Caltech wasn’t the only SoCal school helping discover gravitational waves

From Caltech:
From Caltech: "The approximate location of the source of gravitational waves detected on September 14, 2015, by the twin LIGO facilities is shown on this sky map of the southern hemisphere. The colored lines represent different probabilities for where the signal originated: the purple line defines the region where the signal is predicted to have come from with a 90 percent confidence level; the inner yellow line defines the target region at a 10 percent confidence level. A small galaxy near our own, called the Large Magellanic Cloud, can be seen as a fuzzy blob underneath the marked area, while an even smaller galaxy, called the Small Magellanic Cloud, is below it."

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It was a Thursday and Caltech students and staff were partying with food, a photo booth and lots of smiling faces, but this wasn't a late night mixer. It was an early morning press conference.

Scores gathered at the Pasadena campus around 7:30 a.m. to watch a live feed beamed from Washington D.C. to a movie screen in an auditorium. On it, Caltech's David Reitze was speaking.

"Ladies and gentlemen... we have detected gravitational waves! We did it!" he said to thunderous applause.

Reitze is executive director of LIGO, the Laser Interferometer Gravity-wave Observatory, where the elusive -- and before now theoretical -- waves were recorded. But Reitze was just one in a cast of hundreds who helped prove a theory posited by Albert Einstein one hundred years ago.

Proving the existence of gravitational waves isn't just a victory for academics, but a milestone in humankind's understanding of how our universe came into being and continues to evolve.

Researchers from around the world contributed calculations, theories and equipment to the discovery. And on this day, each of them could take a well deserved ounce of pride for their participation in one of the biggest developments in physics in decades. Among them were students and staff at three Southern California schools: Caltech, USC and Cal State Fullerton.

One of them is CSUF undergrad student Conner Park, who helped model waveforms for the sorts of cosmic events LIGO could detect.

"It's really cool to be part of this," he said after a morning of celebrating with his classmates.

LIGO might never have happened if it weren't for Caltech and researcher Kip Thorne in particular.

In the early 1970s, Thorne read a paper by an MIT researcher named Rainer Weiss that described in detail how an interferometer might be used to hunt for gravitational waves.

A brief history of LIGO

In the past, interferometers had been used in many scientific fields like astronomy, seismology and oceanography, but Weiss gave a compelling argument for how one might be tuned to pick up subtle ripples in space and time.

Kip Thorne loved the idea and started talking with Weiss about how to pull this off.

In 1979, Caltech secured funds from the National Science Foundation to build a 40-meter prototype of Weiss' LIGO design as a sort of proof of concept.

"When it first came online, they could detect trucks on the 210 freeway," said Leslie Maxfield, director of academic media technologies at Caltech.

Still, it wasn't sensitive enough to pick up the super-subtle vibrations of a gravitational wave, a force so faint it would only move an object one-ten thousandth the width of a proton. For that, you'd need a much larger LIGO.

So in 1989, Caltech and MIT asked the National Science Foundation to help fund a pair of four-kilometer LIGOs. Three years later, the money was approved and construction soon began at a site in Hanford, Washington, and another in Livingston, Louisiana.

These locations were chosen in part because they were remote making them less likely to pick up unwanted vibrations.

"We put them far away from Southern California because Southern California, let's face it, is a noisy place," explained Caltech professor and LIGO researcher Alan Weinstein.

Much of the electronics for the LIGO facilities were built by Caltech engineers and key elements were designed on campus.

The initial designs weren't sensitive enough to pick up gravitational waves, so the team used lessons learned and began rebuilding the detectors from the ground up.

In 2015, the so-called Advanced LIGO went on line and soon it felt it's first rumbling of a wave in September.

Caltech researcher Surabhi Sachdev helped come up with theories for what kind of astronomical phenomenon might have caused the reading. In particular, she modeled what kind of reading to expect from the merging of two black holes in a distant galaxy.

It turned out, that model was the best at explaining the waves detected here on Earth.

Sachdev says she was thrilled, but the team had to keep it secret for months while they double-checked their work.

"It was hard because you know you wanted to tell your friends and your family, but we also wanted to be absolutely sure that we are not making any mistakes before we tell people about it," she said.

"So we just kept quiet."

The sound of two black holes merging

When the news finally broke several months after that initial detection, it wasn't just Caltech celebrating. A team at USC were also basking in the glow of a job well done.

"It's just incredibly thrilling to have a small part of this," said Ewa Deelman with USC's Information Sciences Institute.

Her team designed a program called Pegasus that helped LIGO researchers manage data and streamline workflow. That has came in handy since there were around a thousand researchers working on the project from around the globe, and they needed to share complicated information.

Meanwhile in Orange County, Cal State Fullerton students and staff were cheering their own contributions to what some are calling the discovery of the century.

"Everyone's just been caught up in the excitement of the day," said Jocelyn Read, an astrophysicist and professor at CSUF.

She and her colleagues helped identify unwanted noise in the LIGO signal, so an eventual reading of an actual gravitational wave could be detected.


(Cal State Fullerton professor Jocelyn Read and students Eric Flynn, Alyssa Garcia, Nick Demos, John Derby and Amy Feaster. They were part of the international team that helped detect gravitational waves.)

Fullerton might not be the first place that pops to mind when you think of deep-space science, but Read said the school made a concerted effort to change that by hiring her and two other gravitational-wave researchers in 2012.

"Cal State Fullerton took a bit of a risk hiring a whole group in gravitational-wave physics which was a little bit of a niche field," she explained.

Still, that risk paid off big now that the school can boast it was the only institution in Orange County involved in this groundbreaking project.

Several CSUF undergrad students also had a hand in the work, making meaningful contributions and getting a head start in their scientific careers.

But that doesn't mean they were able to slack off all day, said senior Conner Park. That afternoon he was already back at a desk tackling another problem: his homework.

"You know, we're students, and we have to also get our work done," he joked.