9,193 research outputs found
Separation and quantification of alkylphosphocholines by reversed phase high performance liquid chromatography
The goldstone and goldstino of supersymmetric inflation
We construct the minimal effective field theory (EFT) of supersymmetric
inflation, whose field content is a real scalar, the goldstone for
time-translation breaking, and a Weyl fermion, the goldstino for supersymmetry
(SUSY) breaking. The inflating background can be viewed as a single
SUSY-breaking sector, and the degrees of freedom can be efficiently
parameterized using constrained superfields. Our EFT is comprised of a chiral
superfield X_NL containing the goldstino and satisfying X_NL^2 = 0, and a real
superfield B_NL containing both the goldstino and the goldstone, satisfying
X_NL B_NL = B_NL^3 = 0. We match results from our EFT formalism to existing
results for SUSY broken by a fluid background, showing that the goldstino
propagates with subluminal velocities. The same effect can also be derived from
the unitary gauge gravitino action after embedding our EFT in supergravity. If
the gravitino mass is comparable to the Hubble scale during inflation, we
identify a new parameter in the EFT related to a time-dependent phase of the
gravitino mass parameter. We briefly comment on the leading contributions of
goldstino loops to inflationary observables.Comment: 32 pages, 2 figures. v3: clarifications and references added. Matches
JHEP version. v2: typos fixed, footnote and references adde
Can the Market Add and Subtract? Mispricing in Tech Stock Carve-Outs
Recent equity carve-outs in US technology stocks appear to violate a basic premise of financial theory: identical assets have identical prices. In our 1998-2000 sample, holders of a share of company A are expected to receive x shares of company B, but the price of A is less than x times the price of B. A prominent example involves 3Com and Palm. Arbitrage does not eliminate these blatant mispricing due to short sale constraints, so that B is overpriced but expensive or impossible to sell short. Evidence from options prices shows that shorting costs are extremely high, eliminating exploitable arbitrage opportunities.
Systematics of the temperature-dependent inter-plane resistivity in Ba(FeT)As with T= Rh, Ni, and Pd
Temperature-dependent inter-plane resistivity, , was measured
systematically as a function of transition metal substitution in the
iron-arsenide superconductors Ba(FeT)As, = Ni, Pd, Rh.
The data are compared with the behavior found in
Ba(FeCo)As, revealing resistive signatures of pseudogap. In
all compounds we find resistivity crossover at a characteristic pseudogap
temperature from non-metallic to metallic temperature dependence on
cooling. Suppression of proceeds very similar in cases of Ni and Pd
doping and much faster than in similar cases of Co and Rh doping. In cases of
Co and Rh doping an additional minimum in the temperature-dependent
emerges for high dopings, when superconductivity is completely suppressed.
These features are consistent with the existence of a charge gap covering part
of the Fermi surface. The part of the Fermi surface affected by this gap is
notably larger for Ni and Pd doped compositions than in Co and Rh doped
compounds
Shock wave study and theoretical modeling of the thermal decomposition of c-C4F8
The thermal dissociation of octafluorocyclobutane, c-C4F8, was studied in shock waves over the range 1150-2300 K by recording UV absorption signals of CF2. It was found that the primary reaction nearly exclusively produces 2 C2F4 which afterwards decomposes to 4 CF2. A primary reaction leading to CF2 + C3F6 is not detected (an upper limit to the yield of the latter channel was found to be about 10 percent). The temperature range of earlier single pulse shock wave experiments was extended. The reaction was shown to be close to its high pressure limit. Combining high and low temperature results leads to a rate constant for the primary dissociation of k1 = 1015.97 exp(-310.5 kJ mol-1/RT) s-1 in the range 630-1330 K, over which k1 varies over nearly 14 orders of magnitude. Calculations of the energetics of the reaction pathway and the rate constants support the conclusions from the experiments. Also they shed light on the role of the 1,4-biradical CF2CF2CF2CF2 as an intermediate of the reaction.Fil: Cobos, Carlos Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Hintzer, K.. Dyneon Gmbh; AlemaniaFil: Sölter, L.. Universität Göttingen; AlemaniaFil: Tellbach, E.. Universität Göttingen; AlemaniaFil: Thaler, A.. Dyneon Gmbh; AlemaniaFil: Troe, J.. Universität Göttingen; Alemania. Max-Planck-Institut fu¨r biophysikalische Chemie; Alemani
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