Our goals :

1. Temperature effect of the muon component of cosmic ray and practical possibilities of its accounting Berkova M., Belov A., Smirnov D., Eroshenko E., Klepach E., Yanke V. Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation RAS (IZMIRAN), Moscow, Russia • Our goals: • To receive the hourly data of the muon telescopes without temperature effect for the whole period of observations. We use data from Nagoya telescope, Yakutsk telescope (sea level and 7 mwe), Yakutsk ionization chamber. • To examine the theoretical densitiesof the temperature coefficient by experiment. • To examine and prepare the experimental data for the next stage. First of all it’s definition of the spectral variations of the cosmic rays in a huge range of energy (1-100 GeV), and also the reconstruction of the altitudinal temperature profile of atmosphere according to various types of detectors with various thresholds of registration.

2. Data of TemperatureSounding There is another way to receive information about the altitudinal distribution of temperaturebesides atmosphere sounding nearby the muon telescope point. As to global data radio-scan , optical, acoustic and radar-tracking sounding give only 15 % of information about analtitudinal behavior of atmosphere temperature, leaving almost uncoveringlarge oceanic, subpolar and mountain areas; one can capture these areas only by the satellite’s measuring. In meteorology models which allow to receive analtitudinal behavior of temperature in atmosphere in any point and at any moment are built on the basis of the generalised data. We obtained the data of altitudinal sounding for the standard isobaric levels at our points of interest. The one model’s results are available in electronic publishing (NOAA, 2008). Comparison of temperature distribution in atmosphere at the moment 1999-01-0100:00 for Moscow region according to the NOAA model(red triangles) and experimental data (black circles).

3. Data of TemperatureSounding Comparison of temperature distribution in atmosphere for Moscow region according to the NOAA model(red triangles) and experimental data (black circles).

4. Data of TemperatureSounding Unfortunately such models aren’t supported in real time but they are available with short delay in some years for retrospective analysis. We use just the same data. The data accuracy depending on isobaric level apparently is a few degrees (for example around Moscow region). We obtained the data of altitudinal sounding for the standard isobaric levels at our points of interest. See the table:

5. Density of the temperature coefficient (differential temperature coefficients)

6. Nagoya Muon Telescope

7. Nagoya Muon Telescope

8. Nagoya Muon Telescope

9. Nagoya Muon Telescope

10. Data of TemperatureSounding. Extrapolation. Temperature time changes for three levels: 200, 500 и 1013 mb. Model monthly average data – black curves, extrapolated data – grey curves, the mid-annual temperature – red lines. Root-mean-square deviations of model temperature values from averages for three isobaric levels: 200, 500 и 1013 mb.

11. Yakutsk ionization chamber

12. Yakutsk ionization chamber

13. Yakutsk ionization chamber The problem is – we use density of the temperature coefficient which is closer to corresponding function for 7 mwe (0°) but not for WT(45°). May be ceiling?

14. Yakutsk Muon Telescope (sea level) Primary data of Yakutsk telescope and the data after their verification.

15. Yakutsk Muon Telescope (sea level)

16. Yakutsk Muon Telescope (7 mwe) Primary data of Yakutsk telescope and the data after their verification.

17. Yakutsk Muon Telescope (7 mwe)

18. The second stage.Definition of the spectral variations of the cosmic rays in a huge range of energy (1-100 GeV), and reconstruction of the altitudinal temperature profile of atmosphere according to various types of detectors.

19. Summary 1) Completeness and accuracy of the data ofaltitudinal atmosphere temperature profile received on the basis of the model (NOAA, 2008) is satisfactory enough for the muon telescopes correction for the temperature effect for intervalsfrom monthly average to hourly average . 2) Comparison of the muon component data of the Nagoya scintillation telescope, corrected forthe temperature effect, with the data of other detectors (neutron monitors) has proved experimentally the correctness of the used densitiesof temperature coefficients for all directions. It is nesessary to improve the densities of temperature coefficients for Yakutsk detectors with taking into account a thickness of the screen over the detector and other parametres. 3) The hourly, dailyand monthly average data correctedforthe temperature effect over all supervision period are received and accessible to the address: ftp://cr0.izmiran.rssi.ru/COSRAY!/FTP_MUON/

20. Literature • Belov A.V., Dorman L.I., Gushchina R.T., Yanke V.G., “Temporal and latitude dependence of the temperature effect for neutron component of cosmic rays”. Proc. 24-th Intern. • Cosmic Ray Conf., Rome, Vol. 4, pp. 1141-1144, 1995d. • А.В.Белов, Р.Т.Гущина, В.Г.Янке. Температурный эффект нейтронной компоненты космических лучей. Геомагнетизм и аэрономия, т.37. N2.с.100, 1997. • NOAA, http://ideas.ngdc.noaa.gov/ideas or http://clust1.wdcb.ru/ideas(требуется установка Java), 2007. • Nagashima K., Fuji Z., Sakakibara S., Fujimoto K., Ueno H. Report of cosmic ray research laboratory, N3, Nagoya, 1978. • Nagoya, Archive, 1976, http://www.stelab.nagoya-u.ac.jp/ste-www1\div3\muon\muon3.html • Nagoya, Real Time, 2007,ftp://stelab.nagoya-u.ac.jp/pub/cosmic.nagoya/nagoya/data_provisional • G.V. Shafer, Yu.G. Shafer. Precision observation of cosmic rays in Yakutsk. Novosibirsk: Nauka. 1984. 732p. (In Russian). • Кузмин А.И., “Вариации космических лучей и солнечная активность”, Москва, Наука, 1968. • Дорман Л.И., Янке В.Г., “К теории метеорологических эффектов космических лучей”, Изв.Ан СССР, серия физическая, т. 35, No 12, 2556, 1971.