UM Establishes Center for Researching Multi-messenger Astrophysics

Emergent scientific field arose from discovery of gravitational waves

Neutron stars – pictured in this artist’s illustration of two merging neutron stars – are among the phenomena to be studied at the new UM Center for Multi-messenger Astrophysics. The narrow beam represents the gamma-ray burst, and the rippling spacetime grid indicates the isotropic gravitational waves that characterize the merger. Swirling clouds of materials ejected from the collision are a possible source of the light that was seen at lower energies. Graphic courtesy National Science Foundation/LIGO/Sonoma State University/A. Simonnet

OXFORD, Miss. – Riding a new frontier of scientific discovery into gravitational waves, the University of Mississippi is now home to the Center for Multi-messenger Astrophysics.

The center was launched Nov. 1 after the center’s creation was approved by the Mississippi Institutions of Higher Learning in August. It will allow UM researchers to play a prominent role in the emergent field of multi-messenger astrophysics, which is a new branch of science born in 2015 through the discovery of gravitational waves by the Laser Interferometer Gravitational-wave Observatory, or LIGO.

Multi-messenger astrophysics studies “messengers” – electromagnetic waves, high-energy particles and gravitational waves – to reveal information about the universe.

“That event really opened up a new branch of astronomy and astrophysics,” said Marco Cavaglia, professor of physics and astronomy and the center’s director. “Since the dawn of humanity, most, if not all, of the information we had from the universe was in the form of light, with some exceptions because we also use particle physics.

“Gravitational waves are a completely new way of looking at objects – for example looking at black holes, what happens to the center of stars when they explode and even the beginning of the universe.

“The main goal is to learn more about the universe, how the universe works. This is really frontier science. Science has always been motivated by trying to understand the world and the universe around us.”

Marco Cavaglia, UM professor of physics and astronomy and an active member of the LIGO Scientific Collaboration, is director of the new Center for Multi-messenger Astrophysics. Photo by Robert Jordan/Ole Miss Digital Imaging Services

Cavaglia also is principal investigator of the UM Laser Interferometer Gravitational-Wave Observatory Group, which is an active member of the LIGO Scientific Collaboration.

Last year, the LIGO detectors, along with the Europe-based Virgo detector and some 70 ground- and space-based observatories, directly detected gravitational waves – ripples in space and time – in addition to light from the merging of two neutron stars. It was the first time that a cosmic event has been viewed in both gravitational waves and light.

The center will allow Ole Miss faculty and students to further their research into the field and build upon existing research programs and expertise of faculty within the Department of Physics and Astronomy, where the center will be housed. Plans call for adding two additional full-time faculty members affiliated with the center in fall 2019, with at least one more added by 2021.

The center also will support several post-doctoral research associates and graduate student research assistants.

“The experimental detection of gravitational waves marked a historic event in physics, and UM is so proud to have played a role in that discovery,” said Josh Gladden, UM vice chancellor for research and sponsored programs. “With strengths in high energy physics, observational astronomy and now gravitational waves, UM is well-positioned to establish a Center for Multi-messenger Astrophysics.”

This new branch of physics has exploded, and the time is right to have a center dedicated to multi-messenger astrophysics that will boost the image of the department while conducting groundbreaking research, Cavaglia said.

“I really hope that it will help put Mississippi on the map more when it comes to this kind of research,” he said. “And it will attract and retain new faculty and students. This is an emerging field.

“It will really help recruit bright minds from around the world to come here and do research. That aligns well with the research mission of the university and also its educational component. And it’s cool. It’s cool stuff.”

Students Study Physics During UM Spring Break Visit

Project prepares high school students for AP Physics

Marco Cavaglia, a UM professor of physics and astronomy, spends his spring break educating Mississippi high school students about physics as part of a Global Teaching Project program. Photo by Thomas Graning/Ole Miss Communications

OXFORD, Miss. – It was probably the first time Yung Bleu’s hip-hop had been used to teach physics.

Yet, in Marco Cavaglia’s University of Mississippi classroom during spring break, the artist’s music played, causing the electronic waves of an oscilloscope to bounce and jiggle with the vibrations of the music.

Huddled around the oscilloscope, learning about gravitational waves through the Alabama artist’s work, stood 28 Mississippi high school students from rural school districts, visiting the Ole Miss campus during spring break as part of a Global Teaching Project program.

The program is an initiative to provide potentially high-achieving secondary school students, regardless of their circumstances, access to the quality teaching they need to fulfill their potential, with an initial focus on science, technology, engineering and mathematics courses, said Matt Dolan, founder and CEO of the Global Teaching Project.

For the 2017-18 school year, the project has worked with the Mississippi Public School Consortium for Educational Access to implement a three-year pilot program to teach Advanced Placement Physics 1 in rural, low-income areas with high schools that did not previously offer the course and where shortages of qualified teachers are most acute. The subject was chosen largely based on assessments by Mississippi educators of their most pressing curricular needs.

“Multiple studies show significant benefits from taking AP classes,” Dolan said. “Students who do well on the exams significantly boost their college admission prospects, and possibly save money through expanded college scholarship opportunities and the ability to earn college credit without taking college courses.

“Studies also show that all students, even those with modest test scores, tend to benefit from exposure to advanced material and by developing the study skills to handle rigorous material.”

According to the College Board, the nonprofit that oversees the AP Program, more than 2.6 million U.S. students took an AP exam in 2017, but in Mississippi, only 10,580 students took such an exam. Only 527 Mississippi students took the AP Physics 1 exam in 2017, with only 175 passing.

Students from consortium high schools in Aberdeen and Booneville, and Coahoma (Coahoma Early College High School), Holmes, Pontotoc, Quitman and Scott counties participated in the spring break program.

The AP Physics 1 course is provided at no cost to students, schools or school districts. Funding for the consortium comes entirely from the private sector.

The Jack Kent Cooke Foundation, which is focused on promoting educational opportunities for promising students from underserved areas, provided significant support to the consortium, Dolan said, and the Global Teaching Project has borne much of the costs itself.

Although the AP class features numerous online components, it is not an online course. The lead instructor is Meg Urry, a professor of physics and astronomy at Yale University, who teaches primarily via asynchronous video but also has come to Mississippi to teach students in person.

Students also are instructed through textbooks, online resources, physics majors from Yale and the University of Virginia who tutor through video conferences and virtual whiteboards, and on-site teachers.

The Global Teaching Project plans to add more AP courses and school districts for 2018-19.

The students who visited the Ole Miss campus during spring break came for a number of reasons, Dolan said. There was the objective of providing additional academic support and reviewing the AP Physics 1 material as the May exam date nears. The visit also provided younger, prospective students an understanding of what the course entails, and what students must do to prepare for that level of academic rigor.

And, in some small respect, the three-day visit was designed to give high school students the college experience.

Undergraduate physics major Renee Sullivan-Gonzalez demonstrates the big bang to Mississippi high school students involved with the Global Teaching Project program. Photo by Thomas Graning/Ole Miss Communications

“It was exciting to partner with the Global Teaching Project to improve access to higher education for some of Mississippi’s most underserved high school students,” said Robert Cummings, UM coordinator for the visit and executive director of academic innovation. “While it is painful to think that world-renowned researchers like Dr. Cavaglia are located just a few miles from high school students who might have no high school physics courses, texts or teachers, it is also equally rewarding to see the two come together.

“It is moments like these that remind me that the University of Mississippi is a special place, endowed with a powerful capability to render real change in our world.”

The visit included staying at The Inn at Ole Miss, a tour of campus, information from the Foundations for Academic Success Track and the Grove Scholars Program, a presentation from the Office of Admissions and lots of physics reviewing.

While spring break on the UM campus is typically a quieter time, a pause to recharge, reevaluate and even relax before the sprint to the spring Commencement finish line, students spent part of their visit learning about physics from Cavaglia, a professor of physics and astronomy and principal investigator of the UM Laser Interferometer Gravitational-Wave Observatory Group. The LIGO Group – as it is known – is an active member of the LIGO Scientific Collaboration.

Late last year, the LIGO Group, along with the Europe-based Virgo detector and some 70 ground- and space-based observatoriesdirectly detected gravitational waves – ripples in space and time – in addition to light from the merging of two neutron stars. It was the first time that a cosmic event has been viewed in both gravitational waves and light.

To demonstrate how gravitational waves are detected, Cavaglia asked for some music from the students, and Bleu was cued up. With Bleu’s music playing, rain beat down outside Brevard Hall, reminding everyone that spring break arrives at the tail-end of winter, but the students did not notice – their minds were focused on Cavaglia and the oscilloscope.

“I wanted to convey to them the beauty of astrophysics, but also how the scientific process works and modern science operates,” Cavaglia said. “As an example, LIGO’s discoveries were only possible thanks to the work of over 1,000 people from many countries all working together to achieve this goal for many decades.”

The morning’s lesson did not end with gravitational waves.

Cavaglia, with assistance from physics graduate student Lorena Magana Zertuche and undergraduate physics major Renee Sullivan-Gonzalez, also demonstrated what a black hole is, worked in references to “Star Trek” and “Star Wars” when discussing warping space, and offered students career advice. They even discussed how a physics education could lead to working for Pixar Animation Studios, creator of such films as “Ratatouille,” “Up” and the “Toy Story” franchise.

Sure, Cavaglia could have been busy during spring break furthering his groundbreaking research, but as a scientist, he said it was very important to talk to students and let them know what he does.

“I always felt outreach is an essential part of the education process,” Cavaglia said. “Moreover, explaining current astrophysics research to students may help with recruiting in the sciences.

“Across the U.S., but especially in Mississippi, there is a shortage of scientists and I, as a physicist, should use my resources and time to try to remedy this.”

Whether it was hearing the “chirp” that a gravitational wave creates or answering questions about dark matter and the big bang, Cavaglia kept the students enthralled, including Diem Mi Pham, an 11th-grader at Scott Central High School.

“Oh, it was really interesting,” she said. “I’m very interested in space, and he discussed a lot of things I really care about.”

Scientists Detect Gravitational Waves Produced by Colliding Neutron Stars

Joint LIGO-Virgo discovery marks first cosmic event observed in both gravitational waves and light

An artist’s illustration of two merging neutron stars. The narrow beam represents the gamma-ray burst, and the rippling spacetime grid indicates the isotropic gravitational waves that characterize the merger. Swirling clouds of materials ejected from the collision are a possible source of the light that was seen at lower energies. Graphic courtesy National Science Foundation/LIGO/Sonoma State University/A. Simonnet

OXFORD, Miss. – For the first time, scientists have directly detected gravitational waves – ripples in space and time – in addition to light from the spectacular collision of two neutron stars. This marks the first time that a cosmic event has been viewed in both gravitational waves and light.

The discovery was made using the U.S.-based Laser Interferometer Gravitational-Wave Observatory, known as LIGO, the Europe-based Virgo detector, and some 70 ground- and space-based observatories.

Neutron stars are the smallest, densest stars known to exist and are formed when massive stars explode in supernovas. As these neutron stars spiraled together, they emitted gravitational waves that were detectable for about 100 seconds; when they collided, a flash of light in the form of gamma rays was emitted and seen on Earth about two seconds after the gravitational waves.

In the days and weeks following the smashup, other forms of light, or electromagnetic radiation – including X-ray, ultraviolet, optical, infrared and radio waves – were detected.

“This is really the beginning of multimessenger astronomy,” said Marco Cavaglia, professor of physics and astronomy at the University of Mississippi and principal investigator of the Ole Miss LIGO group. “Since the time humans have first gazed at the sky, people have just relied on light to learn about the universe.

“Today, we proved we can simultaneously observe a cosmic event using two different carriers of information: electromagnetic waves and gravitational waves. This is a revolution in astronomy comparable to Galileo’s first telescopic observations.”

The observations have given astronomers an unprecedented opportunity to probe a collision of two neutron stars. For example, observations made by the U.S. Gemini Observatory, the European Very Large Telescope and NASA’s Hubble Space Telescope reveal signatures of recently synthesized material, including gold and platinum, solving a decades-long mystery of where about half of all elements heavier than iron are produced.

The LIGO-Virgo results are published today in the journal Physical Review Letters; additional papers from the LIGO and Virgo collaborations and the astronomical community have been either submitted or accepted for publication in various journals.

The gravitational signal, named GW170817, was first detected at 7:41 a.m. Aug. 17; the detection was made by the two identical LIGO detectors in Hanford, Washington, and Livingston, Louisiana. The information provided by the third detector, Virgo, situated near Pisa, Italy, enabled an improvement in localizing the cosmic event.

At the time, LIGO was nearing the end of its second observing run since being upgraded in a program called Advanced LIGO, while Virgo had begun its first run after recently completing an upgrade known as Advanced Virgo.

The National Science Foundation-funded LIGO observatories were conceived, constructed, and operated by Caltech and MIT. Virgo is funded by the Istituto Nazionale di Fisica Nucleare in Italy and the Centre National de la Recherche Scientifique in France, and operated by the European Gravitational Observatory. Some 1,500 scientists in the LIGO Scientific Collaboration and the Virgo Collaboration work together to operate the detectors and to process and understand the gravitational-wave data they capture.

Each observatory consists of two long tunnels arranged in an “L” shape, at the joint of which a laser beam is split in two. Light is sent down the length of each tunnel, then reflected back in the direction it came from by a suspended mirror. In the absence of gravitational waves, the laser light in each tunnel should return to the location where the beams were split at precisely the same time. If a gravitational wave passes through the observatory, it will alter each laser beam’s arrival time, creating an almost imperceptible change in the observatory’s output signal.

On Aug. 17, LIGO’s real-time data analysis software caught a strong signal of gravitational waves from space in one of the two LIGO detectors. At nearly the same time, the Gamma-ray Burst Monitor on NASA’s Fermi space telescope had detected a burst of gamma rays.

Rapid gravitational-wave detection by the LIGO-Virgo team, coupled with Fermi’s gamma-ray detection, enabled the launch of follow-up by telescopes around the world.

The LIGO data indicated that two astrophysical objects located at the relatively close distance of about 130 million light-years from Earth had been spiraling in toward each other. It appeared that the objects were not as massive as binary black holes – objects that LIGO and Virgo have previously detected.

Instead, the inspiraling objects were estimated to be in a range from around 1.1 to 1.6 times the mass of the sun, in the mass range of neutron stars. A neutron star is about 12 miles in diameter and is so dense that a teaspoon of neutron star material has a mass of about a billion tons.

“The scientific community has been eagerly awaiting this moment,” says Kate Dooley, UM assistant professor of physics and astronomy and a member of the LIGO team that designed and built the detectors.

“Coalescing neutron stars provide such an exciting laboratory for new physics. We can study how neutrons behave when they’re packed so closely together, and even make an independent measurement of the expansion of the universe. We are tremendously lucky this event was relatively close by and could also be so precisely pinpointed in the sky.”

Theorists have predicted that when neutron stars collide, they should give off gravitational waves and gamma rays, along with powerful jets that emit light across the electromagnetic spectrum. The gamma-ray burst detected by Fermi, and soon thereafter confirmed by the European Space Agency’s gamma-ray observatory INTEGRAL, is what’s called a short gamma-ray burst.

The new observations confirm that at least some short gamma-ray bursts are generated by the merging of neutron stars – something that was only theorized before.

“This result is a great example of the effectiveness of teamwork, of the importance of coordinating and of the value of scientific collaboration,” said Federico Ferrini, director of the European Gravitational Observatory. “We are delighted to have played our relevant part in this extraordinary scientific challenge: Without Virgo, it would have been very difficult to locate the source of the gravitational waves.

Each electromagnetic observatory will be releasing its own detailed observations of the astrophysical event. In the meantime, a general picture is emerging among all observatories involved that further confirms that the initial gravitational-wave signal indeed came from a pair of inspiraling neutron stars.

Approximately 130 million years ago, the two neutron stars were in their final moments of orbiting each other, separated only by about 200 miles and gathering speed while closing the distance between them. As the stars spiraled faster and closer together, they stretched and distorted the surrounding space-time, giving off energy in the form of gravitational waves before smashing into each other.

At the moment of collision, the bulk of the two neutron stars merged into one ultra-dense object, emitting a “fireball” of gamma rays. The initial gamma-ray measurements, combined with the gravitational-wave detection, also provide confirmation for Einstein’s general theory of relativity, which predicts that gravitational waves should travel at the speed of light.

Swope and Magellan telescope optical and near-infrared images of the first optical counterpart to a gravitational wave source, SSS17a, in its galaxy, NGC 4993. The left image is from Aug. 17, 11 hours after the LIGO/Virgo detection of the gravitational wave source, and contains the first optical photons of a gravitational wave source. The right image is from four days later. SSS17a, which is the aftermath of a neutron star merger, is marked with a red arrow. On the first night, SSS17a was relatively bright and blue. In only a few days, it faded significantly and its color became much redder. These observations show that heavy elements like gold and platinum were created in the merger. Photos courtesy 1M2H/UC Santa Cruz and Carnegie Observatories/Ryan Foley

Theorists have predicted that what follows the initial fireball is a “kilonova,” a phenomenon by which the material that is left over from the neutron star collision, which glows with light, is blown out of the immediate region and far out into space. The new light-based observations show that heavy elements, such as lead and gold, are created in these collisions and subsequently distributed throughout the universe.

In the weeks and months ahead, telescopes around the world will continue to observe the afterglow of the neutron star merger and gather further evidence about various stages of the merger, its interaction with its surroundings and the processes that produce the heaviest elements in the universe.

“Gravitational wave astronomy continues to provide exciting new ways to observe our universe,” said Josh Gladden, UM interim vice chancellor for research and sponsored programs. “A particularly exciting aspect of this discovery is that this event could be observed by both traditional electromagnetic (light) astronomy as well as by gravitational waves, which allows for direct comparisons.

“We are proud that our gravity group at Ole Miss continues to provide important contributions to the LIGO effort.”

LIGO is funded by the NSF, and operated by Caltech and MIT, which conceived of LIGO and led the Initial and Advanced LIGO projects. Financial support for the Advanced LIGO project was led by the NSF with Germany (Max Planck Society), the U.K. (Science and Technology Facilities Council) and Australia (Australian Research Council) making significant commitments and contributions to the project.

More than 1,200 scientists and some 100 institutions from around the world participate in the effort through the LIGO Scientific Collaboration, which includes the GEO Collaboration and the Australian collaboration OzGrav. Additional partners are listed at

The Virgo collaboration consists of more than 280 physicists and engineers belonging to 20 different European research groups: six from Centre National de la Recherche Scientifique in France; eight from the Istituto Nazionale di Fisica Nucleare in Italy; two in the Netherlands with Nikhef; the MTA Wigner RCP in Hungary; the POLGRAW group in Poland; Spain with the University of Valencia; and the European Gravitational Observatory, the laboratory hosting the Virgo detector near Pisa in Italy, funded by CNRS, INFN, and Nikhef.

UM communications specialist Edwin Smith contributed to this report.

UM Physicists Celebrate Nobel Prize-Winning Discovery

Historic gravitational wave observation made in 2015 recognized as breakthrough in modern physics

UM physics professor Marco Cavaglia, right, shares a T-shirt with Kip Thorne, one of three recipients of the 2017 Nobel Prize in physics. Submitted photo.

OXFORD, Miss. – Physics researchers at the University of Mississippi are elated over news that colleagues involved in the groundbreaking discovery of gravitational waves in 2015 were awarded the prestigious Nobel Prize in physics Tuesday (Oct. 3).

Rainer Weiss, a professor at the Massachusetts Institute of Technology, and Kip Thorne and Barry Barish, both of the California Institute of Technology, were awarded the prestigious honor for the discovery of ripples in space-time known as gravitational waves, which were predicted by Albert Einstein a century ago but had never been directly seen.

In announcing the award, the Royal Swedish Academy called it “a discovery that shook the world.”

“Kip and Rai are two of the most clever and kind people I ever had the honor of working with,” said Marco Cavaglia, UM professor of physics and astronomy and head of the Ole Miss Laser Interferometer Gravitational-wave Observatory team. “Kip and Rai are always easy to talk with, and humble although they are among the best scientific minds of our time.

“They both remain very active, especially Rai, who, at 85, is still one of the driving forces behind LIGO.”

Cavaglia met Weiss and Thorne more than a decade ago and credits the former for his LIGO connection.

“Over 10 years ago, I was invited to LSU to give a colloquium at the physics department by Jorge Pullin, a professor at LSU working on quantum gravity,” he said. “At that time, I was working on quantum gravity, particle colliders and cosmic rays.

“Gaby Gonzalez, LSU professor and later spokesperson of the LIGO Scientific Collaboration, arranged for me a guided visit to the LIGO Observatory in Livingston, Louisiana, on my way back to Oxford.”

Much to Cavaglia’s surprise, it was Weiss who gave him the tour.

“He spent several hours with me, showing the detector and the lab to me,” Cavaglia recalled. “I was so amazed with the LIGO project and researchers that I started planning to join the LIGO Scientific Collaboration and work on gravitational wave astrophysics. I’ve been working within the LSC ever since then.”

Other UM officials shared their reflections about the prize recipients.

“Rai wrote the first detailed document for the design of the LIGO interferometers in 1983,” said Katherine Dooley, UM assistant professor of physics and astronomy. “We call it the ‘Bluebook’ because of how accurately he predicted all of the noise sources for the detector.

“Rai, himself, is also remarkable for his energy and ability to continue playing an integral role in the detector commissioning to this date.”

Dooley worked at the LIGO Livingston site for four years, installing hardware and commissioning the full interferometer. Weiss was a regular, long-term visitor.

“He always had his pet projects, from tirelessly tracking down leaks in the vacuum system – the largest-volume vacuum system in the world and the most valuable part of the entire detector – to tackling head-on the ‘mystery noise’ that most impeded our progress in commissioning,” she said. “He suspected Barkhausen noise – magnetic domain-flipping – was a culprit and set up experiments to measure it.”

Weiss also played a special role in Dooley’s path to earning her doctorate, she said

“He was the first person to sit me down and make me write an outline for my thesis,” Dooley said. “Rai was always an advocate for us students, and we appreciated that greatly. He wouldn’t hesitate to step in to protect our interests.”

Josh Gladden, UM interim vice chancellor of research and sponsored programs, congratulated the LIGO team on their honor.

“As a physicist, the most exciting moment in my professional career was being on hand in Livingston, Louisiana, for the announcement of the first detection of gravitational waves,” Gladden said. “We are so proud of the contribution that our physics colleagues have made to the LIGO effort and that the Nobel committee has honored this discovery with the highest prize in physics.

“As subsequent discoveries have shown, gravitational waves are going to be an entirely new tool for humans to observe our universe.”

Weiss, in a live phone call with the Nobel Committee minutes after the announcement, said, “I view this more as a thing that recognizes the work of about 1,000 people,” referring to the LIGO Scientific Collaboration.

“We are so pleased that our physics department and research faculty have been an integral part of LIGO since 2007,” Chancellor Jeffrey S. Vitter said. “It is quite an honor for the University of Mississippi to play a role in this international collaboration of talented scientists and engineers, which is producing such astounding breakthroughs and now the Nobel Prize in Physics.

“Our participation in this collaboration is a stellar example of UM’s transformative impact upon our understanding of the world.”

The Royal Swedish Academy of Sciences, founded in 1739, is an independent organization whose overall objective is to promote the sciences and strengthen their influence in society. The academy takes special responsibility for the natural sciences and mathematics, but works to promote the exchange of ideas between various disciplines. Nobel Prize is a registered trademark of the Nobel Foundation.