749 research outputs found
RF System Upgrades to the Advanced Photon Source Linear Accelerator in Support of the Fel Operation
The S-band linear accelerator, which was built to be the source of particles
and the front end of the Advanced Photon Source injector, is now also being
used to support a low-energy undulator test line (LEUTL) and to drive a
free-electron laser (FEL). The more severe rf stability requirements of the FEL
have resulted in an effort to identify sources of phase and amplitude
instability and implement corresponding upgrades to the rf generation chain and
the measurement system. Test data and improvements implemented and planned are
describedComment: LC 2000 (3 pages, 6 figures
Application of ERTS-1 imagery to state wide land information system in Minnesota
There are no author-identified significant results in this report
The politics of in/visibility: carving out queer space in Ul'yanovsk
<p>In spite of a growing interest within sexualities studies in the concept of queer space (Oswin 2008), existing literature focuses almost exclusively on its most visible and territorialised forms, such as the gay scene, thus privileging Western metropolitan areas as hubs of queer consumer culture (Binnie 2004). While the literature has emphasised the political significance of queer space as a site of resistance to hegemonic gender and sexual norms, it has again predominantly focused on overt claims to public space embodied in Pride events, neglecting other less open forms of resistance.</p><p>
This article contributes new insights to current debates about the construction and meaning of queer space by considering how city space is appropriated by an informal queer network in Ulâianovsk. The group routinely occupied very public locations meeting and socialising on the street or in mainstream cafĂ©s in central Ulâianovsk, although claims to these spaces as queer were mostly contingent, precarious or invisible to outsiders. The article considers how provincial location affects tactics used to carve out communal space, foregrounding the importance of local context and collective agency in shaping specific forms of resistance, and questioning ethnocentric assumptions about the empowering potential of visibility.</p>
Geometrically induced modification of surface plasmons in the optical and telecom regimes
We demonstrate that the introduction of a subwavelength periodic modulation
into a metallic structure strongly modifies the guiding characteristics of the
surface plasmon modes supported by the system. Moreover, it is also shown how a
new type of a tightly confined surface plasmon polariton mode can be created by
just milling a periodic corrugation into a metallic ridge placed on top of a
metal surface
Double Spin Asymmetries A_NN and A_SS at sqrt{s}=200 GeV in Polarized Proton-Proton Elastic Scattering at RHIC
We present the first measurements of the double spin asymmetries A_NN and
A_SS at sqrt{s}=200 GeV, obtained by the pp2pp experiment using polarized
proton beams at the Relativistic Heavy Ion Collider (RHIC). The data were
collected in the four momentum transfer t range 0.01<|t|<0.03 (GeV/c)^2. The
measured asymmetries, which are consistent with zero, allow us to estimate
upper limits on the double helicity-flip amplitudes phi_2 and phi_4 at small t
as well as on the difference Delta(sigma_T) between the total cross sections
for transversely polarized protons with antiparallel or parallel spin
orientations.Comment: 13 pages with 3 figures. Final version accepted by Phys. Lett.
Two approximate formulae for the binding energies in Lambda hypernuclei and light nuclei
Two approximate formulae are given for the binding energies in
Lambda-hypernuclei and light nuclei by means of the (reduced) Poeschl-Teller
and the Gaussian central potentials. Those easily programmable formulae combine
the eigenvalues of the transformed Jacobi eigenequation and an application of
the hypervirial theorems.Comment: Accepted for publication in Europhysics Letter
--Dependence of Bond Energies in Double--- Hypernuclei
The -dependence of the bond energy of the
hypernuclear ground states is calculated in a three-body
model and in the Skyrme-Hartree-Fock approach.
Various and -nucleus or potentials
are used and the sensitivity of to the interactions
is discussed. It is shown that in medium and heavy
hypernuclei, is a linear function of
, where is rms radius of the hyperon orbital. It
looks unlikely that it will be possible to extract
interaction from the double- hypernuclear energies only, the
additional information about the -core interaction, in particular, on
is needed.Comment: 11 pages, LaTex, 3 figure
Gamma-Ray Spectroscopy of O and N Hypernuclei via the O reaction
he bound-state level structures of the O and
N hypernuclei were studied by -ray spectroscopy using
a germanium detector array (Hyperball) via the O ()
reaction. A level scheme for O was determined from the
observation of three -ray transitions from the doublet of states
(,) at MeV to the ground-state doublet (,). The
N hypernuclei were produced via proton emission from unbound
states in O . Three -rays were observed and the
lifetime of the state in N was measured by the
Doppler shift attenuation method. By comparing the experimental results with
shell-model calculations, the spin-dependence of the interaction is
discussed. In particular, the measured O ground-state doublet
spacing of 26.4 1.6 0.5 keV determines a small but nonzero strength
of the tensor interaction.Comment: 22 pages, 17 figure
Inseminação artificial em tempo fixo em caprinos leiteiros com sĂȘmen resfriado por 24 ou 48 horas.
Resumo: Avaliou-se a capacidade fertilizante do sĂȘmen caprino resfriado a 5ÂșC por 24 (T24) ou 48 h (T48). Foram utilizados como doadores de sĂȘmen trĂȘs bodes da raça CanĂĄrias. Conclui-se que o sĂȘmen caprino, resfriado por 48 horas a 5ÂșC, tem o mesmo potencial de fertilização do sĂȘmen resfriado por 24 horas a 5ÂșC e que as inseminaçÔes foram realizadas precocemente, para o protocolo sugerido
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