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The Low-Mass End of the MBH/Mhost Relation in Quasars

Uslenghi, Michela; Decarli, Roberto; Treves, Aldo +3 more

The Mbh-Mhost relation in quasars has been probed only in a limited parameter space, namely at Mbh~10^9 Msun and Mhost~10^12 Msun. Here we present a study of 26 quasars lying in the low-mass end of the relation, down to Mbh~10^7 Msun. We selected quasars from the SDSS and HST-FOS archives, requiring modest Mbh (as derived through the virial paradi…

M94 as a Unique Testbed for Black Hole Mass Estimates and AGN Activity at Low Luminosities

Seth, Anil C.; Constantin, Anca

We discuss the peculiar nature of the nucleus of M94 (NGC 4736) in the context of new measurements of the broad H_alpha emission from HST-STIS observations. We show that this component is unambiguously associated with the high-resolution X-ray, radio, and variable UV sources detected at the optical nucleus of this galaxy. These multi-wavelength ob…

Preliminary Results on Irradiance Measurements from Lyra and Swap

Berghmans, D.; Kariyappa, R.; Damé, L. +5 more

Rapid Disappearance of Penumbra-Like Features near a Flaring Polarity Inversion Line: The Hinode Observations

Gosain, Sanjay; Ravindra, B.

We present the observations of penumbra like features (PLFs) near a polarity inversion line (PIL) of flaring region. The PIL is located at the moat boundary of active region (NOAA 10960). The PLFs appear similar to sunspot penumbrae in morphology but occupy small area, about 6$\times10^{7}$ km$^{2}$, and are not associated with sunspot or pore. We…

Pulsar-Driven Jets in Supernovae, Gamma-Ray Bursts, and the Universe

Middleditch, John

The bipolarity of Supernova 1987A can be understood through its very early light curve observed from the CTIO 0.4-m telescope and IUE FES, and following speckle observations of the `Mystery Spot' by two groups. These indicate a highly directional beam/jet of light/particles, with initial collimation factors in excess of 10,000 and velocities in ex…