The Dow ended at a record high on Friday, boosted by IBM, while a rebound in high-growth momentum names helped the broader market.Consumer discretionary shares also lifted the market, with the stock of Gap Inc (GPS.N) up 3.3 percent at $40.52 after the apparel retailer reported upbeat April sales and gave a profit forecast that surpassed Wall Street’s expectations. The S&P consumer discretionary index .SPLRCD was up 0.6 percent.Apple Inc (AAPL.O) was the biggest drag on both the benchmark S&P 500 index and the Nasdaq 100 .NDX on news that it is close to paying a record $3.2 billion for Beats Electronics, an expensive foray into music streaming and headphone gear, two people with knowledge of the matter said.Some analysts questioned whether Beats, valued at $1 billion during its last funding round in September, was worth that price. Apple shares fell 0.4 percent to $585.54.Momentum names advanced, with shares of Gilead Sciences Inc (GILD.O) up 1.3 percent at $79.76. Netflix Inc (NFLX.O) shares rose 2.1 percent to $328.55 after the company increased the price of its most popular video streaming plan by $1 a month.The gains came after a volatile week for those shares. The S&P 500 has alternated between gains and losses each day this week, and the Nasdaq has dropped for three straight sessions – its longest losing streak since early April – as Internet-related stocks came under pressure.Trading was mostly lackluster, with about 5.7 billion shares changing hands on the U.S. exchanges, below the 6.2 billion month-to-date average, according to data from BATS Global Markets.”The volatility and the decline in a lot of growth stuff is wearing people out,” said Michael James, managing director of equity trading at Wedbush Securities in Los Angeles. “There’s a lot of trader fatigue.”The Dow Jones industrial average .DJI rose 32.37 points or 0.2 percent, to 16,583.34, the S&P 500 .SPX gained 2.85 points or 0.15 percent, to 1,878.48 and the Nasdaq Composite.IXIC added 20.374 points or 0.5 percent, to 4,071.869.Shares of International Business Machines Corp (IBM.N) rose 0.6 percent to $190.08 and helped lift the Dow to a record close.For the week, the Dow rose 0.4 percent, while the S&P 500 dipped 0.1 percent and the Nasdaq fell 1.3 percent. This marked the Nasdaq’s biggest weekly percentage decline in a month.The Russell 2000 .TOY gained 0.9 percent. Early in the session, it flirted with correction territory, defined as a 10 percent drop from a recent peak. At its session low, the Russell touched 1,091.50, nearly 10 percent below its all-time closing high of 1,208.65 reached on March 4.Healthcare stocks rose, with shares of Merck (MRK.N) up 0.7 percent at $55.21 a day after U.S. health regulators approved a blood-clot prevention drug developed by Merck for use by patients who have had a heart attack or who suffer from blockages in the arteries of the legs. The S&P healthcare index .SPXHC was up 0.6 percent.Among the day’s big decliners, Rocket Fuel Inc (FUEL.O) shares tumbled 21.5 percent to $21.83 after the technology provider for Web-based video advertising forecast current-quarter revenue far below expectations, prompting downgrades from Goldman Sachs and BMO Capital.Advancers outnumbered decliners on the New York Stock Exchange by a ratio of about 17 to 13, while on the Nasdaq, nearly 17 stocks rose for every nine that fell.
Phase folded light curve and the best fitting transit model of EPIC 219654213. Gray points are the measurements, black circles the binned data. The continuous line represents the best fitted model. Residuals to the fit are shown in the lower panel. Credit: Eigmuller et al., 2018. © 2018 Phys.org Explore further This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Citation: New binary system showcasing beaming effect found by astronomers (2018, September 5) retrieved 18 August 2019 from https://phys.org/news/2018-09-binary-showcasing-effect-astronomers.html An international team of astronomers has discovered a new eclipsing binary system composed of an M-dwarf orbiting a main sequence star. The transiting dwarf star exhibits the so-called relativistic beaming effect. The finding is reported in a paper published August 20 on the arXiv pre-print repository. Journal information: Monthly Notices of the Royal Astronomical Society Astronomers detect a doubly eclipsing quadruple star system The relativistic beaming effect, also known as Doppler boosting, is the process by which relativistic effects modify the apparent luminosity of emitting matter that is moving at speeds close to the speed of light. The process is caused by the reflex motion of the stars introducing photometric flux variations due to the Doppler effect.Measurements of the beaming effect are important for astronomers studying binary systems, as they allow independent estimate of the radial velocity of secondary components. This could be crucial in disclosing physical parameters and the nature of such systems.Now, using data from NASA Kepler spacecraft’s prolonged mission known as K2, a group of researchers led by Philipp Eigmuller of the German Aerospace Center (DLR) has studied the star EPIC 219654213, which was initially identified as a potential host for a planetary system.However, K2 data complemented by follow-up spectroscopic observations with ground based observatories, including Keck telescope, Nordic Optical Telescope (NOT) and McDonald Observatory, indicate that EPIC 219654213 is a binary star. The observational campaign allowed also the scientists to determine fundamental parameters of the newly found system.”In this paper, we present the detailed characterization of a DEB [detached eclipsing binary] formed by a main sequence star and an M dwarf companion with precise K2 photometry and ground-based radial velocity follow-up,” the astronomers wrote in the paper.The primary component of the system is a slightly evolved main sequence star of spectral type F7V. The star, about 4.1 billion years old, has a radius of approximately 1.52 solar radii and a mass similar to that of our sun.The companion is a dwarf star of spectral type M5V. It is about five times smaller and less massive than the sun. The dwarf is on a nearly circular orbit around the primary star, orbiting it every 5.44 days. The components of the system are separated by approximately 0.065 AU.The authors of the study also provided the details about the beaming effect observed in the system, focusing on its amplitude.”The results show a change in the amplitude of the beaming effect of 35ppm, which account for 50 percent of the observed discrepancy between expected and observed beaming effect,” the paper reads.In concluding remarks, the researchers noted that EPIC 219654213 should be further investigated using exoplanet-hunting missions such as NASA’s Transiting Exoplanet Survey Satellite (TESS) and ESA’s PLAnetary Transits and Oscillations of stars (PLATO). More observations of this system may confirm if its smaller component is indeed an M dwarf or a brown dwarf or, what is also possible, a highly inflated “hot Jupiter” exoplanet. More information: A transiting M-dwarf showing beaming effect in the field of Ruprecht 147, arXiv:1808.06325 [astro-ph.SR] arxiv.org/abs/1808.06325Ph Eigmüller et al. A transiting M-dwarf showing beaming effect in the field of Ruprecht 147, Monthly Notices of the Royal Astronomical Society (2018). DOI: 10.1093/mnras/sty2155AbstractWe report the discovery and characterization of an eclipsing M5V dwarf star, orbiting a slightly evolved F7V main sequence star. In contrast to previous claims in the literature, we confirm that the system does not belong to the galactic open cluster Ruprecht 147. We determine its fundamental parameters combining K2 time-series data with spectroscopic observations from the McDonald Observatory, FIES@NOT, and HIRES@KECK. The very precise photometric data from the K2 mission allows us to measure variations caused by the beaming effect (relativistic doppler boosting), ellipsoidal variation, reflection, and the secondary eclipse. We determined the radial velocity using spectroscopic observations and compare it to the radial velocity determined from the beaming effect observed in the photometric data. The M5V star has a radius of 0.200+0.007−0.008 R⊙ and a mass of 0.187+0.012−0.013 M⊙. The primary star has radius of 1.518+0.038−0.049 R⊙ and a mass of 1.008+0.081−0.097 M⊙. The orbital period is 5.441995±0.000007 days. The system is one of the few eclipsing systems with observed beaming effect and spectroscopic radial velocity measurements and it can be used as test case for the modelling of the beaming effect. Current and forthcoming space missions such as TESS and PLATO might benefit of the analysis of the beaming effect to estimate the mass of transiting companions without the need for radial velocity follow up observations, provided that the systematic sources of noise affecting this method are well understood.