1,918 research outputs found
Optical conductivity of alpha-Mn
The optical constants were measured at room temperature in the photon-energy range 0.6 to 6.5 eV on evaporated thin films. Evaporation conditions were chosen that gave the alpha-Mn crystal structure with reasonably large grains. The optical conductivity was separated into intraband and interband contributions by fitting to the Drude formula at low energies. The results are anomalous in comparison to other 3d transition metals. The free-electron lifetime is exceptionally sort (in agreement with the large dc resistivity of Mn), and the interband transitions seem unusually weak at the lower energies. Possible explanations related to the complicated crystal structure of alpha-Mn are discussed
Optical conductivity of amorphous Ta and beta-Ta films
Tantalum films evaporated in high vacuum onto liquid-nitrogen-cooled substrates had an amorphous structure that persisted even after warming to room temperature. The optical conductivity (as well as the dc conductivity) of the amorphous films differed significantly from that of the bcc films
Shuffle on array languages generated by array grammars
Motivated by the studies done by G. Siromoney et al. (1973) and Alexan-
dru Mateescu et al. (1998) we examine the language theoretic results related to shuf- fle on trajectories by making use of Siromoney array grammars such as (R : R)AG, (R : C F )AG, (C F : R)AG, (C F : C F )AG, (C S : R)AG, (C S : C S)AG and (C F : C S)AG which are more powerful than the Siromoney matrix grammars (1972)
and are used to make digital pictures
Cross-correlations in NMR
The phenomenon of nuclear magnetic resonance (NMR) involves placing magnetically active nuclear spins embedded in a gas, liquid or solid phase in a constant, large and uniform magnetic field, causing a splitting of magnetic energy levels.Energy can be absorbed by these spins from a resonant radiofrequency (RF) field causing transitions between these levels. Immediately following this absorption, the spins start to exchange this energy among themselves and also pass it on to other degrees of freedom, that is, the spins start to relax. Relaxation is central to the NMR phenomenon as a necessary prerequisite for its detection. It is also used as a probe for obtaining information on the local environment of the spins and about the dynamics of the molecules in which the spins are embedded
Manajemen Retribusi Izin Mendirikan Bangunan (IMB) Dalam Meningkatkan Pendapatan Asli Daerah Di Kabupaten Maluku Tengah
Management of Building Permit Retribution (IMB) in increasing Local Revenue in Central Maluku Regency. This research is a descriptive qualitative research that aims to analyze the management of Building Construction Permit (IMB) retribution in increasing local revenue in Central Maluku Regency. This research was conducted at the Public Works and Spatial Planning Office of Central Maluku Regency. Primary data was collected through interviews with a number of informants involved in the Management of Building Permit Retribution (IMB) in Central Maluku Regency. The results showed that in the planning stage of building permit retribution (IMB), a target is determined for each year which is influenced by whether or not the target was achieved in the previous year, and in 2022 according to preliminary research the target was not achieved. The reason is that the community is still indifferent about IMB so it must be followed up. In the management team itself, there is a division of tasks for each member, and there is a Standard Operating Procedure (SOP). Although in its implementation, to carry out the SOP, there are still obstacles. As for the fulfillment of the target itself, due to public indifference to IMB, officers must go directly to the scene. In line with this non-compliance, patrols are carried out by a joint team of a number of parties to see and control whether or not there are IMBs on buildings that are being built. And based on local regulations that regulate there are a number of sanctions that can threaten those who violate it. So it is actually necessary to conduct a thorough socialization to the community related to IMB, its management, and other technical matters.
Unpolarized structure functions at Jefferson Lab
Over the past decade measurements of unpolarized structure functions at
Jefferson Lab with unprecedented precision have significantly advanced our
knowledge of nucleon structure. These have for the first time allowed
quantitative tests of the phenomenon of quark-hadron duality, and provided a
deeper understanding of the transition from hadron to quark degrees of freedom
in inclusive scattering. Dedicated Rosenbluth-separation experiments have
yielded high-precision transverse and longitudinal structure functions in
regions previously unexplored, and new techniques have enabled the first
glimpses of the structure of the free neutron, without contamination from
nuclear effects.Comment: 21 pages, 9 figures; typo in Eq. (3) corrected, references added; to
appear in J. Phys. Conf. Proc. "New Insights into the Structure of Matter:
The First Decade of Science at Jefferson Lab", eds. D. Higinbotham, W.
Melnitchouk, A. Thoma
Measurement of the EMC Effect in the Deuteron
We determined the structure function ratio RdEMC=Fd2/(Fn2+Fp2) from recently published Fn2/Fd2 data taken by the BONuS experiment using CLAS at Jefferson Lab. This ratio deviates from unity, with a slope dRdEMC/dx=−0.10 ± 0.05 in the range of Bjorken x from 0.35 to 0.7, for invariant mass W\u3e1.4 GeV and Q2\u3e1 GeV2 . The observed EMC effect for these kinematics is consistent with conventional nuclear physics models that include off-shell corrections, as well as with empirical analyses that find the EMC effect proportional to the probability of short-range nucleon-nucleon correlations
AEGIS: New Evidence Linking Active Galactic Nuclei to the Quenching of Star Formation
Utilizing Chandra X-ray observations in the All-wavelength Extended Groth
Strip International Survey (AEGIS) we identify 241 X-ray selected Active
Galactic Nuclei (AGNs, L > 10^{42} ergs/s) and study the properties of their
host galaxies in the range 0.4 < z < 1.4. By making use of infrared photometry
from Palomar Observatory and BRI imaging from the Canada-France-Hawaii
Telescope, we estimate AGN host galaxy stellar masses and show that both
stellar mass and photometric redshift estimates (where necessary) are robust to
the possible contamination from AGNs in our X-ray selected sample. Accounting
for the photometric and X-ray sensitivity limits of the survey, we construct
the stellar mass function of X-ray selected AGN host galaxies and find that
their abundance decreases by a factor of ~2 since z~1, but remains roughly flat
as a function of stellar mass. We compare the abundance of AGN hosts to the
rate of star formation quenching observed in the total galaxy population. If
the timescale for X-ray detectable AGN activity is roughly 0.5-1 Gyr--as
suggested by black hole demographics and recent simulations--then we deduce
that the inferred AGN "trigger" rate matches the star formation quenching rate,
suggesting a link between these phenomena. However, given the large range of
nuclear accretion rates we infer for the most massive and red hosts, X-ray
selected AGNs may not be directly responsible for quenching star formation.Comment: 12 pages. Submitted to ApJ. Comments welcom
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