News

Newly Minted PhD: Chao Shi

10 May 2017 John Wise Leave a comment

Last week, Chao Shi successfully defended his thesis, "The Dynamics of Black Holes in the First Galaxies". He joins Daegene Koh in graduating this year, receiving their PhDs. He'll be starting as a software research scientist at Pindrop, a voice fraud detection company based in Midtown Atlanta and founded by Georgia Tech … Continue Reading ››

News

New Paper: Stochastic Reionization from the Smallest Galaxies

1 May 2017 John Wise Leave a comment

Also last week, we submitted a paper, led by Pengfei Chen (now in the finance sector), on the stochastic nature of reionization during its initial phases. Here we used the galactic properties from the Renaissance Simulations as the source model in a reionization simulation. We find that before a redshift of 10 (age of … Continue Reading ››

News

New Paper: Turbulent accretion onto black holes

1 May 2017 John Wise Leave a comment

Last week, our paper (arXiv), led by KwangHo Park, on the behavior of accretion flows onto intermediate mass black holes was submitted to the Astrophysical Journal. Here we used 3D radiation hydrodynamics simulations to study how the surrounding environment is affected by radiation feedback that originates from the gas around the black hole. … Continue Reading ››

News

Newly minted PhD: Daegene Koh

27 Mar 2017 John Wise Leave a comment

Today, Daegene Koh successfully defended his PhD thesis! Congratulations! He is the first PhD student to defend out of my group. He's written two papers so far on the growth of magnetic fields around the first stars (arXiv) and extending reionization models to include the first stars and first galaxies (arXiv). He'll … Continue Reading ››

News

New Paper: Massive Black Hole Formation

14 Mar 2017 John Wise Leave a comment

Yesterday, our paper (free arXiv link), led by John Regan at the Dublin City University, on the formation of massive black holes in the early universe was published in Nature Astronomy. We investigated the "close-pair scenario" where a nearby nascent galaxy shines on a pre-galactic cloud, which destroys most of its … Continue Reading ››

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New Paper: X-ray Binaries during Reionization

11 Feb 2017 John Wise Leave a comment

Last week, we published a paper, led by Arpan Das at the Scuola Normale Superiore in Pisa, Italy, on high mass X-ray binaries and their impact on the 21-cm signal during cosmic reionization. Here we used the "Birth of a Galaxy" simulations to calculate how the host galaxy attenuates UV and X-ray … Continue Reading ››

News

New Paper: Mocking the First Galaxies for JWST

12 Jan 2017 John Wise Leave a comment

Yesterday, PhD candidate Kirk Barrow submitted his first (!) paper (arXiv), titled "First Light: Exploring the Spectra of High-Redshift Galaxies in the Renaissance Simulations". Correlations between physical and observational properties of the first galaxies are imperative to determine before JWST launches in October 2018. We have examined two of the most massive … Continue Reading ››

News

New Paper: The Grackle

10 Nov 2016 John Wise Leave a comment

A couple of weeks ago, we submitted the method paper (arXiv) on Grackle, a chemistry and cooling library for astrophysical simulations and calculations, for publication. The paper is led by Britton Smith (now at UC-San Diego), and the code and documentary can be found here.

News

New Paper: AGORA Comparison Project, Isolated Galaxies

11 Oct 2016 John Wise Leave a comment

The AGORA Collaboration, primarily led by Ji-hoon Kim, aims to compare various computational astrophysics simulation code in several different tests. In our second paper (arXiv), we use the isolated disk galaxy as a test bed, comparing nine codes. Differences between the final results are small and are more dependent on the input … Continue Reading ››

Notes

A bash function to make movies

16 Sep 2016 John Wise 1 Comment

I use ffmpeg often to make and modify movies. But when creating movies from image sequences, ffmpeg requires the movies to be sequentially numbered. Some time ago, I wrote a bash function that create temporary symbolic links to the image files from which ffmpeg can create a movie. You can find the function below, and … Continue Reading ››

Computational Cosmology at Georgia Tech

Newly Minted PhD: Chao Shi

New Paper: Stochastic Reionization from the Smallest Galaxies

New Paper: Turbulent accretion onto black holes

Newly minted PhD: Daegene Koh

New Paper: Massive Black Hole Formation

New Paper: X-ray Binaries during Reionization

New Paper: Mocking the First Galaxies for JWST

New Paper: The Grackle

New Paper: AGORA Comparison Project, Isolated Galaxies

A bash function to make movies

Simulating the Universe