Top > SPE, MPE Rate for Solar Event
IceTop SPE/MPE discriminator rate
The IceTop is the surface component of the IceCube neutrino observatory, is an air shower array consisting of 162 ice Cherenkov detectors, each 90 cm deep with surface area 2.7 m^2. Signals are recorded by photomultipliers in two Digital Optical Modules (DOMs) frozen into the ice in each detector. Two DOMs in a detector are typically operated at high and low gain settings to provide appropriate dynamic range.

We use counting rates from two discriminators in the high gain DOMs. They are termed SPE (Single Photo Electron), and MPE (Multi Photo Electron) for historical reasons. The SPE discriminators are actually set to thresholds ranging between 1 and 20 photoelectrons whereas the MPE threshold are all set near 20 photoelectrons. The counting rates at those SPE and MPE threshold settings range from 1.0 to 4.5 kHz.

The SPE/MPE discriminator rate plotted here is averaged data of these 4 blocks.
* SPE discriminator rates are averaged in 3.
1: first 18 high rate DOMs ( >~4kHz )
2: next 38 high rate DOMs ( >~2kHz )
3: remaining 106 DOMs
* MPE discriminator rates are averaged in 1.
Some glitches tend to be seen in SPE-1 and SPE-2.

Neutron Monitor rates & Interplanetary parameters
* South Pole Neutron Monitor Count Rate (1min).
* Solar X-ray and Proton Flux from GOES (5min), Interplanetary Magnetic Field and Solar Wind Speed from ACE (1min).

Event Plot
GLE71 (Ground Level Enhancement at May 17, 2012)
GLE72 (Ground Level Enhancement at Jan 6, 2014)
GLE73 (Ground Level Enhancement at Oct 29, 2015)NEW

Data & Links
NOAA SWPC, original data of GOES X-ray and Proton Flux, and ACE SolarWind Magnetic and Plasma Prameters.
Bartol NM Group Top Page
Bartol Spaceship Earth GLE Monitor, 1-minute real time plot of Spaceship Earth NM stations and a few other high-latitude NM stations.