1,036 research outputs found
Basel III C: Internal Risk Models
For financial regulators seeking to use regulatory requirements to manage risk in a banking system, there can be a concern that such requirements crowd out efforts by banks to develop their own risk management systems. One way in which regulators have attempted to solve this problem is to enable banks to use internal risk models to satisfy regulatory requirements. Beginning with the 1996 Market Risk Amendment, the Basel framework has allowed banks to determine the capital charges associated with certain assets using their own internal risk models. But allowing the use of internal risk models has not been without controversy. Where some see an incentive for the development of internal risk management systems better able to address the unique risk profiles of particular banks, others see excessive complexity and uncertainty. And while some financial regulators are beginning to subject banks’ models to greater scrutiny, questions remain about the ability of financial regulators to provide effective oversight of such models
Fluctuations and Correlations of net baryon number, electric charge, and strangeness: A comparison of lattice QCD results with the hadron resonance gas model
We calculate the quadratic fluctuations of net baryon number, electric charge
and strangeness as well as correlations among these conserved charges in
(2+1)-flavor lattice QCD at zero chemical potential. Results are obtained using
calculations with tree level improved gauge and the highly improved staggered
quark (HISQ) actions with almost physical light and strange quark masses at
three different values of the lattice cut-off. Our choice of parameters
corresponds to a value of 160 MeV for the lightest pseudo scalar Goldstone mass
and a physical value of the kaon mass. The three diagonal charge
susceptibilities and the correlations among conserved charges have been
extrapolated to the continuum limit in the temperature interval 150 MeV <T <
250 MeV. We compare our results with the hadron resonance gas (HRG) model
calculations and find agreement with HRG model results only for temperatures
T<= 150 MeV. We observe significant deviations in the temperature range 160 MeV
< T < 170 MeV and qualitative differences in the behavior of the three
conserved charge sectors. At T < 160 MeV quadratic net baryon number
fluctuations in QCD agree with HRG model calculations while, the net electric
charge fluctuations in QCD are about 10% smaller and net strangeness
fluctuations are about 20% larger. These findings are relevant to the
discussion of freeze-out conditions in relativistic heavy ion collisions.Comment: 17 pages, 18 EPS-files, 5 tables, revised version includes continuum
limit extrapolations of off-diagonal susceptibilities, to appear in Phys.
Rev.
Transition Radiation Spectroscopy with Prototypes of the ALICE TRD
We present measurements of the transition radiation (TR) spectrum produced in
an irregular radiator at different electron momenta. The data are compared to
simulations of TR from a regular radiator.Comment: 4 pages, 5 Figures, Proceedings for "TRDs for the 3rd millennium"
(Sept. 4-7, 2003, Bari, Italy
- …