Understanding Blazar Jets - The OVRO 40-m Blazar Monitoring Program

Lead Research Organisation: University of Manchester
Department Name: Physics and Astronomy

Abstract

The project is centred round the radio monitoring of 1500 Blazars with the 40-m telescope at the Owens Valley Radio Observatory (OVRO, California, USA) and then producing a joint analysis with Fermi gamma ray data. Blazars are powered by accretion onto rotating super-massive black holes which create relativistic jets along the spin axis, though the detailed mechanism of this process still remains elusive. The jets in Blazars are aligned at a small angle to the line of sight, with the result that relativistic beaming dramatically boosts the apparent luminosity and variability. One avenue for progressing our understanding of jet production is provided by the Fermi Gamma-ray Space Telescope, which continuously monitors all gamma-ray bright Blazars, allowing an unprecedented opportunity for the systematic study of Blazar jets. The exact location of the gamma-ray emission region and its proximity to the central black hole remain subjects of debate, with two main competing classes of models for the GeV emission region. Testing these models requires a multiwavelength approach, combining the Fermi observations with supporting radio observations from OVRO-40m to search for correlations in the light curves at different frequencies.

Publications

10 25 50

Studentship Projects

Project Reference Relationship Related To Start End Student Name
ST/P006795/1 01/10/2017 30/09/2024
2025713 Studentship ST/P006795/1 01/10/2017 31/03/2022 Thomas Mcaloone
 
Description Owen's Valley Radio Observatory Collaboration 
Organisation California Institute of Technology
Department Caltech Owens Valley Radio Observatory
Country United States 
Sector Public 
PI Contribution My PhD has focused on identifying events in OVRO 40m blazar light curves. By conducting my research, I aim to produce software capable of identifying the events automatically, which then will allow further science to be done to investigate any events found - which offers value to OVRO.
Collaborator Contribution OVRO provides access to the data from their 40m blazar monitoring program as well as discussion, assistance and advice on the direction of my research. I was also invited to work with my collaborators out in Caltech and at the OVRO site for several weeks towards the end of 2018.
Impact The main outputs of the collaboration will be the Idenfitication procedure I develop, as well as my PhD Thesis. Neither has been completed yet.
Start Year 2017
 
Description Research collaboration to develop a Transdimensional Nested Sampling algorithm 
Organisation University of Cambridge
Country United Kingdom 
Sector Academic/University 
PI Contribution With guidance from my supervisor, I have been developing protoype software to implement a 'transdimensional' variant to the standard Nested Sampling algorithm.
Collaborator Contribution We have been working with Dr Will Handley (University of Cambridge) and Dr Malak Olamaiet (York St John University) on the development of our novel algorithm.
Impact We have an algorithm which works reasonably well within certain limitations. After a little more work, we intend to publish our work so far to allow for input from the wider scientific community.
Start Year 2020
 
Description Research collaboration to develop a Transdimensional Nested Sampling algorithm 
Organisation York St John University
Country United Kingdom 
Sector Academic/University 
PI Contribution With guidance from my supervisor, I have been developing protoype software to implement a 'transdimensional' variant to the standard Nested Sampling algorithm.
Collaborator Contribution We have been working with Dr Will Handley (University of Cambridge) and Dr Malak Olamaiet (York St John University) on the development of our novel algorithm.
Impact We have an algorithm which works reasonably well within certain limitations. After a little more work, we intend to publish our work so far to allow for input from the wider scientific community.
Start Year 2020
 
Title SKA Mid Sensitivity Calculator Prototype 
Description During my 6-month placement at SKAO, I developed a prototype sensitivity calculator for the SKA-Mid array. 
Type Of Technology Webtool/Application 
Year Produced 2020 
Impact The calculator will be an extremely useful tool, both internally for SKA scientists and engineers, but also externally for the astronomy community. The calculator is to be handed over to another team to continue development of the software - likely working it into a larger observing tool to help researchers submit observation proposals for the SKA once it is operational. 
 
Description ScienceX 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact I volunteered at the JBCA booth at the ScienceX festival in 2018. The festival focuses on engagin the general public with scientific research at the University of Manchester. At the JBCA booth, I spent most of my time demonstrating a Virtual Reality simulation of the Milky Way galaxy, as seen from Earth, at various different wavelength across the electromagnetic spectrum.

The main impacts I noticed was from parents asking about how to get their children more involved and enaged with science.
Year(s) Of Engagement Activity 2018
URL https://www.mub.eps.manchester.ac.uk/sciencex/