PhD Projects in The School of Physics
Supervisor name & contact details:
Dr. Harald Berresheim
email: harald.berresheim@nuigalway.ie
Characterizing Strong Oxidants in the Atmosphere: The Self-Cleaning Power of the Atmosphere
and its Limitations
Project Description: The atmosphere has two major possibilities to clean itself: (1) by rainout of water soluble
particles and gases, and (2) by oxidation reactions resulting in products with higher water solubility which can
then be removed by rain. The most important oxidant in the lower atmosphere is the OH radical which is
produced during daytime from sunlight in the presence of ozone and water vapour. My research group has
achieved - for the first time worldwide - long-term measurements of OH concentrations in the coastal
atmosphere which started in 2009 at our Mace Head research station near Carna, Connemara. We are using a
highly sophisticated mass spectrometry method based on chemical ionisation of target molecules in
conjunction with a broad range of supporting trace gas and aerosol measurement techniques. Our research
contributes to better understand the changing composition of the atmosphere as a result of man-made
pollution and global climate change. We have detected at least one unidentified oxidant species of similar
importance to OH which may result from iodine emissions by seaweed indicating the potential importance of
marine biology to the self-cleaning of the atmosphere. Currently, we are planning to extend our measurement
programme in a major collaboration with the University of Bristol (UK) and the Research Center Jülich
(Germany).
Identification and Treatment Options for Waste Streams of Certain Bromine Containing Flame Retardants
(WAFER)
Project Description: The Environmental Protection Agency (EPA) has recently announced a research
programme to establish a national survey of the presence of persistent organic pollutants (POPs) in electronic,
vehicular, and construction waste in Ireland. Of particular importance are bromine containing substances
which have been added to corresponding materials as flame retardants and which may constitute a significant
health risk if leached into water systems by rain or other processes. In collaboration with the University of
Bristol we have submitted a proposal to the EPA which is currently under review. We anticipate that it will be
funded and research will begin in spring 2015. There will be a need for one PhD student to be engaged in field
measurements at corresponding sites in Ireland and contributing to the data analysis and a final synthesis
report to the EPA. The student will be trained and partially supervised by a postdoctoral fellow who has
already strong expertise in this research area. We expect from the student a strong interest for environmental
themes, practical engagement with measurement techniques, and basic knowledge of pollutant chemistry (a
physics student can do this !).
Co-supervision with Prof. Stuart Harrad (Univ. Birmingham, UK)
Supervisor name & contact details:
Dr. Ray Butler
email: ray.butler@nuigalway.ie
Optical variability in Ultra-cool Dwarf Stars
Project Description A number of ultra-cool dwarfs (the dimmest red dwarf stars and brown dwarfs, which are
essentially “failed” stars) have been unexpectedly detected as radio sources in the last decade. Four of them
produce strong periodic radio pulses. Our collaboration has now shown that several of these pulsing dwarfs
are also periodically variable in optical photometry, and that the detected optical periods match the periods of
the radio pulses, which have been associated with the short rotation periods of the dwarfs. Our development
and extended usage of the GUFI (Galway Ultra Fast Imager) photometric camera on the 1.8m VATT telescope
(Mt. Graham, Arizona) was the largest enabling factor in this breakthrough. For one dwarf, it was established
that the optical and radio periodic variability are probably a consequence of magnetically-driven auroral
processes. However, other causes (magnetic cool star-spots and atmospheric dust clouds) must also be
considered. The student will conduct observing campaigns with GUFI , and analyse the photometric timeseries data (and re-analyse existing GUFI data) using newer "Optimum Aperture" & "Lucky Phot" techniques,
in order to investigate the ubiquity, the stability (in both period and amplitude), and the cause(s) of the
periodic optical variability in radio detected dwarfs.
Development of a GIS system for optimally siting a small observatory.
Project Description: At present, the School of Physics/Centre for Astronomy operates the Imbusch
Observatory on campus. This is a convenient location for undergrads and the public to get to – its main
purposes are teaching and public outreach – but it is badly affected by urban light pollution. A dark-sky
location somewhere in Connemara would be preferable for a second NUIG astronomical observatory. But
choosing the best site is complex, with many constraints and metrics to consider – not just light pollution, but
also financial, logistical, legal/planning, access, travel-time, a preference for altitude and an open aspect – and
some of these constraints are actually in competition with each other. Obtaining accurate metrics data for our
region (sky darkness etc.) will be a key component of this project. In parallel, the project will develop a tool to
assign variable weights to these factors, combine, and colour-code the data by GIS (Geographical Information
Systems) techniques as "heat" gradients on a map. Thus, the impact of different factors can be easily explored
- the map will instantly regenerate from new weightings. The tool produced will be useful globally – users will
simply assign their own locally-determined data, choose their weightings and generate maps for their own
region.
Variable Stars in Globular Cluster Centres
Project Description: Globular star clusters are unique “labs in the sky”. The rich ecology of populations that
we have studied in them includes several classes of variable stars (RR Lyrae, Type II Cepheids, Blue Stragglers),
close binary stars, millisecond pulsars, and even an extra-solar planet. In pursuing these objects, we have
developed parallel-processing deconvolution software, and shown that performing deconvolution of Hubble
Space Telescope (HST) images yields more accurate detection and measurement (astrometry) of the stars in
the crowded centres of the clusters, revealing milli-arcsecond motions of the stars over time. Meanwhile,
precise image-matching methods have enabled us to photometrically discover and characterize new variable
stars in globulars . This project will extend these methods to new targets, mining the HST archive to conduct a
variability census in the most difficult and crowded cluster centres - where many new variable
announcements have never been independently verified, and identifications/classifications have sometimes
been ambiguous, so there is a need for a consistent, precise treatment on "known" variables - in addition to
the scope for further new discoveries. Specific science goals include long-timebase monitoring for secular
changes. Analysis will also be performed on simulated cluster images, to benchmark the techniques.
Scientific characterization of commercial camera sensor performance
Project Description: The success of websites like DxOmark.com and DPreview.com shows that there is clearly
a huge demand in the imaging/photography markets for independently produced sensor performance data.
However, these sites tend to focus on relatively qualitative comparisons and unscientific test subjects, and
they entirely neglect some key performance factors like long exposure dark noise, manipulation of bit depth,
and the noise-skewing effects of internal bias subtraction in many camera models. This project will integrate
methods for more rigorous characterization, through photon-transfer curves etc. Where data is zero-clipped
(due to internal bias subtraction), new statistical methods will be developed for recovery of the noise
measures. Working through the new industrial liaison officer for the College of Science, mutually beneficial
partnerships will be forged with local suppliers for access to test/demo units, in return for good publicity and
the kudos of academic-civic cooperation, which is a strategic goal of the university. Development of a mobile
test rig would be the most effective way to quickly collect project data at supplier premises.
Supervisor name & contact details:
Dr. Miriam Byrne
email: miriam.byrne@nuigalway.ie
Parameter refinement and utilisation of a multi-zone multisource probabilistic indoor air quality
model for accurate assessment of exposure to particulate air pollution
Project Description Airborne Particulate Matter (PM) is internationally-acknowledged as a major
environmental concern because of its known adverse impacts on human health, and since we spend
approximately 89% of our time indoors, indoor PM deserves particular attention. The use of computational
models in predicting indoor PM exposure, for individuals and population groups, has been well documented,
but the accuracy of such predictions is limited by model input uncertainties, particularly with respect to
building ventilation rates and combustion source emission rates. In this project, the latest probabilistic
modelling technology will be refined, by providing accurate input data (currently non-existent), generated
through experiment, on ventilation and combustion source emission rates. The refined model will then be
used to provide, for the first time, accurate PM exposure estimates for occupants of a broad range of buildings
who are subject to multiple PM sources. These results will benefit numerous stakeholders, e.g. policy makers,
who wish to investigate whether reducing building ventilation rates (for reasons of energy conservation) will
result in elevated PM concentrations indoors. In addition, the degree of protection afforded, for example, by
staying inside a building during an atmospheric release of PM that is of a biological or radioactive nature can
also be accurately assessed for the first time using this model.
Supervisor name & contact details:
Dr. Marie Coggins
email: marie.coggins@nuigalway.ie
Evaluating the health benefits of energy efficient retrofits in the residential sector
Project Description: In recent years there has been much emphasis on improving the energy performance of
European buildings, this sector accounts for 40% of the total EU energy usage and is the main focus of the
Energy Performance Buildings Directive (EPBD, 2002/91/EC; 2010/31/EU).
Energy efficient measures have some obvious direct health benefits such as increasing indoor temperatures
and occupant comfort , however it is not clear how increased building air tightness will impact on levels of
indoor air pollutants, such as particulate matter. In most developed countries the population is known to
spend upward of 80% of their time within indoor environments as a result exposure indoors likely to play a
significant role in human health.
The impacts of increasing the energy efficiency of buildings are largely positive; along with reducing energy
use, helping to meet National and EU Energy targets, the building retrofit should improve indoor temperature,
and reduce moisture, which in turn may improve mental and respiratory health of residents. However there
are some concerns that increasing building air tightness may have a negative effect on indoor air quality (IAQ),
which in turn could affect health. Drawing on the results from another EPA sponsored project on IAQ in
energy efficient homes, this project proposes to evaluate the health benefits of energy efficient retrofits.
Supervisor name & contact details:
Dr. Ger O Connor
email: gerard.oconnor@nuigalway.ie
Short pulse laser material interactions for large area electronics / medical devices
Project Description: Understanding laser-matter-ambient-interactions is important to realise the potential of
high repetition rate, multi-kiloWatt, femtosecond and picosecond laser technologies in scalable production.
The fabrication of integrated multifunctional thin film devices by additive (inkjet, spray) and subtractive (laser)
manufacturing on Roll to Roll (R2R) production platforms is also suddenly possible and desperately needed to
realise new cost effective manufacturing solutions.
Enquiries from potential PhD students are sought to develop new understanding of short pulse laser matter
interactions relevant to very thin films and R2R manufacturing platforms. A particular focus will be the
development of on-line tools which will create new process monitoring tools for cost effective production
based on new nano-inspired materials relevant to flexible large area electronics and medical devices.
Supervisor name & contact details:
Dr. Nicholas Devaney
email: nicholas.devaney@nuigalway.ie
Camera arrays for novel applications
Project Description: Moblie phone cameras have developed dramatically in the last few years. Nevertheless,
the push towards thinner phones places severe limits on the image quality that can be obtained. A possible
solution is to use multiple cameras together with advanced image processing on the phone’s microprocessor.
There are many different ways to approach this; for example, different cameras could have different aperture
sizes or be sensitive to different wavelengths or even different polarisations. They could be sequenced
temporally and have different exposoure times in order to improve the capture of synamic scenes.
Applications include 3D/depth information, object recognition through shape, time-signature,wavelength and
polarisation, enhancement of resolution, colour fidelity and dynamic range. The project will commence with
computer modelling and proceed to developing prototype systems.
Extraction of exoplanet spectal signals
Project Description: Imaging and spectroscopy of planetary systems around other stars is one of the most
exciting challenges in current astronomy. Dedicated instruments have recently been built for the largest
telescopes in the world and are now being commissioned. There is a need for algorithms to extract the
information from these instruments in an optimal way, and we have developed a novel approach which we
call ‘PEX’ (Plane Extractor). The initial application is to the reconstruction of images of the extrasolar planetary
systems. It is also of great interest to apply this approach to extracting spectral information. This has the
potential to provide direct spectra of the extrasolar planets, which would allow us to determine physical
properties such as atmospheric composition. The holy grail of exoplanet studies is to detect ‘biomarkers’ i.e.
the spectral signature of life.
A comparison of novel wavefront sensing techniques
Project Description: Wavefront sensors are used to measure aberrations in optical systems. The
measurements can be used to determine the quality of an optical system. Alternatively, the measurements
can be used to control wavefront correction in an adaptive optics system. Wavefront sensors usually involve
special hardware and a dedicated detector. However, it is also possible to estimate wavefront errors from a
pair of images, one of which has a known defocus. This is referred to as ‘phase diversity’ and it is of
considerable interest given the simplicity of the hardware involved. The aim of this project is to carry out a
direct comparison of wavefront measurements obtained using a ‘standard’ wavefront sensor and phase
diversity. The conditions under which phase diversity can compete in performance will be determined
experimentally. This project will be of interest for future adaptive optics systems and for systems aiming to
correct aberrations in space telescopes.
Adaptive optics for free-space optical communication.
Project Description: Free-space optical communication uses a laser beam to transmit information through the
atmosphere. This can have a very high bandwidth, and has been proposed for communication between points
on the ground and between the ground and space satellites. However, when a laser beam propagates
through the turbulent atmosphere, the result is variations in the beam amplitude and phase which causes
random fluctuations in the intensity. The aim of adaptive optics (AO) is to measure and correct these phase
errors in real time. All major astronomical telescopes now employ adaptive optics to provide diffraction-
limited imaging, at least in the near infrared. Application to laser beam correction is complicated by the severe
turbulence encountered on horizontal paths, while the correction of beams to satellites requires very high
speed correction. In this project we will investigate techniques to characterise turbulence over horizontal
paths (e.g. across the Corrib river). Based on these measurements, an adaptive optics system will be
developed and tested. In particular, a novel wavefront sensors based on ‘point diffraction interferometry’ will
be investigated. This sensor is expected to be very efficient, and to be robust to conditions of strong
turbulence.
Characterising atmospheric turbulence
Project Description: The characterization of atmospheric turbulence is vital for imaging and optical
communication through the atmosphere. Current techniques to measure the strength of turbulence rely on
observing stars or the sun and are therefore restricted in use. Our collaborators in this project, Georgia Tech
Research Institute(GTRI), have recently demonstrated a lidar based turbulence profiler which provides the
opportunity to measure turbulence at any time and along arbitrary paths. There is now an opportunity to
exploit this instrument in order to make detailed studies of atmospheric turbulence at different sites. In this
project, new algorithms will be developed to process and analyse data from the lidar profiler. In particular, a
robust reconstruction of the turbulence profile in altitude will be demonstrated. A temporal analysis will be
developed in order to estimate wind speed profiles. Intensity fluctuations in the data will also be analysed and
we will investigate the use of this information in the turbulence profile estimation. This device will potentially
be deployed at ground stations for satellite-to-ground laser communication, astronomical observatories and
other sites where knowledge of atmospheric turbulence is important, such as airports.
High-resolution Retinal Imaging for the early detection of disease
Project Description: Classical ophthalmological instruments have poor resolution and cannot detect the early
stages of retinal diseases. The result is that these diseases are not detected until the symptoms become
obvious, and then it may be too late for clinical intervention. Adaptive Optics has proven its ability to provide
images with resolution at the cellular level, but we lack robust, automatic tools to analyse these images. AO
images of the retina may contain a huge amount of information, and it becomes imperative to assist the
clinician with automated tools to quantify the information, monitor changes in structures between visits to
the clinic and to call attention to signs of disease. This work will build on an international collaboration
between ophthalmologists and adaptive optics/image processing specialists in order to develop these tools.
They will be tested on images from a large sample of both healthy and diseased eyes. It is expected that the
results of this work will have a major impact on the clinical ophthalmology community.
Supervisor name & contact details:
Professor Colin O’Dowd, MRIA, DSc
email: colin.odowd@nuigalway.ie
Aerosol-Cloud Interactions in Marine and Continental Air
Project Description: NUIG/CCAPS, at Mace Head, possess the most fruitful database of continuous
measurements of aerosol physics, chemistry, hygroscopicity, scattering and activation into cloud condensation
nuclei. In addition, there exists a temporally-parallel data base of cloud properties which is to be combined
with the aerosol properties to develop an aerosol-cloud-interaction parameterisation.
Key Words: remote sensing; cloud microphysics; aerosol; RADAR; LIDAR.
Ground Based Remote Sensing of Cloud Microphysics
Project Description: NUIG/CCAPS, at Mace Head, deploy a CLOUDNET suite of ground-based meteorological,
aerosol and cloud remote sensors (microwave humidity/temperature, aerosol LIDAR, and cloud RADAR
profilers) and, combining these sensors in a synergetic manner, have been at the forefront of development of
cloud microphysical parameters relevant to aerosol-cloud-climate interactions. This PhD involves further
development of the retrievals to multiple clouds types and will contribute to reducing the uncertainty in
aerosol-cloud-climate interactions.
Key Words: remote sensing; cloud microphysics; RADAR; LIDAR.
Air Quality-Cloud-Climate Interactions
Project Description: Air pollution has a direct impact on climate by producing regional haze layers and clouds
which scatter and reflect incoming solar radiation. Global diming observed worldwide since the middle of last
century turning into global brightening exacerbating global warming. A combined analysis of the air quality
trends with those of global radiation across EMEP and IMPROVE networks will highlight future climate
changes due to aerosol effects.
Key Words: Air quality, global radiation, cloud, climate forcing.
Evolution of primary organic matter – from source to sink
Project Description: Primary marine organic matter is a unique atmospheric constituent affecting aerosol
physico-chemical properties, cloud condensation nuclei and cloud formation in marine atmosphere. Tightly
related to biological activity at the ocean surface, primary organic matter in sea spray undergo chemical
evolution in the atmosphere affecting its volatility, hygroscopicity and oxidation state. NUIG/CCAPS, at Mace
Head, developed a simulated system to study transformation and evolution of primary marine organic matter
produced at the lowest trophic level.
Key Words: remote sensing; cloud microphysics; aerosol; RADAR; LIDAR.
North Atlantic Regional Air Quality in Marine and Continental Air
Project Description: North-East Atlantic region is a unique natural laboratory for exploring air quality on a
regional as well as hemispheric scale. NUIG/CCAPS, at Mace Head, possess the most fruitful database of
continuous measurements of air quality. Langrangian approach to air pollution network data and the use of
isotopic methods offer unparalleled tools for establishing sources and sinks of particulate air pollution and the
trans-boundary pollution budget.
Key Words: Regional Air Quality, trans-boundary air pollution.
Parameterization of Indirect Aerosol Effect.
Project Description: This project would aim at parameterising the CCN activation efficiency as a function of
particle hygroscopicity, composition and size, deploying the long term concurrent measurements of aerosol
chemical and physical properties, such as size segregated chemical composition, particle size distribution,
hygroscopisity and particle activation to cloud condensation nucleus (CCN). Existing data sets would be used
along with the new measurements.
Key Words: Aerosol Mass Spectrometry; CCN activation; aerosol hygroscopic growth.
The role of Primary Marine Organics on Climate Effects.
Project Description: Long term high time resolution aerosol chemical composition measurements at Mace
Head capacitate a development of an advanced primary marine organic – chlorophyll parameterization for
deployment in the sea spray source function, used for the climate modelling. The project would aim at
identifying and quantifying the primary marine organics by combining the ambient marine aerosol
measurements obtained by Aerosol Mass Spectrometry (AMS) and source apportionment techniques with
laboratory experiments, which then would be used for the development of the parameterization.
Key Words: Aerosol Mass Spectrometry; marine organics; sea spray aerosol.
Ground Based Remote Sensing of Cloud Microphysics
Project Description: NUIG/CCAPS, at Mace Head, deploy a CLOUDNET suite of ground-based meteorological,
aerosol and cloud remote sensors (microwave humidity/temperature, aerosol LIDAR, and cloud RADAR
profilers) and, combining these sensors in a synergetic manner, have been at the forefront of development of
cloud microphysical parameters relevant to aerosol-cloud-climate interactions. This PhD involves further
development of the retrievals to multiple clouds types and will contribute to reducing the uncertainty in
aerosol-cloud-climate interactions.
Key Words: remote sensing; cloud microphysics; RADAR; LIDAR.
Characterising trans-boundary air pollution
Project Description: NUIG/CCAPS will deploy the state of the art Weather Research and Forecasting model
with coupled Chemistry (WRF-Chem) in conjunction with extensive in-situ measurements from its Global
Atmosphere Watch monitoring station to quantify the effect of trans-boundary air pollution for a range of key
air quality indicators at both a national and regional level and how this may change under future emission
scenarios.
Key Words: air quality, modelling, trans-boundary, climate change
Quantification of the atmospheric effects of SO2 and ash emissions from volcanic eruptions
Project Description: NUIG/CCAPS will deploy the state of the art Weather Research and Forecasting model
with coupled Chemistry (WRF-Chem) for modelling of the emission, transport, dispersion, aggregation,
chemical processing and loss mechanisms of SO2 and ash from volcanic eruptions. The model will be validated
with satellite retrieval data and ground based in-situ measurements and operational forecast capabilities will
be developed.
Key Words: Volcano, SO2, modelling, ash emissions
Supervisor name & contact details:
Dr. Mark Foley
Email: mark.foley@nuigalway.ie
Intramodality 3D ultrasound imaging for image guided radiation therapy (IGRT)
Project Description: Modern radiation therapy techniques allow for greater conformity of the radiation dose
to the planning target volume (PTV), thus sparing surrounding healthy tissue. Consequently steeper dose
gradients have been employed to improve clinical outcome, however to avoid an increased risk to healthy
tissue, this has been coupled with a decrease in the PTV margin. This decrease in the PTV margin makes the
delivery of radiation therapy more sensitive to geometrical uncertainties, such as patient set-up relative to the
coordinate system of the treatment room, and internal organ motion. Image guided radiation therapy (IGRT)
is employed to allow precise daily localization of the target, thus minimizing the effect of inter-fraction
motion. The goal of this project is to focus on the challenges presented when implementing intramodality 3D
ultrasound imaging for IGRT.
Pre-clinical imaging in biomedical research
Project Description: Pre-clinical imaging technology has developed considerably in recent years. Molecular
imaging techniques such as Ultrasound, MRI, SPECT, PET and CT are used routinely in Biomedical research labs
around the world. In-vivo imaging can now be considered as an essential component of translational research
studies aimed at improving our understanding of the mechanisms of disease and developing therapeutic
strategies. Pre-clinical imaging provides the capability to carry out longitudinal studies on same group of
animals over time, where previously animal sacrifice and dissection would have been necessary at each time
point. This project will focus on the application and optimisation of molecular imaging technology available in
state-of-the-art preclinical research facilities.
Supervisor name & contact details:
Dr. Gary Gillanders and Dr. Mark Lang
email: gary.gillanders@nuigalway.ie
mark.lang@nuigalway.ie
High Energy Astrophysics using the VERITAS Telescope Array
Project Description: Over a hundred astrophysical sources of Very-High-Energy gamma radiation (VHE,
E>100GeV) are currently known, including nearby supernova remnants, and distant active galactic nuclei. Our
research involves using the VERITAS telescope array (see veritas.sao.arizona.edu) to study these objects to
help uncover how they produce radiation with such incredible energies. VHE gamma-rays observations can
also be used to make more general measurements of the extragalactic background light, Lorentz invariance,
and to search for dark matter.
VHE gamma-rays produce cascades of relativistic electrons in the atmosphere and VERITAS can detect the very
brief flashes (nanosecond) of optical Cherenkov light emitted by these cascades. Sophisticated multi-view
image analysis techniques are used to reject a large background of charged cosmic ray initiated cascades.
Sample MSc project: Observations of VHE gamma-ray emission from a nearby radio galaxy. This project
involves the analysis of a large existing data base.
Sample PhD project: Familiarisation with the VERITAS data analysis procedure; observations at the VERITAS
site; participation in a major VERITAS science project such as constraining the extragalactic background light
using VHE observations of AGN.
Supervisor name & contact details:
Dr. Alexander Goncharov
email: alexander.goncharov@nuigalway.ie
Optical modeling of the Human Eye
Project Description: The current problems of an earlier onset of myopia (short-sightedness) in young eyes is
probably related with excessive use of gadgets for reading, writing and playing, which requires that the eye is
kept in the accommodated state (crystalline lens gains more optical power by assuming more convex shape)
as a result of this and probably other factors the eye globe undergoes more growth in length than usual. The
mismatch of the length of the eye and the optical power of the cornea and the lens leads to myopia, the
image formed at the retina is out of focus. One possible explanation for the development of myopia is the
signal at the periphery of the visual field (off-axis blur). To study the impact of accommodation on the off-axis
blur one needs an accurate model of the crystalline lens, which is in the accommodated state. The optical
modelling of the image formation through the accommodated crystalline lens featuring gradient index of
refraction and the effect of eye growth on image sharpness is the main topic of this study. The project will
commence with computer modelling of the optical system of the eye with an adjustable crystalline lens
representing biometrically sound process of accommodation.
Wide field imaging in the mobile phone cameras with optical zoom
Project Description: Every eye a new generation of mobile phone cameras appear on the market, bringing
more pixels, sharper images and better low light performance. The missing feature is the optical zoom in the
camera lenses, which is obviously not easy to fit into a thin 6-5 mm mobile phone housing. There are possible
solutions to locate the zoom lens along the side of the phone gaining sufficient space to perform zoom
function, however the solutions are not trivial and require some novel concept to achieve at least 2-3 time
zoom, which does not compromise on imaging quality. In addition one would like to attain a wide 60-70 deg
field at the short end of the zoom range, this puts extra complexity in the lens design featuring mainly plastic
lenses. The initial phase of the project is to show which concept can meet the current requirements in mobile
phones. Using optical ray tracing program one could model different scenarios who to design a compact zoom
and proceed with the best design to manufacture a prototype system. This project will be in collaboration
with the research and development company, FotoNation company, which is based in Galway.
Custom designs for intra-ocular lenses
Project Description: A typical cataract surgery requires replacement of a partially opaque crystalline lens by a
transparent ocular implant. This dramatically reduces internal light scattering and provides unobstructed
image formation on the retina. If the optical power of the IOL is chosen correctly, it can compensate for nearor long-sightedness by removing the major refractive error (defocus) of the cornea. IOL power calculations for
patients undergoing cataract surgery are usually based on the measurement of the optical power of the
cornea and the axial length of the eye. Over the years, dozens of formulae have been proposed for IOL power
calculation, in all of them the anterior and posterior corneal surfaces are combined to one surface, and the IOL
is approximated by a thin lens. To resolve this problem, one could apply an exact ray-tracing method instead
of regression formulae. Individual rays are traced through all refractive surfaces in the eye. The ray-tracing
guided prediction of the lens position and IOL customization utilizes a personalized eye model describing all
patient-specific parameters, such as corneal topography, the crystalline lens shape, inter-ocular distances and
refractive indices. The main advantage of the ray-tracing approach is that one can take into account peculiar
features of the patient’s eye including optical irregularities of the cornea. It might be feasible to measure
these individual features using current ophthalmic instruments.
Supervisor name & contact details:
Dr. Matt Redman
email: matt.redman@nuigalway.ie
Star and planet formation in the ALMA era
Project Description: The Atacama Large Millimetre Array (ALMA) in the Chilean desert has now begun
operations. This is perhaps the largest ground based international scientific project of the decade. ALMA will
revolutionise our ability to observe star and planet formation. High resolution molecular line data will reveal
the innermost regions of star forming clouds for the first time.
The principal aim of this research programme is to use our unique molecular line radiative transfer code
(MOLecular LIne Explorer - MOLLIE) to characterise, model and reproduce ALMA molecular spectral line data
from a wide variety of astrophysical sources, in particular star and planet forming molecular clouds and disks.
MOLLIE will be used to model the rich and complex data that ALMA will produce. This will allow us to
determine the physical conditions deep in these clouds and further our understanding of the star and planet
formation process.
Modeling the onset of massive star formation
Project Description: The most massive stars are rare in number but disproportionately influential in the
evolution of galaxies. Their winds, ultraviolet radiation fields and rapid evolution to supernovae greatly disturb
the local environment, out of which thousands of low mass, sun-like stars will also be forming. These effects
are mixed in that the sweep of shock waves on nearby molecular gas can trigger a new burst of star formation
but can also disrupt individual star forming clouds or their protoplanetary disks.
This project will investigate the process by which newly formed massive stars disrupt the thousands of low
mass stars forming alongside them. The competing processes of ionization-led erosion and external pressure
crushing on protostars will be modeled to estimate the amount of gas that will form a star and protoplanetary
disk. The response of protostellar objects to the passage of a supernova blast wave will also be modelled.
Depending on their evolutionary state, the shock could accelerate their collapse, disrupt their outer layers or
even disperse them completely.
At all stages, the models will be compared directly with observations, particularly from the new immense,
globally funded, Atacama Large Millimetre Array (ALMA) that will examine the internal structure of star
forming regions in unprecedented detail.
Viewing the universe with hydrogen cyanide
Project Description: The principal aim of this research programme is to comprehensively understand the
peculiar emission properties of the HCN molecular spectrum, particularly when observed towards star forming
clouds. The research will be to characterise, model and reproduce the HCN spectrum so as to allow this
astronomical tracer species to be used to its full potential. The proposal is very timely since the first
observations from the 1 billion dollar Atacama Large Millimetre Array (ALMA) in the Chilean desert are now
well underway. This is perhaps the largest ground based international scientific project of the next decade and
will revolutionise our ability to observe the star and planet formation process. HCN will be one of the key
tracer species that will routinely used as an observational tool. This project will fully open up the HCN window
on the universe allowing observations to be fully and correctly interpreted for the first time.
Supervisor name & contact details:
Professor Andy Shearer
email: andy.shearer@nuigalway.ie
Determining the emission mechanism of rotation powered pulsars.
Project Description: Pulsars, rapidly rotating neutron stars, were first detected nearly fifty years ago. Since
then, despite a wealth of observational material we still have no comprehensive picture for how they work.
Understanding pulsar emission is important as it has both physics and astrophysics. For physics pulsars are
environments for extremes – the highest known magnetic fields, strong gravity (and thus providing important
tests of general relativity), very high energy plasmas. For astrophysics pulsars represent the end of a stars life
and will help us understand the number of neutron stars and hence rate of type two supernovae. The Galway
group has interests in a number of different areas of pulsar astrophysics all of which are suitable for a PhD
project.
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4.
Optical observations of pulsars and pulsar systems using a combination of instruments ranging from
our own GASP, the Padua group’s Iqueye instrument, BVIT on the South African Large telescope.
These observations – primarily looking at the polarisation of the light from the pulsar - will be
complemented by Hubble Space telescope and other observatory instruments to understand both
the emission mechanism and the location of this emission within the pulsar’s magnetosphere.
Gamma ray observations of pulsars using the Fermi and Integral satellites. In particular we want to
extend our work on gamma ray polarisation studies.
Continued development of our theoretical/computational programme looking at the development of
particle-in-cell simulations of a pulsar’s plasma and/or the reverse engineering code to map the
pulsars magnetosphere using polarisation observations.
Development of the GASP polarimeter – this will involve mainly optical design and construction of a
new variant of the GASP polarimeter in particular to determine the absolute limitations of the 2-D
division of amplitude polarimetry method.
All of these projects will involve collaborations with groups in France, Germany, Italy and Poland. Projects (13) would be more straightforward for Physics with Astrophysics students although any good physics student
could develop the necessary skills. Project for is suitable for Applied Physics and Physics with Astrophysics
students.
Supervisor name & contact details:
Dr. Brian Ward
email: bward@nuigalway.ie
The impact of waves and oil on upper ocean turbulence
Project Description: Investigation of physical processes responsible for the spreading of oil products in ice free
and ice covered waters will help to develop technology for the remediation of Arctic environment and
reduction of environmental risks in the Arctic associated with oil contamination.
Surface waves propagating from clean waters into areas covered by a flexible surface cover, e.g. an oil slick or
sea ice, will become (a) heavily damped due to frictional forces. The air-sea momentum fluxes that force the
oceanic mean flows (b) depend on the waves and hence these will also be affected by the surface cover. In the
wave damping process the waves exert a stress on the surface cover, hence (c) inducing mean flows that bring
about changes in the surface cover properties, which will in turn impact on (a) the wave damping. Very few
studies have considered the full coupling between the waves, the momentum fluxes, and the mean flow, and
experimental evidence to validate components of such theories is lacking. The primary aims of the proposed
project are to determine:
-how different surface covers will damp waves,
-how these surface covers impact on the air-sea fluxes,
-how much of the lost wave momentum will lead to increased mean flow,
-how the near surface turbulence and effective viscosity are affected by the covers.
Role of air-sea heat exchange on sea ice
Project Description: Present area, thickness and mobility of the Arctic ice cover is a manifestation of climate
change with huge implications for ocean circulation, global weather, economics and governance. The seasonal
sea ice cycle drives large variations in the transport of heat, buoyancy,
and the compounds that fuel the biogeochemical cycles. The role of ocean, either directly or through feedback
mechanisms, is under debate.
Estimates of oceanic heat fluxes are dwarfed by large uncertainties, mainly due to lack of observations of
sufficient quality. It is, however, beyond doubt that the circulation patterns of the Atlantic Water layer in the
Arctic Ocean and the presence of a cold halocline layer “protecting” the ice cover are sensitive to diapycnal
mixing rates in the ocean. Identifying principal mechanisms for ocean heat transport processes and
quantifying their contribution are crucial for the Arctic heat budget as well as global scale weather and
climate. NICE will contribute in better constraining climate models and reducing the errorbars on ocean heat
fluxes. It is not the aim of NICE to produce new parameterizations for climate models – a task for a larger coordinated project – however, the knowledge gained and data collected will pave the way for observationbased parameterizations.
Study of the Freshening Effect of Rainfall On Sea Surface Salinity
Project Description: One of the most important issues facing society is how the future water cycle may be
affected by a changing climate. The exponential increase in the vapour-carrying capacity of the atmosphere
with temperature implies that changes could be severe. The distribution of rainfall, and associated floods and
droughts, is arguably the single most societally-relevant aspect of climate change. Since the vast majority of
the water cycle takes place over the oceans, it is clear that changes in water cycle over the ocean must be
monitored. There are clearly significant technical challenges associated with measuring precipitation over the
ocean. However, the recent launch of satellites capable of sensing sea surface salinity (SSS), such as ESA’s Soil
Moisture Ocean Salinity (SMOS) mission, offer a potential way forward. Since SSS is largely determined by the
local balance between evaporation and precipitation, it is anticipated that changes in SSS, as measured by
SMOS, may be used as a proxy for changes in the water cycle over the ocean. A potential problem for this
methodology is related to the fact that SMOS only samples the upper centimetre of the water column. In
areas where strong near-surface salinity gradients exist, changes in the upper centimetre may not be
representative of those in the upper several metres of the ocean. There remains a pressing need to investigate
the magnitudes of these gradients, under different mixing regimes. The field component of the proposed
project is strongly associated with the Salinity Processes in the Upper-ocean Regional Study 2 (SPURS2)
program. This investigation will take place in the eastern equatorial Pacific Ocean in late 2015. The low
salinities in this region are driven by some of the largest rainfall rates on the planet. This high rainfall plays a
key role in determining the upper-ocean stratification, in particular by forming small freshwater “puddles”
which can cover the upper several metres of the water column and suppress vertical mixing. The overarching
goal of this project is two-fold. Firstly, we will seek to understand and quantify how strong salinity gradients
are. Secondly, we will directly compare SMOS estimates of SSS with in-situ measurements. Microstructure
profilers are a common method of measuring salinity structure in the upper ocean. Unfortunately, almost all
of these operate in a downward profiling mode. A consequence of this is that they are not able to observe the
crucial upper 5-10 metres, which is required in order to validate SMOS measurements. In order to capture this
region, an upwardly rising profiler must instead be used. The Air-Sea Interaction Profiler (ASIP) is one such
profiler. ASIP is extremely well-suited to observing the upper ocean, particularly in its almost unique ability to
sample the upper several metres of the water column in high-resolution. This will allow us to understand the
salinity structure in this under-sampled region, and allow for a proper validation of SMOS. It is anticipated that
this comparison will allow for potential biases in SMOS to be identified, and permit corrections to be
ultimately developed.