If the total energy of a radio flare is known, one can estimate the mass accretion rate of the disk by assuming equipartition of magnetic energy and the gravitational potential energy of accreting matter. We present here an example of how such an estimate could be done. Our recent radio observation using the Giant Meter Radio Telescope (GMRT) of the galactic black hole transient A0620-00 at 1.2...

The long-term variability of the multiwavelength blazar emission can be interpreted in terms of orientation variations of a helical, inhomogeneous, non-thermally emitting jet, possibly caused by the orbital motion of the parent black hole in a binary system (Villata & Raiteri 1999). The helical-jet model is here applied to explain the quasi-periodic radio-optical light curves and the broad-band...

A Radio-Frequency-Identification (RFID) tag is a small and cheap device which is combined in IC chip and an antenna for radio communications. It emits an ID in response to a query from a radio communication device called as a reader. For this reason, the RFID tag is used for management of goods and it is used as a substitute for a bar code. However, RFID system may infringe on a consumer's priv...

The radio-loud quasar CTD 135 (2234+282, J2236+2828) has been proposed as a candidate compact symmetric object (CSO), based on its radio structure revealed by multi-frequency very long baseline interferometry (VLBI) imaging observations milliarcsec angular scales. CSOs are known young jetted active galactic nuclei (AGN) whose relativistic plasma jets misaligned with respect to the line of sight...

We analyze the computational costs of searches for continuous monochromatic gravitational waves emitted by rotating neutron stars orbiting a companion object. As a function of the relevant orbital parameters, we address the computational load involved in targeted searches, where the position of the source is known; the results are applied to known binary radio pulsars and Sco-X1.

It is revealed that the unique properties of ultrathin metasurface resonators can improve magnetic resonance imaging dramatically. A metasurface formed when an array of metallic wires is placed inside a scanner under the studied object and a substantial enhancement of the radio-frequency magnetic field is achieved by means of subwavelength manipulation with the metasurface, also allowing improv...

In this letter we present the results of a wavelet analysis of the radio light curve of the BLLac Object PKSB0048−097 from the University of Michigan Radio Astronomy Observatory monitoring program at 8GHz during twenty-five years, from 1979 to 2004. The results show a remarkable periodicity of 450–470 days in the early 1980s that changed to a ∼585 day periodicity in the late 1980s to early 1990...

We report the first detection of a water megamaser in a radio-loud galaxy, 3C 403. This object has been observed as part of a small sample of FR IIs with evidence of nuclear obscuration. The isotropic luminosity of the maser is ∼1200 L . With a recessional velocity of cz∼ 17680 kms−1 it is the most distant H2O maser so far reported. The line arises from the densest interstellar gas component ev...

We present 8.4 GHz VLA A-array and 1.4 GHz VLBA results on the radio continuum emission from the highest redshift radio-loud quasar known to date, the z = 6.12 QSO J1427+3312. The VLA observations show an unresolved steep spectrum source with a flux density of 250 ± 20 μJy at 8.4 GHz and a spectral index value of α 1.4 = −1.1. The 1.4 GHz VLBA images reveal several continuum components with a t...

Context. Gigahertz Peaked Spectrum (GPS) radio galaxies are generally thought to be the young counterparts of classical extended radio sources. Statistically complete samples of GPS sources are vital for studying the early evolution of radio-loud AGN and the trigger of their nuclear activity. The ‘Parkes half-Jansky’ sample of GPS radio galaxies is such a sample, representing the southern count...