LOFAR-UKA proposal to STFC PPRP

PI Professor Rob Fender (Southampton)

On behalf of the following consortium:

Liverpool John Moores University, The Open University, The Universities of Cambridge, Cardiff, Durham, Edinburgh, Glasgow, Hertfordshire, Manchester, Oxford, Portsmouth, Southampton, Aberystwyth, University College London, The Rutherford-Appleton laboratory

+ Universities of Kent and Sussex, QMU and ATC contingent on SUPA2 and SEPNET funding

A ‘next generation’ radio telescope under construction in Europe, operating in 30—240 MHz frequency range. Thousands of small dipoles (no dishes) connected by high-speed internet to a central processing facility.

Orders of magnitude improvement in sensitivity and survey speed compared to previous observation at these frequencies. Extremely diverse science case and user community.

Pathfinder for the low-frequency component of the Square Kilometre Array (SKA), a key component of the RCUK large facilities roadmap.

LOFAR science case

LOFAR Key Science Projects

• Epoch of Reionisation (EoR)

• Deep extragalactic surveys

• Radio transients and Pulsars

• Cosmic rays and particle astrophysics

• Solar physics

• Cosmic Magnetism

Guaranteed time will be allocated to these KSPs for the first ~5 years of LOFAR operations, with a steadily increasing fraction of open time.

The Epoch of ReionisationReionisation of the Universe, following the ‘dark ages’, occurred 6 < z < 12

This redshifts the 21cm HI line to the LOFAR frequency range, allowing mapping of EoR signal

Key issue is removal of radio foreground

Deep extragalactic surveysLOFAR will detect 108 extragalactic radio sources (primarily starburst galaxies) fantastic resource for cosmology

Requires international baselines to fulfil its potential

Radio Transients and PulsarsLOFAR will scan a large fraction of the entire sky ~daily, providing a Radio Sky Monitor for the first time.

Combined with targeted surveys, we will study

Accreting black holes / neutron stars

Pulsars

Extrasolar planets

‘LIGO events’ + … ?

Collaboration with LT already established

Cosmic rays / particle astrophysics

CR produce radio pulse

High-energy particles (e.g. neutrinos) can produce radio burst by interacting with moon

Cosmic magnetismLOFAR polarisation surveys will allow unprecedented mapping of large-scale magnetic structures within our galaxy and other galaxies

This KSP has the practical task of making LOFAR polarisation calibration work

Solar physicsLOFAR is a fantastic tool for monitoring the Sun as well as the solar wind / ejections and their propagation out through the inner solar system

Stand-alone science

LOFAR stations can be used as stand-alone observatories for monitoring variable sources e.g. pulsars, solar activity, radio transients

The LOFAR-UK white paper

On Feb 8 we published the LOFAR-UK white paper on astro-ph (see also LOFAR-UK website www.lofar-uk.org)

astro-ph/arXiv:0802.1186

LOFAR-UK White Paper: A Science case for UK involvement in LOFAR

The need for long baselines

LOFAR with pan-European baselines – of which LOFAR-UK will be a key part – will have ten times better angular resolution than the Dutch LOFAR alone.

This dramatically improves LOFAR’s ability to make deep extragalactic surveys due to the confusion limit

It also allows spatially resolved imaging of relativistic jets, the Sun, galactic structure, clusters of galaxies etc.

LOFAR-UK are not limited to long-baseline only science!

LOFAR technical case

Low-band antennae (LBA)

30—80 MHzDigital beamforming at station level

High-band antennae (HBA)

120—240 MHzArranged in 5x5 HBA tiles

Analogue beamforming at tile level

Inbetween: FM radio band

Single dipoleStation + beamforming

Correlation of different stations

Multiple beams

BlueGene

How LOFAR works in a nutshell

Latest LBA results

Three entire hemisphere images

Data reduction / analysis by prototype of final software

More than 400 sources detected (c.f. RXTE ASM)

HBA CS1 image

4 tiles + 12 individual HBAs

500m max baseline

Observing frequency 125—175 MHz

Cas A removed to ~1% level

0.5 Jy r.m.s.

Red squares sources from 4C radio catalogue

The complete LOFAR will havex 500 collecting areax 6 bandwidthx 2000 baseline

E(uropean)-LOFAR,

The SKA

and

LOFAR-UK

E-LOFAREuropean expansion is well-funded

LOFAR-NL

ASTRONThe Observatory

ARC + DMT(with UK presence)

Universities36—50

LOFAR-UK1—4

FLOW1

GLOW4—7

SLOW1

Also Italy, Poland, Austria, Ukr.

(Fender PI on FP7 E-LOFAR proposal)

LOFAR as a SKA pathfinderThe Square Kilometre Array is one of just two astronomical facilities in the RCUK large facilities roadmap

The SKA will have three different antenna systems sharing a common infrastructure:

Low freq dipoles

Intermediate freq tiles

High freq dishes

LOFAR is the only fully-funded pathfinder for the Low freq component of the SKA (cf MWA, LWA), and is the only SKA pathfinder of any sort under construction in Europe (cf ASKAP, MeerKAT)

Southampton

Oxford

Portsmouth

UCL/MSSL

Hertfordshire

Cambridge

LJMU

Durham

Edinburgh

Glasgow

SUPA2

LOFAR-UKFormed in 2004

£600k raised in institutional contributions, plus donations of land at 4 sites

Cardiff

Aberystwyth

Manchester

RAL

O.U.

Very broad support extending beyond the traditional radio astronomy institutes

SEPNET

Chilbolton: 600 km baseline (RAL/STFC land)

Lords Bridge: 450 km baseline (U. Camb land)

Jodrell: 650 km baseline (U. Man land)

Edinburgh: 850 km baseline (U. Edinburgh land)

LOFAR:UK Proposed station sites

Using LOFAR-UK funds already raised, we have agreed first station purchase with ASTRON

(to be one of the three stations in England – all of these have been tested by ASTRON technical team)

Data connections to NL via SuperJanet 5 +commerical

What is return for UK investment?A disproportionately large amount of science

• Epoch of Reionisation (EoR)

• Deep extragalactic surveys

• Radio transients / Pulsars

• Cosmic rays

• Solar physics

• Cosmic Magnetism

PLUS vital training in preparation for development of SKA

Core team involvement

Major involvement / board level

Overall leadership (2/3 board)

Core team involvement

Major involvement / board level

Core team involvement

This large level of involvement and leadership is based upon delivery of 4 LOFAR-UK stations

CostsThe project has a base cost of £4M in two major subsystems

Including Working Allowance and Risk £5M

Costs to be noted

• £600k already raised by consortium

• SEPNET: £2.15M astro bid, focussed on LOFAR

- £148k earmarked for hardware at Chilbolton

• SUPA2: £500k requested for LOFAR station at Edinburgh

NB1: we already have quote for all station costs except HBAs, so risk on hardware costs is reduced

NB2: commitment to spend on further UK stations probably needs to be with ASTRON by end 2008

£267k

£200k

£386k

£407k

£972k

£469k

£862k

£998k

£550k ‘in the bank’

SUPA2 contrib. subtracted from I2

ManagementProject manager to be hired (at 50%)

Existing Management to become the LOFAR-UK board of University members

STFC steering committee to be established

Meetings:

Management – monthly

Board – 6 monthly

SummaryLOFAR is a fully-funded ‘next generation’ radio telescope and SKA pathfinder under construction in The Netherlands

Expansion of the array across Europe is essential to maximise its potential, and is already part-funded in Germany, France, Sweden

For a base cost of ~£4M LOFAR-UK will make the UK a major partner in LOFAR, providing access to breakthrough science as well as training of people in preparation for the SKA.