Tuesday, 13 November 2012

Science Tuesday: Recent Papers

Tuesday is the science day on the EISCAT_3D blog. For the science feature, you can submit your research to the blog with an image, photo, or graph, and a short text explaining the study and the key result. We will then publish your work here. For the time being, please send any input to the blog's editor Thomas Ulich (thu -at- sgo -dot- fi). Thanks!
  • High-precision measurement of satellite velocity using the EISCAT radar, by T. Nygrén, J. Markkanen, A. Aikio, and M. Voiculescu, ANGEO, 2012, Vol.30, pp. 1555-1565, SRef-ID: 1432-0576/angeo/2012-30-1555, http://direct.sref.org/1432-0576/angeo/2012-30-1555.
  • The pulsed nature of the nightside contribution to polar cap convection: repetitive substorm activity under steady interplanetary driving, by P. E. Sandholt, Y. L. Andalsvik, and C. J. Farrugia, ANGEO, 2012, Vol.30, pp. 1539-1553, SRef-ID: 1432-0576/angeo/2012-30-1539, http://direct.sref.org/1432-0576/angeo/2012-30-1539.
  • Anisotropic pitch angle distribution of ~100 keV microburst electrons in the loss cone: measurements from STSAT-1, by J. J. Lee, G. K. Parks, E. Lee, B. T. Tsurutani, J. Hwang, K. S. Cho, K.-H. Kim, Y. D. Park, K. W. Min, and M. P. McCarthy, ANGEO, 2012, Vol.30, pp. 1567-1573, SRef-ID: 1432-0576/angeo/2012-30-1567, http://direct.sref.org/1432-0576/angeo/2012-30-1567.
Source: COSIS.net Alert Service Subscriptions.

Wednesday, 7 November 2012

EISCAT Peer-Review Programme: Radar Time Available for Anyone Now

EISCAT Scientific Association invites applications for observing time on the EISCAT facilities in 2013, by individual scientists, research groups, and consortia throughout the world on equal, competitive basis. This means that anyone can apply, independent of whether or not the applicant is from an EISCAT associate country.

While evaluations are merit based, in the case of two applications having similar merits in evaluation, preference will be given either to those applicants who are new to the EISCAT facilities, in order to enlarge the EISCAT user community and further more open access to the facilities, or to the applicant showing stronger educational impact in their proposal.

EISCAT is aiming to establish closer ties with the users of incoherent scatter radars (ISR) worldwide and bring in new users, young scientists, postdocs, and students who have not used the EISCAT facilities in the past.  The EISCAT International Symposium, which will take place 12th to 16th August 2013, will also aim to reach similar goals of bringing ISR users from around the world to interact more closely and collaborate.

The present call is the first call for 2013. In total, 200 hours of experiment time are open for international, peer-reviewed competition, and are available for the use of any of the current EISCAT facilities.

Please refer to EISCAT's pages on the Peer-Review Programme and in particular to the definition of the call for more information.

The deadline for proposals is 15th November 2012 at 24:00 UTC.

Tuesday, 6 November 2012

Science Tuesday: Recent Papers

Tuesday is the science day on the EISCAT_3D blog. For the science feature, you can submit your research to the blog with an image, photo, or graph, and a short text explaining the study and the key result. We will then publish your work here. For the time being, please send any input to the blog's editor Thomas Ulich (thu -at- sgo -dot- fi). Thanks!
  • Large mesospheric inversion layer due to breaking of small-scale gravity waves: Evidence from Rayleigh lidar observations over Gadanki (13.5°N, 79.2°E), by K. Ramesh, S. Sridharan, J. Atm. Sol.-Terr. Phys., 89, 90-97, 2012, (link).
  • Solar forcing on the ice winter severity index in the western Baltic region, by M.C. Leal-Silva, V.M. Velasco Herrera, J. Atm. Sol.-Terr. Phys., 89, 98-109, 2012, (link).
  • Generation of zonal flow and magnetic field by coupled internal-gravity and Alfvén waves in the ionospheric E-layer, by T.D. Kaladze, L.Z. Kahlon, L.V. Tsamalashvili, D.T. Kaladze, J. Atm. Sol.-Terr. Phys., 89, 110-119, 2012, (link).
  • Local climatological modeling of ionospheric irregularities detected by GPS in the mid-latitude region, by G. Wautelet, R. Warnant, J. Atm. Sol.-Terr. Phys., 89, 132-143, 2012, (link).
  • Climatology of the inter-hemispheric field-aligned currents system over the Nigeria ionosphere, by O.S. Bolaji, A.B. Rabiu, E.O. Oyeyemi, K. Yumoto, J. Atm. Sol.-Terr. Phys., 89, 144-153, 2012, (link).
Source: ScienceDirect Message Center.

Friday, 2 November 2012

First Light: Tri-Static VHF Radar

On 1st November 2012, EISCAT carried out the first tri-static experiment with the VHF transmitter in Tromsø and the remote dishes in Kiruna and Sodankylä, which had been converted to the VHF frequency of 224 MHz earlier this autumn. Good signals were immediately seen at all sites, with Signal-to-Noise Ratios (SNR) exceeding 10%.

VHF Reception at Tromsø.
The monostatic part of this experiment was a test run low-elevation Common-Program runs with extra long ranges to be carried out in December, but during this particular test experiment the antenna was pointed vertically. The beams from the remote 32-m dish antennas in Kiruna and Sodankylä intersected the transmitter beam at the F-region peak at 270 km. The transmitter sent a circular polarised signal at 223.6 MHz.

VHF at Kiruna, Sweden (left) and Sodankylä, Finland (right).
However, in this test, the remote sites received signals only in horizontal polarisation, which is currently the only polarisation, which has a calibration noise source connected. It will take a couple of months to finalise the project with fully calibrated signal together with a software polariser in order to take into account the Faraday rotation, which the signal gets on the way from the scattering volume to the remote antennas.

With these fantastic first results we wish all of you a very good weekend!

Text and images: Adapted from Ingemar Häggström.