February 27, 2017 An image of the Taurus Molecular Cloud, about 450 light-years from Earth. Many carbon-chain molecules have been detected towards dark clouds like these, but astronomers have sought HC11N without success. They speculate that chains this large preferentially transform into carbon rings. Credit: ESO; Digitized Sky Survey; Davide De Martin

The interstellar medium of the Milky Way contains 5-10% of the total mass of the galaxy (excluding its dark matter) and consists primarily of hydrogen gas. There are small but important contributions from other gases as well, including carbon-bearing molecules both simple, like carbon monoxide and carbon dioxide, and complex like ethene, benzene, propynal, methanol and other alcohols, and cyanides. There are even some very large molecules like polycyclic aromatic hydrocarbons and buckyballs with fifty or more carbon atoms. Some species like the cyanides have relative abundances similar to what is seen in comets in our solar system, suggesting that local carbon chemistry is not unique.

Astronomers think complex interstellar molecules are probably produced on dust grains, although some molecules might be produced in the gas phase. About one percent by mass of the interstellar material, these tiny grains are composed predominantly of silicates and provide the gas molecules with surfaces on which to react with other molecules. Carbon chain molecules are particularly interesting because they are thought to be the starting point for a significant fraction of the known complex chemicals in the interstellar medium. It is even suspected that carbon-chain species are a key stage in the formation of polycyclic aromatic hydrocarbons. Carbon-chain molecular chemistry thus provides insight into a large subset of interstellar chemistry.

A particularly well-studied family of carbon chains is the cyanopolyynes: linear molecules of the form HCnN, where n = 3, 5, 7, 9, etc. They have been observed in high abundance towards older stars and in cold dark clouds. The presence of the largest known cyanopolyyne, HC11N, however, is in dispute. It was reportedly detected in 1982 towards one dark cloud in Taurus, but that detection has not been confirmed. CfA astronomers Ryan Loomis and Brett McGuire and their colleagues used the Green Bank Telescope to search the Taurus region for HC11N in six of its characteristic radio wavelength transitions, including the two in which it was first reported, but without success.

The astronomers argue that the previous detection was an error, and they offer an explanation for the otherwise curious absence of the n=11 species. Laboratory experiments have shown that when carbon-chain molecules get to be longer than about n=9 they begin to curl on themselves and preferentially transform into carbon-ring molecules, which are more stable. A similar process could be occurring in the interstellar medium, siphoning away HC11N to form cyclic species. The non-detection of HC11N thus suggests the importance of this chemical pathway in producing cyclic molecules, although the authors note that further observations and laboratory experiments are needed to confirm the model.

Explore further: The formation of carbon-rich molecules in space

More information: Ryan A. Loomis et al. Non-detection of HCN towards TMC-1: constraining the chemistry of large carbon-chain molecules, Monthly Notices of the Royal Astronomical Society (2016). DOI: 10.1093/mnras/stw2302

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Constraining the chemistry of carbon-chain molecules in space - Phys.Org

TAMPA Lets start by dispelling one misperception: Goose Gossage does not spend spring training chasing kids off his lawn.

The Hall of Fame closer, a Yankees guest instructor, smiles and jokes his way through his time George M. Steinbrenner Field. He befriends anyone and everyone whose path he crosses. That he sounds like a troglodyte in interviews has no bearing on his actual behavior.

Now lets blow up one misperception championed by Goose himself: Baseball is not, as he put it recently to NJ.com, being run by a computer.

Actually, in accordance with the dramatic evolution of statistical analysis, mastery of a players intangible and unquantifiable qualities may be more important than ever. Old-school detective work and, really, guesswork remain prominent as front offices try to determine not only a players value on the field, but also his assets and liabilities in the clubhouse.

I do believe that especially if youre in a large market and you bring aboard someone that is a massive problem, that has a lot of issues those issues become everybodys issues, and they do drain on you, Yankees general manager Brian Cashman said. They drain on the collective over the course of spring training and the 162-game regular season. Your teammates problems become your problems, which becomes an issue, a distraction and a fatigue factor thats going to come with it.

I do think that prevents you from being the best you overall can be. I believe in that. Whereas 20 years ago, you can bring anybody in and survive that. Now I dont think its as easy with social media, TMZ and stuff like that. Because youre too busy instead of talking about the game and the results and the competition, youre too busy talking about something thats going on off the field or not game-related constantly. Its a pain. Its a problem.

It is, be it positive or negative, real. Some analytics enthusiasts have attempted to conflate the rise of the drastically improved measures with the pooh-poohing of concepts like chemistry and culture. The new generation of front-office executives, these enthusiasts profess, worry only about the concrete.

Nope. You wont find a GM, no matter how analytically inclined, who doesnt possess a strong interest in how a player interacts with others.

Matt Klentak, who became the Phillies GM in the fall of 2015, still is in his 30s and carries the reputation of a modern thinker. Asked how much he contemplates the personalities of his players, Klentak said, I think its incredibly important, and I think particularly for us, where we stand right now, there are so many young players that are either in the big leagues or on the cusp of making the big leagues. Making sure that those players are entering an environment that is supportive of the growth and the learning that needs to take place, its critical.

In Klentaks second full season running the Phillies, he acquired a bevy of veterans Joaquin Benoit, Clay Buchholz, Howie Kendrick and Michael Saunders on one-year contracts. The group collectively (albeit some more than others) carries a strong reputation as leaders.

That was not an accident, Klentak said.

The methodology to research a players character hasnt undergone anything approaching the sort of transformation weve seen when it comes to a players performance. Nevertheless, some obvious updates have become standard operating procedure. Teams will check out a prospective free agents social-media accounts.

But it doesnt mean that if theyve got a pristine social-media record, then [it will prevent] all of a sudden when you come over here, next thing you know, all hell breaks loose, Cashman said. You try to use everything in your disposal to try to form an opinion, but it doesnt mean the opinion is going to be accurate. Nor does it mean the opinion is going to hold.

The players are scrutinized to a degree weve never seen before in this game, Klentak said. And with that comes accountability. I dont know if that by itself is a bad thing. But I think the way we construct a roster, the way the manager manages a group of 25 men, has to account for all of that.

CC Sabathia, who has started his 17th year of work in a major league clubhouse, sees the upside of such scrutiny.

Everybody just knows who the bad guys are now, he said. Before, it would have to take something to happen. Now, it can be a tweet. It can be anything. Its not a big deal. You root them out faster.

The changes in statistical analysis allow the teams to manage risk like never before.

Youre in a better position to assess what really is taking place on the field, where before it was opinion on something that youre seeing 50 to 75 feet in the stands away, Cashman said. Its someones opinion on how they perceive someones play and action and stuff over the course of a small sample period. Now you have full access to kind of dissect and peel the onion on someone and get a real educated position on what actually that play is and how it projects moving forward.

On the aspect of a players personality, however, the risk hasnt gone away.

You can never predict how someones going to react to big money, Cashman said. Someone whos hungry playing for a year-to-year versus how they act when they get a five-year deal with big-time money. Does it change their interest and effort? Are they going to become content? You cant predict stuff like that.

I think most teams are looking for an edge, however they can get one, Klentak said. And if it comes in the form of elite scouting, or better analytics departments and technologies, or in the form of nutrition or player development were all looking for competitive advantages. If the environment for the players allows them to perform at a higher level, that creates an advantage.

The optimal environment, with an optimal group of 25, represents baseballs final frontier. And it always will require a human touch to be as right as possible.

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