Welcome to the MRT home page

Please note that this page is under construction so many of the links may not exist.

The MRT. is a joint project of the

Indian Institute of Astrophysics

and the

Raman Research Institute

The project was started by Prof. Ch.V. Sastry of IIA. The overall head of the MRT project is Prof. N. Uday Shankar of RRI. The present head of MRT in Mauritius is Dr G K Beeharry.

Some pictures of our telescope site are here

Our newest and most exciting result is here

The MRT specifications are as follows:

Location: Bras d'Eau, N E Mauritius. Latitude: 20^oS. Longitude: 60^oE.
Observing frequency: 151.6MHz
Telescope configuration: T-shaped 2048 m E-W arm and 880 m N-S arm.
Basic element: Helical antenna.
Polarization: Right Circular.
HPBW of helix: 60^o x 60^o.
Instrument zenith Declination: -40^o.
Declination coverage: -70^o to -10^o.
Collecting area of helix: 4 m² at 150 MHz.
East-West arm: 32 groups with 32 helices each.
North-South arm: 15 mobile trolleys each with 4 helices.
1st IF frequency: 30 MHz.
2st IF frequency: 10.1 MHz.
Instrumenatl bandwidths: 0.15, 1.0, 1.5, 3.0 MHz.
Digitization before correlation: 2-bit 3-level.
Correlation receiver: 32 x 16 complex channels.
No of baselines measured per day: 32 x 16.
Minimum and maximum baselines: 0, 1024 lambdas.
Time to get all spatial frequencies (baselines): 63 days.
Synthesized beam-width: 4' x 4.6'sec(dec. + 20.1388^o.
Point source sensitivity for the survey: 200 mJy (3 sigma).

The MRT is a 2km x 1km T-shaped aperture synthesis array. The 2km EW arm has 1024 fixed 2m helical antennae. The 1km NS arm has 64 antennae on 16 moveable trolleys. In the EW and NS arms the signals from 4 adjacent elements are phase equalised and combined. In turn, in the E-W arm after filtering and amplification, 8 such outputs are phase equalised and combined to produce a single section output. There are 32 of these sections. Because of the non-uniformity of the terrain the EW sections are at a number of different levels. After further processing these 32 channels and the 16 NS channels are correlated using a 1024 channel correlator receiver from the former Clark Lake array. Bandwidth decorrelation limits the sky coverage to ~10^o. To cover the complete beam of 60^o there is need to introduce delays. To this end a recirculator system is used which stores the astronomical data and reprocesses it through the correlators each time with a different delay. The Data Acquisition System interfaces the correlator to a PC. Its storage data format is compatible for transferring data to a set of workstations for further processing. For this we use PCs running the superb Linux O/S. (Faster local link to a Linux home page). We have been rescued in term of computing power by those wonderful people supplying the Linux distrubution.

General Objectives

Contributions to the field of Astronomy and Astrophysics.
Generate hitherto original data on the Southern Sky that will help in the understanding of solar, planetary, galactic and extragalactic astronomy.
Human Resource development.
Generate public interest in astronomy.

Scientific Objectives

To make radio images of the southern sky at 151.6 MHz with a point source sensitivity of 200 mJy.
To make astrophysical interpretation of radio images.
To produce a point source catalogue (equivalent to the Cambridge 6C survey) for the Declination range from -70^o to -10^o and study their spectra.
To observe pulsars and study their profiles.
To study the Galactic plane.
To observe and study the solar radio emission.
To study extended extragalactic radio sources.
To study Supernova Remnants.
To study steep spectrum sources.
We hope to discover new things, may be some new low-surface brightness radio sources like relics or some ultra-steep spectrum sources.
To develop local manpower in the field of Astrophysics, Electronics, Signal processing Algorithms, Computer Engineering and in related areas. So far, more than 50 undergraduate students in physics and engineering have been trained at MRT and nearly 25 have done their undergraduate projects related to MRT.

The Team

Nalini Issur (UoM)

Radhakhrishna (Dinesh) Somanah (uom)

Kumar Golap (uom)

Richard Guy Dodson (Durham University)

Sandeep Sachdev (Raman Research Institute)

Udaya Shankar (Raman Research Institute )

Girish K Beeharry UoM

Nadeem Oozeer (Ph.D student at the UoM)

Jayssen Ramanah (Ph.D. student at the UoM)

Things being done

We are collecting data for the full survey but there are different regions which are being imaged with different resolutions. E.g. a low resolution map of part of the galactic plane . See the individual pages of the members to get more info of what is being done

What has been done in the past

Here are some images that others have done. The GEETEE survey done in RRI by Uday and Dwaka. Ref K.S. Dwarakanath and N. Udaya Shankar 1990, J. Astrophys. Astr., 11 323. (fits file version here )

The 408 MHz survey done by lots of people. Ref Haslam et al, 1982, A and AS 47, 1.

If you want more you should look to the NASA page SkyView

For detailed information, expressions of support or anything else , please send e-mail to mrt@uom.ac.mu