Abstract
We report the joint WASP/KELT discovery of WASP-167b/KELT-13b, a transiting hot Jupiter with a 2.02-d orbit around a V = 10.5, F1V star with Fe/H = 0.1 ± 0.1. The 1.5 R
Jup planet was ...confirmed by Doppler tomography of the stellar line profiles during transit. We place a limit of <8 M
Jup on its mass. The planet is in a retrograde orbit with a sky-projected spin–orbit angle of λ = −165° ± 5°. This is in agreement with the known tendency for orbits around hotter stars to be more likely to be misaligned. WASP-167/KELT-13 is one of the few systems where the stellar rotation period is less than the planetary orbital period. We find evidence of non-radial stellar pulsations in the host star, making it a δ-Scuti or γ-Dor variable. The similarity to WASP-33, a previously known hot-Jupiter host with pulsations, adds to the suggestion that close-in planets might be able to excite stellar pulsations.
We demonstrate a straightforward implementation of a push-button like single-photon source, which is based on a strongly coupled atom-cavity system. The device operates intermittently for periods of ...up to 100μs, with single-photon repetition rates of 1.0MHz and an efficiency of 60%. Atoms are loaded into the cavity using an atomic fountain, with the upper turning point near the cavity's mode centre. This ensures long interaction times without any disturbances induced by trapping potentials. The latter is the key to reaching deterministic efficiencies as high as obtained in probabilistic photon-heralding schemes. The price to pay is the random loading of atoms into the cavity and the resulting intermittency. However, for all practical purposes, this has a negligible impact as an individual atom may emit up to 100 successive photons.
Reliable encoding of information in quantum systems is crucial to all approaches to quantum information processing or communication. This applies in particular to photons used in linear optics ...quantum computing, which is scalable provided a deterministic single-photon emission and preparation is available. Here, we show that narrowband photons deterministically emitted from an atom-cavity system fulfil these requirements. Within their 500 ns coherence time, we demonstrate a subdivision into d time bins of various amplitudes and phases, which we use for encoding arbitrary qu-d-its. The latter is done deterministically with a fidelity >95% for qubits, verified using a newly developed time-resolved quantum-homodyne method.
The Nainital-Cape Survey Joshi, S; Martinez, P; Chowdhury, S ...
Astronomy and astrophysics (Berlin),
06/2016, Letnik:
590
Journal Article
Recenzirano
Context. The Nainital-Cape Survey is a dedicated ongoing survey program to search for and study pulsational variability in chemically peculiar (CP) stars to understand their internal structure and ...evolution. Aims. The main aims of this survey are to find new pulsating Ap and Am stars in the northern and southern hemisphere and to perform asteroseismic studies of these new pulsators. Methods. The survey is conducted using high-speed photometry. The candidate stars were selected on the basis of having Stromgren photometric indices similar to those of known pulsating CP stars. Results. Over the last decade a total of 337 candidate pulsating CP stars were observed for the Nainital-Cape Survey, making it one of the longest ground-based surveys for pulsation in CP stars in terms of time span and sample size. The previous papers of this series presented seven new pulsating variables and 229 null results. In this paper we present the light curves, frequency spectra and various astrophysical parameters of the 108 additional CP stars observed since the last reported results. We also tabulated the basic physical parameters of the known roAp stars. As a part of establishing the detection limits in the Nainital-Cape Survey, we investigated the scintillation noise level at the two observing sites used in this survey, Sutherland and Nainital, by comparing the combined frequency spectra stars observed from each location. Our analysis shows that both the sites permit the detection of variations of the order of 0.6 milli-magnitude (mmag) in the frequency range 1-4 mHz, Sutherland is on average marginally better.
Recent whole-genome sequencing efforts led to the identification of IDH1(R132) mutations in acute myeloid leukemia (AML) patients. We studied the prevalence and clinical implications of IDH1 genomic ...alterations in pediatric and adult AML. Diagnostic DNA from 531 AML patients treated on Children's Oncology Group trial COG-AAML03P1 (N=257), and Southwest Oncology Group trials SWOG-9031, SWOG-9333 and SWOG-9500 (N=274), were tested for IDH1 mutations. Codon R132 mutations were absent in the pediatric cohort, but were found in 12 of 274 adult patients (4.4%, 95% CI 2.3-7.5). IDH1(R132) mutations occurred most commonly in patients with normal karyotype, and those with FLT3/ITD and NPMc mutations. Patients with IDH1(R132) mutations trended toward higher median diagnostic white blood cell counts (59.2 x 10(9) vs 29.1 x 10(9) per liter, P=0.19) than those without mutations, but the two groups did not differ significantly in age, bone marrow blast percentage, overall survival or relapse-free survival. Eleven patients (2.1%) harbored a novel V71I sequence alteration, which was found to be a germ-line polymorphism. IDH1 mutations were not detected in pediatric AML, and are uncommon in adult AML.
Through the use of Time-of-Flight Three Dimensional Polarimetric Neutron Tomography (ToF 3DPNT) we have for the first time successfully demonstrated a technique capable of measuring and ...reconstructing three dimensional magnetic field strengths and directions unobtrusively and non-destructively with the potential to probe the interior of bulk samples which is not amenable otherwise. Using a pioneering polarimetric set-up for ToF neutron instrumentation in combination with a newly developed tailored reconstruction algorithm, the magnetic field generated by a current carrying solenoid has been measured and reconstructed, thereby providing the proof-of-principle of a technique able to reveal hitherto unobtainable information on the magnetic fields in the bulk of materials and devices, due to a high degree of penetration into many materials, including metals, and the sensitivity of neutron polarisation to magnetic fields. The technique puts the potential of the ToF time structure of pulsed neutron sources to full use in order to optimise the recorded information quality and reduce measurement time.
Evaluation of transcriptional changes in the striatum may be an effective approach to understanding the natural history of changes in expression contributing to the pathogenesis of Huntington disease ...(HD). We have performed genome-wide expression profiling of the YAC128 transgenic mouse model of HD at 12 and 24 months of age using two platforms in parallel: Affymetrix and Illumina. The data from these two powerful platforms were integrated to create a combined rank list, thereby revealing the identity of additional genes that proved to be differentially expressed between YAC128 and control mice. Using this approach, we identified 13 genes to be differentially expressed between YAC128 and controls which were validated by quantitative real-time PCR in independent cohorts of animals. In addition, we analyzed additional time points relevant to disease pathology: 3, 6 and 9 months of age. Here we present data showing the evolution of changes in the expression of selected genes: Wt1, Pcdh20 and Actn2 RNA levels change as early as 3 months of age, whereas Gsg1l, Sfmbt2, Acy3, Polr2a and Ppp1r9a RNA expression levels are affected later, at 12 and 24 months of age. We also analyzed the expression of these 13 genes in human HD and control brain, thereby revealing changes in SLC45A3, PCDH20, ACTN2, DDAH1 and PPP1R9A RNA expression. Further study of these genes may unravel novel pathways contributing to HD pathogenesis. DDBJ/EMBL/GenBank accession no: GSE19677
ABSTRACT
V341 Ara was recently recognized as one of the closest (d ≃ 150 pc) and brightest (V ≃ 10) nova-like cataclysmic variables. This unique system is surrounded by a bright emission nebula, ...likely to be the remnant of a recent nova eruption. Embedded within this nebula is a prominent bow shock, where the system’s accretion disc wind runs into its own nova shell. In order to establish its fundamental properties, we present the first comprehensive multiwavelength study of the system. Long-term photometry reveals quasi-periodic, super-orbital variations with a characteristic time-scale of 10–16 d and typical amplitude of ≃1 mag. High-cadence photometry from theTransiting Exoplanet Survey Satellite (TESS) reveals for the first time both the orbital period and a ‘negative superhump’ period. The latter is usually interpreted as the signature of a tilted accretion disc. We propose a recently developed disc instability model as a plausible explanation for the photometric behaviour. In our spectroscopic data, we clearly detect antiphased absorption and emission-line components. Their radial velocities suggest a high mass ratio, which in turn implies an unusually low white-dwarf mass. We also constrain the wind mass-loss rate of the system from the spatially resolved O iii emission produced in the bow shock; this can be used to test and calibrate accretion disc wind models. We suggest a possible association between V341 Ara and a ‘guest star’ mentioned in Chinese historical records in AD 1240. If this marks the date of the system’s nova eruption, V341 Ara would be the oldest recovered nova of its class and an excellent laboratory for testing nova theory.
We report periods for 33 members of Blanco 1 as measured from Kilodegree Extremely Little Telescope-South light curves, the first reported rotation periods for this benchmark zero-age-main-sequence ...open cluster. The distribution of these stars spans from late-A or early-F dwarfs tomid-K with periods ranging from less than a day to ~8 days. The rotation period distribution has a morphology similar to the coeval Pleiades cluster, suggesting the universal nature of stellar rotation distributions. Employing two different gyrochronology methods, we find an age of 146 super(+13) sub(-14) Myr for the cluster. We find the Skumanich-like spin-down rate sufficiently describes the rotation evolution of stars hotter than the Sun; however, we find cooler stars rotating faster than predicted by a Skumanich law, suggesting a mass dependence in the efficiency of stellar angular momentum loss rate. Finally, we compare the Blanco 1 and Pleiades rotation period distributions to available nonlinear angular momentum evolution models.
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