About one mile from the Gant plaza, Goodwin Elementary School teaches some really bright kids. On January 15, 2019, science teacher Nancy Titchen and Goodwin teachers brought the entire 3rd grade class on a field trip to the Physics Learning Labs mock-up studio for some science fun. Students enjoyed a liquid nitrogen show, witnessed quantum effects in superconducting magnetic levitation, experienced mechanics concepts such as angular momentum, and learned about vibrations and the phenomenon mechanical of resonance. The expert hands of a star team of PhD students (Erin Curry and Donal Sheets) and new laboratory technicians (James Jaconetta and Zac Transport) ensured students had a great time and learned some interesting science. Big thanks to the staff and the Goodwin School!
UConn astrophysicist, Cara Battersby. (Carson Stifel/UConn Photo)
A young Cara Battersby once scrawled out the phrase “Science is curious” in a school project about what she wanted to do when she grew up.
This simple phrase still captures Battersby’s outlook on her research about our universe.
Recently shortlisted for the 2018 Nature Research Inspiring Science Award, Battersby has been working on several projects aimed at unfolding some of the most compelling mysteries of galaxies near and far.
“I’m really interested in how stars are born,” Battersby says. “They’re the source of all life on Earth.”
Many of the “laws” we know about how stars are formed are based exclusively on observations of our own galaxy. Because we don’t have as much information about how stars form in other galaxies with different conditions, these laws likely don’t apply as well as we think they should.
Battersby is leading an international team of over 20 scientists to map the center of the Milky Way Galaxy using the Submillimeter Array in Hawaii, in a large survey called CMZoom. She was recently awarded a National Science Foundation grant to follow-up on this survey and create a 3D computer modeled map of the center of the Milky Way Galaxy.
The center of our galaxy has extreme conditions similar to those in other far-off galaxies that are less easily studied, so the Milky Way is an important laboratory for understanding the physics of star formation in extreme conditions.
By mapping out this region in our own galactic backyard, Battersby will be able to form a better idea of how stars form in more remote areas of the universe.
“I love that astrophysics is one of the fields where I can get my hands into everything,” Battersby says. “Stars are something real that you can actually see and study the physics of.”
Battersby is also investigating the “bones” of the Milky Way. Working with researchers from Harvard University, she is looking at how some unusually long clouds could be clues to constructing a more accurate picture of our galaxy.
“Because of the size of our galaxy, it’s infeasible to send a satellite up there to take a picture,” she says.
Since we are living within the Milky Way it is much harder for us to get a clear idea of what it looks like. We know that the Milky Way is a spiral galaxy, but we don’t yet know how many “arms” the spiral has and if it’s even a well-defined spiral.
These kinds of celestial mysteries have long fascinated Battersby.
Battersby says she would “devour” astronomy books and magazines her parents gave her, but it wasn’t until college that her passion truly developed.
She did her Ph.D. thesis at the University of Colorado on high-mass stars being formed on the disk of our galaxy. During this research she made an astounding discovery that every high-density cloud in space is already in some phase of forming a star, a process that takes millions of years.
This led her to conclude that star formation starts as the cloud is collapsing bit by bit, modifying previous ideas of the timeline of this process.
“If you look at something new in a way no one’s looked at it before, the universe has a great way of surprising us,” Battersby says.
In August 2018, Professor Barrett Wells entered as the new head of the Physics department, following Professor Nora Berrah. Barrett is an experimental condensed matter physicists with a robust research program involved in both synthesis and advanced experimentation around novel phases of quantum materials. Barrett brings to the department strong administrative talent, having served a long term as the associate department head for undergraduate affairs as well as chairing many important committees since his arrival at UConn.
Learn more about Professor Wells and the physics department from a recent interview produced by the College of Liberal Arts and Sciences.
Connor Occhialini – Finalist 2018 LeRoy Apker Undergraduate Achievements Award
by Jason Hancock
One of our star undergraduates, Connor Occhialini, has won national recognition as a finalist in the 2018 LeRoy Apker Undergraduate Achievements Award competition for his research in the UConn Physics department. The honor and distinction is awarded not only for the excellent research achievements of the student, but also for the department that provides the supportive environment and opportunities for students to excel in research. Connor is in fact the second Apker finalist in three years’ time (Michael Cantara was a 2016 Apker finalist). Connor graduated with a BS in Physics from UConn in May 2018 and stayed on as a researcher during summer 2018. During his time here, he developed theoretical models, helped build a pump-probe laser system, and carried out advanced analysis of X-ray scattering data which revealed a new context for an unusual phenomenon – negative thermal expansion. With these outstanding achievements, the department presented Connor’s nomination to the 2018 LeRoy Apker award committee of the American Physical Society. Connor was selected to be one of only four Apker finalists from all PhD-granting institutions in the US. With this prestigious honor, the department receives a plaque and a $1000 award to support undergraduate research. Connor is now a PhD student in the Physics Department at MIT.
The Department of Physics seeks 2 dynamic and energetic applicants to join its teaching laboratory team. The Department is undergoing a deep renovation of teaching pedagogy in large-scale learning labs with full support of the University. The successful applicant will fill the Laboratory Technician 2, UCP 4 designation and assume responsibility for maintaining, troubleshooting, and organizing equipment related to learning activities in the large-scale introductory courses. In addition, the technician will be expected to provide support and training to graduate and undergraduate teaching assistants and interact professionally with the teaching staff team, students, and faculty to ensure the safe and secure operation of our teaching labs. Additional duties will include maintaining and upgrading equipment, developing new educational tools under supervision, evaluating and designing laboratory procedures, providing administrative support related to the teaching labs, and assisting in the training, support, and evaluation of teaching assistants. For information about the Physics Department, please visit: http://www.physics.uconn.edu/.
Bachelor’s degree in physics or a related field and 1-3 years experience in teaching laboratory operations, or equivalent education and experience; sound knowledge of principles of and experience in experimental physics; ability to perform and explain lab procedures and edit manuals; working knowledge of standard MS Office software; ability to operate and maintain computer-based laboratory equipment; knowledge of laboratory safety procedures; ability to troubleshoot equipment similar in type and complexity to existing lab equipment; ability to perform tasks requiring manual dexterity and lift 40 lbs; ability to support evening labs as needed.
Strong written and verbal communication skills; familiarity with PASCO proprietary hardware and software; demonstrated ability to work well with students, faculty and staff in a diverse environment; familiarity with the LaTeX typesetting system; ability to create schematic drawings of experimental equipment; ability to revise current experiments and design new experiments; ability to design and perform basic repairs to electric circuits and electronic equipment; familiarity with basic experimental data analysis techniques and software tools; basic proficiency writing code in Python (or equivalent); familiarity with science education research; familiarity with studio-based instructional models;
This is a full time, 12-month permanent position with excellent benefits.
For full consideration, interested applicants should submit letter of application, resume, names and contact information for three professional references to UConn Careers. Employment of the successful candidate is contingent upon the successful completion of a pre-employment criminal background check. (Search #2019124).
All employees are subject to adherence to the State Code of Ethics which may be found at http://www.ct.gov/ethics/site/default.asp.
[The] James Webb [Space Telescope] will begin teaching us entirely new things … things we don’t even know about. — Jonathan Trump
Just like the highly anticipated release of a new phone, game, or gadget, astrophysicists worldwide are eager to start using the new telescope, the latest technology for viewing distant elements of our universe, which is currently set to launch in 2019. But rather than stand in line for hours outside a store, researchers had to submit compelling proposals to secure their spot in line and an opportunity to use the new technology.
The highly competitive, peer-reviewed James Webb Space Telescope Early Release Scienceprogram was created to test the capabilities of the new observatory and to showcase the tools the telescope is equipped with. Of more than 100 proposals submitted, only 13 were chosen to participate in the early release phase, including two separate proposals involving UConn researchers Kate Whitaker and Jonathan Trump, both assistant professors of physics.
Passing the Telescope Torch
The James Webb Space Telescope, designed to be a large space-based observatory optimized for infrared wavelengths, will be the successor to the Hubble Space Telescope. The Hubble telescope has been a versatile workhorse and vital tool since its launch in 1990, allowing researchers to peer deep into space and get crisp glimpses of distant galaxies.
But it has technological limitations, and is not currently scheduled for any upgrades or servicing. Since its last service in 2009, Whitaker says, many researchers have been keeping their fingers crossed that it would continue functioning. Hubble is currently the only way to make observations that are required for the type of research she and many others conduct.
“A lot of my research right now is pushing Hubble to its limits,” she notes. “It’s an exciting time, because with the capabilities of the James Webb Space Telescope, we will really push into the frontiers of research.”
The James Webb Space telescope is equipped with tools that will surpass Hubble’s capabilities. Webb will be launched further into space and will be capable of powerful imaging that will produce sharper images and be able to capture images into the infrared range.
Peering into the infrared range allows researchers to observe signatures, in the form of light, from events that happened long ago. The universe is constantly expanding and as light travels, it gets stretched over time, Whitaker explains. The further back you go, say a few billion years or so, the light is stretched so much that it will shift from the visible region of the spectrum into the infra-red.
“Since we cannot travel to these distant galaxies, all we can do is sit here and wait for their light to reach our telescopes,” says Whitaker.
Trump is a co-investigator on the proposal called “CEERS: The Cosmic Evolution Early Release Science Survey,” a plan to conduct an extragalactic survey in hopes of gaining insights into the formation of the first galaxies following the big bang. They plan to look at aspects of the assembly of galaxies, including their number density, chemical abundance, star formation, and the growth of supermassive black holes.
“Hubble has totally transformed our view of the universe and James Webb will begin teaching us entirely new things,” Trump says. “I’m incredibly excited to think about all of the things we don’t even know about, that James Webb will begin to tell us.”
The Early Release Program is aimed not only to showcase the capabilities of the James Webb Space Telescope right away, but to make the data publicly available as soon as possible. It is anticipated that the data will facilitate huge breakthroughs in research.
Stay tuned: 2019 promises to be an exciting year in astrophysics.
On Monday, August 21, 2017, the moon eclipsed the sun across the US. What began as a small organic outreach activity blossomed into an epic community event. With help from UConn communications, the UConn Physics club, and staff in the physics department, astronomers Jonathan Trump, Cara Battersby, and Kate Whitaker hosted an eclipse viewing event open to the public. Solar projectors, solar glasses, and solar telescope drew and estimated 2,000 visitors, including many children and families to share in the majesty of the heavens. To read more about the great American eclipse, read the recent UConn Today article by Elaina Hancock, featuring commentary by astronomers Trump and Cynthia Peterson.
For more about the event and others around the state, see this article in the Hartford Courant
Whoever said rules were made to be broken wasn’t a physicist. When something doesn’t act the way you think it should, either the rules are wrong, or there’s new physics to be discovered. Which is exactly what UConn’s Connor Occhialini ’18 (CLAS), an honors student majoring in physics and math, found when he began researching scandium fluoride.
Scandium fluoride is a transparent crystal with a cubic shape, a byproduct of mining. It’s not used commercially and it wouldn’t be particularly interesting to anyone except for one odd thing: it shrinks as it warms.
Most materials swell as they heat up. Really simple materials like hydrogen gas swell because the heat makes their atoms zoom around faster, bumping into each other more, so the same number of hydrogen atoms need more space. More complicated materials also swell, which is why your wooden front door tends to stick in the summertime. But solids like wood can’t swell as much as a gas because their atoms are tightly linked together into long, interlocked molecules, so they just jiggle around, swelling the door a little bit.
Scandium fluoride must be doing something else, reasoned Occhialini. His advisor for his honors physics project, Jason Hancock, had been working with scandium fluoride, and asked Occhialini to study a model of the crystal’s dynamics. Scandium fluoride has a pretty simple structure: it’s a solid crystal, with each scandium atom surrounded by six fluorines to make stacks of octahedra (eight-sided diamonds). The researchers hoped the simple structure might be easy to understand. Understanding scandium fluoride’s strange ‘negative thermal expansion’, as physicists call the heat-related shrinkage, might yield more general insight into other, more complex materials that do the same thing.
Occhialini’s first step was to simplify the problem. So instead of a three-dimensional crystal, he decided to think about it as a two-dimensional sheet that looks like this:
Each black diamond represents a molecule of scandium fluoride. The scandium atoms (blue dots) are at the center of each diamond, and a fluorine atom is at each corner.
Most of the time, bonds between atoms are flexible. So in a normal crystalline solid – calcium fluoride, for example – the fluorines and calcium atoms would all be able to wiggle around independently when the material warmed up. As they wiggled, they’d take up a little more space, and the solid would swell. Normal solid behavior.
But Occhialini wondered if maybe that wasn’t what was happening in scandium fluoride. Maybe in this model, he should assume the bonds connecting each fluorine to its scandium were stiff? So stiff the fluorine-scandium bonds don’t move at all, so the diamonds are like solid blocks. The only places the structure would be able to flex when it warmed up would be at the fluorine atoms, which would act like tiny little joints. As the crystal heated up, the little scandium fluoride blocks would tilt around the fluorines at the corners. That’s what you see happening in the picture. You’ll notice that when the diamonds tilt, the whole structure gets smaller. It actually tightens up. The blue outline shows the structure at its coldest, perfectly ordered state, with no molecular motion. When the diamonds tilt, they take up a smaller total volume than the blue outline delineates. This is negative thermal expansion.
Occhialini figured out that you can describe this shrinkage mathematically, using just the angle of the molecules’ tilt. He called the angle Θ (theta). When the scandium fluoride blocks tilt by an angle Θ, the distance between the center of each block shortens by a factor of cosine Θ, and the crystal’s total volume shrinks.
To calculate that shrinkage (or, in a normal material, expansion) in detail, Occhialini added a third term to the classic equation that describes the energy of a vibrating crystal. The first two terms in the standard equation describe the potential energy a crystal has from the bending at each molecular junction, plus the kinetic energy of rotation of each molecule. Occhialini’s equation also describes the translational kinetic energy of the molecules–not just from rotating around, but also moving toward and away from their original positions as they rotate. The further they are from the center of mass of the crystal, the more they move. Look back at Figure 1 and notice the dot in the middle; that’s the center of mass. The diamonds in the middle barely move in relation to it, while the diamonds at the edges move a lot. Now imagine how much of a difference there would be if the crystal had millions of molecules instead of just 25. And now you understand how important that third term could be to the energy of the crystal.
Now, molecules being molecules, they don’t just shrink and stay there. They’re moving constantly, and the warmer they get, the more they move. Part of Occhialini’s insight is that, on average, the molecular structure gets bendier the warmer it gets. So the molecules tilt more and spend more time at bigger values of Θ, closer to 45 degrees. After Occhialini thought it over for a while together with Hancock and physics Ph.D. students Sahan Handunkanda and Erin Curry, they realized there was a geometric shape that had the same mathematical description. It’s Archimedes’ spiral pendulum, and it looks like this:
Each turning of the spiral is exactly the same distance from the last. That spacing – the distance between turns – is controlled by Θ. Imagine a line that stretches from the center of the sphere to a point on the spiral. The angle between that line and the pole of the sphere is Θ. You see the little ball traveling along the spiral? That’s the end of the imaginary line. As Θ gets bigger, the ball moves towards the equator.Imagine that the ball represents the instantaneous state of the scandium fluoride crystal – the physicists calculated the statistical average of what every molecule in the crystal is doing. You’ll notice the ball spends more time near the equator of the spiral sphere, that is, it tends to hang out where Θ is large. If the temperature of the crystal drops and the molecules wiggle less, Θ gets smaller, the more time the ball spends near the pole of the sphere and the less the crystal shrinks.
So not only can a really weird phenomenon of a crystal that shrinks as it warms be explained by just assuming the molecules are rigid, but it can be illustrated with a classical geometric shape!
Occhialini was just a freshman when Hancock introduced him to the scandium fluoride puzzle. He had to learn the math as he went, but after about two semesters of working on it he’d figured out the equation that described what was going on. Now in his senior year, he says his research experiences in Hancock’s lab have been integral to his experience as an undergraduate.
The equation works beautifully and explains certain aspects of Hancock’s experimental x-ray measurements as well.
“I learned a lot more doing research than any course could have given me,” Occhialini says.
And now you, dear reader, have learned a little bit, too.
Please join the Department of Physics at UConn for a Solar Eclipse Viewing Party!
Hosted by Prof. Cara Battersby, Prof. Jonathan Trump, and Prof. Kate Whitaker
August 21 2017, Horsebarn Hill 1:00 – 4:00 PM (next to Dairy Bar) weather permitting
From our location, the solar eclipse begins at 1:25pm and ends at 4:00pm. Maximum (partial) occultation occurs at 2:45pm.
The organizers have 150 solar eclipse glasses available on a first-come, first-serve basis (encouraging folks to recycle them when they are
done). No reservations are necessary. Here is the schedule of the events:
2:00pm Short Tutorial on Eclipses
2:45pm Maximum (partial) occultation
3:15pm Ask an Astrophysicist
There will be also an ongoing activity from 1-4pm making pin-hole cameras (great for kids!), while supplies last. Finally, there will be 4 solar
telescopes set up for the entire event.
All ages are welcome!
Join our mailing list for updates: http://tinyurl.com/uconn-astro-mailing-list
A spectacular and likely unforgettable show will take place in the sky Aug. 21.
“Have you ever seen a total solar eclipse?” asks Cynthia Peterson, professor emerita of physics. “It’s a really, really exciting event!”
The reason she and so many others are excited for this event has a lot to do with its rarity. The last time a total solar eclipse was visible from the mainland United States was 38 years ago, in February 1979.
Very specific conditions have to be met to create an eclipse that can be viewed from Earth. The Earth and the moon must align perfectly with the sun as they speed through space, an amazing coincidence. To fully understand how this happens, Peterson says, it’s helpful to know some basic astronomy.
Conditions for a Total Solar Eclipse
The Earth moves in space around the sun, completing a full orbit once every 365.25 days, she explains. As the Earth and other members of our solar system travel around the sun, they continue in essentially the same plane, on a path called the ecliptic. Some celestial bodies, such as our moon, deviate from the ecliptic slightly.
The orbit of the moon is inclined on the ecliptic plane at an inclination of 5 degrees. As the moon deviates 5 degrees above or below the ecliptic plane, it will cross the plane at points called nodes.
“That is the first essential piece of the eclipse puzzle,” says Peterson. “The moon must be at a node for an eclipse to occur. Otherwise, the moon will not align and no eclipse will be seen from Earth.”
The moon’s position in the lunar cycle is another vital eclipse component. As the Earth travels in its orbit, the moon tags along, keeping its gaze locked on Earth, always facing from the same side as it completes its own orbit around Earth once every 29.5 days. Over the course of a month, the moon’s appearance changes, from crescent to full to crescent again and finally to what appears to be its absence, when it’s called a new moon. A new moon is the other requirement for a solar eclipse.
“The basic rule for a solar eclipse is to have a new moon at a node,” Peterson points out.
But during an eclipse, how can our moon, which is relatively small, appear almost as big as the sun, which is pretty gigantic?
Peterson explains, “The sun is 400 times bigger than the moon and the sun is also 400 times farther away from the moon, so the moon appears to fit exactly during an eclipse, when they are both the same angular size.”
Holding up her fist, she demonstrates: “Find a large object ahead of you and pretend it is the sun and your fist is the moon. If you hold up your fist and look with one eye, you can’t see the object/sun.”
These are the conditions for a total solar eclipse like the one coming up. “Solar eclipses happen when the new moon obstructs the sun and the moon’s shadow falls on the earth, creating a total solar eclipse.” Peterson moves her fist slightly away from herself until the edges of the object can be seen around it. “Or, when the moon covers the Sun’s center and creates a ‘ring of fire’ around the moon, it’s what’s called an annular eclipse.”
It’s those bits of the sun peeking out from behind the moon – in both partial and total eclipses – that everyone needs to be careful of. It’s extremely important to view the eclipse safely, Peterson stresses. “The problem with the eclipse is that every time it happens, some people are blinded [from looking at it unprotected]. The shadow goes whipping by at 1,000 miles per hour, and you never want to stare at the sun, even a sliver of it.”
So be prepared, and ensure you wear proper solar eclipse eye protection. Regular sunglasses will not help. Solar eclipse glasses can be used, welder’s goggles, or telescopes with proper lenses. Be sure the eye protection you choose is certified by the International Organization for Standardization (ISO). Other popular viewing methods are DIY viewing boxes like these.
Peterson, like many others who wish to get the full eclipse experience, will be traveling to an area directly in the path of the eclipse’s shadow. These areas are called totality. The Aug. 21 eclipse will cover an expansive area of totality that will include 14 states and 14 major U.S. cities, stretching from Lincoln Beach, Oregon to Charleston, South Carolina. For a map of the path of totality, go to the NASA website. Connecticut is unfortunately hours of travel from the nearest totality. Peterson will go as far as Nebraska for the experience.
“You’ll only see a partial eclipse here in Connecticut,” she says. “It will get a little darker, like a cloud covering part of the sun, and then brighten up again.”
She encourages those who can to try to travel to a viewing point for the total eclipse, where they may see “amazing phenomena” like the diamond ring, shadowbands, crescent-shaped solar images under trees (instead of the usual ‘coins’ which are pinhole images of the sun), and extremely sharp shadows in the final minute before totality, due to the very narrow sun at that time. “These phenomena can only be seen in totality,” she says.
The next chance to see a total solar eclipse will be in 2024, when its shadow will be cast closer to Connecticut. It will start in the U.S. in Texas, then make its way north, through northern Vermont and New Hampshire.
“That’s less than seven years from now,” Peterson points out, “but that’s the end of eclipses crossing the U.S. until the 2050s.”
For those on campus next week, you aren’t out of luck. For this eclipse there will be a viewing party on Horsebarn Hill behind the Dairy Bar, from 1 to 4 p.m., hosted by the Department of Physics. “We’ll have solar telescopes, a pinhole camera activity, and will do some short mini-lectures on astronomy at UConn and about how eclipses work,” says Assistant Professor of Physics Jonathan Trump, one of the faculty members who will lead the viewing party.
Peterson, longtime astronomer and scientist, says witnessing an eclipse – especially a total eclipse – can be extremely emotional. She suggests reading Annie Dillard’s essay about solar eclipses, where the author compares the contrast between viewing a partial eclipse and viewing a total eclipse to the difference between flying in an airplane versus falling out of the airplane. “Those are very different experiences.”
But wherever you are on the afternoon of Aug. 21, Peterson says, stop and enjoy the show: “Good luck and clear skies!”
The eclipse will be live-streamed by NASA, and can also be viewed on PBS’ NOVA at 9 p.m. on Aug. 21.