Polymediated Narrative: The Case of the Supernatural Episode Fan Fiction

Modern stories are the product of a recursive process influenced by elements of genre, outside content, medium, and more. These stories exist in a multitude of forms and are transmitted across multiple media. This article examines how those stories function as pieces of a broader narrative, as well as how that narrative acts as a world for the creation of stories. Through an examination of the polymediated nature of modern narratives, we explore the complicated nature of modern storytelling

Observation of Feshbach-like resonances in collisions between ultracold molecules

We observe magnetically tuned collision resonances for ultracold Cs2 molecules stored in a CO2-laser trap. By magnetically levitating the molecules against gravity, we precisely measure their magnetic moment. We find an avoided level crossing which allows us to transfer the molecules into another state. In the new state, two Feshbach-like collision resonances show up as strong inelastic loss features. We interpret these resonances as being induced by Cs4 bound states near the molecular scattering continuum. The tunability of the interactions between molecules opens up novel applications such as controlled chemical reactions and synthesis of ultracold complex molecules

Deep learning of spatial densities in inhomogeneous correlated quantum systems

Machine learning has made important headway in helping to improve the treatment of quantum many-body systems. A domain of particular relevance are correlated inhomogeneous systems. What has been missing so far is a general, scalable deep-learning approach that would enable the rapid prediction of spatial densities for strongly correlated systems in arbitrary potentials. In this work, we present a straightforward scheme, where we learn to predict densities using convolutional neural networks trained on random potentials. While we demonstrate this approach in 1D and 2D lattice models using data from numerical techniques like Quantum Monte Carlo, it is directly applicable as well to training data obtained from experimental quantum simulators. We train networks that can predict the densities of multiple observables simultaneously and that can predict for a whole class of many-body lattice models, for arbitrary system sizes. We show that our approach can handle well the interplay of interference and interactions and the behaviour of models with phase transitions in inhomogeneous situations, and we also illustrate the ability to solve inverse problems, finding a potential for a desired density

Pre-Main Sequence variables in the VMR-D : identification of T Tauri-like accreting protostars through Spitzer-IRAC variability

We present a study of the infrared variability of young stellar objects by means of two Spitzer-IRAC images of the Vela Molecular Cloud D (VMR-D) obtained in observations separated in time by about six months. By using the same space-born IR instrumentation, this study eliminates all the unwanted effects usually unavoidable when comparing catalogs obtained from different instruments. The VMR-D map covers about 1.5 square deg. of a site where star formation is actively ongoing. We are interested in accreting pre-main sequence variables whose luminosity variations are due to intermittent events of disk accretion (i.e. active T Tauri stars and EXor type objects). The variable objects have been selected from a catalog of more than 170,000 sources detected at a S/N ratio > 5. We searched the sample of variables for ones whose photometric properties are close to those of known EXor's. These latter are monitored in a more systematic way than T Tauri stars and the mechanisms that regulate the observed phenomenology are exactly the same. Hence the modalities of the EXor behavior is adopted as driving criterium for selecting variables in general. We selected 19 bona fide candidates that constitute a well-defined sample of new variable targets for further investigation. Out of these, 10 sources present a Spitzer MIPS 24 micron counterpart, and have been classified as 3 Class I, 5 flat spectrum and 2 Class II objects, while the other 9 sources have spectral energy distribution compatible with phases older than Class I. This is consistent with what is known about the small sample of known EXor's, and suggests that the accretion flaring or EXor stage might come as a Class I/II transition. We present also new prescriptions that can be useful in future searches for accretion variables in large IR databases.Comment: 35 pages, 12 figures To appear in Ap

Fundamental Vibrational Transition of CO During the Outburst of EX Lupi in 2008

We report monitoring observations of the T Tauri star EX Lupi during its outburst in 2008 in the CO fundamental band at 4.6–5.0 μm. The observations were carried out at the Very Large Telescope and the Subaru Telescope at six epochs from 2008 April to August, covering the plateau of the outburst and the fading phase to a quiescent state. The line flux of CO emission declines with the visual brightness of the star and the continuum flux at 5 μm, but composed of two subcomponents that decay with different rates. The narrow-line emission (50 kms^(−1) in FWHM) is near the systemic velocity of EX Lupi. These emission lines appear exclusively in v =1–0. The line widths translate to a characteristic orbiting radius of 0.4 AU. The broad-line component (FWZI ~ 150 km s^(−1)) is highly excited up to v ≤ 6. The line flux of the component decreases faster than the narrow-line emission. Simple modeling of the line profiles implies that the broad-line emitting gas is orbiting around the star at 0.04–0.4 AU. The excitation state, the decay speed of the line flux, and the line profile indicate that the broad-line emission component is physically distinct from the narrow-line emission component, and more tightly related to the outburst event

Centrosymmetric molecules as possible carriers of diffuse interstellar bands

In this paper, we present new data with interstellar C2 (Phillips bands A-X), from observations made with the Ultraviolet-Visual Echelle Spectrograph of the European Southern Observatory. We have determined the interstellar column densities and excitation temperatures of C2 for nine Galactic lines. For seven of these, C2 has never been observed before, so in this case the still small sample of interstellar clouds (26 lines of sight), where a detailed analysis of C2 excitation has been made, has increased significantly. This paper is a continuation of previous works where interstellar molecules (C2 and diffuse interstellar bands) have been analysed. Because the sample of interstellar clouds with C2 has increased, we can show that the width and shape of the profiles of some diffuse interstellar bands (6196 and 5797 A) apparently depend on the gas kinetic and rotational temperatures of C2; the profiles are broader because of the higher values of the gas kinetic and rotational temperatures of C2. There are also diffuse interstellar bands (4964 and 5850 A) for which this effect does not exist.Comment: 8 pages, 4 figures, accepted to MNRAS 201

Testing the Relation Between the Local and Cosmic Star Formation Histories

Recently, there has been great progress toward observationally determining the mean star formation history of the universe. When accurately known, the cosmic star formation rate could provide much information about Galactic evolution, if the Milky Way's star formation rate is representative of the average cosmic star formation history. A simple hypothesis is that our local star formation rate is proportional to the cosmic mean. In addition, to specify a star formation history, one must also adopt an initial mass function (IMF); typically it is assumed that the IMF is a smooth function which is constant in time. We show how to test directly the compatibility of all these assumptions, by making use of the local (solar neighborhood) star formation record encoded in the present-day stellar mass function. Present data suggests that at least one of the following is false: (1) the local IMF is constant in time; (2) the local IMF is a smooth (unimodal) function; and/or (3) star formation in the Galactic disk was representative of the cosmic mean. We briefly discuss how to determine which of these assumptions fail, and improvements in observations which will sharpen this test.Comment: 14 pages in LaTeX (uses aaspp4.sty). 5 postscript figures. To appear in the Astrophysical Journa

Very Low Mass Stars and Brown Dwarfs in Taurus-Auriga

We present high resolution optical spectra obtained with the HIRES spectrograph on the Keck I telescope of low mass T Tauri stars and brown dwarfs (LMTTs) in Taurus-Auriga. Of particular interest is the previously classified "continuum T Tauri star" GM Tau, which has a spectral type of M6.5 and a mass just below the stellar/substellar boundary. None of the LMTTs in Taurus are rapidly rotating (vsini < 30 km/s), unlike low mass objects in Orion. Many of the slowly rotating, non-accreting stars and brown dwarfs exhibit prominent H-alpha emission (EWs of 3 - 36 A), indicative of active chromospheres. We demonstrate empirically that the full-width at 10% of the H-alpha emission profile peak is a more practical and possibly more accurate indicator of accretion than either the equivalent width of H-alpha or optical veiling: 10%-widths > 270 km/s are classical T Tauri stars (i.e. accreting), independent of stellar spectral type. Although LMTTs can have accretion rates comparable to that of more typical, higher-mass T Tauri stars (e.g. K7-M0), the average mass accretion rate appears to decrease with decreasing mass. The diminished frequency of accretion disks for LMTTs, in conjunction with their lower, on average, mass accretion rates, implies that they are formed with less massive disks than higher-mass T Tauri stars. The radial velocities, circumstellar properties and known binaries do not support the suggestion that many of the lowest mass members of Taurus have been ejected from higher stellar density regions within the cloud. Instead, LMTTs appear to have formed and are evolving in the same way as higher-mass T Tauri stars, but with smaller disks and shorter disk lifetimes.Comment: 27 pages, plus 8 figures, accepted for publication in Ap

HOPS: Automated detection and authentication of pathogen DNA in archaeological remains

High-throughput DNA sequencing enables large-scale metagenomic analyses of complex biological systems. Such analyses are not restricted to present day environmental or clinical samples, but can also be fruitfully applied to molecular data from archaeological remains (ancient DNA), and a focus on ancient bacteria can provide valuable information on the long-term evolutionary relationship between hosts and their pathogens. Here we present HOPS (Heuristic Operations for Pathogen Screening), an automated bacterial screening pipeline for ancient DNA sequence data that provides straightforward and reproducible information on species identification and authenticity. HOPS provides a versatile and fast pipeline for high-throughput screening of bacterial DNA from archaeological material to identify candidates for subsequent genomic-level analyses