19,638 research outputs found
Experimental measurement of photothermal effect in Fabry-Perot cavities
We report the experimental observation of the photothermal effect. The
measurements are performed by modulating the laser power absorbed by the
mirrors of two high-finesse Fabry-Perot cavities. The results are very well
described by a recently proposed theoretical model [M. Cerdonio, L. Conti, A.
Heidmann and M. Pinard, Phys. Rev. D 63 (2001) 082003], confirming the
correctness of such calculations. Our observations and quantitative
characterization of the photothermal effect demonstrate its critical importance
for high sensitivity interferometric displacement measurements, as those
necessary for gravitational wave detection.Comment: 4 pages, 3 figures, submitted to Phys. Rev. Let
Synthetic spectra of H Balmer and HeI absorption lines. I: Stellar library
We present a grid of synthetic profiles of stellar H Balmer and HeI lines at
optical wavelengths with a sampling of 0.3 A. The grid spans a range of
effective temperature 4000 K < Teff < 50000 K, and gravity 0.0 < log g < 5.0 at
solar metallicity. For Teff > 25000 K, NLTE stellar atmosphere models are
computed using the code TLUSTY (Hubeny 1988). For cooler stars, Kurucz (1993)
LTE models are used to compute thesynthetic spectra. The grid includes the
profiles of the high-order hydrogen Balmer series and HeI lines for effective
temperatures and gravities that have not been previously synthesized. The
behavior of H8 to H13 and HeI 3819 with effective temperature and gravity is
very similar to that of the lower terms of the series (e.g. Hb) and the other
HeI lines at longer wavelengths; therefore, they are suited for the
determination of the atmospheric parameters of stars. These lines are
potentially important to make predictions for these stellar absorption features
in galaxies with active star formation. Evolutionary synthesis models of these
lines for starburst and post-starburst galaxies are presented in a companion
paper. The full set of the synthetic stellar spectra is available for retrieval
at our website http://www.iaa.es/ae/e2.html and
http://www.stsci.edu/science/starburst/ or on request from the authors at
[email protected]: To be published in ApJS. 28 pages and 12 figure
Possible unconventional superconductivity in substituted BaFeAs revealed by magnetic pair-breaking studies
The possible existence of a sign-changing gap symmetry in
BaFeAs-derived superconductors (SC) has been an exciting topic of
research in the last few years. To further investigate this subject we combine
Electron Spin Resonance (ESR) and pressure-dependent transport measurements to
investigate magnetic pair-breaking effects on BaFeAs (
Mn, Co, Cu, and Ni) single crystals. An ESR signal, indicative of the presence
of localized magnetic moments, is observed only for Cu and Mn compounds,
which display very low SC transition temperature () and no SC,
respectively. From the ESR analysis assuming the absence of bottleneck effects,
the microscopic parameters are extracted to show that this reduction of
cannot be accounted by the Abrikosov-Gorkov pair-breaking expression for a
sign-preserving gap function. Our results reveal an unconventional spin- and
pressure-dependent pair-breaking effect and impose strong constraints on the
pairing symmetry of these materials
Heralded processes on continuous-variable spaces as quantum maps
Conditional evolution is crucial for generating non-Gaussian resources for
quantum information tasks in the continuous variable scenario. However, tools
are lacking for a convenient representation of heralded process in terms of
quantum maps for continuous variable states, in the same way as Wigner
functions are able to give a compact description of the quantum state. Here we
propose and study such a representation, based on the introduction of a
suitable transfer function to describe the action of a quantum operation on the
Wigner function. We also reconstruct the maps of two relevant examples of
conditional process, that is, noiseless amplification and photon addition, by
combining experimental data and a detailed physical model. This analysis allows
to fully characterize the effect of experimental imperfections in their
implementations.Comment: 9 pages, 8 figures. Minor change
Synchronisation schemes for two dimensional discrete systems
In this work we consider two models of two dimensional discrete systems
subjected to three different types of coupling and analyse systematically the
performance of each in realising synchronised states.We find that linear
coupling effectively introduce control of chaos along with
synchronisation,while synchronised chaotic states are possible with an additive
parametric coupling scheme both being equally relevant for specific
applications.The basin leading to synchronisationin the initial value plane and
the choice of parameter values for synchronisation in the parameter plane are
isolatedin each case.Comment: 17 pages 8 figures. submitted to physica script
XMM-Newton Spectra of Intermediate-Mass Black Hole Candidates: Application of a Monte-Carlo Simulated Model
We present a systematic spectral analysis of six ultraluminous X-ray sources
(NGC1313 X-1/X-2, IC342 X-1, HoIX X-1, NGC5408 X-1 and NGC3628 X-1) observed
with XMM-Newton Observatory. These extra-nuclear X-ray sources in nearby
late-type galaxies have been considered as intermediate-mass black hole
candidates. We have performed Monte-Carlo simulations of Comptonized
multi-color black-body accretion disks. This unified and self-consistent
spectral model assumes a spherically symmetric, thermal corona around each disk
and accounts for the radiation transfer in the Comptonization. We find that the
model provides satisfactory fits to the XMM-Newton spectra of thesources. The
characteristic temperatures of the accretion disks (T_in), for example, are in
the range of ~ 0.05-0.3 keV, consistent with the intermediate-mass black hole
interpretation. We find that the black hole mass is typically about a few times
10^3 M_\odot and has an accretion rate ~ 10^{-6} - 10^{-5} M_\odot yr^{-1}. For
the spectra considered here, we find that the commonly used multi-color
black-body accretion disk model with an additive power law component, though
not physical, provides a good mathematical approximation to the Monte-Carlo
simulated model. However, the latter model provides additional constraints on
the properties of the accretion systems, such as the disk inclination angles
and corona optical depths.Comment: 23 pages, 4 figures, 5 tables. ApJ accepted, July 2004 issu
Analisis Faktor-faktor Yang Mempengaruhi Kepatuhan Pengisian Rekam Medis Di Rumah Sakit Gigi Dan Mulut Pendidikan Umy
Background: RSGMP UMY been utilizing computer-based information systems and manually medical records. Problems often arise in filing medical records are incomplete filling process. The purpose of this study to find out the problems in filling medical records, and analyzes the factors that influence adherence charging medical records in RSGMP UMY. Method: using quantitative and qualitative methods. Subjects in research is coass and physician mentors in RSGMP UMY. Research object is files medical records in 2012. Quantitative data using descriptive statistics, qualitative data using a coding interview. Results: The complete medical records of 236 (64.84%), and incomplete medical records of 128 (35.16%). Incomplete completeness aspect is the identity of the patients (3.85%), the date and time (1.65%), the name and signature of the doctor (23.35%), and correction of errors (16.21%). Medical record is incomplete due to factors selecting lecturers, lack of faculty, number of patients, limited time, knowledge, and attitudes operator. Conclusion: Factors affecting compliance to medical records in RSGM-P UMY is knowledge, limited time, operator attitude, sum of patient, and motivation
The Size of the Narrow-Line Emitting Region in the Seyfert 1 Galaxy NGC 5548 from Emission-Line Variability
The narrow [O III] 4959, 5007 emission-line fluxes in the spectrum of the
well-studied Seyfert 1 galaxy NGC 5548 are shown to vary with time. From this
we show that the narrow line-emitting region has a radius of only 1-3 pc and is
denser (n ~ 10^5 cm^{-3}) than previously supposed. The [O III] line width is
consistent with virial motions at this radius given previous determinations of
the black hole mass.Since the [O III] emission-line flux is usually assumed to
be constant and is therefore used to calibrate spectroscopic monitoring data,
the variability has ramifications for the long-term secular variations of
continuum and emission-line fluxes, though it has no effect on shorter-term
reverberation studies. We present corrected optical continuum and broad Hbeta
emission-line light curves for the period 1988 to 2008.Comment: 11 pages, 5 figures, 6 tables. Accepted for publication in Ap
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