Return-Path: Received: (qmail 6021 invoked from network); 25 Sep 2001 11:40:58 -0000 Received: from unknown (HELO warrior-inbound.services.quay.plus.net) (212.159.14.227) by excalibur.plus.net with SMTP; 25 Sep 2001 11:40:58 -0000 Received: (qmail 18371 invoked from network); 25 Sep 2001 11:08:35 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 25 Sep 2001 11:08:35 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 15lq01-0003Nv-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 25 Sep 2001 12:03:37 +0100 Received: from protactinium.btinternet.com ([194.73.73.176] helo=protactinium) by post.thorcom.com with esmtp (Exim 3.16 #2) id 15lq00-0003Nq-00 for rsgb_lf_group@blacksheep.org; Tue, 25 Sep 2001 12:03:36 +0100 Received: from [213.1.77.86] (helo=default) by protactinium with smtp (Exim 3.22 #6) id 15lpzM-0006fH-00 for rsgb_lf_group@blacksheep.org; Tue, 25 Sep 2001 12:02:57 +0100 Message-ID: <000701c145b1$23215700$564d01d5@default> From: "Alan Melia" To: "LF-Group" Subject: LF: X-ray flare enhancement Date: Tue, 25 Sep 2001 11:53:41 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 4.72.3110.5 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Hi all there was a large X-ray flare classed as an X3.0 at 1030z yesterday (Mon 24th). I now have the data from Brian's (CT1DRP) plot of DCF39 ( a path length of 1987 kms) for that period. This shows that there was about a 15dB peak enhancement to the average conditions at that time of day on the path from DCF39 to Porto. This would not be so evident where the ground wave signals are stronger than those produced by the ionospheric 'reflection', but it should have been evident at path distances in excess of about 700kms, for amateur signal strengths. The interesting thing is that the enhancement, over average daytime levels for the last two weeks, exceeded 10dB over a period of about 60 minutes, in other words a very usable 'lift' for inter EU contacts There are forecasts of the possibility of more flares in the M and X class from the same region, so if there are any OH, OM, S52, HA stations around It could pay to keep an eye on the NOAA site. This will give a real-time display of the the GOES satellite X-ray detectors, any levels over M1.0 can give useful enhancements. This is a daylight only effect and the enhancements seem best between about 09000z and about 1600z at this time of year. Thanks to Brian for a great bit of continuous data logging. Cheers de Alan G3NYK Alan.Melia@btinternet.com