From: Dr. Lex Wennmacher [wennmach@geo.Uni-Koeln.DE]
Sent: Wednesday, August 05, 2009 2:05 PM
To: Bourouaine, Sofiane
Cc: Marsch Prof., Eckart; Prof. F. M. Neubauer
Subject: Re: Helios Magnetfelddaten

Dear Dr. Bourouaine,

you may download the Helios data using the following URLs:

https://data.geomet.uni-koeln.de/ad530/helios1-ascii.tar.gz
https://data.geomet.uni-koeln.de/ad530/helios2-ascii.tar.gz

Please authenticate with
Username: ad530
Password: soileh

The first file is a compressed tar archive of the high resolution Helios 1 data. The data is organized in files for each day. The second file contains the high resolution Helios 2 data.

The daily files are in ASCII format and contain the following columns: The first column is the UTC time in ISO8601 format, the second is B_x, the third is B_y, and the fourth is B_z, all in nT, like so:


Time in ISO 8601 format      Bx[nT]        By[nT]         Bz[nT] 
----------------------------------------------------------------
1975-02-19T00:51:15.141      2.200         -7.100         -7.500
1975-02-19T00:52:19.141      1.500         -5.700         -8.300
          .                    .              .              . 
          .                    .              .              .  
          .                    .              .              .  


The two files he1_resolution.list and he2_resolution.list (attached) provide you an overview of resolutions available in the data daily files.


ATTENTION:
The coordinate system is HSE for Helios 1, but since the spin axis of Helios 2 was opposite to that of Helios 1 (and the sun), the principal coordinate axes for Helios 2 are (x_HSE, -y_HSE, -z_HSE). I. e. you'll have to change the sign of B_y and B_z in order to obtain B in HSE.


Let me know in case you encounter problems.


Best regards
Lex Wennmacher

--
Dr. Alexandre Wennmacher
Institut fuer Geophysik und Meteorologie         wennmach@geo.Uni-Koeln.DE
Universitaet zu Koeln                            phone  +49 221 470 - 3387
D-50923 Koeln                                    fax    +49 221 470 - 5198

On Wed, Aug 05, 2009 at 10:23:26AM +0200, Marsch Prof., Eckart wrote:
> Lieber Herr Dr. Wennmacher,
> 
> darf ich mich (wie per email mit Prof. Neubauer abgesprochen) an Sie 
> wenden mit der Bitte, mir und Herrn Dr. Sofiane Bourouaine hier am MPS 
> die Helios hochaufgelösten Magnetfelddaten zugänglich zu machen. 
> Vielen Dank im voraus für Ihre Hilfe.
> 
> Beste Grüße,
> Eckart Marsch
> 
> ________________________________
> 
>   Prof. Dr. E. Marsch
>   Max Planck Institute for 
>   Solar System Research
>   Max-Planck-Straße 2
>   37191 Katlenburg-Lindau
>   Germany
>   Tel.: 49 (0)5556 979 292
>   Fax : 49 (0)5556 979 240
>   e-mail: marsch@mps.mpg.de
>