The modern Champions League has not been a hospitable competition for underdogs. Real Madrid, Barcelona and Bayern Munich have won the last four trophies, and the closest thing to an upset winner in recent years was Chelsea in 2012. This season, though, might be different.Sure, Bayern, Barcelona and Real Madrid are all still in it. But no team left in the Champions League is historically dominant. Expected goals, a statistical measure of the quality of scoring chances a team creates and concedes, rates Barcelona as the top team in this year’s competition, but one with only a 28 percent change of winning the tournament.1All of the data in this article is current through April 10.This year’s Barcelona, however, does not make the top 10 list of expected goals difference for clubs since 2010-11. With fewer truly great teams in the mix, an upset winner is that much more likely. Here’s what to expect.Borussia Dortmund (60 percent chance of advancing) vs. Monaco (40 percent)With a position atop the Ligue 1 table, an impressive defeat of Manchester City in the round of 16, and an incredible 103 goals scored between Ligue 1 and the Champions League, Monaco might appear to have the resume of a quarterfinal favorite. However, Monaco’s numbers require some caution. Despite leading to 90 nonpenalty goals this season, the chances Monaco has created have been worth only about 58 expected goals (xG), according to the soccer stats-tracker Opta. Scoring 33 more goals than expected is unprecedented in the last few years. No other club has even beaten expected goals by 20 or more at this point in the season since 2010-11. While it is not terribly unusual for top teams to outperform their expected goals — top teams tend to have better finishers — Monaco is finishing chances better than any of Lionel Messi’s teams ever did.If Monaco’s goal scoring falls off, Dortmund should be well prepared to take advantage. Since returning from the winter break, Dortmund has been dominant, collecting 1.2 more xG per match than their opponents, compared with only a +0.7 margin before the break. With underlying numbers to match its goals difference and a recent spike in performance, Dortmund looks like the more likely semifinalist.In either case, this should be one of the most exciting matches of the round. Both Monaco and Dortmund depend on pace and quick-hitting attacks — both clubs lead their respective leagues in shot attempts following moves of two passes or fewer. While Thomas Tuchel may attempt to impose more control on the match than Pep Guardiola did against Monaco in the round of 16, the game is likely to be a fast-paced and attacking affair.Barcelona (65 percent) vs. Juventus (35 percent)This rematch of the 2015 Champions League final features the best attack-vs.-defense matchup of the round. This season Barcelona has created the second-most clear scoring chances (116), as defined by Opta, in the big five leagues, while Juventus has conceded the fewest clear scoring chances (20).Barcelona is well known for an attacking style that favors making the extra pass to create the highest-quality scoring chances, rather than trying to shoot the ball from far out. Juventus, under managers Max Allegri and Antonio Conte, has developed a defensive strategy that mirrors Barcelona’s attacking play. The Italian side focuses on defensive structure in order to prevent the same kinds of clear chances that Barca aims to create. A list of the best defensive seasons since 2010-11, judging teams by the number of quality chances they concede, shows Juventus dominating. And this year Juventus is preventing clear chances at its best rate ever, allowing only about one every other match.Barcelona was able to break through Juventus’ defense in the 2015 final just as Bayern Munich did during last year’s knockout stages. But in both of those cases, it took a top performance from one of the world’s best attacks to win the tie. Barcelona is rightly favored, but any slight drop-off in execution could see the Catalan side stymied by Juventus’ defense.Bayern Munich (71 percent) vs. Real Madrid (29 percent)ESPN’s Soccer Power Index rating gives a big boost to Bayern Munich based on the German side’s superior defensive numbers. Bayern has conceded just 23 goals in 36 matches between the Bundesliga and Champions League, while Real has conceded 43 in 38 matches. Some of this difference disappears when you look at expected goals, which drops Real’s total to 37. But it is not enough to erase it all.The two sides not only see different defensive outcomes, but they also play significantly different styles when out of possession. Carlo Ancelotti has his Bayern squad playing the high-pressing style preached by Pep Guardiola. When Bayern turns the ball over in midfield, it breaks up their opponents’ next possession within three passes about 55 percent of the time, the second-highest rate in the Bundesliga. Real Madrid, by contrast, defends much more passively, breaking up opposition possession in only about 45 percent of cases, 12th in La Liga.It is not that Real Madrid has been particularly poor defensively, but its more passive defensive style seems like a major risk against Bayern. Under manager Zinedine Zidane, Real Madrid has been an outlier among top clubs in not embracing the new, analytics-minded strategy of pressing on defense. It will be interesting to see if Real’s more old-fashioned defensive style can work. If Real fails to unsettle Bayern early in a possession, that would give time on the ball to central midfielders Arturo Vidal and Thiago Alcantara. That outcome would be risky at best for Real. Thiago in particular is having a great season, leading the Bundesliga with 96 progressive passes and runs. (These are defined as passes which advance the ball through midfield over 10 yards beyond where the possession had reached, or runs which progress similarly while eliminating a defender on the dribble.) Real Madrid may need to adjust its pressing rate to protect the defense from Bayern’s passers if it means to make it to another Champions League final.Atletico Madrid (75 percent) vs. Leicester City (25 percent)Leicester City presents something of a conundrum to any projection system, having won five of six league matches since sacking manager Claudio Ranieri. The club’s performances under new manager Craig Shakespeare have not been quite as good as its unbeaten record suggests — despite outscoring opponents in the league and CL by a combined 17-8, Leicester’s expected goals difference is just 10.3-9.1. But Leicester has produced more expected goals than its opponents in five of its seven matches after running negative in expected goal difference under Ranieri. It is certainly possible that Leicester will continue performing at this higher level under Shakespeare.However, it is hard to identify any key changes Shakespeare made. Leicester City remains the highest-tempo team in the Premier League, with more possessions per match than anyone else. The Foxes still work best without the ball, managing the same 42 percent possession rate as under Ranieri. What seems to have changed is not Leicester’s style of play, but the effectiveness of it. This is the sort of change, not linked to any obvious tactical shift, that analysts tend to be skeptical of. It might just be form, in which case the large SPI advantage to Atletico Madrid may be correct.For Atletico, this persistent Leicester style may present a problem. Atleti prefers to concede possession and play off the ball, especially against top opponents. But while Atletico is unusual in the Champions League for its roughly 50 percent possession rate, Leicester at 42 percent is more extreme. Atletico will likely need to adjust its typical knockout strategy and make use of ball possession to get past Leicester, even if the Foxes’ current run of form may not be entirely sustainable.Check out our club soccer predictions.
More information: Measuring the Distribution and Excitation of Cometary CH3OH Using ALMA, arXiv:1602.03488 [astro-ph.EP] arxiv.org/abs/1602.03488AbstractThe Atacama Large Millimeter/submillimeter Array (ALMA) was used to obtain measurements of spatially and spectrally resolved CH3OH emission from comet C/2012 K1 (PanSTARRS) on 28-29 June 2014. Detection of 12-14 emission lines of CH3OH on each day permitted the derivation of spatially-resolved rotational temperature profiles (averaged along the line of sight), for the innermost 5000 km of the coma. On each day, the CH3OH distribution was centrally peaked and approximately consistent with spherically symmetric, uniform outflow. The azimuthally-averaged CH3OH rotational temperature (Trot) as a function of sky-projected nucleocentric distance (ρ), fell by about 40 K between ρ=0 and 2500 km on 28 June, whereas on 29 June, Trot fell by about 50 K between ρ=0 km and 1500 km. A remarkable (∼50 K) rise in Trot at ρ=1500-2500 km on 29 June was not present on 28 June. The observed variations in CH3OH rotational temperature are interpreted primarily as a result of variations in the coma kinetic temperature due to adiabatic cooling, and heating through Solar irradiation, but collisional and radiative non-LTE excitation processes also play a role. © 2016 Phys.org 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: Scientists measure methyl alcohol emission from comet C/2012 K1 (PanSTARRS) (2016, February 22) retrieved 18 August 2019 from https://phys.org/news/2016-02-scientists-methyl-alcohol-emission-comet.html ALMA confirms comets forge organic molecules in their dusty atmospheres Explore further For their measurements, the researchers employed the Atacama Large Millimeter/submillimeter Array (ALMA), located in the Atacama desert, Chile. ALMA, thanks to its unprecedented resolution and sensitivity, was previously used to study the distributions of HCN (hydrogen cyanide), HNC (hydrogen isocyanide) and H2CO (formaldehyde) in the inner comae of comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON). Now, the facility obtained new information on the distribution and temperature of methanol in the inner coma of comet C/2012 K1 (PanSTARRS). The observations were conducted on June 28-29, 2014, when the comet was very bright (magnitude 8.5), visible through a small telescope and even binoculars, and relatively near Earth at a distance of nearly two astronomical units (AU).”ALMA was used to obtain measurements of spatially and spectrally resolved CH3OH emission from comet C/2012 K1 (PanSTARRS). (…) Detection of 12-14 emission lines of CH3OH on each day permitted the derivation of spatially-resolved rotational temperature profiles (averaged along the line of sight), for the innermost 5,000 km of the coma,” the scientists wrote in a research paper.C/2012 K1 (PanSTARRS) is an Oort cloud comet that was discovered on May 17, 2012 using the Pan-STARRS telescope located on the island of Maui in Hawaii. The comet came to perihelion on Aug. 27, 2014 at a distance of 1.05 AU from the sun. Thus, the summer of 2014 offered astronomers a great chance to observe this icy planetesimal in detail.Comets are believed to be frozen leftovers from the formation of the solar system around 4.5 billion years ago. They are relatively pristine and therefore may hold clues to how the solar system was made. Finding an organic compound like methanol on a comet hints that these icy bodies could have been a source of the complex organic molecules necessary for life.Methanol, thanks to its abundance in comets and its complex energy level structure is an easily detectable molecule for probing the cometary coma temperature at radio and submillimeter wavelengths. ALMA observations of methanol emission at millimeter and submillimeter wavelengths have permitted Cordiner’s team to conduct the first instantaneous, spatially resolved 2-D measurements of the coma’s rotational temperatures. They detected large variations in the methanol rotational temperature in C/2012 K1 (PanSTARRS) over distances of about 1,000 kilometers (sky-projected distance), likely caused by changes in the coma kinetic temperature, mainly due to adiabatic cooling, and heating through solar irradiation.”This study demonstrates that spatial temperature variations may need to be considered when deriving coma molecular abundances from spectral line data,” the researchers concluded.The scientists called for further high resolution observations and modelling that could yield better information about the coma thermal physics and molecular excitation, and assist in more accurate determination of cometary compositions. They also also emphasized that there is still a lack of understanding concerning the physical and chemical structure of the near-nucleus cometary coma at distances less than a few thousand kilometers from the nucleus. (Phys.org)—An international team of researchers led by Martin Cordiner of NASA’s Goddard Space Flight Center has conducted measurements of CH3OH (methanol) emission from comet C/2012 K1 (PanSTARRS) that could yield invaluable information about cometary compositions and provide insights on the formation of our solar system. The results were published online on Feb. 16 in the arXiv journal. NEOWISE series of infrared images of comet C/2012 K1 (PanSTARRS) on May 20, 2014. Credit: NASA/JPL