RIFP Post Doc profiles

RIFP Fellows are appointed across a very broad range of science areas – from studies of interstellar dust to development of new surfactant molecules for pharmaceutical or detergent uses. Here you can read about the researchers employed under the programme and their projects by clicking on their name. These pages for each Fellow are in the process of being created at the moment – the project titles for the first and second groups of Fellowships to be awarded are also available.

 

ASTeC

Sepideh Aliasghari

(Credit: Sepideh Aliasghari)

Copper supper conducting radio frequency (SRF) cavity preparation and deposition

Fellowship started: June 2017
Fellowship ending: June 2019

Sepideh got her BSc in chemistry and MSc in material science from Sharif University of Iran. Her initial career was as a technical manager in a metallurgical research centre. She gained her PhD in material science and engineering (corrosion and protection) from the University of Manchester, and followed this as a postdoctoral research associate on plasma electrolytic oxidation (PEO) on titanium.

The use of copper as a main accelerator cavity material is primarily due to lowering the cost of the cavity since high purity niobium costs around 40 times more than copper. Another important aspect is the copper thermal conductivity with respect to niobium that can be crucial in promptly transmitting the heat generated in local hot spots to the liquid helium bath. The aim of my work is a systematic study on the effect of substrate preparation to provide optimum interface quality to produce films which adhere strongly to reduce thermal contact resistance.

Important publications

  1. S. Aliasghari, M. Ghorbani, P. Skeldon, H. Karami, M. Movahedi, Effect of plasma electrolytic oxidation on joining of AA 5052 aluminium alloy to polypropylene using friction stir spot welding." Surface and Coatings Technology 313 (2017) 274–281.

  2. S. Aliasghari, P. Skeldon, and G. E. Thompson. "Plasma electrolytic oxidation of titanium in a phosphate/silicate electrolyte and tribological performance of the coatings." Applied Surface Science 316 (2014): 463-476.

  3. S. Aliasghari, A. Němcová, J. Čížek, A. Gholinia, P. Skeldon, and G. E. Thompson. "Effects of reagent purity on plasma electrolytic oxidation of titanium in an aluminate–phosphate electrolyte." Transactions of the IMF (2016).

  4. S. Aliasghari, S., T. Hashimoto, P. Skeldon, and G. E. Thompson. "Effect of Chloride Ions in Plasma Electrolytic Oxidation of Titanium." ECS Electrochemistry Letters 3. (2014): C17-C20.

  5. S. Aliasghari, A. Němcová, P. Skeldon, and G. E. Thompson. "Influence of coating morphology on adhesive bonding of titanium pre-treated by plasma electrolytic oxidation." Surface and Coatings Technology (2016).

Important talks

  1. S. Aliasghari, M. Ghorbani, P. Davami, N. Varahram, Characterization of Mixed metal oxide on titanium coated electrode based on RuO2-TiO2-IrO2, 13th Middle East corrosion conference & exhibition, 2010, Bahrain.

  2. S. Ahmadnia, S. Aliasghari, M. Ghorbani, Corrosion behavior of plasma electrolytic oxidation coatings in simulated body fluid (SBF) at silicate and calcium phosphate electrolytes, iMAT conference, Shiraz, Iran, 2016.
 

UK Astronomy Technology Centre

Carolyn Atkins

(Credit: Carolyn Atkins)

Additive manufacturing for the next generation of astronomical components

Fellowship started: August 2016
Fellowship ending: July 2018

My research investigates the application of additive manufacturing, commonly known as 3D printing, towards light-weight space-based optical components for astronomy. The advantage of additive manufacturing is that it allows the user to build an object layer-upon-layer in a wide range of materials, which means the designer is no longer constrained by traditional machining/tooling methods. Space-based imaging systems have to overcome the Earth’s gravity in order to achieve operation and therefore light-weight optical systems are paramount to ensure the maximum photon collecting area for a given launch-weight restriction. It is hoped during the two years of the fellowship that a series of proof-of-concept additively manufactured test samples will be created. These test samples will trial a variety of additive manufacturing materials and methods and study the effect of the light-weighting structures in terms of print-through upon the optical surface. The goal is to demonstrate that additive manufacturing can be used to create research grade optical components for space-based optical systems.

Important publications

  1. Carolyn Atkins, Charlotte Feldman, David Brooks, Stephen Watson, William Cochrane, Melanie Roulet, Peter Doel, Richard Willingale, Emmanuel Hugot, "Additive manufactured x-ray optics for astronomy," Proc. SPIE 10399, Optics for EUV, X-Ray, and Gamma-Ray Astronomy VIII, 103991G (2017/08/29);

  2. Charlotte Feldman, Carolyn Atkins, David Brooks, Stephen Watson, William Cochrane, Melanie Roulet, Richard Willingale, Peter Doel, "Design and modelling of an additive manufactured thin shell for X-ray astronomy," Proc. SPIE 10399, Optics for EUV, X-Ray, and Gamma-Ray Astronomy VIII, 103991H (2017/09/08);

Important talks

  1. Carolyn Atkins “Additive manufacturing of x-ray optics for astronomy” 103991G, oral presentation at SPIE Optics + Photonics, San Diego, USA, August 2017

  2. Carolyn Atkins “Additive manufacturing and high resolution X-ray optics”, Oral presentation at the International workshop on Astronomical X-Ray Optics (AXRO), December 2016
 

Diamond Light Source Ltd.

Ashley Hughes

(Credit: Ashley Hughes)

Development of time resolved pump-probe circular dichroism at B23

Fellowship started: April 2017
Fellowship ending: March 2019

Circular Dichroism (CD) is a technique whereby chiral molecules are probed by left and right circularly polarized light and the differences in absorption between the left and right polarized light are recorded. This provides information concerning the molecule and its environment and has been used for many years to probe the environment and structure of many biomolecules. In the far UV region (175-260 nm) it has been extensively utilised to probe protein secondary structure as a function of solvent, pH, temperature, pressure, detergents, and ligands whilst the near UV (250-350 nm) can be explored to investigate the structure of DNA and the ternary structure of proteins via the aromatic side chains. This fellowship will enable the development of a state-of-the-art time-resolved pump-probe facility at the B23 CD beamline at Diamond light source. A new range of experiments will be possible investigating, for example, photoactive proteins, caged ligand systems and temperature (T)-Jump experiments. These will be developed in a user friendly manner essential for reaching out to the broad UK Soft Matter and Biology communities.

Important publications

  1. Time-resolved X-ray solution scattering reveals the structural photoactivation of a light-oxygen-voltage photoreceptor

  2. Detection of interaction between protein trytophan residues and small or macromolecular ligands by synchrotron radiation magnetic circular dichroism

  3. Antithrombin stabilisation by sulfated carbohydrates correlates with anticoagulant activity

  4. Structural photoactivation of a full-length bacterial phytochrome

Important talks

  1. Development of Time-Resolved CD at Diamond Light Source (DLS, 2016)

  2. Development of 2DIR at Gothenburg University (Lundberg Retreat, 2016)

  3. Spectroscopic techniques to probe GAG-Protein Interactions. Their secondary structure, stability and furture developments (RSC/Biochemistry society, 2012)
 

UK Astronomy Technology Centre

Olivia Jones

(Credit: Olivia Jones)

Origins of Dust

Fellowship started: October 2017
Fellowship ending: September 2019

My astrophysics research focuses on infrared stellar populations in Local Group galaxies and what they have to say about the chemical evolution of the Universe.

Cool dusty stars and supernovae enrich the interstellar medium with heavy elements and dust grains. These dying stars emit radiation in the infrared. Therefore, using cameras on board the Spitzer Space Telescope, Herschel and the (soon to be launched) James Webb Space Telescope (JWST) the dust producing (and dust destroying) stellar populations of Local Group galaxies can be observed. This allows stars to be characterised on a galactic scale and constraints put on the chemical composition and, abundances of dust as a function of the metallicity (the ratio of heavy elements to helium), following the cosmic evolution of astrophysical dust from the high-redshift universe to the present-day.

To do this, the vast majority of my research involves analysing infrared spectroscopy, photometry and generating radiative transfer models.

Important publications

  1. The star-forming complex LMC-N79 as a future rival to 30 Doradus. Ochsendorf, B. B., Zinnecker, H., Nayak, O., Bally, J., Meixner, M., Jones, O. C., Indebetouw, R, Rahman, M, 2017, Nature Ast., 1, 268

  2. The SAGE-Spec Spitzer Legacy program: the life-cycle of dust and gas in the Large Magellanic Cloud. Point source classification - III. Jones, O. C., Woods, Paul M., Kemper, F., et al., 2017, MNRAS, 470, 3250

  3. Probing the Dusty Stellar Populations of the Local Volume Galaxies With JWST/MIRI. Jones, O. C., Meixner, M., Justtanont, K., Glasse, A., 2017, ApJ, 841, 15

  4. The mid-infared evolution of the FU Orionis disk. Green, J. D., Jones, O. C., Keller, L. D., et al., 2016, ApJ, 832, 4

  5. The Dustiest Post-Main Sequence Stars in the Magellanic Clouds. Jones, O. C., Meixner, M., Sargent, B. A., Boyer, M. L., Sewilo, M., Hony, S. & Roman-Duval, J., 2015, ApJ, 811, 145

Important talks

  1. What have we learnt / do not know about infrared populations? – Invited talk, MEGA-SAGEVIII, Keel

  2. SN 1987A: The Formation and Evolution of Dust in a Supernova Explosion – Invited talk, JWST Proposal Planning Workshop, STScI

  3. Near-IR stellar populations of Sextans A - The AGB-Supernovae Mass Transition, Rome

  4. The Stellar Populations of Local Volume Galaxies with JWST/MIRI - JWST Nearby Galaxies Workshop, California

  5. The life-cycle of dust in galaxies: Dust Production from Evolved Stars – Colloquium, Onsala Space Observatory, Sweden
 

UK Astronomy Technology Centre

Oscar Hernán Ramírez-Agudelo

(Credit: Marcelo Rubinho)

Properties of massive stars: single and binaries

Fellowship started: September 2016
Fellowship ending: September 2018

My research interests are focused on the study of the formation and evolution of massive stars (> 8 solar masses). Massive stars end their lives as core collapse supernovae. They are powerful cosmic engines that impact their surroundings affecting the evolution of the galaxies in which they reside. In recent years it has become evident that the majority of the most massive stars do not exist in isolation but form and evolve in binary systems. Massive binary systems can also be the progenitors of black hole binary systems and hence be potential gravitational wave sources such as GW150914, first gravitational wave source detected by LIGO.

The aim of my fellowship is to investigate properties of massive OB objects, single and binaries, located in different starburst regions in the Local Group. By analysing multi-epoch optical spectroscopy, obtained with different instruments of the Very Large Telescope, I determine stellar properties such as temperatures, luminosities, mass-loss rates, etc., for the single stars and orbital periods, mass-ratios, eccentricities, etc., for the binary systems. My work not only aims to constrain their stellar properties but also bridge the gap between observations and theoretical predictions. Finally, at UKATC I am also contributing to the Phase-A study of the potential second generation Multi-Object Spectrograph “MOSAIC” of the Extremely Large Telescope.

Important publications

  1. The VLT-FLAMES Tarantula Survey. XXIV. Stellar properties of the O-type giants and supergiants in 30 Doradus; Ramírez-Agudelo et al. 2017, Astronomy & Astrophysics 600, A81

  2. The VLT-FLAMES Tarantula Survey. XXV. Surface Nitrogen abundance of the O-type giants and supergiants; Grin, Ramírez-Agudelo et al. 2017, Astronomy & Astrophysics 600, A82

  3. Massive pre-main sequence stars in M17; Ramírez-Tannus (+Ramírez-Agudelo) et al. 2017, Astronomy & Astrophysics 604, A78

  4. The VLT-FLAMES Tarantula Survey. XXI. Stellar spin rates of O-type spectroscopic binaries; Ramírez-Agudelo et al. 2015, Astronomy & Astrophysics 580, A92

  5. The VLT-FLAMES Tarantula Survey. XII. Rotational velocities for the single O-type stars; Ramírez-Agudelo et al. 2013, Astronomy & Astrophysics 560, A29

Important talks

  1. Spectroscopic Surveys with the ELT: A gigantic Step into the Deep Universe, October 17-19, 2017, Toledo, Spain
    Talk: Pushing back the horizon: increasing the observations limit of massive stars

  2. Stars, Supernovae and Nucleosynthesis, September 4-5, 2017, Edinburgh, United Kingdom
    Talk: Stellar properties of O-type giants and supergiants in 30 Dor

  3. Instituto de Astronomia, Geofisica e Ciencias Atmosféricas (IAG), September 17-19, 2016, São Paulo, Brasil
    Colloquium talk: Rotation in massive stars in the Tarantula Nebula

  4. Magnetism and variability in O stars, September 17-19, 2014, Amsterdam, The Netherlands
    Talk: Observed rotational properties of the O-type stars in the Tarantula Nebula: single and binaries

  5. International Astronomical Union Symposium #307: New Windows on Massive Stars, Asteroseismology Interferometry and Spectropolarimetry, June 23-27, 2014, Geneva, Switzerland
    Talk: Observed rotational properties of the O-type stars in the Tarantula Nebula: single and binaries

Science and Technology Facilities Council Switchboard: 01793 442000