246,938 research outputs found
Fano-ADC(2,2) method for electronic decay rates
Fano-ADC is a family of ab initio methods for prediction of electronic decay
widths in excited, singly- and doubly-ionized systems. It has been particularly
successful in elucidating the geometry dependence of the inter-atomic decay
widths in clusters and facilitated prediction of new electronic decay
phenomena. However, the available Fano-ADC schemes are limited to the second
order treatment of the initial state and fist-order treatment of the final
states of the decay. This confines the applicability of the Fano-ADC approach
to first-order decay processes, e.g. normal but not double Auger decay, and
compromises the numerical accuracy of the schemes through the unbalanced
treatment of electronic correlation. Here we introduce the ADC(2,2)
approximation for singly ionized states which describes both initial and final
states of the decay up to second order. We use the new scheme to construct the
Fano-ADC(2,2) approximation for the decay widths and show that it provides
superior accuracy for the decay widths of a series of processes. Moreover, the
Fano-ADC(2,2) method provides access to second-order decay processed, such as
double Auger decay, which are qualitatively beyond reach of the previously
available Fano-ADC implementations.Comment: 41 pages, 4 figure
Private-Law Models for Official Immunity
A method for correcting matching errors in an ADC is presented. The method uses the unknown input data from the application and does not require any test signal. Two algorithms for implementing the method are compared. One algorithm is general and works on any type of ADC. The other algorithm utilizes the subranged architecture of a specific ADC and is very simple to implement in hardware. The signal quality is similar for both algorithms
A 0.45pJ/conv-step 1.2Gs/s 6b full-Nyquist non-calibrated flash ADC in 45nm CMOS and its scaling behavior
A 6-bit 1.2 Gs/s non-calibrated flash ADC in a standard 45nm CMOS process, that achieves 0.45pJ/conv-step at full Nyquist bandwidth, is presented. Power efficient operation is achieved by a full optimization of amplifier blocks, and by innovations in the comparator and encoding stage. The performance of a non-calibrated flash ADC is directly related to device properties;\ud
a scaling analysis of our ADC in and across CMOS technologies gives insight into the excellent usability of 45nm technology for AD converter design
A 76nW, 4kS/s 10-bit SAR ADC with offset cancellation for biomedical applications
This paper presents a 10-bit fully-differential rail-to-rail successive approximation (SAR) ADC designed for biomedical applications. The ADC, fabricated in a 180nm HV CMOS technology, features low switching energy consumption and employs a time-domain comparator which includes an offset cancellation mechanism. The power dissipated by the ADC is 76.2nW at 4kS/s and achieves 9.5 ENOB.Ministerio de Economía y Competitividad TEC2012-33634Office of Naval Research (USA) N0001414135
A 10-bit Charge-Redistribution ADC Consuming 1.9 μW at 1 MS/s
This paper presents a 10 bit successive approximation ADC in 65 nm CMOS that benefits from technology scaling. It meets extremely low power requirements by using a charge-redistribution DAC that uses step-wise charging, a dynamic two-stage comparator and a delay-line-based controller. The ADC requires no external reference current and uses only one external supply voltage of 1.0 V to 1.3 V. Its supply current is proportional to the sample rate (only dynamic power consumption). The ADC uses a chip area of approximately 115--225 μm2. At a sample rate of 1 MS/s and a supply voltage of 1.0 V, the 10 bit ADC consumes 1.9 μW and achieves an energy efficiency of 4.4 fJ/conversion-step
The inner mass distribution of late-type spiral galaxies from SAURON stellar kinematic maps
We infer the central mass distributions within 0.4-1.2 disc scale lengths of
18 late-type spiral galaxies using two different dynamical modelling approaches
- the Asymmetric Drift Correction (ADC) and axisymmetric Jeans Anisotropic
Multi-gaussian expansion (JAM) model. ADC adopts a thin disc assumption,
whereas JAM does a full line-of-sight velocity integration. We use stellar
kinematics maps obtained with the integral-field spectrograph SAURON to derive
the corresponding circular velocity curves from the two models. To find their
best-fit values, we apply Markov Chain Monte Carlo (MCMC) method. ADC and JAM
modelling approaches are consistent within 5% uncertainty when the ordered
motions are significant comparable to the random motions, i.e,
is locally greater than 1.5. Below this value,
the ratio gradually increases with
decreasing , reaching . Such conditions indicate that the stellar masses of
the galaxies in our sample are not confined to their disk planes and likely
have a non-negligible contribution from their bulges and thick disks.Comment: 44 pages, 60 figures, MNRAS accepted. The ADC-MCMC and JAM-MCMC
python codes are available at: https://github.com/Kalinova/Dyn_models. The
Multi-Gaussian Expansion (MGE) results are also available in the Appendi
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