Published: April 21, 2021
Publication: Astrobites
Author: Tommy Wen Chin

Tommy Wen Chin is a 4th year undergraduate student at San José State University and a Cal-Bridge scholar. He conducted this research with Dr. Steven Furlanetto at UCLA as part of a Cal-Bridge REU and presented it as a poster at AAS2021.

During the epoch of reionization, ionizing photons from early galaxies carved out large ionized bubbles in the neutral intergalactic medium, which grew and eventually filled the Universe by about a billion years after the Big Bang. Over the next decade, using instruments like the Hydrogen Epoch of Reionization Array (HERA), astronomers hope to image the neutral regions remaining at the end of reionization using the 21-cm line. They hope to observe the state of the universe in this last unexplored phase of cosmic evolution to discover what objects first lit up the universe and how and when the first galaxies formed.

Unfortunately, although there are many models describing how ionized bubbles grow during reionization, there is little understanding of how the sizes of remnant neutral regions depend on astrophysical parameters, even though they are closely related problems.

We produced semi-numerical simulations of the neutral regions using 21cmFAST, which can be seen in Figure 1. We developed a Gaussian sphere method to measure the sizes of these regions and study their dependence on various astrophysical parameters. We then compared our results to other publicly available methods, specifically the mean-free-path (ray-casting) and friends-of-friends (percolation) methods. We found good agreement between these three methods at a constant overall neutral fraction, <x_HI>. However, the Gaussian sphere approach is much more similar in principle to the method of HERA’s observation.

Using these methods, we explored how specific astrophysical parameters affect the neutral region sizes after controlling for <x_HI>. Specifically, we investigated the overall ionizing efficiency of galaxies, ζ, and the horizon over which ionizing photons propagate, R_max. Figure 2 shows results of the Gaussian sphere method applied to the simulation data shown in Figure 1. A previous step in the Gaussian sphere algorithm determines the characteristic curve shape that corresponds to the typical size of the neutral regions (plotted in bold in Figure 2).

Published: September 23, 2020
Publication: Audible
Author: Excelencia in Education and Dra. Michelle Espino Lira

Listen to the podcast, here.

Published: October 1, 2019
Publication: Excelencia in Education
Author: n/a

Published: May 13, 2019
Publication: CSUN Today
Author: Carmen Ramos Chandler

A record 11,627 students are eligible to graduate from  California State University, Northridge this year. Each journey to that degree is as unique as each student, as are their destinations once they leave CSUN.

Some are headed to overseas to realize childhood dreams of professional sports careers. Others are headed into business, law school or teaching. Some are even have plans that could change our understanding of the universe. Below are just some of their stories:

Justin Bracks, B.S. in Astrophysics

Justin Bracks, 31, of Pasadena, will be spending the next several years building a balloon-bourn telescope that will launch several million dollars worth of equipment into the stratosphere from a research station in Antarctica, in an effort to get a better understanding of our universe.

“The telescope will spend several months floating over Antarctica, gathering data. When it lands we’ll have to trek out to wherever it ends up and retrieve our data” said Bracks, who will be doing that research as a doctoral student in astrophysics at the University of Pennsylvania, which has offered him a fellowship to cover the costs of the six years it will take him to get his Ph.D.

The University of Pennsylvania and Antarctica are a far cry from Compton, where he lived as a young child. He started teaching percussion in high school as a way to make money. Once he graduated, he continued working as a musician. When jobs became scarce during the 2008 recession, a friend connected him with a position at a dance studio. When he got a call offering him the job, he almost turned it down.

“But I hadn’t eaten for two days and there was nothing in my refrigerator,” he said. “Hunger can be an amazing motivator.”

Bracks turned that job into a 10-year career as one of Southern California’s leading ballroom dancers and instructors. He designed and launched his own after-school dance program for disadvantaged children, and he opened his own dance studio in Pasadena. A chance conversation a few years ago with one of his dance students, a scientist, ignited his interest in physics.

He enrolled at Moorpark College to get the academic foundation he needed to study the subject and then transferred to CSUN in 2017. He chose CSUN because of physics professor Farisa Morales, who also taught at Moorpark.

“If you have someone willing and able to help you, that you genuinely enjoy being around, you go where they are instead of a world where nobody necessarily likes you and nobody necessarily wants to help you,” Bracks said.

He admitted that transitioning from successful business owner to college student took some adjustment. He didn’t turn his business over to his partner until his junior year at CSUN.

“I went from a sea of extroverts — artists, dancers, writers and actors who were all willing to explore emotionally — to a sea of introverts,” he said. “Introverts often think the worst of people, if only to protect themselves. During my time here, I’ve really been forced to take the introvert’s perspective. I have been forced to listen more. I have learned to survive in a much lower energy environment. Astrophysics and the people I study and work with within astrophysics have made me a more thoughtful person.”

Bracks said he enjoys and looks forward to the challenges astrophysics present him.

“Physics is not intrinsically fun and exciting,” he said. “You are not going to sweaty and get an endorphin high afterwards.

“When I spent 14-hour days as a dancer, at least I got that. Fourteen-hour days working on physics, all you get is anxiety,” he joked.

“Dance was never something I wanted to do; it was something I ended up doing,” he said. “I learned and grew so much during my decade as a ballroom dancer. One of the things I learned and have taken with me is that hunger is an unbelievable, powerful motivator. I am proud of the work I did. But I was not as proud of that as I am of building radio antennas and balloon-born telescopes. Leaving something to do something else that I had never known, that is what I am tremendously proud of.”

Bracks is expected to take part in the College of Science and Mathematics’ commencement ceremony at 6 p.m. on Friday, May 17. 

Katharine Charnay, B.A. in Honors English

Katharine Charnay admits her journey to CSUN was not a direct one. But along the way, she said, she has learned that she is stronger than she thought and how to turn her mistakes into lessons on which she can build.

“Failure can be used as a tool for learning. You can’t let it define your success,” she said. “You can’t let mental illness define your success. In order to succeed, you need to fail. I have learned from my mistakes, and have grown from them.”

When the 29-year-old Porter Ranch resident graduated from high school more than a decade ago, she headed to Portland State University in Oregon for college.

“But I became really homesick,” she said. “I was having a hard time. So, I came home.”

She ended up going to Santa Monica Community College, where she earned an Associate of Arts degree in liberal arts. With that degree under her belt, she enrolled at CSUN in 2014, eager to start work on a bachelor’s degree.

“I grew up down the street from the school and knew that it was a place where I would be intellectually challenged and satisfy my curiosity to learn about everything under the sun,” she said.

Before she could get fully immersed in her classes, Charnay had to take a medical leave from school to address her struggles with depression and anxiety. When she returned in spring 2017, she was nervous. She reached out to a couple of faculty members to share her concerns.

“What I found was a community that was supportive and that would help me thrive,” she said.

As she settled into the university, she joined a variety of clubs and groups, including the University Ambassadors, through which she volunteered at university events and served as a campus tour guide. While she walked backward and pointed out important buildings on campus, Charnay would share her experiences at CSUN, including her own journey to the campus, and answer questions. She also got a part-time job on campus as a supplemental instructor for freshman English composition classes.

To alleviate stress, she attended open-mic nights at local comedy clubs, where she would turn classroom and life faux pas into a comedy routine.

“I found that I enjoy speaking in front of large groups of people,” she said. “At first, I am nervous, but I enjoy getting people to laugh at something that I found very embarrassing.”

Charnay enrolled at CSUN with the intent of studying psychology. She changed her major a couple times before settling on English because it was “something where I could practice my writing and persuasion abilities. I could learn about different subjects and apply that knowledge,” she said.

She plans to take those skills with her to law school this fall. She is currently weighing offers from four schools. She said she expects to make a decision in a couple of weeks. A factor in her decision is her father, John Charnay, who died earlier this year of prostate cancer. Charnay said he was among her biggest champions. She said he believed in her ability to make a positive difference in people’s lives. She said she hopes to do that as a lawyer.

Charnay is expected to take part in the College of Humanities’ commencement ceremony at 8 a.m. on Monday, May 20. 

Marissa Favela, B.S. in Public Health

When Keith West, head coach of CSUN’s women’s soccer team, looks at Marissa Favela, 21, he said, he sees courage, strength, tenacity, a dedicated student and a talented athlete who, when faced with obstacles, never gives up and has chosen to live life to the fullest.

Favela said West’s faith in her has inspired her to pursue her dreams of playing for a professional soccer team. She hopes to play for a team in London, England. Teams there have a program that would allow her to pursue a graduate degree in nursing while she plays. She won’t know if she got into the program until this summer.

Favela first played soccer at age 5, when her parents enrolled her in an American Youth Soccer Organization team in Diamond Bar, where she grew up. The sport soon became a passion. She spent as much time as possible on the field practicing. She played on club teams and was a member of the Diamond Bar High School girls team.

Her life took an abrupt turn at the start of her junior year of high school, when she was diagnosed with ovarian cancer. Her treatments curtailed her ability to practice and play soccer, and forced her to be temporarily homeschooled while she focused on her health.

When she returned to school at the end of her senior year, Favela said, she didn’t have the same body that had made her a star player in earlier years. She thought the opportunity to be scouted by college recruiters, which usually takes place during the junior year of high school, was gone.

“But somehow Coach West saw me, and he gave me a chance,” Favela said.

West happened to spot Favela playing a game in March of her senior year. He was struck by her natural talent. He said he talked to her high school coach to learn why she hadn’t already received offers from other schools and decided to give her a chance to play for CSUN. Favela enrolled at CSUN that fall, in 2014.

She said the transition to college life was “a little bit of a culture shock.”

“It’s a big school, and I was living on my own for the first time,” she said. “But as I look back, I realize it was a good experience.”

Favela admitted she struggled a little her first year at CSUN. She did not play much as she worked to get her body into shape for Division I play. She also had to adjust to the academic demands of being a public health major.

“Given my own experience with the healthcare industry, I knew that’s what I wanted to study,” she said, noting that her diagnosis of ovarian cancer at age 15 put her in a unique situation. She wasn’t “a kid with cancer,” nor was she an adult.

“I want to be a nurse who specializes in working with someone like me — who wasn’t a kid and wasn’t an adult — because I think teens sometimes get lost in the system,” she said.

She was determined to succeed, both in the classroom and on the pitch. She put in extra hours, in addition to regular practices, to hone her skills. She took advantage of tutoring and advisement programs offered by Matador Athletics to ensure she kept her grades up.

Over the past four years, she managed to successfully juggle the demands of her classes while being considered one of the top scorers in the Big West Conference. She helped CSUN advance to the 2017 Big West Tournament Championship game, was invited to be part of the All-Big West team and is currently eighth in CSUN history in scoring. She also has been cancer free for nearly six years.

Favela is expected to take part in the College of Health and Human Development’s  commencement ceremony at 6 p.m. on Monday, May 20.

Oshae C. Rodgers, B.A. in History, with a minor in Africana Studies

Oshae C. Rodgers, 21, of North Hollywood, is an ardent believer in appreciating history — your personal history, that of your community and that of the greater society.

“A lot of times, we’re learning the narrative of a homogeneous community,” Rodgers said. “But when you’re in high school or in middle school, you want to know ‘my’ narrative. You want to know about people ‘who look like me.’

“If I don’t know my history, then I truly don’t know my soul. Then I cannot understand how we all connect, because everything that happened before is influencing things now,” he said. “If we want to understand now and how to move forward, then we need to understand the past.”

Rodgers plans to turn that passion for history into a teaching career, first at a middle or high school and eventually a college. He recognizes that being a teacher is not easy, ‘but if I can touch just one life, and they go on and touch another life, then my job is done,” he said.

Passion for knowing about the past runs in his family. His grandfather Kenneth W. Rodgers, Sr., wrote about the experiences of his friends and family as urban African Americans in the 1960s and ‘70s in the book “Not My Shadow: A True African American Story.” His uncle, Kenneth Rodgers, teaches history, among other subjects, at Synergy Quantum Academy in South Los Angeles.

His uncle holds a special place in Rodgers’ heart. Rodgers grew up in an impoverished neighborhood in Albuquerque, New Mexico. By the time he reached his senior year in high school, things were rocky at home and he ended up camping out in a sleeping bag in a store room.

His uncle, hearing about his plight, invited Rodgers to live with him in North Hollywood. His only demands: Rodgers continue his education and get a job. Before he left Albuquerque, Rodgers met with a high school counselor who implied he had too many strikes against him to succeed in college.

Rodgers was 17 and just months shy of his high school graduation when he arrived in California. Determined to get his diploma on time, he crammed more than a year of studies into just a few months of night classes to meet California’s high school graduation requirements.

He also toured local college campuses, including CSUN.

He felt “like a number” on some of the tours, he said, “but when I got to CSUN, someone sat down with me and said ‘Let’s look at your credits here and in Albuquerque, and see how we can get you into CSUN.’ It was very personal, and I immediately knew I was home.”

Rodgers enrolled at CSUN in 2014 and threw himself into his studies, reveling in the intellectual exchanges with his peers and professors. He was named a University Scholar, part of a cohort of academically achieving students. In 2016, he received a CSU Trustee Award for Outstanding Academic Achievement for demonstrating superior academic performance, personal accomplishments, community service and financial need. He also started writing a book, a semi-memoir that he hopes will serve as inspiration for other young people.

Rodgers starts graduate school in the fall at UCLA, where he will be working on a master’s in education, with an emphasis in social justice, as well as a teaching credential. But first, he plans to return to Albuquerque this summer for a family graduation celebration. While there, he plans to visit a certain high school counselor who doubted his college dreams.

Rodgers is expected to take part in the College of Social and Behavioral Sciences’ commencement ceremony at 8 a.m. on Saturday, May 18.

Argin Yadegarian, B.S. in Accounting

Argin Yadegarian, 30, of Glendale, hasn’t received his diploma yet, but he is already making plans to give back to the institution that he credits with helping him achieve his dreams.

He is thinking about creating a scholarship at CSUN, once he’s established himself as a businessman, to ensure that future students like him — an immigrant from a low-income family — have the support and encouragement they need to succeed.

“It’s been on my mind for a while,” he said. “I’m not just going to let it lie. I will make sure it happens.”

Yadegarian was 17 and living in his native Iran when his father died. Shortly thereafter, his brother, who is 10 years older and had studied engineering, moved to the United States for a job. It fell on Yadegarian’s shoulders to support himself and his mother. He found a job as a lifeguard and taught swimming to young children.

“I loved working with young children, but I dreamed of going to college and working in business,” he said. “That wasn’t possible in my home country. We just didn’t have the money or connections.”

After his brother took a job in the California, he offered to bring Yadegarian and their mother to the U.S. That was six years ago.

Yadegarian was determined to take advantage of the opportunities his new home presented. He enrolled at Glendale Community College to learn English and then took the classes necessary to transfer to a four-year institution to study accounting.

“Accounting is the language of business,” he said. “If you want to be successful in the world of business, you need to read a financial statement and know how the business works at its core. Accounting is the foundation of all that.”

He chose CSUN, he said, because its Department of Accounting is considered one of the best in the state.

From the start, he said, he found a supportive environment at the university — from the staff in the David Nazarian College of Business and Economics’ Educational Opportunity Program (EOP) to classmates in the college’s business fraternity, Beta Alpha Psi, fellow volunteers at CSUN’s Volunteer Income Tax Assistance (VITA) Clinic, and faculty in the accounting department. Someone was always willing to help him navigate any obstacle he encountered.

A chance conversation with CSUN accounting alumnus Charles Noski and his wife, Lisa, at a university dinner in 2017 led to a scholarship that covered Yadegarian’s educational expenses during his time at the university. His eyes teared up as he recounted the story.

“It was just so very huge in my life,” said Yadegarian, who cares for h is ailing mother when he is not at school. “I am an immigrant. I come from a low-income family. And I can go to college because someone believed in me and gave me the financial support so that I could go through the program. I am truly grateful for what the Noskis have done for me. I cannot thank him enough for believing in me. What I can do is pay it forward. To let someone else like me know that there are people who believe in them.”

Yadegarian has a job waiting for him with the international professional services firm Ernst & Young when he graduates. He is expected to take part in the commencement ceremony for the David Nazarian College of Business and Economics at 8 a.m. on Sunday, May 19.

Published: October 1, 2018
Publication: UC Santa Cruz News Center
Author: Tim Stephens

Cal-Bridge program receives $5 million grant for Ph.D. pathways at 24 campuses

UC Santa Cruz is part of a consortium of nine UC and 15 California State University campuses collectively awarded a five-year, $5 million grant from the National Science Foundation to dramatically increase diversity in physics and astronomy through the Cal-Bridge program.

Launched four years ago in Southern California, the Cal-Bridge program creates a pathway for students from multiple CSU campuses to Ph.D. programs in physics and astronomy at UC campuses across California. Last year, the program began a small-scale expansion into Northern California, with UC Santa Cruz and San Jose State University leading the effort.

“This new grant allows us to ramp up the program substantially,” said Bruce Schumm, professor of physics at UC Santa Cruz, who leads the the Northern California Cal-Bridge program along with principal investigator Aaron Romanowsky, an astronomer at San Jose State University.

“This program knits together the three branches of the California higher education system by identifying promising physics and astronomy students within the broadly diverse CSU and community college systems and connecting them to a strong mentoring and professional development network,” Schumm said.

Currently, students from underrepresented minority groups represent 30 percent of the U.S. population but less than 4 percent of physics and astronomy Ph.D.s awarded nationwide. The Cal-Bridge program aims to have a national impact on the number of students from underrepresented groups graduating with a physics degree and matriculating to Ph.D. programs in physics or astronomy.

The new grant allows Cal-Bridge to expand from about a dozen scholars per year to as many as 50 statewide. The national average of underrepresented minorities earning a Ph.D. in these fields is about 80 per year. Cal-Bridge is led by principal investigator and program director Alexander Rudolph, a Cal Poly Pomona professor of physics and astronomy.

Cal-Bridge scholars are recruited from the 15 CSU campuses and more than 30 community colleges in the Cal-Bridge network, with the help of local faculty and staff liaisons at each campus. Once selected, Cal-Bridge Scholars receive substantial financial support, intensive mentoring, professional development workshops, and exposure to a wide variety of research opportunities.

“We’re trying to identify students who are ‘diamonds in the rough,’ who show potential but might not stand out by the usual academic indicators,” Schumm said. “The goal is to get these students into graduate school and ultimately to bring more diversity into the ranks of physicists and astronomers in California and nationwide. Our new cohort was just here for a program on campus, and they are a diverse group of very impressive students.”

Every student has two faculty mentors, one at a CSU and one at a UC. A steering committee of CSU and UC faculty convenes several times a year to discuss each student in depth, providing important group feedback into the mentoring process.

“We lay out the path for them to get into graduate school, offer workshops for professional development and computing skills, and provide connections to summer research internships,” Schumm said.

The program has been highly successful in its first five years in developing a pipeline of highly diverse, qualified scholars, many of whom have already successfully matriculated to a Ph.D. program in physics or astronomy. The program just selected its fifth cohort of 27 scholars from 10 different CSU campuses across the state, bringing the total number of scholars to 61 in five cohorts, including 35 Latinos, seven African-Americans, and 27 women (16 of the 27 women are from underrepresented minority groups). In the last three years, 19 of 21 Cal-Bridge Scholars who have earned their bachelor’s degree in physics have begun or will attend Ph.D. programs in physics or astronomy at top programs nationally, including UC Irvine, UC Santa Barbara, Harvard University, Northwestern University, the University of Maryland, Michigan State University, and Penn State University.

Schumm said he hopes the Cal-Bridge program can serve as a model for programs to address diversity issues in other STEM fields and in other states.