The primordial deuterium abundance at z = 2.504 from a high signal-to-noise spectrum of Q1009+2956

The spectrum of the $z_{\rm em} = 2.63$ quasar Q1009+2956 has been observed extensively on the Keck telescope. The Lyman limit absorption system $z_{\rm abs} = 2.504$ was previously used to measure D/H by Burles & Tytler using a spectrum with signal to noise approximately 60 per pixel in the continuum near Ly {\alpha} at $z_{\rm abs} = 2.504$. The larger dataset now available combines to form an exceptionally high signal to noise spectrum, around 147 per pixel. Several heavy element absorption lines are detected in this LLS, providing strong constraints on the kinematic structure. We explore a suite of absorption system models and find that the deuterium feature is likely to be contaminated by weak interloping Ly {\alpha} absorption from a low column density H I cloud, reducing the expected D/H precision. We find D/H = $2.48^{+0.41}_{-0.35}\times10^{-5}$ for this system. Combining this new measurement with others from the literature and applying the method of Least Trimmed Squares to a statistical sample of 15 D/H measurements results in a "reliable" sample of 13 values. This sample yields a primordial deuterium abundance of (D/H)$_{\rm p} = (2.545 \pm 0.025)\times10^{-5}$. The corresponding mean baryonic density of the Universe is $\Omega_{\rm b}h^2 = 0.02174\pm0.00025$. The quasar absorption data is of the same precision as, and marginally inconsistent with, the 2015 CMB Planck (TT+lowP+lensing) measurement, $\Omega_{\rm b}h^2 = 0.02226\pm0.00023$. Further quasar and more precise nuclear data are required to establish whether this is a random fluctuation.Comment: accepted by MNRAS, 18 pages, 12 figures, 6 table

Application of digital analysis of MSS data to agro-environmental studies

There are no author-identified significant results in this report

Gypsy moths and American dog ticks: Space partners

An experiment intended for the space shuttle and designed to investigate the effects of weightlessness and total darkness on gypsy moth eggs and engorged American dog ticks is described. The objectives are: (1) to reevaluate the effects of zero gravity on the termination of diapause/hibernation of embryonated gypsy moth eggs, (2) to determine the effect of zero gravity on the ovipositions and subsequent hatch from engorged female American dog ticks that have been induced to diapause in the laboratory, and (3) to determine whether morphological or biochemical changes occur in the insects under examination. Results will be compared with those from a similar experiment conducted on Skylab 4

Application of digital analysis of MSS data to agro-environmental studies

There are no author-identified significant results in this report

Reports Of Conferences, Institutes, And Seminars

This quarter\u27s column offers coverage of multiple sessions from the 2016 Electronic Resources & Libraries (ER&L) Conference, held April 3–6, 2016, in Austin, Texas. Topics in serials acquisitions dominate the column, including reports on altmetrics, cost per use, demand-driven acquisitions, and scholarly communications and the use of subscriptions agents; ERMS, access, and knowledgebases are also featured

Orchard Machine

A general purpose, self-propelled, orchard machine has a rectangular vertical frame mounted on driven and steerable wheels with the machine straddling fruit trees and supporting an operator who, through a single hydraulic system, controls the movements of the machine and the operation of the arrangements carried thereby. The frame has collapsible front and rear sections whereby the width thereof is reduced for travel on public roadways and also has opposing side sections that support laterally inwardly and outwardly movable fruit catching sections disposed adjacent the bottom of the machine which carries an overlying tree shaker. Such catching sections have caster wheels and are moved apart as the machine straddles a tree and brought together to encircle the tree and catch the falling fruit which is transported rearwardly and then laterally of the machine by conveyors associated with the catching sections. In spraying, trimming or otherwise treating fruit trees, the catching sections are removed and the frame sections carry appropriate spraying, cutting and other arrangements

Ground-state cooling of a trapped ion Using long-wavelength radiation

We demonstrate ground-state cooling of a trapped ion using radio-frequency (rf) radiation. This is a powerful tool for the implementation of quantum operations, where rf or microwave radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of n¯=0.13(4) after sideband cooling, corresponding to a ground-state occupation probability of 88(7)%. After preparing in the vibrational ground state, we demonstrate motional state engineering by driving Rabi oscillations between the |n=0⟩ and |n=1⟩ Fock states. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost 2 orders of magnitude compared with our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system