3,797 research outputs found
Correlation between radio and broad-line emissions in radio-loud quasars
Radio emission is a good indicator of the jet power of radio-loud quasars,
while the emission in broad-line can well represent the accretion disc
radiation in quasars. We compile a sample of all sources of which the
broad-line fluxes are available from 1 Jy, S4 and S5 radio source catalogues. A
correlation between radio and broad-line emission for this sample of radio-loud
quasars is presented, which is in favour of a close link between the accretion
processes and the relativistic jets. The BL Lac objects seem to follow the
statistical behaviour of the quasars, but with fainter broad-line emission.Comment: 9 pages, accepted for publication in MNRA
Evidence for anisotropic motion of the clouds in broad-line regions of BL Lacertae objects
The masses of central massive black holes in BL Lac objects are estimated
from their host galaxy absolute magnitude at R-band by using the empirical
relation between absolute magnitude of host galaxy and black hole mass. Only a
small fraction of BL Lac objects exhibit weak broad-line emission, and we
derive the sizes of the broad-line regions (BLRs) in these BL Lac objects from
the widths of their broad emission lines on the assumption of the clouds being
virilized in BLRs. It is found that the sizes of the BLRs in these sources are
usually 2-3 orders of magnitude larger than that expected by the empirical
correlation between BLR size and optical luminosity defined by a sample of
Seyfert galaxies and quasars. We discuss a variety of possibilities and suggest
it may probably be attributed to anisotropic motion of the BLR clouds in these
BL Lac objects. If the BLR geometry of these sources is disk-like, the viewing
angles between the axis and the line of sight are in the range of 2-12 degrees,
which is consistent with the unification schemes.Comment: 5 pages, accepted for publication in Ap
Incarcerated Fathers’ Experiences in the Read to Your Child/Grandchild Program: Supporting Children’s Literacy, Learning, and Education
In response to rising parental incarceration, some correctional facilities and outside organizations offer family literacy programs for parents in prison. However, research on these correctional education initiatives is scant. This paper uses qualitative data to analyze how 11 fathers in a rural Pennsylvania prison were involved in their children’s literacy, learning, and education before and during incarceration and through the Read to Your Child/Grandchild (RYCG) program. Before RYCG, most fathers had taken steps such as reading to children, teaching reading and math, attending parent-teacher conferences, helping with homework, and singing and rhyming—and then sought to continue supporting their children’s learning from within prison. Fathers used RYCG materials (video-recorded book reading, children’s book, scrapbook) to emphasize the importance of education, literacies, and numeracy. They also created personalized scrapbooks that cultivated their children’s literate abilities and cognitive, academic, and socio-emotional development. This research contributes to the nascent literature on family literacy for incarcerated parents
Further Evidence that the Redshifts of AGN Galaxies May Contain Intrinsic Components
In the decreasing intrinsic redshift (DIR) model galaxies are assumed to be
born as compact objects that have been ejected with large intrinsic redshift
components, z_(i), out of the nuclei of mature AGN galaxies. As young AGN
(quasars) they are initially several magnitudes sub-luminous to mature galaxies
but their luminosity gradually increases over 10^8 yrs, as z_(i) decreases and
they evolve into mature AGN (Seyferts and radio galaxies). Evidence presented
here that low- and intermediate-redshift AGN are unquestionably sub-luminous to
radio galaxies is then strong support for this model and makes it likely that
the high-redshift AGN (quasars) are also sub-luminous, having simply been
pushed above the radio galaxies on a logz-m_(v) plot by the presence of a large
intrinsic component in their redshifts. An increase in luminosity below z =
0.06 is also seen. It is associated in the DIR model with an increase in
luminosity as the sources mature but, if real, is difficult to interpret in the
cosmological redshift (CR) model since at this low redshift it is unlikely to
be associated with a higher star formation rate or an increase in the material
used to build galaxies. Whether it might be possible in the CR model to explain
these results by selection effects is also examined.Comment: 12 pages, 2 figures. Contains response to referees suggestions.
(Accepted for ApJL
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