Laser damage database at 1064 nm

In conjunction with our diversification of laser damage testing capabilities, we have expanded upon a database of threshold measurements and parameter variations at 1064 nm. This includes all tests at low pulse-repetition frequencies (PRF) ranging from single shots to 120 Hz. These tests were conducted on the Reptile laser facility since 1987 and the Variable Pulse Laser (VPL) facility since 1988. Pulse durations ranged from 1 to 16 ns. 10 refs., 14 figs

Studies of Neutron Stars at Optical/IR Wavelengths

In the last years, optical studies of Isolated Neutron Stars (INSs) have expanded from the more classical rotation-powered ones to other categories, like the Anomalous X-ray Pulsars (AXPs) and the Soft Gamma-ray Repeaters (SGRs), which make up the class of the magnetars, the radio-quiet INSs with X-ray thermal emission and, more recently, the enigmatic Compact Central Objects (CCOs) in supernova remnants. Apart from 10 rotation-powered pulsars, so far optical/IR counterparts have been found for 5 magnetars and for 4 INSs. In this work we present some of the latest observational results obtained from optical/IR observations of different types of INSs

Avances en el estudio de las bases genéticas y organolépticas del cacao fino o de aroma en el Perú

Las variedades de cacao fino o de aroma en el Perú son utilizados para elaborar los mejores chocolates del mundo por sus exquisitas y poco comunes características organolépticas, Estas características permiten que el cacao peruano gane reconocimiento internacional y de ahí su gran valor económico. A pesar de esto, poco se sabe sobre los componentes genéticos y/o ambientales que contribuyen a la exclusividad de este valioso recurso económico. En el proyecto de investigación aplicada: “Estudio molecular de la diversidad genética de los cacaos aromáticos en el Perú con fines del fortalecimiento de su competitividad y aumento de la producción nacional de cacao de calidad”, financiado por Innóvate Perú del Ministerio de la Producción, se tiene como objetivos determinar la variabilidad genética y caracterización organoléptica de más de 100 tipos de cacao fino o de aroma que se cultivan a lo largo de las cinco principales regiones del Perú (Amazonas, Cusco, San Martin, Piura y Huánuco). Adicionalmente, la Universidad Nacional Agraria de la Selva en Tingo María y el Instituto de Investigaciones de la Amazonia Peruana en Tarapoto, hospedarán bancos de germoplasma y de propagación de esquejes para la difusión y estudios de estos valiosos recursos. Hasta inicios del 2017, ya se han recolectado más de 80 genotipos provenientes de las cinco regiones. Protocolos para análisis sensoriales que cumplan los más rigurosos estándares internacionales se han venido estableciendo. Por otro lado, técnicas de marcadores moleculares usando marcadores de DNA tipo SSR y SNPs, seguido por secuenciamiento de ADN, se vienen estableciendo. Estudios de asociación de fenotipo-genotipo formarán parte del conocimiento generado en este proyecto. Adicionalmente, estos conocimientos permitirán generar información genómica valiosa para salvaguardar nuestra biodiversidad nativa, otorgándole a los productores y sus asociaciones de herramientas para proteger sus recursos genéticos y a los potenciales mejoradores de cacao más luces en cuanto a la asociación genotipo-calidad. Se espera que a fin del proyecto, se cuente con los resultados de genotipificación de más de 100 genotipos de cacao fino o de aroma y mediante el resecuenciamiento se revelen SNPs particulares para cada grupo genético en cada región muestreada

The TESS-Keck Survey. II. An Ultra-Short-Period Rocky Planet And Its Siblings Transiting The Galactic Thick-Disk Star TOI-561

We report the discovery of TOI-561, a multiplanet system in the galactic thick disk that contains a rocky, ultra-short-period planet. This bright (V = 10.2) star hosts three small transiting planets identified in photometry from the NASA TESS mission: TOI-561 b (TOI-561.02, P = 0.44 days, Rp = 1.45 ± 0.11 R⊕), c (TOI-561.01, P = 10.8 days, Rp = 2.90 ± 0.13 R⊕), and d (TOI-561.03, P = 16.3 days, Rp = 2.32 ± 0.16 R⊕). The star is chemically ([Fe/H] = −0.41 ± 0.05, [α/Fe] = +0.23 ± 0.05) and kinematically consistent with the galactic thick-disk population, making TOI-561 one of the oldest (10 ± 3 Gyr) and most metal-poor planetary systems discovered yet. We dynamically confirm planets b and c with radial velocities from the W. M. Keck Observatory High Resolution Echelle Spectrometer. Planet b has a mass and density of 3.2 ± 0.8 M⊕ and ${5.5}_{-1.6}^{+2.0}$g cm−3, consistent with a rocky composition. Its lower-than-average density is consistent with an iron-poor composition, although an Earth-like iron-to-silicates ratio is not ruled out. Planet c is 7.0 ± 2.3 M⊕ and 1.6 ± 0.6 g cm−3, consistent with an interior rocky core overlaid with a low-mass volatile envelope. Several attributes of the photometry for planet d (which we did not detect dynamically) complicate the analysis, but we vet the planet with high-contrast imaging, ground-based photometric follow-up, and radial velocities. TOI-561 b is the first rocky world around a galactic thick-disk star confirmed with radial velocities and one of the best rocky planets for thermal emission studies

Limit on Bs0B^0_s oscillation using a jet charge method

A lower limit is set on the B_{s}^{0} meson oscillation parameter \Delta m_{s} using data collected from 1991 to 1994 by the ALEPH detector. Events with a high transverse momentum lepton and a reconstructed secondary vertex are used. The high transverse momentum leptons are produced mainly by b hadron decays, and the sign of the lepton indicates the particle/antiparticle final state in decays of neutral B mesons. The initial state is determined by a jet charge technique using both sides of the event. A maximum likelihood method is used to set a lower limit of \, \Delta m_{s}. The 95\% confidence level lower limit on \Delta m_s ranges between 5.2 and 6.5(\hbar/c^{2})~ps^{-1} when the fraction of b quarks from Z^0 decays that form B_{s}^{0} mesons is varied from 8\% to 16\%. Assuming that the B_{s}^{0} fraction is 12\%, the lower limit would be \Delta m_{s} 6.1(\hbar/c^{2})~ps^{-1} at 95\% confidence level. For x_s = \Delta m_s \, \tau_{B_s}, this limit also gives x_s 8.8 using the B_{s}^{0} lifetime of \tau_{B_s} = 1.55 \pm 0.11~ps and shifting the central value of \tau_{B_s} down by 1\sigma

Measurement of the Bs0^0_s lifetime and production rate with Ds−l+^-_s l^+ combinations in Z decays

The lifetime of the \bs meson is measured in approximately 3 million hadronic Z decays accumulated using the ALEPH detector at LEP from 1991 to 1994. Seven different \ds decay modes were reconstructed and combined with an opposite sign lepton as evidence of semileptonic \bs decays. Two hundred and eight \dsl candidates satisfy selection criteria designed to ensure precise proper time reconstruction and yield a measured \bs lifetime of \mbox{\result .} Using a larger, less constrained sample of events, the product branching ratio is measured to be \mbox{\pbrresult