High-Precision Thermodynamics and Hagedorn Density of States

We compute the entropy density of the confined phase of QCD without quarks on the lattice to very high accuracy. The results are compared to the entropy density of free glueballs, where we include all the known glueball states below the two-particle threshold. We find that an excellent, parameter-free description of the entropy density between 0.7Tc and Tc is obtained by extending the spectrum with the exponential spectrum of the closed bosonic string.Comment: 4 pages, 3 figure

Observation of the Cosmic Ray Electron- Positron Ratio from 100 Mev to 3 Bev in 1964

Balloon flight data on cosmic ray electron- positron ratio from 100 MeV to 3 Be

Gap formation and soft phonon mode in the Holstein model

We investigate electron-phonon coupling in many-electron systems using dynamical mean-field theory in combination with the numerical renormalization group. This non-perturbative method reveals significant precursor effects to the gap formation at intermediate coupling strengths. The emergence of a soft phonon mode and very strong lattice fluctuations can be understood in terms of Kondo-like physics due to the development of a double-well structure in the effective potential for the ions

NICMOS2 hubble space telescope observations of the embedded cluster associated with Mon R2: Constraining the substellar initial mass function

We have analyzed Hubble Space Telescope NICMOS2 F110W-, F160W-, F165M-, and F207M-band images covering the central 1' × 1' region of the cluster associated with Mon R2 in order to constrain the initial mass function (IMF) down to 20M_J. The flux ratio between the F165M and F160W bands was used to measure the strength of the water-band absorption feature and select a sample of 12 out of the total sample of 181 objects that have effective temperatures between 2700 and 3300 K. These objects are placed in the H-R diagram together with sources observed by Carpenter et al. to estimate an age of ~1 Myr for the low-mass cluster population. By constructing extinction-limited samples, we are able to constrain the IMF and the fraction of stars with a circumstellar disk in a sample that is 90% complete for both high- and low-mass objects. For stars with estimated masses between 0.1 and 1.0 M_☉ for a 1 Myr population with A_V ≤ 19 mag, we find that 27% ± 9% have a near-infrared excess indicative of a circumstellar disk. The derived fraction is similar to or slightly lower than the fraction found in other star-forming regions of comparable age. We constrain the number of stars in the mass interval 0.08-1.0 M_☉ to the number of objects in the mass interval 0.02-0.08 M_☉ by forming the ratio R^(**) = N(0.08-1 M_☉)/N(0.02-0.08 M_☉) for objects in an extinction-limited sample complete for A_V ≤ 7 mag. The ratio is found to be R^(**) = 2.2 ± 1.3, assuming an age of 1 Myr, consistent with the similar ratio predicted by the system IMF proposed by Chabrier. The ratio is similar to the ratios observed toward the Orion Nebula Cluster and IC 348, as well as the ratio derived in the 28 deg^2 survey of Taurus by Guieu et al

Dietary elimination of children with food protein induced gastrointestinal allergy – micronutrient adequacy with and without a hypoallergenic formula?

Background: The cornerstone for management of Food protein-induced gastrointestinal allergy (FPGIA) is dietary exclusion; however the micronutrient intake of this population has been poorly studied. We set out to determine the dietary intake of children on an elimination diet for this food allergy and hypothesised that the type of elimination diet and the presence of a hypoallergenic formula (HF) significantly impacts on micronutrient intake. Method: A prospective observational study was conducted on children diagnosed with FPIGA on an exclusion diet who completed a 3 day semi-quantitative food diary 4 weeks after commencing the diet. Nutritional intake where HF was used was compared to those without HF, with or without a vitamin and mineral supplement (VMS). Results: One-hundred-and-five food diaries were included in the data analysis: 70 boys (66.7%) with median age of 21.8 months [IQR: 10 - 67.7]. Fifty-three children (50.5%) consumed a HF and the volume of consumption was correlated to micronutrient intake. Significantly (p <0.05) more children reached their micronutrient requirements if a HF was consumed. In those without a HF, some continued not to achieve requirements in particular for vitamin D and zinc, in spite of VMS. Conclusion: This study points towards the important micronutrient contribution of a HF in children with FPIGA. Children, who are not on a HF and without a VMS, are at increased risk of low intakes in particular vitamin D and zinc. Further studies need to be performed, to assess whether dietary intake translates into actual biological deficiencies

IN-SYNC. VIII. Primordial Disk Frequencies in NGC 1333, IC 348, and the Orion A Molecular Cloud

In this paper, we address two issues related to primordial disk evolution in three clusters (NGC 1333, IC 348, and Orion A) observed by the INfrared Spectra of Young Nebulous Clusters (IN-SYNC) project. First, in each cluster, averaged over the spread of age, we investigate how disk lifetime is dependent on stellar mass. The general relation in IC 348 and Orion A is that primordial disks around intermediate mass stars (2--5$M_{\odot}$) evolve faster than those around loss mass stars (0.1--1$M_{\odot}$), which is consistent with previous results. However, considering only low mass stars, we do not find a significant dependence of disk frequency on stellar mass. These results can help to better constrain theories on gas giant planet formation timescales. Secondly, in the Orion A molecular cloud, in the mass range of 0.35--0.7$M_{\odot}$, we provide the most robust evidence to date for disk evolution within a single cluster exhibiting modest age spread. By using surface gravity as an age indicator and employing 4.5 $\mu m$ excess as a primordial disk diagnostic, we observe a trend of decreasing disk frequency for older stars. The detection of intra-cluster disk evolution in NGC 1333 and IC 348 is tentative, since the slight decrease of disk frequency for older stars is a less than 1-$\sigma$ effect.Comment: 25 pages, 26 figures; submitted for publication (ApJ