Speaker
Description
The LOw Frequency ARray (LOFAR) has been operating at the longest radio wavelengths since 2010. It has opened up a wide range of scientific applications, from ionospheric studies to mapping the largest coherent radio structures in our Universe. This was enabled by new technologies such as aperture array antenna systems, and one of the world’s fastest super-computers.
LOFAR consists of two types of antennas: Low-Band Antennas (LBA, 30 to 90 MHz), and High-Band Antennas (HBA, 110 to 240MHz). Each station has fields of both, with different HBA layout depending on the station type. Due to budget limitations LOFAR could not use all LBA at the same time, nor could LBA and HBA be used simultaneously. In just 15 years the technologies have matured, and network capabilities and compute power per euro have increased significantly. This allows for the ongoing transition to LOFAR2.0, which will increase sensitivity and bandwidth by using all LBA and HBA at once.
In addition, LOFAR had individual station clocks for all stations outside the central core (superterp). This is a key characteristic of a VLBI telescope array. With baselines of thousands of kilometers, LOFAR is in its essence a VLBI array. Though this will change in LOFAR2.0 by installing White Rabbit time keeping for all Dutch stations, the data processing challenges remain similar, especially for VLBI applications.
The future of LOFAR aims for real-time data processing in the entire observatory post-processing chain and exploiting the long baseline science, which is one of the most compute intensive use cases. LOFAR VLBI requires high resolution in both time and frequency, creating datasets of hundreds of Terabytes. An important next step for LOFAR VLBI is to improve the performance of the data flow, which is part of the LENSS proposal that was recently granted.
In this talk I will present an overview of LOFAR, the LOFAR2.0 improvements, and future steps towards further improving performance of LOFAR VLBI capabilities with LENSS.
