G.N. Rajasekhara Girish Kumar Beeharry Mauritius Radio Telescope
description
Transcript of G.N. Rajasekhara Girish Kumar Beeharry Mauritius Radio Telescope
G.N. RajasekharaGirish Kumar Beeharry
Mauritius Radio Telescope
The CALLISTO spectrographin Mauritius
Outline
· First Antenna· Back end· Commissioning· First flare· Subsequent flares· Observations from other CALLISTOs· Future work
The First Antenna
Broad band logarithmic periodicantenna at MRT site.The antenna was built out ofstandard aluminum profiles in thelocal workshop.Frequency range goes from 20MHz up to 860 MHz in fixedvertical positionVertical tubes on both sides are made of PVC to mechanically support long, heavy dipoles..
The Back End
The CALLISTOspectrometer is on the left side of the table(below ‘TobleroneChocolate bar), powersupplies just behindand monitor withkeyboard and PC on the right.,
Commissioning (27.04,2009)
X-axis shows time expressed in UT, Y-axis frequency in MHz and Z-axis denotes the stored digital value of the ADC(without any calibration).The frequency resolution is ~ 4 MHz and time resolution is 250 msec (4 sweeps Per second).Data is stored in 15 min FITS files
Quiet Sun: with background (08-10-2009)
45 MHz
860MHz
15 minute time interval (UT)
Quiet Sun: background subtracted(08-10-2009)
45 MHz
860MHz
15 minute time interval (UT)
Active sun having sunspots: with background (24-09-2009)
45 MHz
860MHz
15 minute time interval (UT)
Active sun having sunspots: with background subtraction (24-09-2009)
45 MHz
860MHz
15 minute time interval (UT)
Zoom in Active sun having sunspots: with bkgrnd subtraction (24-09-2009)
45 MHz
860MHz
15 minute time interval (UT)
“First light” flarZoom in Active sun having sunspots: with bkgrnd s092009)e ( 2009)
Mauritius
45 MHz
860MHz
15 minute time interval (UT)
45 MHz
860MHz
15 minute time interval (UT)
“First light”close up May 1st 2009Mauritius
Solar flare (6th May 2009)Mauritius
45 MHz
860MHz
15 minute time interval (UT)
Solar flare (8th May 2009)
Mauritius
45 MHz
860MHz
15 minute time interval (UT)
Zoom in Solar flare (8th May 2009)
Mauritius
45 MHz
860MHz
15 minute time interval (UT)
Solar flare (8th May 2009) other stations
Bleien Humain
Solar flare (8th May 2009) other stations
Kasi Mauritius
Solar flare (8th May 2009) other stations
Ooty lin pol1: Lightning flash at 08:09:01.5 UT
Ooty lin pol 2:Lightning flash at 08:09:04 UT
Zoom in Solar flare (24th Sep 2009)
Mauritius
45 MHz
860MHz
15 minute time interval (UT)
Future Work
Antenna array: improved gain & sky coverage Calibration Timing experiments - Software development
Excellent first instrument for radio astronomy: Interested?