Comment on ``Inflation and flat directions in modular invariant superstring effective theories''

The inflation model of Gaillard, Lyth and Murayama is revisited, with a systematic scan of the parameter space for dilaton stabilization during inflation.Comment: 7 pages, 2 figure

Late-time creation of gravitinos from the vacuum

Starting with the vacuum fluctuation, it is known that gravitinos will be created just after inflation, with number density $\sim 10^{-2}M^3$ where $M$ is the mass of the inflaton. Here, we argue that creation may be expected to continue, maintaining about the same number density, until a usually much later epoch. This epoch is either the `intermediate epoch' when Hubble parameter falls below the gravitino mass, or the reheat epoch if that is earlier. We verify that such late-time creation indeed occurs if only a single chiral superfield is relevant, using the description of the helicity 1/2 gravitino provided recently by Kallosh et. al. (hep-th/9907124) and Giudice et. al. (hep-ph/9907510). Arguments are presented in favor of late-time creation in the general case. For the usual inflation models, $M$ is rather large and gravitinos from late-time creation are so abundant that a subsequent era of thermal inflation is needed to dilute them.Comment: 9 pages. As it will appear in PLB. Small typos corrected, a sign discrepancy cleared up, nothing significan

Scheduling the installation of the LHC injection lines

The installation of the two Large Hadron Collider (LHC) injection lines has to fit within tight milestones of the LHC project and of CERN's accelerator activity in general. For instance, the transfer line from the Super Proton Synchrotron (SPS) to LHC point 8 (to fill the anti-clockwise LHC ring) should be tested with beam before the end of 2004 since the SPS will not run in 2005. It will first serve during the LHC sector test in 2006. Time constraints are also very strong on the installation of the transfer line from the SPS to LHC point 2 (for the clockwise LHC ring): its tunnel is the sole access for the LHC cryo-magnets and a large part of the beam line can only be installed once practically all LHC cryo-magnets are in place. Of course, the line must be operational when the LHC starts. This paper presents the various constraints and how they are taken into account for the logistics and installation planning of the LHC injection lines

The abundance of moduli, modulini and gravitinos produced by the vacuum fluctuation

Moduli, modulini and the gravitino have gravitational-strength interactions, and thermal collisions after reheating create all of them with roughly the same abundance. With their mass of order 100\GeV, corresponding to gravity-mediated supersymmetry breaking, this leads to the well-known bound \gamma T\sub R\lsim 10^9\GeV on the reheat temperature, where $\gamma\leq 1$ is the entropy dilution factor. The vacuum fluctuation also creates these particles, with abundance determined by the solution of the equation for the mode function. Taking the equation in each case to be the one corresponding to a free field, we consider carefully the behaviour of the effective mass during the crucial era after inflation. It may have a rapid oscillation, which does not however affect the particle abundance. Existing estimates are confirmed; the abundance of modulini and (probably) of moduli created from the vacuum is less than from thermal collisions, but the abundance of gravitinos may be much bigger, leading to a tighter bound on $T\sub R$ if supersymmetry breaking is gravity-mediated. It is noted that in the case of gauge-mediated supersymmetry breaking, the abundance of the gravitino may be sufficient to make it a dark matter candidate.Comment: 14 pages. v3 as it will appear in PL

Consequences of the regular distribution of sainfoin hay on gastrointestinal parasitism with nematodes and on milk production in a dairy goat flock

The objectives of the current study were to examine the potential effects of distribution of sainfoin hay on nematode parasitism in a producing herd and to measure the consequences on milk production. The survey was performed in an experimental herd of 120-dairy-goat farm during a whole 9-month grazing season. Every month, 60 goats received indoors on average 1.36 kg of sainfoin hay for 10 days whereas the 60 remaining goats were used as controls, thus receiving the same amount of lucerne hay at the same time. The nutritional values of both hays were comparable except that concentrations of condensed tannins was higher in sainfoin than in lucerne hay, i.e. 2.52% versus 0.7% of diet DM. Intakes of the two types of hay were recorded along with each period. Individual faecal and blood samples were performed monthly to compare parasitological and pathophysiological parameters in the two groups. Milk yield, fat and protein contents were measured fortnightly. A higher consumption of hay was repeatedly recorded in the sainfoin versus the control group. Irrespective to dietary treatment, nematode egg excretions were low during the whole season. Meanwhile, egg output was significantly lowest in the sainfoin group, but the composition in nematode genera was similar among the two groups. Based on a semi quantitative index for assessment of faecal consistency, a lower faecal dry matter content was also found in goats from the sainfoin group. The two animal groups exhibited similar milk yield, fat and protein contents. The differences in egg excretion between the two groups might be due to higher intake of hay in the barn thus to low consumption of grass, a source of parasite infection, or to the effect of some secondary compounds, like tannins. Whatever the mechanism involved, our results suggest that a regular distribution of sainfoin hay to dairy goats might be associated with a reduction in parasitism with gastrointestinal nematodes, without negative consequences on milk production. © 2005 Elsevier B.V. All rights reserved

Gaugino Condensation with S-Duality and Field-Theoretical Threshold Corrections

We study gaugino condensation in the presence of an intermediate mass scale in the hidden sector. S-duality is imposed as an approximate symmetry of the effective supergravity theory. Furthermore, we include in the K\"ahler potential the renormalization of the gauge coupling and the one-loop threshold corrections at the intermediate scale. It is shown that confinement is indeed achieved. Furthermore, a new running behaviour of the dilaton arises which we attribute to S-duality. We also discuss the effects of the intermediate scale, and possible phenomenological implications of this model.Comment: 19 pages, LaTeX, 3 postscript figures include

Supergravity Radiative Effects on Soft Terms and the μ\mu Term

We compute quadratically divergent supergravity one-loop effects on soft supersymmetry-breaking parameters and the $\mu$ term in generic hidden sector supergravity models. These effects can significantly modify the matching condition for soft parameters at the Planck scale and also provide several new sources of the $\mu$ term which are naturally of order the weak scale. We also discuss some phenomenological implications of these effects, particularly the violation of the scalar mass universality which may lead to dangerous FCNC phenomena, and apply the results to superstring effective supergravity models.Comment: 12 pages, REVTEX. One reference is adde

Beef breed bulls versus selected dual purpose bulls for meat production

International audienc

Semileptonic Hyperon Decays and CKM Unitarity

Using a technique that is not subject to first-order SU(3) symmetry breaking effects, we determine the $V_{us}$ element of the CKM matrix from data on semileptonic hyperon decays. We obtain $V_{us}$ =0.2250(27). This value is of similar precision to the one derived from $K_{l3}$, but higher and in better agreement with the unitarity requirement, $|V_{ud}|^2+|V_{us}|^2+|V_{ub}|^2=1$.Comment: 3 pages, 1 tabl