The UK ACoRNE Group Present Projects and Future Plans

1. Sean Danaher Northumbria University sean.danaher@unn.ac.uk The UK ACoRNE Group Present Projects and Future Plans J. Allen, R. Binns, S. Danaher, J. Perkin, C.J. Rhodes, T. Sloan, L.F Thompson, D. Waters + P. Doust (ISVR Southampton) Acoustic Cosmic Ray Neutrino Experiment ARENA Workshop

2. Summary • UK Group Funded • MC simulation studies • Energy Deposition Simulator • Acoustic Parametric simulator • Upgrade of Rona • Future Plans • Conclusion ARENA Workshop

3. UK Group Collaboration Funded for 3 years Jointly by PPARC and the MoD OKd Sept ’04 In place Feb ’05 • RA Job advertised ARENA Workshop

4. 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 Rationale Monte Carlo Studies Corsika Geant IV • Full Amplitude and Phase calibration of Array • Pulse Simulator • Parametric Acoustic Simulator • Amplitude and Phase Responses of system Acoustic Integrals Improve speed Include fluctuations Real attenuation Data Gathering and analysis Gather a large dataset of “unfiltered” data Use numerous techniques e.g. Signal processing classification algorithms to separate signal from noise and background Butterworth Filter pulse Response Understand scaling to large arrays Be able to make recommendation for a full size experiment within 3 years Saund light bulb time (ms) ARENA Workshop

5. Shower Simulation Studies • Using GEANT IV and CORSIKA to model the shower shape both Longitudinal and average Radial • Wish to extend to E(r,l) Radial distribution as a function of shower age • Use E(r,l) to design an accurate simulator ARENA Workshop

6. Acoustic Detection Principles • Energy must be deposited over the same volume as the shower • On axis pulse approximates derivative of cross section of shower (a few cm) • Angular Spread depends on wavelength the length of the shower (/d~0.15/10 ~1O) • Energy must be deposited within c 10s • (100kHz) ARENA Workshop

7. LASER Light Deposition Simulator Gaussian Lateral distribution, Exponential longitudinal decay Absorption Coefficient of “pure” sea water 0.7 0.6 >1J in Green expensive! Use optics to spread beam. Access to MoD laser (5J at 527nm) 0.5 0.4 High Power Leds 100ns rise time 5W continuous in Green Pulsing Circuits Absorption Coefficient(m-1) 0.3 0.2 0.1 Xenon Flash Guns 1000J available White. Use focussing optics to mimic spread of Shower. 0 400 450 500 550 600 650 700 Wavelength (nm) ARENA Workshop

8. Acoustic Parametric Simulator Receiver equalisation Output equalisation (Analogue) Wideband power amplifier Surface anechoic cladding. • Can put bipolar pulses in water • Can retrieve bipolar shape • Rona array to be categorised over the summer • Investigating linear hydrophones 1m D140 Hydrophone 2m D17 TX 5m Storage Oscilloscope Electrical input signal. Input equalisation (Analogue) Signal generator HF monitor hydrophone. Electrical input signal. Unequalised transmitted acoustic waveform. LF monitor hydrophone. HF monitor hydrophone. LF monitor hydrophone with equalisation. Equalised transmitted acoustic waveform. P Doust ISVR Southampton ARENA Workshop

9. Acoustic Parametric Simulator II The Group has acquired a line array this can be used to “beam form” the sound into the “Pancake” String Hydrophones also under investigation Can Also be used for beam-forming (in receive mode) Factor of at least 8dB ARENA Workshop

10. Simulated Hydrophone signal 25 20 15 10 Amplitude (Arbitrary) 5 0 -5 -10 -15 25 30 35 40 45 50 Time (eq. cm) Sheffield Tank • Currently commissioning • Hydrophones • Data Acquisition system • NI DAQ Card-6062E (for PCMCIA) • 500 kS/s, 12-Bit, 16 Analogue Input • B&K 8104 Hydrophone • (4.0 dB) 0.1 Hz to 80 kHzwith B&K Amplifier ARENA Workshop

11. Rona Hydrophone Array • MoD facility in North West Scotland • An array of high sensitivity hydrophones with a frequency response appropriate to acoustic detection studies • Existing large-scale infrastructure including DAQ, data transmission, buildings, anchorage • Phase to be calibrated in near future • PPARC/MoD funding permits us to upgrade Data Acquisition system there to permit several weeks’ worth of unfiltered data to be recorded • Provides an excellent test-bed for the “simulator” ARENA Workshop

12. Noise levels for January x 104 Noise levels for April x 104 6 8 5 6 4 Frequency Frequency 3 4 2 2 1 0 0 20 30 40 50 60 20 30 40 50 60 Noise(dB) Noise(dB) x 104 Noise levels for July Noise levels for October x 104 8 10 8 6 6 Frequency Frequency 4 4 2 2 denz(z) match(z) pulse 0 0 20 30 40 50 60 20 30 40 50 60 numz(z) Noise(dB) Noise(dB) Acoustic Pulse Scope Inverse Filter (pre-whitening) numz(z) denz(z) Discrete Filter White Noise Source Knusden Noise and Matched Filtering Is one quiet day better than many noisy days? • Noise driven primarily by sea state • Can Model Noise Spectrum as H(z) • Design optimal Matched Filter For a given site can model sea state noise using a Rayleigh Distribution ARENA Workshop

13. Matched Filtering • The signal sits on a flat noise background varying only in magnitude according to sea state • Apply matched filter ~3 times noise reduction • Limit PFA to 1 signal in 10 yrs due to noise with 5 fold coincidence – gives us a threshold with POD 50% of typically 35 mPa ARENA Workshop

14. Advanced Signal Processing Techniques • Wavelets • Adaptive Fuzzy Clustering • Subspace Optimisation (SVD) • Artificial Neural Networks • MLP • Kohonen • LVQ • Adaptive filtering (Wiener etc) ARENA Workshop

15. The Future? • Rona very useful as a test bed • But ideally • Hot, Salty, Deep, low average wind velocity low shipping noise E Med, Mid Atlantic? Need multi-parameter detector with data fusion? Need an EU/US/Russian Collaboration? ARENA Workshop

16. ARENA 2006Newcastle UK ARENA Workshop