Undergraduate Research Programme

The Astrophysics/Physics undergraduate research programme offers undergraduate students an invaluable opportunity to take part in cutting-edge research being undertaken by staff members in the Centre for Astrophysics Research (CAR), which is a leading Astrophysics department in the UK. These projects are designed to give undergraduate students a taste of what working in frontier research is like and often contribute to journal publications. We welcome interest both from undergraduate students who are current students at Hertfordshire and those who are not.

Students who are interested in working on a project should email the project supervisor as early as possible and copy in the research tutor (Sugata Kaviraj; s.kaviraj@herts.ac.uk). In their email, students should include a short statement explaining why they are interested in the project and, if possible, attach a short CV. They are welcome to express interest in multiple projects (although they will typically work on one project, usually over the summer period). Supervisors will then set up an informal chat to discuss details of the projects with prospective students after which students will be expected to make project selections. Some limited funding may be available and students will be advised of the details after they apply.


The Coronet Cluster: an unruly stellar nursery

In this project, we will use infrared, X-ray, and radio data to peer into an otherwise opaque molecular cloud to directly observe nascent young stars. While 'growing up', these accrete more and more mass from their surroundings, and they rapidly show signs of magnetic activity. Both effects manifest themselves in unruly flaring variability in different wavebands. In an instructive example of the power of multi-wavelength astronomy, we will make use of a unique set of multi-epoch observations at infrared and X-ray wavelengths to systematically quantify for the first time the incidence of far-infrared variability in young protostars and any correlations with X-ray and radio flares. Initially focusing on data obtained with the Herschel Space Observatory, this project will develop basic data analysis skills for multi-wavelength observational astronomy and time domain studies. This could be done as an ideal team project for a group of undergraduates, and it is scalable into a full research project.

Accompanying Astronomy Picture of the Day: https://apod.nasa.gov/apod/ap070921.html

Appropriate for undergraduate students in their 2nd year and above.

Dates: 4-8 weeks (flexible)

Supervisor details: Dr Jan Forbrich, j.forbrich@herts.ac.uk, room 2E65


The influence of massive stars in Milky Way type galaxies

Spiral arm galaxies, such as the Milky Way, host numerous clusters of massive stars. These stars interact violently with the surrounding interstellar medium and collectively drive expanding shells of material, so-called super-bubbles, which can be observed. These super-bubbles are thought to be energetic enough to drive galactic outflows and pollute the inter-galactic medium. In this project, we will first use Python to visualise hydrodynamic simulations of a Milky Way type galaxy. These simulations investigate the possibility of subsuming scales below 100pc by an effective super-bubble model to simulate the stellar feedback from a massive star cluster. We will calculate mass outflow rates from the spiral arms in the galactic disk, as well as other useful quantities such as the energy outflow rate. We will identify how the galactic mass outflow rate depends on the location of the super-bubbles within the galactic disk. These simulations can then ultimately be compared with observations of known outflow rates.

Appropriate for undergraduate students in their 2nd year and above.

Dates: 4-8 weeks (flexible)

Supervisor details: Dr Donna Rodgers-Lee (room 1E72, d.rodgers-lee@herts.ac.uk) & Dr Martin Krause (room 1E57, m.g.h.krause@herts.ac.uk)


The WEAVE-LOFAR survey

(This project is full and is no longer accepting students)

The WEAVE LOFAR survey will obtain optical spectroscopy of very large samples of radio sources using the WEAVE instrument, which when it is completed in 2019, will be able to obtain 1,000 optical spectra every hour. These spectra can be used to obtain redshifts (i.e. distances) for the very distant radio sources that we target, which in turn enable us to learn about star formation, black holes and the evolving relation between them over the latter half of cosmic history. In this project, the student will use the latest simulated WEAVE LOFAR data to measure radio luminosity functions (i.e. the space density of star-formation and black-hole dominated galaxies) and how they have evolved. These results can also be compared with the latest cosmological simulations and ultimately inform our understanding of the complex interplay between these two processes which drive galaxy formation and evolution.

Appropriate for undergraduate students in their 2nd year and above.

Dates: 4-8 weeks (flexible)

Supervisor details: Dr Dan Smith, d.j.b.smith@herts.ac.uk, room 2E65


Searching for the signatures of the first supernovae from Galactic Archaeology surveys

Recently, Galactic Archaeology surveys.(such as GAIA-ESO or HERMES-GALAH) have provided detailed elemental abundance patterns of million of stars in the Milky Way Galaxy. In this project, students will compare the observed elemental abundance patterns to the nucleosynthesis yields of core-collapse supernovae, in order to search for the signatures of the first stars. Students will develop a small program for the chi-square fitting, and produce figures using Python or other graphical tools.

If students are interested, they can also test the Python version of our chemical evolution code. Basic skills in programming are required.

Appropriate for undergraduate students in their 2nd year and above.

Dates: 4-8 weeks (flexible)

Supervisor details: Dr Chiaki Kobayashi, c.kobayashi@herts.ac.uk, room 1E51 & Dr Fiorenzo Vincenzo (f.vincenzo@herts.ac.uk)


Revealing atmospheric structure, clouds and chemistry of a young planetary mass object

Spectral inversion techniques, also known as atmospheric retrievals, were first developed for remote sensing the Earth’s atmospheric conditions, and have now been applied to Solar system planets, exoplanets and brown dwarfs. In this project, the student will use Ben Burningham’s atmospheric retrieval framework (“Brewster”: http://adsabs.harvard.edu/abs/2017MNRAS.470.1177B) to study the atmospheric properties of a planetary mass companion to the active M dwarf binary Ross 458. Previous investigations have suggested that Ross 458C’s near-infrared spectrum is impacted by condensate clouds. This will be tested using retrievals via Bayesian model selection. The [C/O] ratio of Ross 458C will also be estimated under assumption of chemical equilibrium, and compared to the primary star system.  This will involve some basic programming in Python, and editing shell scripts to run code on the UH high performance computing cluster.

Appropriate for undergraduate students in their 2nd year or above.

Dates: 4 - 8 weeks (flexible)

Supervisor details: Dr Ben Burningham, b.burningham@herts.ac.uk, room 1E50


Constraining cosmology with clusters

Clusters of galaxies are the largest bound structures in the Universe, and represent fluctuations at the tail of the matter power spectrum. As such, they are powerful cosmological probes. This project will attempt to constrain sigma_8 – the amplitude of mass fluctuations on a scale of 8 megaparsecs – using a large sample of optically selected clusters of galaxies from the Sloan Digital Sky Survey and the Planck weak lensing map of the cosmic microwave background. A further challenge will be to attempt to constrain the total neutrino mass by investigating the cluster bias-mass relation... which would be a really cool result.

Appropriate for undergraduate students in their 2nd year and above, with some Python knowledge handy for the analysis.

Dates: 4-8 weeks (flexible)

Supervisor details: Dr Jim Geach, j.geach@herts.ac.uk, room 2E72B


Combinatorial Geometry and Physics

Combinatorial geometry asks interesting questions that often have an immediate physical relevance. An example is the Illumination Problem: What is the smallest natural number of directions sufficient to illuminate the boundary of a convex shape? Illumination is provided by parallel beams in each direction. Beyond simple illumination, we have the casting of shadows and the quantification of the information embedded in the shadow. The aim of this project is to bring the supervisor up-to date in this field using as a starting point the beautiful book of Boltjansky and Gohberg in 1985 – Results and Problems in Combinatorial Geometry.  You will read through this, find something that interests you and then we will see if we can concoct a problem that has an interesting contemporary physical application. There are no guarantees of success but it is beautiful maths!

Appropriate for undergraduate physics students in their 2nd year and above who enjoy mathematics.

Dates: 4-6 weeks (flexible)

Supervisor details: Dr Jim Collett,  j.l.collett@herts.ac.uk , room 1E70


Spectral analysis of nearby stars

The aim of the project will be to analyse high resolution high signal-to-noise spectra of planet and non-planet hosting nearby stars. The student will need to acquire familiarity with the Linux operating system and Python.

Appropriate for undergraduate students in their 2nd year or above.

Dates: 4 - 8 weeks (flexible)

Supervisor details: Hugh Jones, h.r.a.jones@herts.ac.uk, room 2E55


Photometric periods from Gaia DR2

One of the primary issues in the search for planets around nearby stars is the potential confusion of signals with stellar activity cycles. The Gaia satellite has recently made its second data release. This includes high quality light curves for variable sources. The task will be to find the light curves for objects with high precision radial velocity data and search for periodicities in the overlapping data sets.

Appropriate for undergraduate students in any year.

Dates: 4 - 8 weeks (flexible)

Supervisor details: Hugh Jones, h.r.a.jones@herts.ac.uk, room 2E55


Exoplanet software

The project is to develop a website dedicated to the easy follow-up of potential nearby transiting exoplanets which are being found by a variety of space missions. Although many candidates are being found there is a significant practical task to identify the most suitable ones for immediate follow-up. The project is aimed at a website and user guide to support the confirmation and follow-up of exoplanet candidates from new space missions.

Appropriate for undergraduate students in any year.

Dates: 4 - 8 weeks (flexible)

Supervisor details: Hugh Jones, h.r.a.jones@herts.ac.uk, Room 2E55


Uncovering nearby hidden brown dwarfs with WISE

The list of the Sun's nearest neighbours has been growing for thousands of years, with brighter neighbours discovered further back in time. Alpha Centauri AB (G/K type) for instance was listed in the 2nd century star catalogue of Ptolemy, with the cooler fainter Barnard's star and Proxima Centauri discovered ~100 years ago. More recently, as new telescopes provide greater sensitivity and longer wavelength coverage, brown dwarf discoveries have jumped into the chart e.g. Luhman 16, WISE 0855-0714, and Epsilon Indi AB. Nearby systems are important astronomical targets for studies of stellar/substellar physics and exoplanet systems. And there is even a theory that the Sun may posses a previously unseen brown dwarf companion in a very wide orbit (Nemesis). Expectations remain that a significant populations of local stars and brown dwarfs are currently unknown. WISE is a space-base mid-infrared telescope launched in 2010, that has been imaging the sky on a 6-monthly basis providing multiple coverages (epochs) that offer the best sensitivity to the coolest nearby brown dwarfs. However, WISE has low spatial resolution, with sources being several arcseconds across. This leads to serious source-crowding in regions such as the galactic plane and centre, towards which nearby brown dwarfs could be hiding undiscovered. WISE's latest Spring data release will provide the largest number of epochs yet, and in this project you will use this multi-epoch data to hunt for nearby high proper motion brown dwarfs in crowded sky. You will utilize a range of methods to combine the multi-epoch data, and visually isolate the signatures of moving brown dwarfs from the crowded background. And you will also test your methods on known objects, to assess their effectiveness in different situations. New discoveries would be exciting objects, and be fast-tracked for observation using the group's large telescope programmes.

Appropriate for undergraduate students in any year.

Dates: 4-12 weeks (flexible)

Supervisor details: David Pinfield, d.j.pinfield@herts.ac.uk, room 1E66


Exoplanet and brown dwarf studies using Gaia wide binaries

Gaia is an ESA cornerstone mission to measure the distances and motions of approximately a billion stars, and is revolutionizing many fields of astronomy. The 2nd Gaia data release has just gone public, and represents the biggest advance that Gaia will provide. The Herts low-mass group is using Gaia to seek wide binary systems that form the basis for a number of studies: (i) Ultracool dwarf companions to Gaia stars have their properties calibrated by the primary, becoming "benchmark objects" that reveal ultracool atmosphere physics. (ii) Cool objects close to wide Gaia binaries are likely to have been ejected from orbit around one of the binary components, and the identification of such objects would reveal brown dwarfs and giant planets that were previously hidden as orbital companions. (iii) Wide binary stars have common age and composition, with stellar activity dependent on age. But exoplanets in close orbit may tidally interact with their host stars (increasing their activity), and they may also accrete onto their host star's atmosphere changing the composition. Wide binary stars whose components have different composition and activity levels could thus show the "smoking gun" for exoplanet interaction and accretion. In this project you will develop a tool for determining optimal spectral types and classifications for Gaia stars based on all the available data. You will then construct a sample of wide binary systems, i.e. pairs of Gaia stars with ~arcminute separation and a shared distance and proper-motion. As time allows, you will have the opportunity to study a subset of these binaries in the context of one of the group projects.

Appropriate for undergraduate students in any year.

Dates: 4-12 weeks (flexible)

Supervisor details: David Pinfield, d.j.pinfield@herts.ac.uk, room 1E66