This plot displays the last Neutron Monitor counts in relative scale. It is produced with the NEST interface to NMDB data.
The plot is updated every 5 minutes (reload the page to update display if necessary). see also NMDB online access tools.
Please note that the real-time data shown here has not been checked by a human, so the data may contain measurement errors that can create “spikes” or “steps” in the data, see Checking neutron monitor data.
As some of the instruments are 50 years old and are operated in harsh conditions, it is not unsual to see errors like this. When these errors “disappear” this is because the data has been checked by a human and the measurements errors have been corrected. This is not done to “hide” anything but only to provide scientific valid data. All the spikes are still present in the database as ORI data (select Original in NMDB tables). By looking at the ASCII output, you can notice that the largest spikes are typically very short, while Ground-Level-Enhancements take several minutes to build up. Please check the Public Outreach section for further explanations about Cosmic Rays and how Neutron Monitors measure them.
PS Neutron Montitors do not measure neutrinos.
PPS Neutron Monitors rarely measure neutrons hitting the atmosphere as they have a very short life-time, only a few solar-neutron events have been identified so far. The neutrons that gave the name to the monitor are only produced inside the Neutron Monitor by secondary particles that are created in the atmosphere, which are in turn created by incoming high-energy particles (99% protons) at the top of the atmosphere.
If you have questions on how to analyse this data, please Contact Us.