SADE ANITA Monte Carlo(SAM) Test Results Amir Javaid University of Delaware

Two important plots Black(Auger), Blue (Gaisser and Stanev(AGASA))

Topics ● Introduction to SADE ANITA MC(SAM). ● List of test runs ● Phase space for event generation ● Event geometry analysis ● Electric Field at point payload analysis ● Events Above analysis threshold ● Correlation of polarization and ray launch angle with Electric Field ● Effective Area and Event Rate estimation. ● To do list

Introduction to SADE ANITA MC(SAM) ● The goal of SADE ANITA MC is to estimate the sensitivity of ANITA 1 & 2 for neutrinos and cosmic rays. ● For realistic ray tracing SAM uses depth dependent refractive index and attenuation models. Attenuation model still needs more improvement. ● Ray tracing is done using geocentric and topocentric (local) coordinates. ● AVZ parameterization is used to simulated neutrino and cosmic ray events. Cosmic ray events uses 10% Primary energy proxy parameterization. Electric field parameterization for cosmic rays is under construction. ● Cosmic ray shower core are generated just below the surface. ● Flat ice/air and bedrock surfaces with no roughness are used. Surface slope and roughness implementation is under construction. ● Bedrock is assumed to be perfectly reflective. ● ANITA triggering model is incorporated in the MC but not properly tested yet.

List of Test Runs ● Cosmic rays core shower case 1. – Ice depth 0.5km & surface elevation 0km. ● Cosmic rays core shower case 2. – Ice depth 1.5km & surface elevation 3.5 km. ● Cosmic rays core shower case 3. – Ice depth from the Bedmap and surface elevation from the Ramp data with 100 m resolution. ● Neutrino case 1 – Ice depth 0.5km & surface elevation 0km. ● Neutrino case 2 – Ice depth 1.5km & surface elevation 3.5 km.

Phase Space for Event Generation ● Payload at -89degree latitude and -180 degree longitude. ● Event throw radius was 900 Km ● Simulation kept events for which payload height >100m in event Topocentric coordinates ● Throw Azimuthal Angles were degrees. The zenith angles for neutrinos were degrees and for Cosmic rays degrees. ● The plots on the right show a sample of generated events

Event Geometry Analysis The set of plots shown here are from Cosmic ray case 2 and 3.They present distributions of the following parameters involved in the simulation. ● Launch angle measure from shower axis. ● Arriving angle is the zenith of signal in payload local coordinates. ● Fresnel Factor ● Ray path in ice

Electric Field at point payload Analysis The plot on top right show the Electric Field distribution for different cases. The plot on the right bottom show a distribution of triggered events from an icemc run for 10^19eV run. The vertical (Red line) on both the plots shows the threshold called scaling threshold used for scaling to higher energies. This will act as a proxy trigger for analysis. To check the distribution of events I have chosen another threshold called the analysis threshold which is 10^-5mV/cm/GHz (Black line).The Following are the counts of events that passed the analysis threshold.

Events Above Analysis Threshold The easting and northing histograms on the right show the events above the Analysis threshold of 10^-5 mV/cm/GHz threshold in blue. The histogram at the bottom show these events in dark red.

Correlation of polarization and ray launch angle with Electric Field

Effective Area and Event Rate Estimation To get the effective area plot shown on top right. I estimated Efield triggering threshold value from a10^19eV icemc run which is Eth =5.5*10^-7 V/m/MHz approx. Utilizing the Efield distribution for events above my analysis threshold for 10^19eV Cosmic ray run I scaled the energy by the following formula. E(scaled)=(Eth/E)*10^19eV Then I weighted the CR histogram events by total number of CR simulated events and then multiplied by total geometric area *10^15 cm^2 sr inside the ~500km horizon. The Cosmic ray spectrum from Auger (Black), Gaisser and Stanev(Blue)) (AGASA) was used to generate the event rate spectrum plot. ● Total event rate(Auger spectrum)=9.538*10^-7 events/second ● Total event rate(Gaisser and Stanev spectrum)=4.519*10^-6 events/second

To do List ● Cosmic ray Electric Field parameterization. ● Testing of SAM with realistic ANITA trigger configuration ● Implementation of the surface slope and roughness for ice/air and bedrock. ● Get a more realistic bedrock reflectivity model.