapid rotation, with a projected rotational velocity of
, which makes it difficult to precisely determine the mass of the planet using radial velocities. We validated HAT-P-67b via two Doppler tomographic detections of the planetary transit, which eliminate potential eclipsing binary blend scenarios. The Doppler tomographic observations also confirm that HAT-P-67b has an orbit that is aligned to within 12°, in projection, with the spin of its host star. HAT-P-67b receives strong UV irradiation and is among one of the lowest density planets known, which makes it a good candidate for future UV transit observations in the search for an extended hydrogen exosphere.
We report the discovery of TOI 837b and its validation as a transiting planet. We characterize the system using data from the NASA Transiting Exoplanet Survey Satellite mission, the ESA Gaia mission, ...ground-based photometry from El Sauce and ASTEP400, and spectroscopy from CHIRON, FEROS, and Veloce. We find that TOI 837 is a T = 9.9 mag G0/F9 dwarf in the southern open cluster IC 2602. The star and planet are therefore million years old. Combining the transit photometry with a prior on the stellar parameters derived from the cluster color-magnitude diagram, we find that the planet has an orbital period of and is slightly smaller than Jupiter ( ). From radial velocity monitoring, we limit to less than 1.20 MJup (3 ). The transits either graze or nearly graze the stellar limb. Grazing transits are a cause for concern, as they are often indicative of astrophysical false-positive scenarios. Our follow-up data show that such scenarios are unlikely. Our combined multicolor photometry, high-resolution imaging, and radial velocities rule out hierarchical eclipsing binary scenarios. Background eclipsing binary scenarios, though limited by speckle imaging, remain a 0.2% possibility. TOI 837b is therefore a validated adolescent exoplanet. The planetary nature of the system can be confirmed or refuted through observations of the stellar obliquity and the planetary mass. Such observations may also improve our understanding of how the physical and orbital properties of exoplanets change in time.
As described in sect; 2.3, each HSsub 4 unit is controlled by a single control computer running Linux with a special kernel that is capable of real-time operations. In addition, a node-computer is ...responsible for weather sensing and synchronizing the time to the GPS time. A large suite of software is running on the control and node computers, responsible for the instrument control. We broadly classify the control software components to "low-level", meaning direct control of instruments, and "high-level", referring to more general observatory control, usually connected to the "low-level" software. The control of the telescope mount is performed through a Xenomai-based (real-time) character device driver, called the scope module. This module depends on the basic built-in printer port control modules of Linux. When the scope kernel module is loaded, a number of initial parameters are supplied, such as the choice of the hemisphere (to determine the direction of tracking), the resolution of the axes, settings for ramping up the motors to maximal slewing speed, and the level of verbosity.
In recent years, energy systems have been undergoing a development trend characterised by privatisation of the most important energy sectors (electricity and natural gas) that has turned former ...monopolies into free-market competitors. Furthermore, community awareness of environmental impact caused by large conventional power plants is growing, together with a greater interest in distributed-generation (DG) technologies based upon renewable energy sources (RES) and cogeneration. In this context, renewable energy technologies are emerging as potentially strong competitors for more widespread use. Despite the remarkable progress attained over the past decades, RES have not yet been fully integrated into the power sector. Some RES-technologies have already achieved a significant market share. The industry is now quite mature, although far from having developed its global potential.
This paper deals with the current status of DG in Greece and the presentation of a 60
kWp PV power station, developed under Law 3468/06 “Production of Electricity from Renewable Energy Sources, High Efficiency Cogeneration of Heat and Power and Other Deνices”. This application is the first DG installation with fixed PV modules implemented in the country after the approval of Law 3468/06. Cash flow economic analysis of the developed DG installation is performed and the experiences related to the potential of DG in Greek electricity market is presented and discussed.
We report the discovery by the HATSouth network of HATS-7b, a transiting Super-Neptune with a mass of 0.120 + or - 0.012 MsubJ, a radius of 0.563 + 0.046 - 0.034 RsubJ, and an orbital period of ...3.1853 days. The host star is a moderately bright K dwarf star with a mass of 0.849 + or - 0.027 MsubS, a radius of 0.815 + 0.049 - 0.035 RsubS, and a metallicity of Fe/H= +0.250 + or - 0.080. HATS-7b, which, together with the recently discovered HATS-8b, is one of the first two transiting Neptunes discovered in the Southern sky, is a prime target for additional follow-up observations with southern hemisphere facilities to characterize the atmospheres of super-Neptunes.
We report the measurement of a spin-orbit misalignment for WASP-79b, a recently discovered, bloated hot Jupiter from the Wide Angle Search for Planets (WASP) survey. Data were obtained using the ...CYCLOPS2 optical-fiber bundle and its simultaneous calibration system feeding the UCLES spectrograph on the Anglo-Australian Telescope. We have used the Rossiter-McLaughlin effect to determine the sky-projected spin-orbit angle to be lambda = (ProQuest: Formulae and/or non-USASCII text omitted). This result indicates a significant misalignment between the spin axis of the host star and the orbital plane of the planet-the planet being in a nearly polar orbit. WASP-79 is consistent with other stars that have T sub(eff) > 6250 K and host hot Jupiters in spin-orbit misalignment.
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 = 3.5479 days, mass of M sub(p) = 1.07 M sub(J), ...and radius of R sub(p) = 1.38 R sub(J). Given the radius of the planet, the brightness of the host star, and the stellar rotational velocity (v sin i = 9.0 km s super(-1)), 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 log g and T sub(eff) 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 super(-1).
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