First results from the UHRF: ultra-high-resolution observations of atomic interstellar lines towards ζ Ophiuchi

We present ultra-high-resolution observations of optical interstellar lines towards ζOph obtained during the commissioning phase of the new Ultra-High-Resolution Facility (UHRF) at the AAT. The UHRF has achieved its design resolving power of R≈106, and has very clearly resolved hyperfine splitting in three of the 11 identified Na I D-line velocity components towards ζ Oph. In addition, the intrinsic line profiles of the 3s-4p Na I doublet at 3302 Å have been measured for the first time. 12 velocity components are identified in the interstellar Ca II K-line absorption profile, of which seven have definite velocity counterparts in the Na I profile. Three of the Na I velocity components have b-values which correspond to a gas temperature of about 200 K, for the case of pure thermal broadening. The strongest component in the sightline (-14.8 km s-1) was found to have a b-value of 0.6+0.2−0.1kms−1⁠, corresponding to a temperature of 500 K. If a true gas kinetic temperature of 54 K is assumed to apply to this component, from the H2 rotational excitation temperature previously measured for the ζ Oph sightline, then the observed Na I and Fe I line profiles both imply an rms turbulent velocity of 0.4 km s-1 within the cloud, just less than the local sound speed. The observed Ca II linewidths are all significantly larger than those of the corresponding Na I components. The Ca IIcomponents are interpreted as arising from warm neutral material (intercloud medium) surrounding cooler clouds, while half of the Na I components arise from cool clouds and half arise from warm intercloud material. The measured Na I/CaII column density ratios, and the inferred temperatures, are consistent with a model in which calcium is heavily depleted on to grains in cool clouds but is restored to the gas phase by impact desorption in the warm intercloud medium

The ultra-high-resolution facility at the Anglo-Australian telescope

The Ultra-High-Resolution Facility (UHRF) has been commissioned at the coudé focus of the Anglo-Australian Telescope (AAT), and provides a resolving power of R≈106. This is the highest spectral resolution ever obtained by an optical astronomical spectrograph, and is intended mainly for astrophysical studies of cool interstellar clouds. This paper describes the development of this ambitious project, which includes diffraction-limited optical components, very tight specification for the optical configuration, and a new type of image slicer which allows ultra-high-resolution work towards faint stars. Astrophysical results from the first observing runs are presented to demonstrate the performance in terms of both resolution and throughput

Magnetoluminescence

Pulsar Wind Nebulae, Blazars, Gamma Ray Bursts and Magnetars all contain regions where the electromagnetic energy density greatly exceeds the plasma energy density. These sources exhibit dramatic flaring activity where the electromagnetic energy distributed over large volumes, appears to be converted efficiently into high energy particles and gamma-rays. We call this general process magnetoluminescence. Global requirements on the underlying, extreme particle acceleration processes are described and the likely importance of relativistic beaming in enhancing the observed radiation from a flare is emphasized. Recent research on fluid descriptions of unstable electromagnetic configurations are summarized and progress on the associated kinetic simulations that are needed to account for the acceleration and radiation is discussed. Future observational, simulation and experimental opportunities are briefly summarized.Comment: To appear in "Jets and Winds in Pulsar Wind Nebulae, Gamma-ray Bursts and Blazars: Physics of Extreme Energy Release" of the Space Science Reviews serie

Core outcome set for clinical studies of postoperative ileus after intestinal surgery

Postoperative ileus is a common and distressing complication after intestinal surgery. . It presents clinically as impairment of intestinal motility, characterized by abdominal pain, vomiting, and delayed recovery of defaecatory function. For patients, this increases the risk of serious complications, such as pneumonia, venous thromboembolic events, and malnutrition . For healthcare systems, it leads to a substantial economic burden associated with increased medical, nursing, dietitian, and laboratory costs . Accordingly, postoperative ileus is now recognized as a research priority by expert and public stakeholder groups . Numerous clinical interventions have been evaluated in efforts to prevent postoperative ileus, but few have led to meaningful patient benefit . A key challenge for researchers is the absence of a standardized and agreed framework to describe the effectiveness of new interventions in clinical studies . Common outcomes include the time taken until first passage of flatus/stool, time until tolerance of oral diet, and the return of bowel sounds. It remains unclear, however, whether these are sufficiently relevant to patients and healthcare professionals when evaluating new treatments and implementing them in clinical practice . A solution to this problem is the development of an agreed core outcome set developed through patient–clinician consensus. Core outcome sets provide a minimum set of outcomes that should be reported in all studies of a defined clinical condition and are supported by the Core Outcome Measures in Effective Trials (COMET) Initiative . The present report describes the international development and final content of an agreed core outcome set for postoperative ileus relevant to patients undergoing intestinal surgery.S.J. Chapman ... H. Kroon ... T. Sammour ... J. Han ... Tripartite Gastrointestinal Recovery Post-operative IIeus Group ... et al