CRD Active in Solar Weather Research
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PhD student Nerses Gevorgian (seated) and Prof. Chilingaryan
are looking over the data from the recent Solar eruption of April 15,
2001 gathered with the Aragats monitors.
Dr. Gagig Gharagyozyan (back) is checking to make sure that all the monitoring systems are functioning.
The Cosmic Ray Division (CRD) of the Yerevan Physics Institute is actively engaged in a number of astrophysical and related areas of research. The CRD operates two cosmic ray monitoring stations on Mt. Aragats in Armenia. Cosmic ray and solar data is gathered at these two stations and sent by microwave relay to CRD's facilities in Yerevan. In Yerevan the data is analysed using sophisticated computer algorithms developed by the CRD. The latest data is also posted on CRD's Internet site every 3 minutes.
One of CRD's major research activities is the forecasting and monitoring of geomagnetic and radiation storms caused by violent eruptions on the sun. Such events can damage satellites and endanger astronauts in space, disrupt power systems on earth and interfere with communications. There is evidence as well that solar radiation storms may endanger the health of passengers and crew members in flights over polar regions. Thus, the ability to forecast the effects of these storms on the earth is of great importance.
The following press release from the CRD addresses the advantages and disadvantages of space based and ground based monitoring systems. Space agencies, such as NASA, operate space based monitoring system which monitor solar data from satellites. Other researchers, including the Cosmic Ray Division, operate ground based systems. Both types of monitoring systems have advantages and disadvantages. The Cosmic Ray Division, in its press release, makes a point that combining data from both space based and ground based systems results in more accurate and timely predictions than can be made using data from either type of system alone.
Support Committee for Armenia's Cosmic Ray Division
PO Box 566
Harvard, MA 01451
CRD IN ARMENIA: "EARLY WARNING SYSTEM CAN SIGNIFICANTLY INCREASE SATELLITE FLEET SECURITY"
"Large area ground-based detector networks can enhance the accuracy and efficiency of harmful solar radiation storm predictions by complementing data available from space borne detectors," say scientists from the Cosmic Ray Division (CRD) of the Yerevan Physics Institute in Armenia.
An increasingly large number of mission-critical activities dependent on the flawless functioning of high-technology systems include satellites. Yet, Solar radiation storms caused by violent explosions on the Sun can unleash intense fluxes of charged particles which often adversely affect the normal functioning of satellites by disrupting space-borne electronics and endangering space station crews. As much as 50% of the total energy from such solar events emerges as electrons and atomic nuclei, often travelling in the direction of the Earth. Depending on their energy, these particles can reach the earth within 10 minutes to several hours after explosions on the sun. Such radiation storms occur most frequently after a year of maximum of solar activity, which we entered this past year.
Currently there are two different approaches to monitoring and forecasting the severity and impact of imminent solar radiation storms. A space-based approach is championed by NASA, and uses space-borne detectors. The Cosmic Ray Division of Yerevan Physics Institute, in Armenia, champions a ground-based approach using large arrays of detectors.
These two systems are complementary, and there are certain advantages to each. Space-based detectors in earth orbit can measure effects of the sun's activity 24 hours per day. These space-based detectors can directly measure electromagnetic radiation from flares and fluxes of low energy solar particles with high precision. Unfortunately, high-intensity fluxes of particles often "blind" the satellite detectors by causing them to go into protective stand-by mode, thus making information from the detectors unavailable. It then becomes impossible to issue alerts. Because the space-based sensors detect the late arriving low-energy particles, the warning time to protect sensitive equipment is reduced.
Ground-based detectors, such as those on Mt. Aragats in the Republic of Armenia, can be very large and take advantage of an enhanced detection capability due to the secondary showers produced by high-energy particles traversing the earth's atmosphere. Thus they can detect the low fluxes of early-arriving high-energy solar particles as well as fluxes of the secondary particles (muons and electrons) generated by collisions of solar protons in the atmosphere. By correlating these fluxes with each other and with data from electromagnetic detectors on satellites, the reliability and the warning time of forecasts can be improved significantly. The disadvantage of ground-based systems is that events occurring at night when the sun is not visible may go unnoticed. This problem can be solved with a network of ground-based detectors circling the earth going from east to west such that there is 24-hour surveillance of potentially harmful solar events.
Thus, when the data from space-based detectors and ground-based detectors is combined, the accuracy of the predictions is enhanced over that of the individual systems alone. Making accurate predictions and minimizing false alarms is extremely important to the end user, because shutting down vulnerable systems in order to safeguard them can be costly. Minimizing false alarms is imperative.
The Cosmic Ray Division in Armenia has already verified the feasibility of making early and accurate predictions during this current highly active solar period. They continue to develop more efficient detection, data analysis and early warning methods and have a proposal with the International Science and Technology Center to further this research. If approved, the potential benefits from this project could save billions of dollars in protecting earth-orbiting satellites, ground-based power grids, flight equipment and personnel.
This service is partly supported by NATO NIG-975436 grant and ISTC A216 project.
June 28, 2001
Contacts: Ashot Chilingaryan, Nerses Gevorgyan, nerses@crdlx5.yerphi.am
Cosmic Ray Division, Yerevan Physics Institute, http://crdlx5.yerphi.am