1,512 research outputs found
Development of a Polymeric Planar Microwell Device (pMALDI CHIP) for Enhancing Protein Analysis in Combination with Maldi-Tof/Ms Instrumentation
Se desarrolló un Micro ARREGLO polimérico para que usando sus propiedades químicas y por medio de interacciones entre la superficie y las proteínas; estas últimas pueden ser pre concentradas para un análisis posterior vía MALDI – TOF/MS.International Max Planch Research SchoolTesi
Origin of non-keplerian motions of masers in NGC 1068
We demonstrate that the ``sub-keplerian'' rotation curve of maser spots in
NGC 1068 can be explained by the gravitational attraction of the disc orbiting
the central black hole. Possible parameters matching observations are: black
hole mass of 12 million solar masses, disc outer edge > 1.3 pc, aspect ratio in
the range 0.003 to 0.3, surface density varying approximately as 1/R, and disc
mass of about 9.4 million solar masses. The physical conditions required for
the excitation of masers are fulfilled, and the outer disc would stand in a
gravitationally marginally stable state.Comment: 4 pages; accepted in A&A Letter
Tuning paramagnetic spin-excitations of single adatoms
Around 50 years ago, Doniach [Proc. Phys. Soc. 91, 86 (1967)] predicted the
existence of paramagnons in nearly ferromagnetic materials, recently measured
in bulk Pd [Phys. Rev. Lett. 105, 027207 (2010)]. Here we predict the analogous
effect for single adatoms, namely paramagnetic spin-excitations (PSE). Based on
time-dependent density functional theory, we demonstrate that these overdamped
excitations acquire a well-defined peak structure in the meV energy region when
the adatom's Stoner criterion for magnetism is close to the critical point. In
addition, our calculations reveal a subtle tunability and enhancement of PSE by
external magnetic fields, exceeding by far the response of bulk paramagnons and
even featuring the atomic version of a quantum phase transition. We further
demonstrate how PSE can be detected as moving steps in the
signal of state-of-the-art inelastic scanning tunneling spectroscopy, opening a
potential route for experimentally accessing fundamental electronic properties
of non-magnetic adatoms, such as the Stoner parameter.Comment: 6 pages, 3 figure
Inverting the Supersymmetric Standard Model Spectrum: from Physical to Lagrangian Ino Parameters
We examine the possibility of recovering the supersymmetric (and soft
supersymmetry breaking) Lagrangian parameters as direct {\em analytical}
expressions of appropriate physical masses, for the unconstrained (but CP and
R-parity conserving) minimal supersymmetric standard model. We concentrate
mainly on the algebraically non-trivial "inversion" for the ino parameters, and
obtain, for given values of , simple analytical expressions for the
, and parameters in terms of three arbitrary input physical
masses, namely either two chargino and one neutralino masses, or alternatively
one chargino and two neutralino masses. We illustrate and discuss in detail the
possible occurrence of ambiguities in this reconstruction. The dependence of
the resulting ino Lagrangian parameters upon physical masses is illustrated,
and some simple generic behaviour uncovered in this way. We finally briefly
sketch generalizing such an inversion to the full set of MSSM Lagrangian
parameters.Comment: Latex, 28 pages, 6 figures, 1 table, some typos corrected, one
paragraph extended in section 4.2. Version to appear in Phys. Rev.
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