ST. PETERSBURG, Fla. (AP) - Sean Rodriguez turned his extra pregame work into a big offensive performance.
Rodriguez hit a go-ahead two-run homer, helping the Tampa Bay Rays continue their home dominance over the New York Yankees in a 7-4 victory over the AL East leaders on Tuesday night.
Rodriguez, mired in a 17 for 100 slump dating back to May 21, finished with 3 for 4.
"Any night with three hits, and it's always good," Rodriguez said.
Rodriguez has spent the past few days working early with Rays hitting coach Derek Shelton.
"Definitely been more focused on certain things," Rodriguez said. "Positioning in the box. What my mindset is when I get in the box, and what I'm looking for. Having the right approach."
After blowing a three-run lead, New York went ahead 4-3 on Eric Chavez's RBI single during the fourth. Tampa Bay responded in the bottom half and grabbed a 5-4 lead on Rodriguez's first homer since May 27 off Ivan Nova (9-3).
"Great at-bats," Rays manager Joe Maddon said about Rodriguez. "Obviously, the home run was big. Struck the ball well. I'm sure that's going to really bolster his confidence."
James Shields (8-5) gave up four runs and 10 hits over seven innings for the Rays, who have won nine straight at Tropicana Field over the Yankees.
"We've got to find a way to win a game," New York manager Joe Girardi said. "We haven't played well and we've had a lead the last couple of nights, but given it up. We've got to find a way to hold the lead. Tonight wasn't a good game for us. We have to put up a good game tomorrow to win."
Tampa Bay extended its lead to 7-4 with a two-run seventh. After Desmond Jennings stole home on a play that had catcher Russell Martin make a bad throw to second on B.J. Upton's stolen base attempt, Ben Zobrist had a run-scoring single.
Nova, who entered 5-0 in his past seven starts, allowed six runs and seven hits in six-plus innings. The right-hander had won his previous four starts against Tampa Bay.
Fernando Rodney, the Rays' third reliever, pitched the ninth for his 24th save.
New York took a 2-0 lead in the first when Curtis Granderson had an RBI double and Robinson Cano hit a run-scoring single.
Cano, who has driven in at least one run in a career-high seven consecutive games, was then doubled off first on Nick Swisher's one-out fly to center. Cano was also thrown out at the plate on a relay throw from Rodriguez and a nice tag by catcher Jose Molina on Raul Ibanez's sixth-inning double.
"That was a very big moment in tonight's game," Maddon said.
Dewayne Wise made it 3-0 on a third-inning solo homer.
Wise nearly threw out Elliot Johnson out at the plate from left field on Upton's two-out single later in the third, but a sliding Johnson was called safe when Martin juggled the ball during the tag try. Jeff Keppinger then tied it at 3 on a two-run single.
"It's a bad one for me," Martin said. "Offensively I've been pretty bad all year, but defensively, normally, is kind of a salvage, but today was just a bad one overall. I felt like this is pretty much my loss. If I make that play in the third inning, it's a whole different ball game."
Martin, hitting .182, went 0 for 4 and is hitless in his past 23 at-bats.
Yankees first baseman Mark Teixeira was out of the lineup on a planned day off that was set up about a week ago. The break came one day after Teixeira made his first error in 94 games, a misplayed two-out grounder in the seventh inning that allowed the eventual winning run to score in New York's 4-3 loss to Tampa Bay.
Chavez, who took Teixeira's spot, was charged with an error after mishandling Zobrist's grounder in the third.
NOTES: Rays LHP David Price (11-4), who left his previous start last Friday after seven innings because of lower back tightness, will go against Yankees RHP David Phelps (1-3) in Wednesday's series finale. Phelps is filling for New York ace CC Sabathia, who has been out since straining his left groin on June 24. ... Sabathia threw in the outfield for the second consecutive game, including at 60 feet. The left-hander expects to have a mound session this weekend. ... Tampa Bay OF Matt Joyce (strained left oblique) is set to join Triple-A Durham and will have his status evaluated after playing Thursday.
? 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
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What a blast! White Sox cruise
Kevin Youkilis, Adam Dunn and Alex Rios homered in the first inning off Roy Oswalt and All-Star Chris Sale won his 10th game Tuesday night and the Chicago White Sox routed the Texas Rangers 19-2.
Chipper's 1st 5-hit game in decade lifts Braves
ATLANTA (AP) - Newly chosen All-Star Chipper Jones delivered his first five-hit game in a decade, driving in four runs Tuesday night and leading the Atlanta Braves over the Chicago Cubs 10-3.
What does a justice turn to at moments like this? Some say ideology, and they do so derisively, as though cases are nothing but a left-right political tug-of-war. But when all is said and done, law inevitably reflects ideological beliefs. How could one think otherwise? In a deep way this case was about liberty, government power, and states? rights?issues about which the justices have strong visceral feelings, even if those issues were not front and center in the briefs and arguments.
All WWE programming, talent names, images, likenesses, slogans, wrestling moves, trademarks, logos and copyrights are the exclusive property of WWE, Inc. and its subsidiaries. All other trademarks, logos and copyrights are the property of their respective owners. ? 2012 WWE, Inc. All Rights Reserved. This website is based in the United States. By submitting personal information to this website you consent to your information being maintained in the U.S., subject to applicable U.S. laws. U.S. law may be different than the law of your home country. WrestleMania XXIX (NY/NJ) logo TM & ? 2012 WWE. All Rights Reserved. The Empire State Building design is a registered trademark and used with permission by ESBC.
[ [ [['Connery is an experienced stuntman', 2]], 'http://yhoo.it/KeQd0p', '[Slideshow: See photos taken on the way down]', ' ', '630', ' ', ' ', ], [ [['Connery is an experienced stuntman', 7]], ' http://yhoo.it/KpUoHO', '[Slideshow: Death-defying daredevils]', ' ', '630', ' ', ' ', ], [ [['know that we have confidence in', 3]], 'http://yhoo.it/LqYjAX ', '[Related: The Secret Service guide to Cartagena]', ' ', '630', ' ', ' ', ], [ [['We picked up this other dog and', 5]], 'http://yhoo.it/JUSxvi', '[Related: 8 common dog fears, how to calm them]', ' ', '630', ' ', ' ', ], [ [['accused of running a fake hepatitis B', 5]], 'http://bit.ly/JnoJYN', '[Related: Did WH share raid details with filmmakers?]', ' ', '630', ' ', ' ', ], [ [['accused of running a fake hepatitis B', 3]], 'http://bit.ly/KoKiqJ', '[Factbox: AQAP, al-Qaeda in Yemen]', ' ', '630', ' ', ' ', ], [ [['have my contacts on or glasses', 3]], 'http://abcn.ws/KTE5AZ', '[Related: Should the murder charge be dropped?]', ' ', '630', ' ', ' ', ], [ [['have made this nation great as Sarah Palin', 5]], 'http://yhoo.it/JD7nlD', '[Related: Bristol Palin reality show debuts June 19]', ' ', '630', ' ', ' ', ], [ [['have made this nation great as Sarah Palin', 1]], 'http://bit.ly/JRPFRO', '[Related: McCain adviser who vetted Palin weighs in on VP race]', ' ', '630', ' ', ' ', ], [ [['A JetBlue flight from New York to Las Vegas', 3]], 'http://yhoo.it/GV9zpj', '[Related: View photos of the JetBlue plane in Amarillo]', ' ', '630', ' ', ' ', ], [ [['the 28-year-old neighborhood watchman who shot and killed', 15]], 'http://news.yahoo.com/photos/white-house-stays-out-of-teen-s-killing-slideshow/', 'Click image to see more photos', 'http://l.yimg.com/cv/ip/ap/default/120411/martinzimmermen.jpg', '630', ' ', 'AP', ], [ [['He was in shock and still strapped to his seat', 6]], 'http://news.yahoo.com/photos/navy-jet-crashes-in-virginia-slideshow/', 'Click image to see more photos', 'http://l.yimg.com/cv/ip/ap/default/120406/jet_ap.jpg', '630', ' ', 'AP', ], [ [['xxxxxxxxxxxx', 11]], 'http://news.yahoo.com/photos/russian-grannies-win-bid-to-sing-at-eurovision-1331223625-slideshow/', 'Click image to see more photos', 'http://l.yimg.com/a/p/us/news/editorial/1/56/156d92f2760dcd3e75bcd649a8b85fcf.jpeg', '500', ' ', 'AP', ] ]
[ [ [['did not go as far his colleague', 8]], '29438204', '0' ], [ [[' the 28-year-old neighborhood watchman who shot and killed', 4]], '28924649', '0' ], [ [['because I know God protects me', 14], ['Brian Snow was at a nearby credit union', 5]], '28811216', '0' ], [ [['The state news agency RIA-Novosti quoted Rosaviatsiya', 6]], '28805461', '0' ], [ [['measure all but certain to fail in the face of bipartisan', 4]], '28771014', '0' ], [ [['matter what you do in this case', 5]], '28759848', '0' ], [ [['presume laws are constitutional', 7]], '28747556', '0' ], [ [['has destroyed 15 to 25 houses', 7]], '28744868', '0' ], [ [['short answer is yes', 7]], '28746030', '0' ], [ [['opportunity to tell the real story', 7]], '28731764', '0' ], [ [['entirely respectable way to put off the searing constitutional controversy', 7]], '28723797', '0' ], [ [['point of my campaign is that big ideas matter', 9]], '28712293', '0' ], [ [['As the standoff dragged into a second day', 7]], '28687424', '0' ], [ [['French police stepped up the search', 17]], '28667224', '0' ], [ [['Seeking to elevate his candidacy back to a general', 8]], '28660934', '0' ], [ [['The tragic story of Trayvon Martin', 4]], '28647343', '0' ], [ [['Karzai will get a chance soon to express', 8]], '28630306', '0' ], [ [['powerful storms stretching', 8]], '28493546', '0' ], [ [['basic norm that death is private', 6]], '28413590', '0' ], [ [['songwriter also saw a surge in sales for her debut album', 6]], '28413590', '1', 'Watch music videos from Whitney Houston ', 'on Yahoo! Music', 'http://music.yahoo.com' ], [ [['keyword', 99999999999999999999999]], 'videoID', '1', 'overwrite-pre-description', 'overwrite-link-string', 'overwrite-link-url' ] ]
SAFED, Israel (Reuters) - They grow in a secret location in northern Israel. A tall fence, security cameras and an armed guard protect them from criminals. A hint of their sweet-scented blossom carries in the air: rows and rows of cannabis plants, as far as the eye can see.
It is here, at a medical marijuana plantation atop the hills of the Galilee, where researchers say they have developed marijuana that can be used to ease the symptoms of some ailments without getting patients high.
"Sometimes the high is not always what they need. Sometimes it is an unwanted side effect. For some of the people it's not even pleasant," said Zack Klein, head of development at Tikun Olam, the company that developed the plant.
Cannabis has more than 60 constituents called cannabinoids. THC is perhaps the best known of those, less so for its medical benefits and more for its psychoactive properties that give people a "high" feeling.
But cannabis also contains Cannabidiol, or CBD, a substance that some researchers say has anti-inflammatory benefits. Unlike THC, it hardly binds to the brain's receptors and can therefore work without getting patients stoned.
"CBD plants are available in different forms all over the world," said Klein, adding that the company's plant is free of THC and very high in CBD.
Tikun Olam began its research on CBD enhanced cannabis in 2009 and about six months ago they came up with Avidekel, Klein said, a cannabis strain that contains 15.8 percent CBD and only traces of THC, less than one percent.
CANNABIS AS MEDICINE
Marijuana is an illegal drug in Israel. Medicinal use of it was first permitted in 1993, according to the health ministry.
Today cannabis is used in Israel to treat 9,000 people suffering from illnesses such as cancer, Parkinson's, multiple sclerosis, Crohn's disease and post traumatic stress disorder, according to Israel's health ministry.
Drug companies have also been interested in cannabis as a medicine. Britain's GW Pharmaceuticals, with Bayer and Almirall, sells an under-the-tongue spray called Sativex that is designed to minimize highs by manipulating ratios of active ingredients.
Raphael Mechoulam, a professor of medicinal chemistry at the Hebrew University in Jerusalem, said Avidekel is thought to be the first CBD-enriched cannabis plant with no THC to have been developed in Israel.
"It is possible that (Avidekel's) CBD to THC ratio is the highest among medical marijuana companies in the world, but the industry is not very organized, so one cannot keep exact track of what each company is doing," he explained.
Although there have been no clinical trials in humans, Mechoulam, who is a leading researcher of cannabinoids, said that Avidekel showed promise as a potent anti-inflammatory.
Ruth Gallily of the Hebrew University who works for the company and has been studying CBD for more than 12 years, said she has found that the substance has impressive anti-inflammatory qualities. She has been testing the effects of Tikun Olam's CBD-enhanced cannabis on mice and expects clinical trials to begin in a few months.
Avidekel is a new strain of a plant that is already permitted for medical use so there is nothing stopping patients who are already being treated with marijuana from trying Avidekel. About 10 patients began using it in the past six months, Klein said.
"The cannabis plant, enriched with CBD, can be used for treating diseases like rheumatoid arthritis, colitis, liver inflammation, heart disease and diabetes," she said, adding there are no side effects.
"It's a huge advantage," said one 35-year-old patient who asked not to be identified, "I can smoke during the day, function with a lot less pain and still be focused, work and drive. It is a great gift."
The woman began suffering chronic pains after a tumor was removed from her spine. She began treatment with regular THC-containing marijuana eight months ago. Two months ago she started smoking Avidekel.
"The difference is huge. Before, I would only smoke at the end of the day and stay in pain." Now, she said, with the highless marijuana "my life is so much better."
Despite Avidekel's highless benefit, Klein does not see regular marijuana disappearing any time soon. THC has its own unique effects that alleviate illness symptoms.
"Don't worry, I think that cannabis with THC will still be (around)," he said.
ROME (AP) -A thousand fans cheered loudly, applauded and sang the national anthem when Italy coach Cesare Prandelli and his players returned to Rome after having lost the European Championship final.
The squad was first greeted by about 200 workers Monday as they stepped off the plane at Rome's Fiumicino airport before departing on one of the four coaches reserved for the Italian delegation.
"We are still bitterly disappointed, but we know that we had a great European Championship," captain Gianluigi Buffon said of the 4-0 loss to Spain in the final on Sunday. "We played the final against the strongest team and not in the best conditions."
The loudest cheers were reserved for Buffon, Daniele De Rossi, Mario Balotelli, Antonio Cassano and, above all, for Prandelli, who was beaming broadly.
The squad then attended a reception hosted by Italy President Giorgio Napolitano at the presidential palace, with Buffon introducing his teammates one by one.
"Everyone knew the tension you left in and with a team that has just been rebuilt and which still has a long way to go," Napolitano said. "When I say these things people often ask me whether I'm talking about football or Italy, and I have to say they are one and the same.
"I have never played football so I can't judge your efforts, but the passion and spirit you had and the sense of national pride really hit me. It was the best gift you could give me."
Napolitano sent a letter to the Italy players and staff after the semifinal victory over Germany and invited them to a reception, regardless of the result in the final.
"Thank you for the invite because it will help everyone understand that you have to acknowledge the performance above the result," Prandelli said. "We are proud to have represented Italy with those values that you wrote in the letter, which really touched us. After every match the lads asked me if you'd called because you are our No. 1 fan."
Prandelli gave Napolitano his runner-up medal. Andrea Pirlo and Balotelli presented him with an Italy pennant and football.
? 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
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Spain fetes its champions
Swathed in the red-and-yellow colors of Spain, hundreds of thousands packed central Madrid to give a hero's welcome Monday to "La Roja'' - the national soccer team that erased the country's gloomy mood by winning the Euro 2012 Championship with such flair.
Spain has eyes set on going down as greatest team
KIEV, Ukraine (AP) -Spain has taken its place among football's all-time great sides by becoming the first team to defend its European Championship after winning the World Cup. The task, now, is to be remembered as the greatest.
Oh, baby! A young star flaunts its X-ray spots in McNeil's NebulaPublic release date: 3-Jul-2012 [ | E-mail | Share ]
Contact: Susan Gawlowicz smguns@rit.edu 585-475-5061 Rochester Institute of Technology
RIT astronomers on team announcing the rapidly spinning protostar
X-ray observations have revealed something curious about the young star that illuminates McNeil's Nebula, a glowing jewel of cosmic dust in the Orion constellation: The object is a protostar rotating once a day, or 30 times faster than the sun. The stellar baby also has distinct birthmarkstwo X-ray-emitting spots, where gas flows from a surrounding disk, fueling the infant star.
The young star, V1647 Orionis, first made news in early 2004, when it erupted and lit up McNeil's Nebula, located 1,300 light years away in a region of active star formation within the constellation of Orion. The initial outburst died down in early 2006, but then V1647 Ori erupted again in 2008, and has since remained bright.
More recently, astronomers combined 11 observations of V1647 Ori from NASA's Chandra X-ray Observatory, the Japan-led Suzaku satellite, and the European Space Agency's XMM-Newton to determine the source of the high-energy emission. The team began monitoring the star shortly after its eruption in 2004 and continued to keep watch through 2010, a period covering both eruptions.
Strong similarities among X-ray light curves captured over this six-year period allowed the lead author on the study, Kenji Hamaguchi, astrophysicist at NASA's Goddard Space Flight Center, to identify cyclic X-ray variations. Hamaguchi and the rest of the team determined the star is rotating once per day, making V1647 among the youngest stars whose spin has been determined using an X-ray-based technique. Results from the study will appear in the paper "X-raying the Beating Heart of a Newborn Star: Rotational Modulation of High-energy Radiation from V1647 Ori," in the July 20 issue of The Astrophysical Journal.
"The observations give us a look inside the cradle at a very young star," says co-author Joel Kastner, a professor of imaging science and astronomical sciences and technology at Rochester Institute of Technology. "It's as though we're able to see its beating heart. We're actually able to watch it rotate. We caught the star at a point where it is rotating so fast as it gains material that it's barely able to hold itself together. It's rotating at near break-up speed."
The team identified V1647 Ori as a protostar in formation. "Based on infrared studies, we suspect that this protostar is no more than a million years old, and probably much younger," Hamaguchi says.
V1647 Ori presently feeds on gas channeled from a surrounding disk and will likely continue to do sothough not nearly so rapidlyfor millions of years. At that point it will finally be able to generate its own energy by fusing hydrogen into helium in its core like the sun and other mature stars.
Hamaguchi's analysis focused on repetitive behavior found in the data from all three of the X-ray observatories. By combining data, he pieced together a picture showing the daily rotation of two X-ray-emitting spots on V1647 Ori that are thousands of times hotter than the rest of the star.
The hot spots are located at opposite sides of the star, with the southerly one five times brighter than its companion. Each spot is about the diameter of the sun. In comparison, the low density of V1647 Ori bloats the star itself to nearly five times the size of the sun.
"We think these spots are showing us X-ray-emitting regions that are very tightly constrained to a couple positions on the star by magnetic fields," says Kastner, director of the Laboratory for Multiwavelength Astrophysics in RIT's Chester F. Carlson Center for Imaging Science. "For six years, through two different eruptions, we've seen it rotate like this. That means the magnetic field configurationthe overall geometry between the disk and the staris very stable. At the same time, the local disruption of magnetic fields probably generates the X-rays."
"One attractive possibility for driving such high-speed matter involves magnetic fields that are undergoing a continual cycle of shearing and reconnection in mass accretion," says co-author David Weintraub, professor of astronomy at Vanderbilt University.
In this picture, X-ray outbursts result from interplay of the magnetic fields belonging to the star and the disk. The star spins faster than the disk and winds up the magnetic fields until they snap like rubber bands. The pent up energy creates a powerful blast when the tangled magnetic fields fall back into place. The process, called magnetic reconnection, also powers X-ray flares on the sun.
During the outbursts, the star's luminosity varied at optical and infrared wavelengths. The astronomers associated this to changes in the protostar's main energy source, the inflow of matter onto the star. Because changes in the X-ray brightness of V1647 Ori closely followed those in the optical and infrared, the team established that its higher-energy emission is also closely linked to accretion.
"V1647 Ori gave us the first direct evidence that a protostar surges in X-ray activity as its rate of mass accretion rises," says co-author Nicolas Grosso, an astrophysicist of the French National Center for Scientific Research at the Strasbourg Astronomical Observatory.
The finding that an accretion burst could be accompanied a surge of high-energy X-rays during the formation of a young star was originally announced by essentially the same study team, led by Kastner, in a paper published in Nature in 2004. In that paper, the team first argued that X-rays emitted by V1647 Ori were coming from material falling onto the star from a surrounding disk.
Up until then, the more widely accepted mechanism for producing X-rays from protostars was thought to be via coronae that are far more powerful than the sun's, Kastner explains. Signatures in X-ray observations of a handful of stars in formative stages had led to the hunch that accretion might also contribute to or even dominate protostellar X-ray emission. The eruptions of V1647 Ori and a few other young stars that were accompanied by elevated X-ray emission levels have since underscored this connection, Kastner notes.
"The exciting and unexpected thing about our fresh look at the whole set of X-ray data for V1647 Ori is that this is the first time we've seen a star in such an early stage of formation with a regular rotation that you can measure in X-rays," Kastner says.
Kastner and team hope to confirm the X-ray study's findings at infrared wavelengths using NASA's Spitzer Space Telescope.
###
Additional co-authors on the study include Michael Richmond, professor of physics at RIT; David Principe, a doctoral candidate in RIT's Astrophysical Sciences and Technology program; and William Teets, a recent doctoral recipient in physics and astronomy from Vanderbilt University.
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Oh, baby! A young star flaunts its X-ray spots in McNeil's NebulaPublic release date: 3-Jul-2012 [ | E-mail | Share ]
Contact: Susan Gawlowicz smguns@rit.edu 585-475-5061 Rochester Institute of Technology
RIT astronomers on team announcing the rapidly spinning protostar
X-ray observations have revealed something curious about the young star that illuminates McNeil's Nebula, a glowing jewel of cosmic dust in the Orion constellation: The object is a protostar rotating once a day, or 30 times faster than the sun. The stellar baby also has distinct birthmarkstwo X-ray-emitting spots, where gas flows from a surrounding disk, fueling the infant star.
The young star, V1647 Orionis, first made news in early 2004, when it erupted and lit up McNeil's Nebula, located 1,300 light years away in a region of active star formation within the constellation of Orion. The initial outburst died down in early 2006, but then V1647 Ori erupted again in 2008, and has since remained bright.
More recently, astronomers combined 11 observations of V1647 Ori from NASA's Chandra X-ray Observatory, the Japan-led Suzaku satellite, and the European Space Agency's XMM-Newton to determine the source of the high-energy emission. The team began monitoring the star shortly after its eruption in 2004 and continued to keep watch through 2010, a period covering both eruptions.
Strong similarities among X-ray light curves captured over this six-year period allowed the lead author on the study, Kenji Hamaguchi, astrophysicist at NASA's Goddard Space Flight Center, to identify cyclic X-ray variations. Hamaguchi and the rest of the team determined the star is rotating once per day, making V1647 among the youngest stars whose spin has been determined using an X-ray-based technique. Results from the study will appear in the paper "X-raying the Beating Heart of a Newborn Star: Rotational Modulation of High-energy Radiation from V1647 Ori," in the July 20 issue of The Astrophysical Journal.
"The observations give us a look inside the cradle at a very young star," says co-author Joel Kastner, a professor of imaging science and astronomical sciences and technology at Rochester Institute of Technology. "It's as though we're able to see its beating heart. We're actually able to watch it rotate. We caught the star at a point where it is rotating so fast as it gains material that it's barely able to hold itself together. It's rotating at near break-up speed."
The team identified V1647 Ori as a protostar in formation. "Based on infrared studies, we suspect that this protostar is no more than a million years old, and probably much younger," Hamaguchi says.
V1647 Ori presently feeds on gas channeled from a surrounding disk and will likely continue to do sothough not nearly so rapidlyfor millions of years. At that point it will finally be able to generate its own energy by fusing hydrogen into helium in its core like the sun and other mature stars.
Hamaguchi's analysis focused on repetitive behavior found in the data from all three of the X-ray observatories. By combining data, he pieced together a picture showing the daily rotation of two X-ray-emitting spots on V1647 Ori that are thousands of times hotter than the rest of the star.
The hot spots are located at opposite sides of the star, with the southerly one five times brighter than its companion. Each spot is about the diameter of the sun. In comparison, the low density of V1647 Ori bloats the star itself to nearly five times the size of the sun.
"We think these spots are showing us X-ray-emitting regions that are very tightly constrained to a couple positions on the star by magnetic fields," says Kastner, director of the Laboratory for Multiwavelength Astrophysics in RIT's Chester F. Carlson Center for Imaging Science. "For six years, through two different eruptions, we've seen it rotate like this. That means the magnetic field configurationthe overall geometry between the disk and the staris very stable. At the same time, the local disruption of magnetic fields probably generates the X-rays."
"One attractive possibility for driving such high-speed matter involves magnetic fields that are undergoing a continual cycle of shearing and reconnection in mass accretion," says co-author David Weintraub, professor of astronomy at Vanderbilt University.
In this picture, X-ray outbursts result from interplay of the magnetic fields belonging to the star and the disk. The star spins faster than the disk and winds up the magnetic fields until they snap like rubber bands. The pent up energy creates a powerful blast when the tangled magnetic fields fall back into place. The process, called magnetic reconnection, also powers X-ray flares on the sun.
During the outbursts, the star's luminosity varied at optical and infrared wavelengths. The astronomers associated this to changes in the protostar's main energy source, the inflow of matter onto the star. Because changes in the X-ray brightness of V1647 Ori closely followed those in the optical and infrared, the team established that its higher-energy emission is also closely linked to accretion.
"V1647 Ori gave us the first direct evidence that a protostar surges in X-ray activity as its rate of mass accretion rises," says co-author Nicolas Grosso, an astrophysicist of the French National Center for Scientific Research at the Strasbourg Astronomical Observatory.
The finding that an accretion burst could be accompanied a surge of high-energy X-rays during the formation of a young star was originally announced by essentially the same study team, led by Kastner, in a paper published in Nature in 2004. In that paper, the team first argued that X-rays emitted by V1647 Ori were coming from material falling onto the star from a surrounding disk.
Up until then, the more widely accepted mechanism for producing X-rays from protostars was thought to be via coronae that are far more powerful than the sun's, Kastner explains. Signatures in X-ray observations of a handful of stars in formative stages had led to the hunch that accretion might also contribute to or even dominate protostellar X-ray emission. The eruptions of V1647 Ori and a few other young stars that were accompanied by elevated X-ray emission levels have since underscored this connection, Kastner notes.
"The exciting and unexpected thing about our fresh look at the whole set of X-ray data for V1647 Ori is that this is the first time we've seen a star in such an early stage of formation with a regular rotation that you can measure in X-rays," Kastner says.
Kastner and team hope to confirm the X-ray study's findings at infrared wavelengths using NASA's Spitzer Space Telescope.
###
Additional co-authors on the study include Michael Richmond, professor of physics at RIT; David Principe, a doctoral candidate in RIT's Astrophysical Sciences and Technology program; and William Teets, a recent doctoral recipient in physics and astronomy from Vanderbilt University.
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Public release date: 3-Jul-2012
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