3,076 research outputs found
The Quantum Geometric Phase between Orthogonal States
We show that the geometric phase between any two states, including orthogonal
states, can be computed and measured using the notion of projective
measurement, and we show that a topological number can be extracted in the
geometric phase change in an infinitesimal loop near an orthogonal state. Also,
the Pancharatnam phase change during the passage through an orthogonal state is
shown to be either or zero (mod ). All the off-diagonal geometric
phases can be obtained from the projective geometric phase calculated with our
generalized connection
Kinematics of the Broad-line Region of 3C 273 from a Ten-year Reverberation Mapping Campaign
Despite many decades of study, the kinematics of the broad-line region of
3C~273 are still poorly understood. We report a new, high signal-to-noise,
reverberation mapping campaign carried out from November 2008 to March 2018
that allows the determination of time lags between emission lines and the
variable continuum with high precision. The time lag of variations in H
relative to those of the 5100 Angstrom continuum is days
in the rest frame, which agrees very well with the Paschen- region
measured by the GRAVITY at The Very Large Telescope Interferometer. The time
lag of the H emission line is found to be nearly the same as for
H. The lag of the Fe II emission is days, longer
by a factor of 2 than that of the Balmer lines. The velocity-resolved lag
measurements of the H line show a complex structure which can be
possibly explained by a rotation-dominated disk with some inflowing radial
velocity in the H-emitting region. Taking the virial factor of , we derive a BH mass of and an accretion rate of from the
H line. The decomposition of its images yields a host stellar mass
of , and a ratio of in agreement with the Magorrian relation. In the near
future, it is expected to compare the geometrically-thick BLR discovered by the
GRAVITY in 3C 273 with its spatially-resolved torus in order to understand the
potential connection between the BLR and the torus.Comment: 17 pages, 12 figures, 6 tables, accepted for publication in The
Astrophysical Journa
Evidence for Gender-Specific Transcriptional Profiles of Nigral Dopamine Neurons in Parkinson Disease
Epidemiological data suggest that the male gender is one of the risks factors for the development of Parkinson Disease (PD). Also, differences in the clinical manifestation and the course of PD have been observed between males and females. However, little is known about the molecular aspects underlying gender-specificity in PD. To address this issue, we determined the gene expression profiles of male and female dopamine (DA) neurons in sporadic PD.We analyzed Affymetrix-based microarrays on laser microdissected DA neurons from postmortem brains of sporadic PD patients and age-matched controls across genders. Pathway enrichment demonstrated that major cellular pathways involved in PD pathogenesis showed different patterns of deregulation between males and females with more prominent downregulation of genes related to oxidative phosphorylation, apoptosis, synaptic transmission and transmission of nerve impulse in the male population. In addition, we found upregulation of gene products for metabolic processes and mitochondrial energy consumption in the age-matched male control neurons. On the single cell level, selected data validation using quantitative Real-Time (qRT)-PCR was consistent with microarray raw data and supported some of the observations from data analysis.On the molecular level, our results provide evidence that the expression profiles of aged normal and PD midbrain DA neurons are gender-specific. The observed differences in the expression profiles suggest a disease bias of the male gender, which could be in concordance with clinical observations that the male gender represents a risk factor for sporadic PD. Validation of gene expression by qRT-PCR supported the microarray results, but also pointed to several caveats involved in data interpretation
Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. III. Detection of Fe II Reverberation in Nine Narrow-Line Seyfert 1 Galaxies
This is the third in a series of papers reporting on a large
reverberation-mapping campaign aimed to study the properties of active galactic
nuclei (AGNs) with high accretion rates. We present new results on the
variability of the optical Fe II emission lines in 10 AGNs observed by the
Yunnan Observatory 2.4m telescope during 2012--2013. We detect statistically
significant time lags, relative to the AGN continuum, in nine of the sources.
This accurate measurement is achieved by using a sophisticated spectral fitting
scheme that allows for apparent flux variations of the host galaxy, and several
narrow lines, due to the changing observing conditions. Six of the newly
detected lags are indistinguishable from the Hbeta lags measured in the same
sources. Two are significantly longer and one is slightly shorter. Combining
with Fe II lags reported in previous studies, we find a Fe II
radius--luminosity relationship similar to the one for Hbeta, although our
sample by itself shows no clear correlation. The results support the idea that
Fe II emission lines originate in photoionized gas which, for the majority of
the newly reported objects, is indistinguishable from the Hbeta-emitting gas.
We also present a tentative correlation between the lag and intensity of Fe II
and Hbeta and comment on its possible origin.Comment: 14 pages, 10 figures, accepted for publication in The Astrophysical
Journa
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