Askaryan Under ice Radio Array March 1 st

Askaryan Under ice Radio Array March 1 st 2007, Hagar Landsman Future Directions Radio Hagar Landsman Science Advisory Committee meeting March 1 st, Madison

Why Ee. V neutrinos ? – GZK cutoff • No Cosmic rays above ~1020 e. V • High energy neutrinos – Study of energetic and distant objects (Photons attenuation length decrease with energy) – Study highest energy neutrino interaction – Point source – Exotic sources – The unknown The predicted flux of GZK neutrinos is no more than 1 per km 2 per day. …. but only 1/500 will interact in ice. Ice. Cube will measure ~1 event per year. We need a 1000 km 3 sr to allow: Statistics, Event reconstruction ability, flavor id March 1 st 2007, Hagar Landsman

• A Less costly alternative • Larger spacing between modules • (Large Absorption length) • Shallower holes • Narrower holes • Good experience • Experimental measurement of RF enhanced signal from showers • Technology used for : RICE, ANITA, and other March 1 st 2007, Hagar Landsman ) km io ( es . 5 d -2 Ra 5 1. l , Ice b ub no b k ai B r( al ) m 1 k optic al e at W 1012 s ubble Ice, b ) 9 m (0. 13 k 1014 10 1015 Energy (e. V) 1016 Astro-ph/9510119 P. B. Price 1995 • Askaryan effect Coherent Cherenkov RF emission of from cascades. • Radio emission exceeds optical radiation at ~10 Pe. V • Completely dominant at Ee. V energies. • Process is coherent Quadratic rise of power with cascade energy Effective Volume per Module (Km 3) Why Radio?

Ice. Cube • • • ANITA Pressure vessel Connectors Main board DAQ Cables Holes LABRADOR chip: • • low power consumption low dead time large bandwidth cold rated RICE Antennas Data analysis Electronics and control KU March 1 2007, Hagar Landsmanof University Maryland Delaware st University of Hawaii Kansas University Penn State University of Wisconsin - Madison

surface junction box Counting house The Radio Cluster Each unit is composed of : − 1 Digital Radio Module (DRM) – Electronics − 4 Antennas − 1 Antenna Calibration Unit (ACU) Signal conditioning and amplification happen at the front end, signal is digitized and triggers formed in DRM A cluster uses standard Ice. Cube sphere, DOM main board and surface cable lines. Use a DOM-MB as communication and power platform. Advantage: get a “free” design for power, comms and time stamping. March 1 st 2007, Hagar Landsman Not to scale!

Digital Radio Module (DRM) To ce rfa su To antenna an To ten na Modified glass sphere 6 Penetrators: 4 Antennas 1 Surface cable 1 Calibration unit MB (Main board) Communication, timing, connection to IC DAQ infrastructure, Radio Boards Cal To ibr a un tion it To antenna March 1 st 2007, Hagar Landsman To na ten an UHF Sampling, Triggering, Digitizing, data processing, trigger banding, interface to the mb

Sealing the DRM Antennas Going down ROBUST TRACR DOM-MB Metal Plate Hagar Landsman March 1 2007, st DRM electronics Metal can /w electronics

Antennas 17 cm March 1 st 2007, Hagar Landsman

Tests and calibration Front end electronics testing March 1 st 2007, Hagar Landsman Anechoic antenna chamber tests

Integrated cluster Testing • Testing clusters down to -45 o • On ice pre-deployment testing March 1 st 2007, Hagar Landsman

Waiting to be deployed Antenna cables Pressure vessels Antennas DRM March 1 st 2007, Hagar Landsman

AURA GOALS for 06/07 season The • • • five point goals were defined in July 06 PDR Assess the suitability of the Ice. Cube environment Receive, amplify, and digitize over 0. 2 to 1 GHz Antenna trigger and timing Multiple cluster trigger Measure RF noise beyond RICE frequency (600 MHz) Deploy a minimum of two clusters at two different depths We have successfully deployed 3 clusters. All 3 clusters are collecting data. Installation and operation did not conflict with Ice. Cube’s string installations or data acquisition. We have the in ice hardware needed to achieve those goals. March 1 st 2007, Hagar Landsman

Deployment this season 78: “rock” , 1 st , Deployment, Deep 4 Receivers, 1 Transmitters 57: “scissors”, 2 nd deployment, Shallow 4 Receivers, 1 Transmitters 47: “paper” 3 rd Deployment, Deep 1 Transmitter March 1 st 2007, Hagar Landsman

Short term plan In Ice units – Calibration using ACU – Calibration using RICE transmitters – Tests of mb-TRACR operation • Triggering • Timing • Data rates • Durability – Wave forms characterization – Ice Suitability – RF noise March 1 st 2007, Hagar Landsman

Short term plans Next year deployment Building and deploying ~10 additional units • • Intermediate scale GZK detector Coincidence with Ice. Cube. Ice RF survey On the way of a GZK detector: New designs, Independency from Ice. Cube. – Keep using Ice. Cube infrastructure. – Based on lessons learned this season improve: • • Design of the cluster, Antennas and front-end. Data acquisition and testing tools. Deployment and on Ice handling Power distribution and control – Simulation studies • Geometry, antenna design, wave propagation • detector simulation March 1 st 2007, Hagar Landsman

The next step 10 km scale hybrid GZK detector – Acoustic/optical/RF Challenges: • Independent detector – Power distribution and DAQ over large distances. – New radio DAQ. Keep using mb utilities? – Smaller holes – Packaging, cabling, deployment • R&D for antennas design, RF electronics, triggering. • Simulation studies • Interface with optical and acoustic modules. March 1 st 2007, Hagar Landsman

PROPOSAL • Proposal was submitted: 2 years R&D, simulation, detectors. • Document posted under “additional materials” in docushare. • Additional funding sources have been used for recent design and production of first radio clusters. March 1 st 2007, Hagar Landsman

Summary • Last Season 3 Radio clusters successfully deployed • In the next years Further DRM development and deployment • Far Future Towards >100 km 2 scale detector March 1 st 2007, Hagar Landsman

End March 1 st 2007, Hagar Landsman

Front end electronic − Signal amplification and filtering. − Electronics inside a metal pressure vessel − Each unit weight 20 kg March 1 st 2007, Hagar Landsman

Askaryan effect Neutrino interact in ice showers Many e-, e+, g Interact with matter Excess of electrons Cherenkov radiation Coherent for wavelength larger than shower dimensions Moliere Radius in Ice ~ 10 cm: This is a characteristic transverse dimension of EM showers. <>RMoliere (RF), coherent P N 2 March 1 st 2007, Hagar Landsman Hadronic (initiated by all n flavors) EM (initiated by an electron, from ne) Vast majority of shower particles are in the low E regime dominates by EM interaction with matter Less Positrons: Positron in shower annihilate with electrons in matter e+ +e- gg Positron in shower Bhabha scattered on electrons in matter e+e- e+e. More electrons: Gammas in shower Compton scattered on electron in matter e- + g e- +g Charge asymmetry: 20%-30% more electrons than positrons.

• Antennas KU • Front end electronics UMD, KU, Hawaii • DRM Electronic component: – – Digitizer Hawaii data control KU main board UW Power converter bartol • Electronic integration KU • Connectors, cables, sphere, pressure vessel, installation UW • Detector integration, testing, packaging UW • Firmware/software KU, UW, PSU March 1 st 2007, Hagar Landsman