UCF Physics

Category Archives: 2008

UCF Physics Professor Experiments in Zero Gravity

Date: Friday Jan. 23rd, 2009

Figuring out exactly how asteroids formed and what they can tell us about the origin of the solar system are big questions.

University of Central Florida Assistant Professor Josh Colwell is working on solving these mysteries. This month, he had a chance to conduct experiments that may help in the quest, while floating in zero gravity.

Colwell was one of several educators on a Zero G flight out of Brevard County on Dec. 7. Zero Gravity Corporation is a privately held space entertainment and tourism company, according to the company Web site. It is headquartered in Las Vegas and is the first and only FAA-approved provider of commercial weightless flights for the general public.

Participants are loaded into a specially modified Boeing 727, which performs parabolic flight maneuver that achieves weightlessness. Specially trained pilots fly these maneuvers between approximately 24,000 and 34,000 feet altitude. Each parabola takes 10 miles of airspace to perform and lasts approximately one minute from start to finish, according to the company.

Colwell used a modified version of an experiment he has flown on previous flights. For this one, he adapted the experiment at UCF to be operated while floating freely instead of attached to the airplane floor. The experiment consists of videotaping a projectile impacting a target composed of sand at speeds too low to achieve in normal gravity. Then he will study the amount and speed of material knocked off in the impact. The results are important to understand how the precursors to planets formed from colliding dust particles.

“Weightlessness is an amazing experience,” Colwell said. “Objects don’t behave the way we intuitively expect them to, and that’s part of what makes it such a valuable and unique environment for the kinds of experiments I’m doing.”

The microgravity flight was part of Space Florida’s teacher education program that included 30 teachers.

UCF Announces Planetary Sciences track in Physics PhD

Date: Friday Jan. 23rd, 2009

Starting in Spring 2009, the Physics PhD has a Planetary Sciences
Track.

Introduction: The University of Central Florida has rapidly grown to become a center for research and teaching in the planetary sciences. Our goal is to create a vibrant planetary science research environment that can attract top students, researchers, and faculty and contribute significantly to the exploration of space. The Planetary Sciences Graduate Ph.D. and Masters Tracks are designed to prepare students to be competitive in the global planetary sciences research community.

Admission to the Planetary Science Track: Students must be specifically admitted to the Graduate Planetary Sciences track, either for Masters or Ph.D.. External applications and petitions to switch from the existing Physics graduate program are considered by the Planetary Graduate Committee. Admission to the track requires a Bachelor of Science or equivalent, typically in physics, astronomy, geology, geophysics, geochemistry, atmospheric sciences, or planetary sciences. Those without full academic preparation in physics and astronomy, or low scores on the Departmental placement test may be required to complete specified coursework in addition to the core program, as determined by the Planetary Graduate Committee at the time of admission or their Supervisory Committee at a later date. Petitions to switch from the existing Physics graduate program shall be in the form of a letter to the Planetary Science Graduate Committee addressed to Dr. Dan Britt. The letter should include the request to join the planetary sciences track, the students degree goal (Masters or Ph.D.), the name of the students planetary sciences advisor, and a brief description of their expected area of research.

For more information please click here.

Source of Geysers on Saturn’s Moon May Be Underground Water

Date: Monday Dec. 01st, 2008

Saturn’s moon Enceladus may indeed hide an underground reservoir of water.

Scientists at Jet Propulsion Lab in California, the University of Colorado and the University of Central Florida in Orlando teamed up to analyze the plumes of water vapor and ice particles spewing from the moon. They used data collected by the Cassini spacecraft’s Ultraviolet Imaging Spectrograph (UVIS). Cassini was launched from the Kennedy Space Center in 1997 and has been orbiting Saturn since July 2004.

The team, including UCF Assistant Professor Joshua Colwell, found that the source of plumes may be vents on the moon that channel water vapor from a warm, probably liquid source to the surface at supersonic speeds.

The team’s findings are reported in the Nov. 27 issue of the journal Nature.

“There are only three places in the solar system we know or suspect to have liquid water near the surface,” Colwell said. “Earth, Jupiter’s moon Europa and now Saturn’s Enceladus. Water is a basic ingredient for life, and there are certainly implications there. If we find that the tidal heating that we believe causes these geysers is a common planetary systems phenomenon, then it gets really interesting.”

The team’s findings support a theory that the plumes observed are caused by a water source deep inside Enceladus. This is not a foreign concept. On earth, liquid water exists beneath ice at Lake Vostok, Antarctica.

Scientists suggest that in Enceladus’s case, the ice grains would condense from the vapor escaping from the water source and stream through the cracks in the ice crust before heading into space. That’s likely what Cassini’s instruments detected in 2005 and 2007, the basis for the team’s investigation.

The team’s work also suggests that another hypothesis is unlikely. That theory predicts that the plumes of gas and dust observed are caused by evaporation of volatile ice freshly exposed to space when Saturn’s tidal forces open vents in the south pole. But the team found more water vapor coming from the vents in 2007 at a time when the theory predicted there should have been less.

“Our observations do not agree with the predicted timing of the faults opening and closing due to tidal tension and compression,” said Candice Hansen, the lead author on the project. “We don’t rule it out entirely . . . but we also definitely do not substantiate this hypothesis.”

Instead, their results suggest that the behavior of the geysers supports a mathematical model that treats the vents as nozzles that channel water vapor from a liquid reservoir to the surface of the moon. By observing the flickering light of a star as the geysers blocked it out, the team found that the water vapor forms narrow jets. The authors theorize that only high temperatures close to the melting point of water ice could account for the high speed of the water vapor jets.

Although there is no solid conclusion yet, there may be one soon. Enceladus is a prime target of Cassini during its extended Equinox Mission, underway now through September 2010.

The team of researchers also includes Brad Wallis, and Amanda Hendrix from Jet Propulsion Laboratory; Larry Esposito (principal investigator of the UVIS investigation), Bonnie Meinke and Kris Larsen from the University of Colorado; Wayne Pryor from Central Arizona College; and Feng Tian, from NASA’s postdoctoral program.

“We still have a lot to discover and learn about how this all works on Enceladus,” Colwell said. “But this is a good step in figuring it all out.”

UCF Fulbright Scholars

Date: Monday Nov. 17th, 2008

Five University of Central Florida professors – tied for the most among Florida universities — will travel abroad this year on Fulbright Scholar grants, the flagship cultural education exchange program sponsored by the U.S. Department of State.

UCF is tied with the University of South Florida for having the most Fulbright Scholars of any university in Florida.

While abroad, UCF professors will work to enhance teacher education in Kenya, study near-earth asteroids in Spain, examine the impact of information technology on Austrian organizations and more.

Recipients of Fulbright awards are selected based on their academic and professional achievements and leadership potential in their fields. Fulbright grants give scholars opportunities to observe other countries’ political, economic, educational and cultural institutions and to exchange ideas with scholars in those countries.

“The Fulbright Program’s recognition of five of our faculty and staff members, all from different colleges, is a testament to the outstanding teaching and research at UCF,” said Provost and Executive Vice President Terry Hickey. “The program provides our faculty and staff with exceptional opportunities to share their expertise with leaders in other countries and to return to UCF with new ideas that they can apply in their classrooms and labs.”

The awards are the latest of many top honors received this year by UCF faculty, who have earned eight prestigious National Science Foundation awards that recognize the nation’s most outstanding and promising young scientists and engineers, three of the highest awards bestowed by the world’s premier scientific society in optics and photonics and many more.

The Fulbright Program, which operates in 155 countries, is sponsored by the Department of State’s Bureau of Educational and Cultural Affairs.

UCF faculty and staff who are traveling abroad on Fulbright Scholar grants this year on behalf of the College of Sciences:

– Humberto Campins, professor, Department of Physics; research in Tenerife, Spain; “Low Perihelion Near-Earth Asteroids.”

In addition, one faculty members from foreign universities were selected to conduct research at UCF this year under the Fulbright Scholar Program’s Visiting Grantee program.

– Zeinab Sayed Ibrahim Mansour, assistant professor, Department of Mathematics, Cairo University, Egypt; “Q-Difference and Fractional Equations and Their Solutions.”

For more information on the Fulbright Scholar programs, go to www.fulbright.state.gov.

NASA Tool Helps Track Whale Sharks, Polar Bears

Date: Wednesday Oct. 01st, 2008

Photos of giant whale sharks snapped by vacationing scuba divers and snorkelers are helping scientists track the elusive marine creatures across the oceans.

And the same technique may soon also help researchers track polar bears in Canada, giant Eurasian trout in Mongolia, and ocean sunfish in the Galápagos Islands.

Biologists have adapted a complex algorithm developed by scientists working for NASA. The original algorithm mapped stars. The new one analyzes photos of whale sharks, identifying each animal’s unique pattern of white spots. The program determines if a particular shark has been seen before by other database users.

The participatory tracking technique is already lending new insight into the biology of whale sharks, according to Brad Norman, a research scientist from Murdoch University in Perth, Australia.

The tourist-collected tracking information is helping researchers learn more about where and when the fish migrate and their rate of return to particular areas, Norman said.

For example, at Ningaloo Marine Park in Western Australia, where the tracking technique was first tested, researchers found some sharks remain near the reef for up to three months.

And the global database of whale shark pictures indicates that some of the giant fish migrate between Mexico, Honduras, and Belize.

“We can use these data to highlight the need for international agreements to protect this threatened species,” said Norman, who is a National Geographic Society emerging explorer, as well as the recipient of funding from the Rolex Awards for Enterprise.

(National Geographic News is owned by the National Geographic Society.)

Tracking Whales and Stars

Whale sharks are the world’s largest living fish species, growing more than 40 feet (12 meters) long. They are listed as vulnerable to extinction by the World Conservation Union (IUCN), though little is known about their basic biology, ecology, breeding and migration patterns, and worldwide population size.

In 2000, Norman formed ECOCEAN, a nonprofit marine conservation organization based in Perth, to develop the participatory tracking system to facilitate whale shark studies.

click here to read the entire article.

The Search for Better Catalysts

Date: Tuesday Sep. 23rd, 2008

In recent years, economic, social, and environmental concerns have led to increased interest in alternative sources of energy that do not rely on fossil fuels. One of the most promising technologies in this area is the use of fuel cells for both stationary and mobile energy generation. Alcohols such as methanol (MeOH) have been proposed as potential H2 carriers, as they can be transported using current infrastructures and can be catalytically decomposed on-site to generate the necessary hydrogen gas to feed the fuel cells.

With the support of an award from the ACS-Petroleum Research Fund, Prof. Beatriz Roldán Cuenya and her research team at the University of Central Florida are focusing on the design and evaluation of novel nanoscale catalysts for methanol decomposition. “Our group is trying to improve the catalysts,” explains Roldán Cuenya, “that make it possible to decompose methanol and obtain hydrogen. We’re using platinum nanoparticles as catalysts, and evaluating the many factors that control the level of activity, as well as the selectivity, towards hydrogen production.”

Finding results at the smallest level

Roldán Cuenya’s team is conducting basic investigations on the role of the nanoparticle size and nanoparticle-support interactions on their chemical reactivity and stability. The researchers synthesized size- and shape-selected platinum (Pt) nanoparticles (4, 6, and 8 nm) using the process of inverse micelle encapsulation, and deposited the nanoparticles on titanium dioxide (TiO2) [1]. They then used a packed-bed mass flow reactor and mass spectrometry to quantify the activity and selectivity of these catalysts for MeOH decomposition.

One area of particular interest for Roldán Cuenya’s group is in controlling the production of “poisoning” byproducts, which can form carbon deposits on top of the catalyst particles and prevent further reaction with methanol molecules. “Through our research,” Roldán Cuenya observes, “we’re working to improve the catalyst so that this effect is minimized, and we can produce mainly hydrogen, and not other unwanted, or hydrogen competitive, byproducts such as methane and other gases.”

Among the catalysts tested, the smallest Pt nanoparticles (~4 nm) showed the best performance, including the lowest onset reaction temperature of ~145° C. For a common support (TiO2), the increase in activity with decreasing particle size is attributed to the high number of low-coordinated sites (steps and kinks) that appear, in increasing numbers, as the dimensions of the nanoparticles are reduced.

In a second study, the researchers deposited similarly-sized Pt nanoparticles on a series of reducible/non-reducible, nanocrystalline, metal-oxide supports (CeO2, TiO2, SiO2, ZrO2, and Al2O3) [2]. The nanoparticles deposited on ZrO2 were found to be cationic, and the most active for the decomposition of MeOH. The role of the support was found to be that of a stabilizer, a provider of preferential/additional sites of interaction, and a mediator among the different oxidation states of Pt.

The team’s work with catalysts could have implications for many areas of manufacturing, as well as energy generation and pollution control. “We expect,” says Roldán Cuenya, “that advances in this field may have widespread positive consequences by decreasing the energy input required as well as the yield of potentially harmful byproducts associated with chemical synthesis processes.”

UCF Student to Study Smithsonian’s Meteorite Collection This Summer

Date: Thursday Sep. 11th, 2008

Robert Macke, a UCF student pursuing a Ph.D. in Physics, has won a Smithsonian Institution Graduate Student Fellowship award and will research meteorites this summer at the National Museum of Natural History in Washington, D.C.

During the 10-week program, Macke will measure the density, porosity and magnetic susceptibility of the Smithsonian’s extensive meteorite collection. Meteorites are remnants of asteroids that have been traveling through space and landed on earth.

By studying meteorites, Macke and his Smithsonian colleagues hope to discover vital clues as to how our solar system was formed.

Offered through the Smithsonian’s Office of Research and Training Services, the fellowship allows graduate students to conduct research at the Smithsonian’s facilities alongside Smithsonian research staff members. Each student also receives a $5,500 stipend.

As part of an Air Force family, Macke moved a lot as a child but considers St. Louis his hometown. Growing up, he always had an interest in planetary sciences. “My universe has always been larger than planet Earth, and I have always wanted to know more about it,” he said.

After graduating from the Massachusetts Institute of Technology with a bachelor’s degree in Physics, Macke continued his studies at Washington University in St. Louis. However, he abandoned the Ph.D. degree he was pursuing to become a Jesuit brother and began studying Philosophy at St. Louis University as part of his Jesuit training.

The Jesuits, or Society of Jesus, are a religious order within the Catholic Church. Jesuits are active in education, and they take vows of poverty, chastity and obedience.

“It was, for me, a good way to integrate aspects of life, such as work and prayer, that I had felt until that time were operating in two separate realms,” said Macke, who lives in Tampa with his Jesuit brothers.

Through a connection with one of his Jesuit brothers, Macke was given the opportunity to study the meteorite collection at the Vatican Observatory in Italy. While working there, he met Dan Britt, director of UCF’s Robinson Observatory and a former Smithsonian Fellowship winner.

“Bob is very intense, hard-working, independent and focused on the scientific task — a great student to work with,” said Britt, an associate professor of Physics.

Britt said having access to one of the world’s premier meteorite collections and working with some of the best meteorite scientists will be “a big plus” for Macke.

Macke came to UCF after an invitation from Britt, who now serves as his thesis advisor. He specializes in the physical properties of meteorites.

“Coming to know the planetary science program at UCF, I now see it as ‘getting in on the ground floor’ of something that has the potential to grow into a premier program in the planetary sciences,” Macke said. “It has already attracted some movers and shakers in the field, and before long UCF will be a well-recognized name in planetary sciences.”

In an effort to continue his research by visiting major meteorite collections, Macke applied for the Smithsonian Institution’s Graduate Student Fellowship.

Macke said hopes to learn a lot about the meteorites from the Smithsonian curators and that the fellowship will help him reach out to other curators whose collections he hopes to study someday.

In the future, Macke may continue his work at the Vatican Observatory. He would also like to teach, write books, and find ways to improve science education, especially for underprivileged students.

UCF Scientists study cattle ranching’s role in wetlands

Date: Monday Apr. 21st, 2008

Three University of Central Florida scientists have set out on an ambitious project — help determine how best to preserve the state’s wetlands and the cattle that thrive there.

UCF professors John Fauth, David Jenkins and Pedro Quintana-Ascencio have spent the past two years working with the MacArthur Agro-Ecology Research Center in Lake Placid. They’ve delved into one of the largest studies ever done on wetlands, a project likely to take several more years to complete.

Jenkins said the study is valuable to Florida because it looks into two important aspects: cattle ranching and wetlands.

“Before I came to UCF in 2003, I had no idea that Florida was so important to the cattle industry nationwide. It is, and I think that fact is probably not common knowledge among Florida’s citizenry,” he said.

“I think Florida’s cattle ranches are undervalued for their place in the history, economy and culture of Florida, and that Florida needs to consider them as more than acreage that can be turned into subdivisions,” he said.

Wetlands are vital to the state’s cattle ranches, the scientists said. They are excited about the effect of this project because it could help ranchers get more from their land.

The study is taking place at the research center — a 10,500-acre working cattle ranch in Highlands County that is also home to many species, including wood storks, bald eagles and black bears. The U.S. Department of Agriculture’s Managed Ecosystems Program is paying for the study.

The UCF professors teach a variety of topics, including biology and ecology. They travel to the research center several times a year to study the land.

“We work very hard and long hours when we’re there, but it’s very peaceful — beautiful skies and nice and cool at night,” Fauth said.

Jenkins said they are testing how prescribed burns, fertilizers and cattle grazing affect the wetlands.

“Most wetland scientists can guess well what should happen with any one of those, but the simultaneous and interactive effects are not clear,” he said. “We’re studying 40 wetlands, akin to an experiment in a lab with 40 test tubes or a greenhouse using 40 pots.”

“That’s no big deal in a test-tube rack or a greenhouse. But it is another scale altogether to pull this off in 40 different ecosystems.”

Jenkins said, in the end, the study could help the public — including ranchers — understand and value the wetlands.

“Florida has already lost more wetland acreage than any other state, and we stand to lose more as we change land use,” he said.

“I think this study is important to Florida’s wetlands because we will help figure out what makes them tick and thus how to better manage the wetlands we can keep.”

UCF’s Graduate Programs Rank Among the Best 100 in the Nation

Dtae: Monday Apr. 07th, 2008

Several of the University of Central Floridas programs were ranked among the best in the nation in the 2009 U.S. News and World Report Best Graduate School guide.

The universitys electrical engineering graduate program was among the highest ranked of UCF programs coming in at 65. Education, physics, public affairs and speech-language pathology programs were also ranked in the top 100.

U.S. News and World Report collected data from more than 12,000 graduate programs for this years guide. It contains rankings of more than 1,500 graduate school programs in categories such as business, education, engineering, law and medicine.

The fact that US News and World Report is recognizing the improving quality of our graduate programs is indicative of the growth and maturity of UCF, said Patricia Bishop, Vice Provost and Dean of Graduate Studies.

The university has been steadily building its graduate programs and research, hiring outstanding faculty, admitting excellent students, and providing a quality learning environment, and we are appreciative of the recognition that we are now receiving, she said. “This national recognition makes it even easier for us to recruit students and faculty so that we can further improve our programs.”

Educations graduate program ranked 75. Physics was 86. Speech-language pathology was 87, and public affairs came in at 90.

For UCFs College of Electrical Engineering and Computer Science, this was the fourth year the program was ranked. It improved its standing from 69 to 65.

We are tremendously encouraged by the growing public awareness of our EECS graduate programs, said professor Issa Batarseh, who is also the director of the school.

He noted that the schools students have earned several national recognitions during the past year. Faculty is earning record-setting research funding and several professors have earned prestigious honors.

With these achievements, I expect to see the schools ranking to continue to increase, Batarseh said.

Future ‘Quantum Computers’ Will Offer Increased Efficiency and Risks

Date: Friday Mar. 07th, 2008

An unusual observation in a University of Central Florida physics lab may lead to a new generation of “Quantum Computers” that will render today’s computer and credit card encryption technology obsolete.

The observations are documented this week in the online version of Nature Physics under Advance Online Publication (http://www.nature.com/nphys/index.html ). The title of UCF Professor Enrique del Barco’s paper is “Quantum Interference of Tunnel Trajectories between States of Different Spin Length in a Dimeric Molecular Nanogmagnet.”

Consumers, credit card companies and high-tech firms rely on cryptography to protect the transmission of sensitive information. The basis for current encryption systems is that computers would need thousands of years to factor a large number, making it very difficult to do.

However, if del Barco’s observation can be fully understood and applied, scientists may have the basis to create quantum computers — which could easily break the most complicated encryption in a matter of hours.

Del Barco said the observation may foster the understanding of quantum tunneling of nanoscale magnetic systems, which could revolutionize the way we understand computation.

“This is very exciting,” del Barco said. “When we first observed it, we looked at each other and said, ?That can’t be right.’ We did it again and again and we achieved the same result every time.”

According to quantum mechanics, small magnetic objects called nanomagnets can exist in two distinct states (i.e. north pole up and north pole down). They can switch their state through a phenomenon called quantum tunneling.

When the nanomagnet switches its poles, the abrupt change in its magnetization can be observed with low-temperature magnetometry techniques used in del Barco’s lab. The switch is called quantum tunneling because it looks like a funnel cloud tunneling from one pole to another.

Del Barco published paper shows that two almost independent halves of a new magnetic molecule can tunnel, or switch poles, at once under certain conditions. In the process, they appear to cancel out quantum tunneling.

“It’s similar to what can be observed when two rays of light run into interference,” del Barco said. “Once they run into the interference you can expect darkness.”

Controlling quantum tunneling shifts could help create the quantum logic gates necessary to create quantum computers. It is believed that among the different existing proposals to obtain a practical quantum computer, the spin (magnetic moment) of solid-state devices is the most promising one.

“And this is the case of our molecular magnets,” del Barco said. “Of course, this is far from real life yet, but is an important step in the way. We still must do more research and a lot of people are already trying to figure this out, including us. It’s absolutely invigorating.”

Co-authors of the paper are Christopher Ramsey from UCF, Stephen Hill from the University of Florida and Sonali J. Shah, Christopher C. Beedle and David N. Hendrickson from the University of California at La Jolla.

Del Barco, who is a native of Spain, began teaching at UCF in 2005. He got a Ph.D degree from the University of Barcelona before moving onto New York University where he worked with Andrew Kent, a well-known quantum physicist.

It was the warm weather and the dynamic of UCF that drew him and his family to UCF. Aside from teaching physics and working on research, Del Barco is a published writer. He penned a science fiction novel that has been published in Spain by Editorial Equipo?Sirius. He collaborates with scientists from around the world including researchers in Spain, Hong Kong and across the United States.