178 research outputs found
An outflow perpendicular to the radio jet in the Seyfert nucleus of NGC5929
We report the observation of an outflow perpendicular to the radio jet in
near-infrared integral field spectra of the inner 250 pc of the Seyfert 2
galaxy NGC 5929. The observations were obtained with the Gemini Near infrared
Integral Field Spectrograph at a spatial resolution of ~20 pc and spectral
resolution R~5300 and reveal a region 50 pc wide crossing the nucleus and
extending by 300 pc perpendicularly to the known radio jet in this galaxy.
Along this structure - which we call SE-NW strip - the emission-line profiles
show two velocity components, one blueshifted and the other redshifted by -150
km/s and 150 km/s, respectively, relative to the systemic velocity. We
interpret these two components as due to an outflow perpendicular to the radio
jet, what is supported by low frequency radio emission observed along the same
region. We attribute this feature to the interaction of ambient gas with an
"equatorial outflow" predicted in recent accretion disk and torus wind models.
Perpendicularly to the SE-NW strip, thus approximately along the radio jet,
single component profiles show blueshifts of ~-150 km/s to the north-east and
similar redshifts to the south-west, which can be attributed to gas
counter-rotating relative to the stellar kinematics. More double-peaked
profiles are observed in association with the two radio hot-spots, attributed
to interaction of the radio jet with surrounding gas.Comment: Accepted for publication in ApJL; 5 page
Feeding Versus Feedback in AGNs from Near-Infrared IFU Observations: The Case of Mrk79
We have mapped the gaseous kinematics and the emission-line flux
distributions and ratios from the inner ~680pc radius of the Seyfert 1 galaxy
Mrk79, using two-dimensional (2D) near-IR J- and Kl-band spectra obtained with
the Gemini instrument NIFS at a spatial resolution of ~100pc and velocity
resolution of ~40km/s. The molecular hydrogen flux distribution presents two
spiral arms extending by ~700pc, one to the north and another to the south of
the nucleus, with an excitation indicating heating by X-rays from the central
source. The low velocity dispersion (sigma~50km/s) and rotation pattern
supports a location of the H2 gas in the disk of the galaxy. Blueshifts
observed along the spiral arm in the far side of the galaxy and redshifts in
the spiral arm in the near side, suggest that the spiral arms are feeding
channels of H2 to the inner 200pc. From channel maps along the H2 l2.1218um
emission-line profile we estimate a mass inflow rate of ~4E-3 M_Sun/year, which
is one order of magnitude smaller than the mass accretion rate necessary to
power the AGN of Mrk79. The emission from the ionized gas (traced by Pabeta and
[FeII]l1.2570um emission lines) is correlated with the radio jet and with the
narrow-band [OIII] flux distribution. Its kinematics shows both rotation and
outflows to the north and south of the nucleus. The ionized gas mass outflow
rate through a cross section with radius ~320pc located at a distance of ~455pc
from the nucleus is 3.5 MSun/year, which is much larger than the AGN mass
accretion rate, indicating that most of the outflowing gas originates in the
interstellar medium surrounding the galaxy nucleus, which is pushed away by a
nuclear jet.Comment: Accepted by MNRA
Outflows, Inflows and Young Stars in the inner 200 pc of the Seyfert galaxy NGC 2110
We present a two-dimensional mapping of stellar population age components,
emission-line fluxes, gas excitation and kinematics within the inner
pc of the Seyfert 2 galaxy NGC 2110. We used the Gemini North Integral Field
Spectrograph (NIFS) in the J and K bands at a spatial resolution of
pc. The unresolved nuclear continuum is originated in combined contributions of
young stellar population (SP; age Myr), a featureless AGN continuum
and hot dust emission. The young-intermediate SP (age Myr) is
distributed in a ring-shaped structure at pc from the nucleus,
which is roughly coincident with the lowest values of the stellar velocity
dispersion. In the inner pc the old SP (age Gyr) is dominant.
The [FeII]1.25m emission-line flux distribution is correlated with the
radio emission and its kinematics comprise two components, one from gas
rotating in the galaxy plane and another from gas in outflow within a bicone
oriented along north-south. These outflows seem to originate in the interaction
of the radio jet with the ambient gas producing shocks that are the main
excitation mechanism of the [FeII] emission. We estimate: (1) an ionized gas
mass outflow rate of M/yr at 70 pc from the nucleus;
and (2) a kinetic power for the outflow of only 0.05% of the AGN bolometric
luminosity implying weak feedback effect on the galaxy.Comment: Accepted for publication in MNRA
The fiftieth anniversary of physics at UFSM: a gender analysis of graduates
The Federal University of Santa Maria (UFSM - Universidade Federal de Santa
Maria) has trained more than 600 undergraduate and 200 Ph.D. students, becoming
a reference in physics training at the Rio Grande do Sul central region. In
this work we present a gender analysis of the UFSM graduated students from both
levels. The number of graduated students of the female gender has been rising
with time and is significatively bigger than the number observed nationally in
both levels. The mean values are 35%, 37%, 28%, 42% e 39% for the courses
physics teaching (daytime), physics teaching (nightime), physics, master and
doctorate, respectively. We also observe an increase in the participation of
female students in graduate courses, when comparing to undergraduate courses,
unlike what is observed in the national average numbers. Considering only the
last 5 years the number of graduated students reaches 50% in the physics
teaching (daytime) and master courses. Although this study is of a local
nature, it reinforces the need for the dissemination of data regarding the
gender of graduates by all universities, allowing to conduct general gender
studies.Comment: Main text in Portuguese; Published in Ci\^encia e Natura
(https://periodicos.ufsm.br/cienciaenatura/article/view/31793
PROFIT: a new alternative for emission-line PROfile FITting
I briefly describe a simple routine for emission-line profiles fitting by
Gaussian curves or Gauss-Hermite series. The PROFIT (line-PROfile FITting)
routine represent a new alternative for use in fits data cubes, as those from
Integral Field Spectroscopy or Fabry-Perot Interferometry, and may be useful to
better study the emission-line flux distributions and gas kinematics in
distinct astrophysical objects, such as the central regions of galaxies and
star forming regions. The PROFIT routine is written in IDL language and is
available at http://www.ufsm.br/rogemar/software.html.
The PROFIT routine was used to fit the [Fe II]1.257um emission-line profiles
for about 1800 spectra of the inner 350 pc of the Seyfert galaxy Mrk1066
obtained with Gemini NIFS and shows that the line profiles are better
reproduced by Gauss-Hermite series than by the commonly used Gaussian curves.
The two-dimensional map of the h_3 Gauss-Hermite moment shows its highest
absolute values in regions close to the edge of the radio structure. These high
values may be originated in an biconical outflowing gas associated with the
radio jet - previously observed in the optical [O III] emission. The analysis
of this kinematic component indicates that the radio jet leaves the center of
the galaxy with the north-west side slightly oriented towards us and the
south-east side away from us, being partially hidden by the disc of the galaxy.Comment: Accepted for publication Astrophysics & Space Science - 7 pges; 4
Fig
Feeding Versus Feedback in NGC1068 probed with Gemini NIFS. I. Excitation
We present emission-line flux distributions and ratios for the inner 200pc of
the narrow-line region of the Seyfert2 galaxy NGC1068, using observations
obtained with the Gemini Near-infrared Integral Field Spectrograph (NIFS) in
the J, H and K bands at a spatial resolution of 10pc and spectral resolution of
5300. The molecular gas emission - traced by the K-band H_2 emission lines -
outlines an off-centered circumnuclear ring with a radius of 100pc showing
thermal excitation. The ionized gas emission lines show flux distributions
mostly outlining the previously known [OIII]5007 ionization bicone. But while
the flux distributions in the HI and HeII emission lines are very similar to
that observed in [OIII], the flux distribution in the [FeII] emission lines is
more extended and broader than a cone close to the nucleus, showing a "double
bowl" or `hourglass" structure". This difference is attributed to the fact that
the [FeII] emission, besides coming from the fully ionized region, comes also
from the more extended partially ionized regions, in gas excited mainly by
X-rays from the active galactic nucleus. A contribution to the [FeII] emission
from shocks along the bicone axis to NE and SW of the nucleus is also supported
by the enhancement of the [FeII](1.2570)/[PII](1.1885) and
[FeII](1.2570)/Pabeta emission-line ratios at these locations and is attributed
to the interaction of the radio jet with the NLR. The mass of ionized gas in
the inner 200pc of NGC1068 is MHII~2.2E4 M_Sun, while the mass of the H2
emitting gas is only M_{H2}~29M_Sun. Taking into account the dominant
contribution of the cold molecular gas, we obtain an estimate of the total
molecular gas mass of Mcold~2E7 M_Sun.Comment: accepeted for publication in MNRA
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