6 papers · 1 filter
The Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey II: The First Four Epochs
J. E. J. Lovell, B. J. Rickett, J-P. Macquart +8
We report on the variability of 443 flat spectrum, compact radio sources monitored using the VLA for 3 days in 4 epochs at ~ 4 month intervals at 5 GHz as part of the Micro-Arcseco…
Observations of Intrahour Variable Quasars: Scattering in our Galactic Neighbourhood
H. E. Bignall, D. L. Jauncey, J. E. J. Lovell +3
Interstellar scintillation (ISS) has been established as the cause of the random variations seen at centimetre wavelengths in many compact radio sources on timescales of a day or l…
MASIV:The Microarcsecond Scintillation-Induced Variability Survey
J. E. J. Lovell, D. L. Jauncey, C. Senkbeil +8
We are undertaking a large-scale 5 GHz VLA survey of the northern sky to search for rapid intra-day variability (IDV). Over four observing epochs we found that 56% of the sources s…
Spectral index of the H2O-maser emitting planetary nebula IRAS 17347-3139
J. F. Gomez, I. de Gregorio-Monsalvo, J. E. J. Lovell +5
We present radio continuum observations of the planetary nebula (PN) IRAS 17347-3139 (one of the only two known to harbour water maser emission), made to derive its spectral index…
HO maser emission from bright rimmed clouds in the northern hemisphere
R. Valdettaro, F. Palla, J. Brand +1
We report the results of a multi-epoch survey of water maser observations at 22.2 GHz with the Medicina radiotelescope from 44 bright rimmed clouds (BRCs) of the northern hemispher…
The Discovery of H2O Maser Emission in Seven AGN and at High Velocities in the Circinus Galaxy
L. J. Greenhill, P. T. Kondratko, J. E. J. Lovell +4
We report the discovery of H2O maser emission at 1.35 cm wavelength in seven active galactic nuclei (at distances up to <80 Mpc) during a survey conducted at the 70-m diameter ante…