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Searching for Black Holes Born with Galaxies

Monday, October 1, 2018

Editors Note: This story by John Toon was originally published in the Georgia Tech News Center on Sept. 20, 2018. The headline was changed for the College of Sciences website.

Black holes form when stars die, allowing the matter in them to collapse into an extremely dense object from which not even light can escape. Astronomers theorize that massive black holes could also form at the birth of a galaxy, but so far nobody has been able to look far enough back in time to observe the conditions creating these direct collapse black holes (DCBH).

The James Webb Space Telescope, scheduled for launch in 2021, might be able look far enough back into the early Universe to see a galaxy hosting a nascent massive black hole. Now, a simulation done by researchers at the Georgia Institute of Technology has suggested what astronomers should look for if they search the skies for a DCBH in its early stages.

The first-of-its-kind simulation, reported September 10 in the journal Nature Astronomy, suggests that direct formation of these black holes would be accompanied by specific kinds of intense radiation, including X-rays and ultraviolet emission that would shift to infrared by the time they reach the telescope. The black holes would also likely spawn massive metal-free stars, a finding that was unexpected.

The research was supported by NASA, the Los Alamos National Laboratory, the National Science Foundation, the Southern Regional Education Board and two Hubble theory grants.

“There are supermassive black holes at the center of many large galaxies, but we haven’t been able to observe the way they form or how they got that large,” said Kirk S. S. Barrow, the paper’s first author and a recent Ph.D. graduate of Georgia Tech’s School of Physics. “Scientists have theorized that these supermassive black holes could have formed at the birth of a galaxy, and we wanted to turn these theoretical predictions into observational predictions that could be seen by the James Webb Space Telescope.”

DCBH formation would be initiated by the collapse of a large cloud of gas during the early formation of a galaxy, said John H. Wise, a professor in Georgia Tech’s School of Physics and the Center for Relativistic Astrophysics. But before astronomers could hope to catch this formation, they would have to know what to look for in the spectra that the telescope could detect, which is principally infrared.

The formation of a black hole could require a million years or so, but to envision what that might have looked like, former postdoctoral researcher Aycin Aykutalp – now at Los Alamos National Laboratory – used the National Science Foundation-supported Stampede Supercomputer at the University of Texas at Austin to run a simulation focusing on the aftermath of DCBH formation. The simulation used physics first principles such as gravity, radiation and hydrodynamics.

“If the galaxy forms first and then the black hole forms in the center, that would have one type of signature,” said Wise, who is the Dunn Family Associate Professor in the School of Physics. “If the black hole formed first, would that have a different signature? We wanted to find out whether there would be any physical differences, and if so, whether that would translate into differences we could observe with the James Webb Space Telescope.”

The simulations provided information such as densities and temperatures, and Barrow converted that data into predictions for what might be observed through the telescope – the light likely to be observed and how it would affected by gas and dust it would have encountered on its long journey to Earth. “At the end, we had something that an observer could hopefully see,” Barrow said.

Black holes take about a million years to form, a blip in galactic time. In the DCBH simulation, that first step involves gas collapsing into a supermassive star as much as 100,000 times more massive than our sun. The star then undergoes gravitational instability and collapses into itself to form a massive black hole. Radiation from the black hole then triggers the formation of stars over period of about 500,000 years, the simulation suggested.

“The stars of this first generation are usually much more massive, so they live for a shorter period of time,” Wise said. “In the first five to six million years after their formation, they die and go supernova. That’s another one of the signatures that we report in this study.”

After the supernovae form, the black hole quiets down but creates a struggle between electromagnetic emissions – ultraviolet light and X-rays trying to escape – and the black hole’s own gravity. “These cycles go on for another 20 or 30 million years,” Wise said.

Black holes are relatively common in the universe, so the hope is that with enough snapshots, astronomers could catch one being born, and that could lead to a new understanding of how galaxies evolve over time.

Star formation around the DCBH was unexpected, but in hindsight, it makes sense, Barrow said. The ionization produced by the black holes would produce photochemical reactions able to trigger the formation of the stars. Metal-free stars tend to be larger than others because the absence of a metal such as iron prevents fragmentation. But because they are so large, these stars produce tremendous amounts of radiation and end their lives in supernovae, he said.

“This is one of the last great mysteries of the early universe,” Barrow said. “We hope this study provides a good step toward figuring out how these supermassive black holes formed at the birth of a galaxy.”

This research was supported by a Southern Regional Education Board doctoral fellowship, a LANL LDRD Exploratory Research Grant 20170317ER, National Science Foundation (NSF) grants AST-1333360 and AST-1614333, Hubble theory grants HST-AR-13895 and HST-AR-14326, and NASA grant NNX-17AG23G. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the sponsoring organizations.

CITATION: Kirk S. S. Barrow, Aycin Aykutalp & John H. Wise, “Observational signatures of massive black hole formation in the early Universe,” (Nature Astronomy, 2018). https://doi.org/10.1038/s41550-018-0569-y

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Media Relations Contact: John Toon (404-894-6986) (jtoon@gatech.edu).

Writer: John Toon

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Summary: 

The first-of-its-kind simulation suggests that direct formation of these black holes would be accompanied by specific kinds of intense radiation, including X-rays and ultraviolet emission that would shift to infrared by the time they reach the telescope. The black holes would also likely spawn massive metal-free stars, a finding that was unexpected.

Intro: 

The first-of-its-kind simulation suggests that direct formation of these black holes would be accompanied by specific kinds of intense radiation, including X-rays and ultraviolet emission that would shift to infrared by the time they reach the telescope. The black holes would also likely spawn massive metal-free stars, a finding that was unexpected.

Alumni: 

Emergence of Collective Cognition in Animal Groups

Abstract

For over a century, researchers have been investigating collective cognition, in which a group of individuals together processes information and acts as a single cognitive unit. However, we still know little about the circumstances under which groups achieve better (or worse) decisions than individuals. To address this question my research applies concepts and methods from psychology to both individuals and groups in order to directly compare their cognitive abilities.

ScienceMatters Hall of Fame Welcomes Sachin S. Y. Kothandaraman

Wednesday, September 26, 2018

Once again, a Georgia Tech student ends up winning a ScienceMatters quiz because of the desire to take a homework break.

For Episode 4, it was Allie Caughman hearing the winning quiz detail during a study break. For Episode 5's quiz, Sachin Sarath Yadav Kothandaraman's need to relax a little resulted in the graduate student joining the ScienceMatters Hall of Fame.

"I heard this particular episode while I was taking a break from my assignments," Kothandaraman says. But it wasn't the first time he listened to the podcast. "I started listening to ScienceMatters after my classmate shared it with me. I've been hooked since."

Kothandaraman is from Chennai, India, where he received a bachelor's degree in biotechnology from Anna University. He is in his first year in the Georgia Tech Bioinformatics Graduate Program.

Continue here to the full story.

Media Contact: 

Renay San Miguel
Communications Officer
College of Sciences

Summary: 

Sachin Sarath Yadav Kothandaraman, a graduate student in the Bioinformatics Graduate Program, won the ScienceMatters Episode 5 quiz. Kothandaraman is researching machine-learning tools to predict drug responses to cancers in Fredrik Vannberg's lab.

Intro: 

Sachin Sarath Yadav Kothandaraman, a graduate student in the Bioinformatics Graduate Program, won the ScienceMatters Episode 5 quiz. Kothandaraman is researching machine-learning tools to predict drug responses to cancers in Fredrik Vannberg's lab.

Alumni: 

There's a Moth in My Video Game! Episode 6, Starring Simon Sponberg

Monday, September 24, 2018

Episode 6 of ScienceMatters' Season 1 stars Simon Sponberg.  Listen to the podcast here and read the transcript here!

Simon Sponberg, an assistant professor with joint appointment in the School of Physics and the School of Biological Sciences, loves to study how insects like moths and cockroaches move. The Georgia Tech professor discovers the physics and mathematics hidden within the biological systems of these creatures. And what he learns about animal locomotion could mean better robots, better prosthetic devices, and better vehicles.

Sponberg is the principal investigator in the Agile Systems Lab. He received a National Science Foundation's Faculty Early Career Development Award in 2016, and won the National Society for Neuroethology Young Investigator Award in 2014. Sponberg also researches at Georgia Tech's Parker H. Petit Institute for Bioengineering and Bioscience.

Take a listen at sciencematters.gatech.edu.

Enter to win a prize by answering the question for Episode 6:

According to Episode 6, what animal did Simon Sponberg study when he was an undergraduate in Lewis and Clark College, in Oregon?

Submit your entry by 11 AM on Monday, Oct. 1, at sciencematters.gatech.edu. Answer and winner will be announced shortly after the quiz closes.

Media Contact: 

Renay San Miguel
Communications Officer
College of Sciences

Summary: 

Simon Sponberg uses moths and cockroaches to study "the physics of living systems." With the help of virtual reality and video game principles, Sponberg's research into how animals move within their environments could lead to better robots, vehicles, and prosthetic devices.

Intro: 

Simon Sponberg uses moths and cockroaches to study "the physics of living systems." With the help of virtual reality and video game principles, Sponberg's research into how animals move within their environments could lead to better robots, vehicles, and prosthetic devices.

Alumni: 

Visualizing the Birth of Galaxies: Episode 5, Starring John Wise

Monday, September 17, 2018

Episode 5 of ScienceMatters' Season 1 stars John Wise. Listen to the podcast here and read the transcript here!

Possible scenarios for the birth of stars, galaxies, and black holes come alive in the data crunching and visualizations of John Wise, a professor in the School of Physics. Wise explains how his simulations and visualizations -- some of which have won awards -- helps researchers "rewind" space and time back to the origins of the universe.

Wise studies the intricacies of the nearby and distant universe, using state-of-the-art numerical simulations that are run on the world's largest supercomputers.

Wise won the College of Sciences' Eric Immel Award in 2015 for Excellence in Teaching. He was the recipient of the Dunn Family Professorship from 2015-2017, and was a NASA Postdoctoral Program Fellow from 2007-2009.

Take a listen at sciencematters.gatech.edu.

Enter to win a prize by answering the question for Episode 5:

What is the name of the University of Illinois supercomputer mentioned in Episode 5 that John Wise uses for visualizations and simulations?

Submit your entry by 11 AM on Monday, Sept. 24, at sciencematters.gatech.edu. Answer and winner will be announced shortly after the quiz closes.

Media Contact: 

A. Maureen Rouhi, Ph.D.
Director of Communications
College of Sciences

Summary: 

His visualizations of the heavens look like they are straight from Hollywood movie blockbusters. But John Wise's goal is to help researchers understand possible scenarios for the birth of stars and massive black holes. Wise talks about his research in ScienceMatters Episode 5.

Intro: 

His visualizations of the heavens look like they are straight from Hollywood movie blockbusters. But John Wise's goal is to help researchers understand possible scenarios for the birth of stars and massive black holes. Wise talks about his research in ScienceMatters Episode 5.

Alumni: 

Prof. O'Shea publishes new book

Monday, September 10, 2018
A listing for the text can be found at the SPIE Press Web site. The book was launched at a luncheon at SPIE’s Optics and Photonics conference in San Diego on August 22, 2018. 
 
The text demonstrates how to design an optical system using Synopsys CODE V, a full-featured optical design program. The complete design process (from lens definition to the description and evaluation of lens errors on to the improvement of lens performance) is developed and illustrated using the program.
 
This text is not a user’s manual for CODE V. Instead, it begins with a single lens to demonstrate the laws of optics and illustrates the basic optical errors (aberrations). Then, through a series of examples, demonstrations, and exercises, readers can follow each step in the design process to analyze and optimize the system for the lens to perform according to specifications. The text is organized to help readers (1) reproduce each step of the process including the plots for evaluating lens performance and (2) understand its significance in producing a final design.
Summary: 

Don O’Shea, Emeritus Professor of Physics, and and Dr. Julie L. Bentley of the Institute of Optics at the University of Rochester have published a text, Designing Optics Using CODE V.

Intro: 

Don O’Shea, Emeritus Professor of Physics, and and Dr. Julie L. Bentley of the Institute of Optics at the University of Rochester have published a text, Designing Optics Using CODE V.

Alumni: 

Public Lecture - Forecasting Turbulence

Fluid turbulence is one of the greatest unsolved problems of classical physics (and the subject of a million dollar mathematical (Millenium) challenge).  Centuries of research--including Leonardo da Vinci’s observations of “la turbolenza” and the best efforts of numerous physicists (Heisenberg, Kelvin, Rayleigh, Sommerfeld, ...)--have failed to yield a tractable predictive theory.  However, recent theoretical and computational advances have successfully linked recurring transient patterns (coherent structures) within turbulence to unstable solutions of the equations governing fluid flow (th

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