2nd of June
Marsfield Lecture Theatre

Programme
(Download printable ps programme & abstracts)
 
 

Abstracts
 
 

Aidan Hotan

The Latest Developments in Pulsar Research at Parkes

I will discuss recent developments, both scientific and technological, related to Pulsar research in Australia. Two new instruments have been commissioned at the Parkes radio telescope in the past 12 months and a new dual-band receiver is due for installation in December. The new hardware makes Parkes one of the most powerful pulsar research tools in the world. I will present preliminary results of several experiments that take advantage of the new instruments, demonstrating the enhanced observational capabilities they provide.
 
 

Haydon Knight, Swinburne University

High Time Resolution Studies of Pulsars

In August 2002 a new baseband recorder was commissioned at the Parkes Radiotelescope. The Caltech-Parkes-Swinburne-Recorder Mark 2 (CPSR2) samples a 128MHz band once every 8 nanoseconds, offering new insight into many aspects of pulsar astronomy. I will discuss the use of CPSR2 to search for ultrafast and highly accelerated pulsars, its use in RFI mitigation, and application of its fast sampling rate to study transient radio phenomena, such as giant pulses from the millisecond pulsar J1824-2452.
 
 

Natasa Vranesevic, University of Sydney

Challenging question on emission from energetic young radio pulsars

In the last few years number of neutron stars have been discovered with magnetic fields of magnitude only imagined by a few theorists. The previous highest measured neutron stars fields were around 10 to 13 Gauss. The Parkes Multibeam Survey has now detected a number of new radio pulsars having surface magnetic fields of near 10 to 14 Gauss, and has been particularly efficient at finding young objects in the inner Galaxy. Soft Gammma-Ray Repeaters (SGRs) and Anomalous X-Ray Pulsars (AXPs) with surface fields possibly as high as 10 to 15 Gauss, now believed to be the predicted magnetars, are even more remarkable. The circumstance that 18% - 35% of neutron stars have been detected in radio region, give us a good reason for observation throughout the electromagnetic spectrum to attain a true picture of the compact objects population. This review summarises the latest discovery of energetic young radio pulsars and open challenging question on emission from these exotic objects.
 
 

Rachel Deacon, University of Sydney

Origin of Planetary Nebulae Morphologies

I am studying a sample of 87 post-AGB stars at maser frequencies in order to determine the structure and kinematics of their circumstellar shells. The cause/s of the varied morphologies of planetary nebulae, which can be categorised as widely as elliptical, spherical, bipolar or amorphous, are as yet unexplained. Studying these precursor stars will give more insight into the processes happening.

I will summarise results so far from spectral observations at OH maser lines taken with the Parkes telescope, problems encountered, possible interpretations and future work.
 
 

Ilana Klamer, University of Sydney

Star formation in high redshift radio galaxies

An important diagnostic for exploring the star formation history in the universe is the CO molecule, whose rotational transitions are caused primarily by collisions with molecular hydrogen in dense molecular clouds. Observations of different CO transitions can tell us about the kinematics, temperature and density of the molecular clouds, as well as providing an independent tracer of the star formation rate. At high redshift (z>3.5) this has only been done for a handful of carefully selected sources with extremely large infra-red luminosities. With a complete sample of the most massive galaxies at high redshift, and access to the new 12mm system at the ATCA, we plan to study the CO(1->0) line emission at high redshift.
 
 

Jennifer Donley

Discovery of a Supermassive HI galaxy

The Parkes HIPASS and ZOA surveys are excellent tools to detect normal HI galaxies throughout the Local Universe. These surveys, however, also have the potential to uncover rare objects. I will discuss the discovery of one such object, a supermassive spiral galaxy with an HI mass comparable to that of Malin 1. This galaxy was first detected in the ZOA multibeam survey, and has since been followed-up with both the ATCA and the AAT.
 
 

Emma Ryan-Weber, University of Melbourne

Intergalactic HII Regions

We have discovered a number of very small isolated HII regions 20-30 kpc from the nearest galaxy. These HII regions appear as tiny Emission Line dots (or ELdots) in narrow band images obtained by the NOAO Survey for Ionisation in Neutral Gas Galaxies (SINGG). We have spectroscopic confirmation of 5 ELdots in 3 systems. The H-alpha luminosities of these ELdots are equivalent to the ionising flux of only 1-2 OB stars each. Two systems with confirmed ELdots have large tidal HI features. The ELdots could result from in situ star formation or ionisation by runaway B stars from a nearby galaxy. If the ELdots are ionised by stars formed in situ, they represent atypical star formation in the low density environment of galaxy outskirts.
 
 

Daniel Mitchell, University of Sydney

Dual-Reference Adaptive Filters

Adaptive filters can be used to model the radio frequency interference environment so that it can be cancelled from the astronomy signal path. The standard adaptive filter will be reviewed, and I will describe a variant which utilises an additional reference signal to improve excision. The use of a second independent reference can theoretically lead to complete cancellation. The trade-off is that the noise injected by the dual reference filter contains more power than the total residual of a single reference filter.
 
 

Anil Chandra

Remote Visualisation System (RVS)

Astronomers and astro physicists will find extremely useful a system that allows them to visualise and analyse data cubes on demand, irrespective of where in the world the data is located. The difficulties of achieving this are associated with the location, transmission and transformation of the data. How can a user interact with the data without the performance penalty typically associated with remote communication?

The Remote Visualisation System (RVS) is a software system that will work as part of the International Virtual Observatory (IVO) to provide a solution to these problems. The RVS will receive data from an independent remote data centre, transform the data and transmit formatted data to a client side application for flexible visualisation and analysis.
 
 

Aaron Chippendale

I will illustrate the effects of a variable primary beams in synthesis imaging and discuss several algorithms for accommodating them which I plan to investigate. On a second thread, I will discuss the modelling of nonlinear systems with a view to determining the spectral dynamic range of hypothetical receivers for the all sky EoR experiment.