IceCube EHE Event search with 9 strings

IceCube EHE Event search with 9 strings IceCube/EHE Search/Analysis

Level-1 EHE Sample: year 2006 Basic Plots

Basic properties

Run ID and Event ID
The first run in this plot started at 6/2/2006 and the last run at 11/20/2006.

Run ID and the event start time in second since current UTC year (2006) started

N channel distribution
all samples, including Nch less than 80

x and y distribution of the center of brightness

Duty cycle... is IceCube hard worker?

Livetime (unit is 0.1[ns]) of each files: (defined as the end time of the last event minus the first event start time in the file)
processed number of file (with non-zero livetime) is 1636.
mean number of livetime times number of file corresponds to total livetime in 0.1ns.
this corresponds to 127.7 days!
Roughly, if we could consider this sample is taken from 6 months period, from June to Nov, 21.28 days/month.

To get duty cycle since run ever has started and the last run in the all files,
need to know the first event start time and the end time of the last event.
following is the first and last 3 events of start and end times.
this gives us a 166.9 days.
Using this number and above livetime value we get 76.5% of duty cycle!

EHE Event Interval From Previous Event

Time interval from the previous event

Time interval from the previous event in log

EHE Event Trigger Rate

Time dependence of EHE event trigger rate

Energy!! ~ NPE

In the following, only the cut applied is Nch>80

NPE distribution

Getting steeper! - NPE distribution with simple fit.
fit_function(log10(NPE))=[0]-[1]*log10(NPE).
gammas in plot corresponds to [1]+1
as dN/d(logE)=EdN/dE

EHE background region
Found 511 events over the time priod -- 127.7 days of live time.
this is consistent with our initial study of DC1 MC data with corsika extrapolation based atmospheric muon weight.
however note that because the number of FADC readout bins has been reduced, current estimated NPE corresponds to the same energy is also reduced.