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2020 January 22: Galaxy Luminosity Functions with 4 million galaxies out to redshift z~3

Thibaud’s luminosity functions paper goes on arXiv (click here). This work presents the best, most precise to date measurement of the rest-frame UV and U-band luminosity functions and their evolution from z~3 to z~0. In it we use 4 million (!!) galaxies to measure both the bright and faint ends of the LF simultaneously.

In this work we use our CLAUDS+HSC data to show that the shape of the UV luminosity function is remarkably stable, and that the evolution of the cosmic UV luminosity density (which we also measure) is driven almost entirely by the change in M*, the characteristic brightness of the galaxy population out to at least z~1.

more on CLAUDS...

2020 February 28: Clustering of ultra-massive dead monsters at cosmic noon -- paper accepted by MNRAS

Gurpreet’s paper on the clustering of ultra-massive quiescent galaxies at z~1.6 is accepted for publication in MNRAS. In this work we find that these objects are associated with very massive dark matter halos that are likely to evolve into present-day massive galaxy clusters like Virgo and Come.

You can see the advance-access version of the paper in MNRAS by clicking here.

2020 March 18: The environments of dead monsters at cosmic noon -- paper accepted by MNRAS

Our paper on the environments of ultra-massive passive galaxies (UMPEGs) at Cosmic Noon was accepted for publication in MNRAS. In this work, we show that these dead monsters are lonely: on average, they have very few massive satellites, which indicates that they formed through major mergers at earlier times. Combined with previous papers by Liz and Gurpreet (here and here), our analysis indicates that the UMPEGs are main-branch progenitors of some of the present-day Brightest Cluster Galaxies (BCGs) that first assembled through major mergers and then grew through minor mergers to become the central galaxies of massive clusters like Coma and Virgo.

2020 May 18: AGN hardness ratios in green valley galaxies -- paper accepted by MNRAS

Thibaud’s paper on the slow quenching of M* galaxies is accepted for publication in MNRAS. This work combines optical and X-ray data to investigate how galaxies behave as they cross from the blue cloud, through the green valley, and into the quenched red sequence. Using x-ray hardness ratios, which tells us about the environment of their central black holes, we find that massive green valley galaxies show indications that the quenching process is related to galaxy-galaxy mergers. This is consistent with a scenario in which the interaction between the galaxies’ parent dark matter halos during the merger perturbs their spin axes, thereby disrupting the flow of gas feeding them from the cosmic web. This then then leads to the (slow) quenching of their star formation.

The paper will be appearing in MNRAS soon. In the meantime you can see the advanced version on arXiv here.

2020 July 24: GIRMOS has a logo!

Check out the beautiful new official logo for the GIRMOS instrument on the left!

GIRMOS is a next-generation instrument now under development for the 8-metre Gemini observatory. GIRMOS will take AO-assisted spatially-resolved spectroscopy for up to four objects simultaneously, making it possible to carry out very large surveys and detailed surveys of objects in the distant Universe. Our role in the project is to develop the GIRMOS observation planning and data reduction software packages. To find out more about GIRMOS, click here.

2020 August 13: Angelo defends his MSc thesis!

Congratulations to Angelo for successfully defending his MSc thesis today! Angelo’s thesis, which was supervised by Ivana Damjanov and me, was on the evolution of morphologies of galaxies since z~0.9 in the field and in clusters. Only some minor corrections remain to do, and then Angelo’s off to officially start his PhD with us this September. Well done Angelo!

2020 October 7: The ICA annual report is out

The 2019-20 ICA annual report is out. The report describes the range of research activity undertaken by Institute members over the past year, from stellar atmospheres to galaxy evolution, and things in between. Find out what it is that we do by clicking on the image to the left!

2020 October 1: Nick joins the CANUCS team

Dr. Nick Martis, recently of Tufts University, joins the CANUCS JWST GTO team. Nick is an expert on galaxy evolution and his SMU position will be located at NRC Herzberg in Victoria. Welcome to the project, Nick!

2020 November 20: Group photo

COVID or not, it’s important to keep meeting to discuss science not just one on one but also as a group. Extragalactic observers at SMU do that twice a week: on Tuesdays we talk about the latest literature and on Fridays we share updates on our ongoing research. And today we managed to remember to take a group photo - here it is. ( Clockwise from top left: Gaël, Marcin, Lingjian, Kamalpreet, Harrison, Ophelie, Angelo, and - in the centre - Ivana. )

Click on the image to expand.

2020 December 4: JWST postdoc positions

I am looking for two outstanding young astronomers to join our 200-hour “CANUCS” Guaranteed Time Observer program on JWST. These fellows will focus on preparing for, processing, and analyzing JWST CANUCS data on distant galaxies behind five gravitationally-lensing clusters (including Abell370, seen in the HST image above; credit: NASA). The job ad can be found on the AAS job register here. Applications are due by 2021 January 8.

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