219 research outputs found
Long-term variability of the optical spectra of NGC 4151: II. Evolution of the broad Ha and Hb emission-line profiles
Results of the long-term (11 years, from 1996 to 2006) H and H
line variations of the active galactic nucleus of NGC 4151 are presented. High
quality spectra (S/N>50 and R~8A) of H and H were investigated.
We analyzed line profile variations during monitoring period. Comparing the
line profiles of H and H, we studied different details (bumps,
absorption features) in the line profiles. The variations of the different
H and H line profile segments have been investigated. Also, we
analyzed the Balmer decrement for whole line and for line segments. We found
that the line profiles were strongly changing during the monitoring period,
showing blue and red asymmetries. This indicates a complex BLR geometry of NGC
4151 with, at least, three kinematically distinct regions: one that contributes
to the blue line wing, one to the line core and one to the red line wing. Such
variation can be caused by an accelerating outflow starting very close to the
black hole, where the red part may come from the region {closer to the black
hole than the blue part, which is coming} from the region having the highest
outflow velocities. Taking into account the fact that the BLR of NGC 4151 has a
complex geometry (probably affected by an outflow) and that a portion of the
broad line emission seems to have not a pure photoionization origin, one can
ask the question whether the study of the BLR by reverberation mapping may be
valid in the case of this galaxy.Comment: 24 pages, 18 figures, accepted for publications in A&
Spectral optical monitoring of the double peaked emission line AGN Arp 102B: II. Variability of the broad line properties
We investigate a long-term (26 years, from 1987 to 2013) variability in the
broad spectral line properties of the radio galaxy Arp 102B, an active galaxy
with broad double-peaked emission lines. We use observations presented in Paper
I (Shapovalova et al. 2013) in the period from 1987 to 2011, and a new set of
observations performed in 2012--2013. To explore the BLR geometry, and clarify
some contradictions about the nature of the BLR in Arp 102B we explore
variations in the H and H line parameters during the monitored
period. We fit the broad lines with three broad Gaussian functions finding the
positions and intensities of the blue and red peaks in H and H.
Additionally we fit averaged line profiles with the disc model. We find that
the broad line profiles are double-peaked and have not been changed
significantly in shapes, beside an additional small peak that, from time to
time can be seen in the blue part of the H line. The positions of the
blue and red peaks { have not changed significantly during the monitored
period. The H line is broader than H line in the monitored
period. The disc model is able to reproduce the H and H broad
line profiles, however, observed variability in the line parameters are not in
a good agreement with the emission disc hypothesis. It seems that the BLR of
Arp 102B has a disc-like geometry, but the role of an outflow can also play an
important role in observed variation of the broad line properties.Comment: 17 pages, Accepted for publication in A&
Vivencia del amamantamiento por madres adolescentes
A amamentação é um ato de grande importância e benefÃcio para a mãe e o filho e não há contra indicação para mães-adolescentes. O objetivo desta pesquisa é descrever a vivência da amamentação na adolescência e observar a ocorrência de desmame precoce. Trata-se de estudo qualitativo de abordagem descritiva, utilizando a técnica de grupo focal, realizada em um Centro de Saúde de uma Região Administrativa do Distrito Federal no ano de 2008. Os resultados obtidos revelaram que não está ocorrendo o desmame precoce no universo estudado e que existe uma boa vivência por parte das adolescentes em relação ao processo da amamentação. No entanto, percebe-se a necessidade de criação de grupos de apoio à s gestantes e à s puér peras adolescentes, sendo de responsabilidade, principalmente, do enfermeiro, a educação e a promoção do aleitamento materno. ______________________________________________________________________________________ ABSTRACTBreastfeeding is an act of great importance and benefit to both mother and child, and there is no contra indication for adolescent mothers. The aim of this research is to describe the experience of breastfeeding during adolescence and observe the occurrence of early weaning. This is a qualitative study with a descriptive approach, using the technique of focus group, held in a Health Center of an Administrative Region of the Distrito Federal, Brazil, in the year2008. The results revealed that early weaning does not occur among the studied group and that there is a good experience of adolescents in relation to the process of breastfeeding. However on realize the necessity of creating support groups for pregnant women and adolescent mothers, being the responsibility mainly of the nursing team. ______________________________________________________________________________________ RESUMENEl amamantamiento es un acto de gran importancia y beneficio para la madre y el niño y no hay contraindicaciónpara las madres-adolescentes. El objetivo de esta investigación es describir la experiencia del amamantamiento en laadolescencia y observar la ocurrencia de destete precoz. Se trata de un estudio cualitativo de abordaje descriptivo,utilizando la técnica de grupo focal, realizada en un Centro de Salud de una Región Administrativa del Distrito Federal enel año 2008. Los resultados obtenidos revelaron que no está ocurriendo el destete precoz en el universo estudiado y queexiste una buena experiencia por parte de los adolescentes en relación al proceso del amamantamiento. Sin embargo, senota la necesidad de creación de grupos de apoyo a las embarazadas y a las parturientas adolescentes, siendo deresponsabilidad, principalmente, del enfermero, la educación y promoción del amamantamiento materno
Dynamical Black Hole Masses of BL Lac Objects from the Sloan Digital Sky Survey
We measure black hole masses for 71 BL Lac objects from the Sloan Digital Sky
Survey with redshifts out to z~0.4. We perform spectral decompositions of their
nuclei from their host galaxies and measure their stellar velocity dispersions.
Black hole masses are then derived from the black hole mass - stellar velocity
dispersion relation. We find BL Lac objects host black holes of similar masses,
~10^{8.5} M_sun, with a dispersion of 0.4 dex, similar to the uncertainties on
each black hole measurement. Therefore, all BL Lac objects in our sample have
the same indistinguishable black hole mass. These 71 BL Lac objects follow the
black hole mass - bulge luminosity relation, and their narrow range of host
galaxy luminosities confirm previous claims that BL Lac host galaxies can be
treated as standard candles. We conclude that the observed diversity in the
shapes of BL Lac object spectral energy distributions is not strongly driven by
black hole mass or host galaxy properties.Comment: 9 pages, 5 figures, 1 table. Accepted for publication in MNRA
Early Science with the Large Millimeter Telescope: an energy-driven wind revealed by massive molecular and fast X-ray outflows in the Seyfert Galaxy IRAS 17020+4544
We report on the coexistence of powerful gas outflows observed in millimeter
and X-ray data of the Radio-Loud Narrow Line Seyfert 1 Galaxy IRAS 17020+4544.
Thanks to the large collecting power of the Large Millimeter Telescope, a
prominent line arising from the 12CO(1-0) transition was revealed in recent
observations of this source. The complex profile is composed by a narrow
double-peak line and a broad wing. While the double-peak structure may be
arising in a disk of molecular material, the broad wing is interpreted as the
signature of a massive outflow of molecular gas with an approximate bulk
velocity of -660 km/s. This molecular wind is likely associated to a
multi-component X-ray Ultra-Fast Outflow with velocities reaching up to ~0.1c
and column densities in the range 10^{21-23.9} cm^-2 that was reported in the
source prior to the LMT observations. The momentum load estimated in the two
gas phases indicates that within the observational uncertainties the outflow is
consistent with being propagating through the galaxy and sweeping up the gas
while conserving its energy. This scenario, which has been often postulated as
a viable mechanism of how AGN feedback takes place, has so far been observed
only in ULIRGs sources. IRAS 17020+4544 with bolometric and infrared luminosity
respectively of 5X10^{44} erg/s and 1.05X10^{11} L_sun appears to be an example
of AGN feedback in a NLSy1 Galaxy (a low power AGN). New proprietary
multi-wavelength data recently obtained on this source will allow us to
corroborate the proposed hypothesis.Comment: Accepted for publication on ApJ Letters, 9 pages, 4 figure
- …