Data are intended strictly for research/educational purposes and public non-commercial services.
In a case of commercial use, please contact the station manager

Users of the data are expected to acknowledge this web-site and the Sodankyla Geophysical Observatory.

Data from Dome C NM should be additionally acknowledged as obtained due to support of the French-Italian Concordia Station (IPEV program n903 and PNRA Project LTCPAA PNRA14_00091).



data resolution

on-line requests *
since 1996 
1 min
on-line requests *
since 1968
5 min
on-line requests *
 since 1964
1 hour 
file list
 GLE data
GLE format (300 sec) 
e-mail request (
10 sec 
* Data for the current month are not verified.

List of dates with missed/reconstructed data

Barometric correction

The standard pressure Po of the is 1000 mb for OULU NM, and 650 mb for DOMC/DOMB. The barometric coefficients k are -0.74%/mb for OULU, -0.769 %/mb for DOMC, -0.754 %/mb for DOMB . The corrected count rate is
I corr  =  I uncorr *exp(k*(Po-P)/100).

DOMC/DOMB are also subject to a slight correction for the indoor temperature.

Efficiency Correction factor

Because of the changes of hardware/software during the station operation period, the efficiency of cosmic ray registration might have been slightly changing. This is carefully taken into account, and the efficiency correction factor is used to provide a homogenous long-term data series.

The NM count rate in the database is normalized to the count rate before 1985 so that
I normalised  =  I measured  * FC

where FC is the efficiency correction factor (see below).
01/1964 - 30/09/1985
01/10/1985 - 31/12/1994
New automatic digital barometer
01/01/1995 - 31/12/1999
New data collecting system
01/01/2000 - 31/05/2003  
replacement of section A high voltage system
01/06/2003 - 31/07/2008;
adjustment of section A high voltage system
01/08/2008 - 31/10/2009;
New data registration system
since 01/11/2009 ;
Change of the station environment (Muon detector is installed)

For any kind of comments/questions/requests please contact Ilya Usoskin via e-mail

Back to the main page 

Last modified 15.12.2016 by Ilya Usoskin