Do black holes regulate the growth of massive galaxies?
Lead Research Organisation:
University of Hertfordshire
Department Name: School of Physics, Astronomy and Maths
Abstract
This project will exploit data from the James Clerk Maxwell Telescope (JCMT) Cosmology Legacy Survey (S2CLS)
to investigate the link between accretion on to black holes and the formation of massive galaxies in the early Universe.
The S2CLS is the largest of the JCMT Legacy Surveys and is providing the first samples of thousands of extragalactic
sources selected in the submillimetre (submm) wavebands, an order-of-magnitude improvement in the
sample sizes of previous surveys at these wavelengths.
The submm atmospheric window allow us to access the redshifted far-infrared emission
from high-redshift galaxies and active galactic nuclei (AGN) thus pin-pointing intense star -formation activity in the early Universe associated with the assembly of massive galaxies and black holes. Black holes are thought to play a key role in the galaxy formation process by regulating the growth of the stellar spheroid via a feedback process, i.e. a powerful wind from the accretion disk. Recent controversy in this field has come from studies with conflicting results. One high profile study claims that vigorous star formation is not observed in AGN with the highest accretion activity but is present in lower luminosity AGN. In contrast, a competing study finds no dependence of star-formtion rate on acretion activity. The former claim their result is evidence that luminous AGN suppress star formation while the latter conclude that no such claim can be made...a debate that is ongoing! The proposed project will use the unique characteristics of the S2CLS dataset to improve on previous studies and answer the question posed in the title...'Do black holes regulate the growth of massive galaxies?'
to investigate the link between accretion on to black holes and the formation of massive galaxies in the early Universe.
The S2CLS is the largest of the JCMT Legacy Surveys and is providing the first samples of thousands of extragalactic
sources selected in the submillimetre (submm) wavebands, an order-of-magnitude improvement in the
sample sizes of previous surveys at these wavelengths.
The submm atmospheric window allow us to access the redshifted far-infrared emission
from high-redshift galaxies and active galactic nuclei (AGN) thus pin-pointing intense star -formation activity in the early Universe associated with the assembly of massive galaxies and black holes. Black holes are thought to play a key role in the galaxy formation process by regulating the growth of the stellar spheroid via a feedback process, i.e. a powerful wind from the accretion disk. Recent controversy in this field has come from studies with conflicting results. One high profile study claims that vigorous star formation is not observed in AGN with the highest accretion activity but is present in lower luminosity AGN. In contrast, a competing study finds no dependence of star-formtion rate on acretion activity. The former claim their result is evidence that luminous AGN suppress star formation while the latter conclude that no such claim can be made...a debate that is ongoing! The proposed project will use the unique characteristics of the S2CLS dataset to improve on previous studies and answer the question posed in the title...'Do black holes regulate the growth of massive galaxies?'
Organisations
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| ST/N504105/1 | 01/10/2015 | 31/03/2021 | |||
| 1874143 | Studentship | ST/N504105/1 | 01/10/2016 | 30/04/2020 | Joanna Ramasawmy |
| Description | "Universe Unseen" talk and panel discussion |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Public/other audiences |
| Results and Impact | I was one of three researchers invited to speak at an event marking the launch of a new season at the Royal Observatory Greenwich, entitled "Universe Unseen". Around 80 members of the public attended the series of talks and panel discussion. |
| Year(s) Of Engagement Activity | 2018 |
| URL | http://www.rmg.co.uk/see-do/exhibitions-events/universe-unseen |
| Description | Astrobites regular contributor |
| Form Of Engagement Activity | Engagement focused website, blog or social media channel |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Undergraduate students |
| Results and Impact | The postgraduate student run blog Astrobites posts short, readable summaries of recent research papers in Astrophyics every day, aimed at an audience with undergrad-level physics knowledge. As a contributing author I have written 13 articles for the site, including interviews with researchers, conference summaries and comments on policy. Our most recent readership survey showed that our audience consists largely of undergraduate students, postgraduate students and amateur enthusiasts, and the site content is actively used in universities for undergraduate assignments. |
| Year(s) Of Engagement Activity | 2018,2019,2020 |
| URL | http://astrobites.org |
| Description | Festival outreach with planetarium |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Public/other audiences |
| Results and Impact | The university's large portable planetarium visited a number of music festivals, at which I gave presentations on my research. |
| Year(s) Of Engagement Activity | 2017,2018,2019 |
| Description | Planetarium presenter |
| Form Of Engagement Activity | Participation in an open day or visit at my research institution |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Schools |
| Results and Impact | Students attending the University of Hertfordshire open day were invited to watch a show in our portable planetarium. I presented a number of shows and answered questions. I have also given talks on my research at observatory open evenings. |
| Year(s) Of Engagement Activity | 2018,2019,2020 |
| Description | STFC Astronomer at Royal Observatory Greenwich |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Schools |
| Results and Impact | As the STFC Astronomer at the Royal Observatory Greenwich I deliver masterclasses on astrophysics, careers in STEM and my PhD research to secondary school groups as part of the museum's formal learning programme. Each week there are up to 4 masterclasses for up to 30 students in each group. |
| Year(s) Of Engagement Activity | 2017,2018,2019 |
| URL | http://www.rmg.co.uk/schools-communities/schools/royal-observatory/programmes |
| Description | School planetarium visits |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Schools |
| Results and Impact | I have been involved in running a programme of taking a portable planetarium into school classrooms, on a number of visits. An average visit reaches 80 children. |
| Year(s) Of Engagement Activity | 2018,2019,2020 |