Impact and effectiveness of mRNA BNT162b2 vaccine against SARS-CoV-2 infections and COVID-19 cases, hospitalisations, and deaths following a nationwide vaccination campaign in Israel: an observational study using national surveillance data.

BACKGROUND: Following the emergency use authorisation of the Pfizer-BioNTech mRNA COVID-19 vaccine BNT162b2 (international non-proprietary name tozinameran) in Israel, the Ministry of Health (MoH) launched a campaign to immunise the 6·5 million residents of Israel aged 16 years and older. We estimated the real-world effectiveness of two doses of BNT162b2 against a range of SARS-CoV-2 outcomes and to evaluate the nationwide public-health impact following the widespread introduction of the vaccine. METHODS: We used national surveillance data from the first 4 months of the nationwide vaccination campaign to ascertain incident cases of laboratory-confirmed SARS-CoV-2 infections and outcomes, as well as vaccine uptake in residents of Israel aged 16 years and older. Vaccine effectiveness against SARS-CoV-2 outcomes (asymptomatic infection, symptomatic infection, and COVID-19-related hospitalisation, severe or critical hospitalisation, and death) was calculated on the basis of incidence rates in fully vaccinated individuals (defined as those for whom 7 days had passed since receiving the second dose of vaccine) compared with rates in unvaccinated individuals (who had not received any doses of the vaccine), with use of a negative binomial regression model adjusted for age group (16-24, 25-34, 35-44, 45-54, 55-64, 65-74, 75-84, and ≥85 years), sex, and calendar week. The proportion of spike gene target failures on PCR test among a nationwide convenience-sample of SARS-CoV-2-positive specimens was used to estimate the prevelance of the B.1.1.7 variant. FINDINGS: During the analysis period (Jan 24 to April 3, 2021), there were 232 268 SARS-CoV-2 infections, 7694 COVID-19 hospitalisations, 4481 severe or critical COVID-19 hospitalisations, and 1113 COVID-19 deaths in people aged 16 years or older. By April 3, 2021, 4 714 932 (72·1%) of 6 538 911 people aged 16 years and older were fully vaccinated with two doses of BNT162b2. Adjusted estimates of vaccine effectiveness at 7 days or longer after the second dose were 95·3% (95% CI 94·9-95·7; incidence rate 91·5 per 100 000 person-days in unvaccinated vs 3·1 per 100 000 person-days in fully vaccinated individuals) against SARS-CoV-2 infection, 91·5% (90·7-92·2; 40·9 vs 1·8 per 100 000 person-days) against asymptomatic SARS-CoV-2 infection, 97·0% (96·7-97·2; 32·5 vs 0·8 per 100 000 person-days) against symptomatic COVID-19, 97·2% (96·8-97·5; 4·6 vs 0·3 per 100 000 person-days) against COVID-19-related hospitalisation, 97·5% (97·1-97·8; 2·7 vs 0·2 per 100 000 person-days) against severe or critical COVID-19-related hospitalisation, and 96·7% (96·0-97·3; 0·6 vs 0·1 per 100 000 person-days) against COVID-19-related death. In all age groups, as vaccine coverage increased, the incidence of SARS-CoV-2 outcomes declined. 8006 of 8472 samples tested showed a spike gene target failure, giving an estimated prevalence of the B.1.1.7 variant of 94·5% among SARS-CoV-2 infections. INTERPRETATION: Two doses of BNT162b2 are highly effective across all age groups (≥16 years, including older adults aged ≥85 years) in preventing symptomatic and asymptomatic SARS-CoV-2 infections and COVID-19-related hospitalisations, severe disease, and death, including those caused by the B.1.1.7 SARS-CoV-2 variant. There were marked and sustained declines in SARS-CoV-2 incidence corresponding to increasing vaccine coverage. These findings suggest that COVID-19 vaccination can help to control the pandemic. FUNDING: None.

Homogeneous, Micron-Scale High-Energy-Density Matter Generated by Relativistic Laser-Solid Interactions.

Short-pulse, laser-solid interactions provide a unique platform for studying complex high-energy-density matter. We present the first demonstration of solid-density, micron-scale keV plasmas uniformly heated by a high-contrast, 400 nm wavelength laser at intensities up to 2×10^{21} W/cm^{2}. High-resolution spectral analysis of x-ray emission reveals uniform heating up to 3.0 keV over 1 µm depths. Particle-in-cell simulations indicate the production of a uniformly heated keV plasma to depths of 2 µm. The significant bulk heating and presence of highly ionized ions deep within the target are attributed to the few MeV hot electrons that become trapped and undergo refluxing within the target sheath fields. These conditions enabled the differentiation of atomic physics models of ionization potential depression in high-energy-density environments.

Randomized Trial of Pleural Fluid Drainage Frequency in Patients with Malignant Pleural Effusions. The ASAP Trial.

RATIONALE: Patients with malignant pleural effusions have significant dyspnea and shortened life expectancy. Indwelling pleural catheters allow patients to drain pleural fluid at home and can lead to autopleurodesis. The optimal drainage frequency to achieve autopleurodesis and freedom from catheter has not been determined. OBJECTIVES: To determine whether an aggressive daily drainage strategy is superior to the current standard every other day drainage of pleural fluid in achieving autopleurodesis. METHODS: Patients were randomized to either an aggressive drainage (daily drainage; n = 73) or standard drainage (every other day drainage; n = 76) of pleural fluid via a tunneled pleural catheter. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the incidence of autopleurodesis following the placement of the indwelling pleural catheters. The rate of autopleurodesis, defined as complete or partial response based on symptomatic and radiographic changes, was greater in the aggressive drainage arm than the standard drainage arm (47% vs. 24%, respectively; P = 0.003). Median time to autopleurodesis was shorter in the aggressive arm (54 d; 95% confidence interval, 34-83) as compared with the standard arm (90 d; 95% confidence interval, 70 to nonestimable). Rate of adverse events, quality of life, and patient satisfaction were not significantly different between the two arms. CONCLUSIONS: Among patients with malignant pleural effusion, daily drainage of pleural fluid via an indwelling pleural catheter led to a higher rate of autopleurodesis and faster time to liberty from catheter. Clinical trial registered with www.clinicaltrials.gov (NCT 00978939).

Palliative interventional pulmonology procedures in the incarcerated population with cancer: a case series.

RATIONALE: Cancer is the second most common cause of death in incarcerated population and lung cancer is the most common cause of cancer death in this group. Inmates are excluded from most published surveys and research,thus the effectiveness of lung cancer palliation in this population is not known. OBJECTIVE: To report the feasibility and safety of palliative interventional pulmonary procedures in inmates with cancer. STUDY DESIGN: Retrospective review of registry data from a single center. MATERIALS AND METHODS: Inmate data on prospectively enrolled data registry (2009­2012) from the interventional pulmonology procedural registry at Virginia Commonwealth University was extracted and analyzed for safety and efficacy. Inmates with lung cancer and advanced malignancies with pleural or airway metastasis requiring airway debulking (mechanical/thermal), airway stenting, and tunneled pleural catheter (TPC) placement were included in the analysis. RESULTS: A total of 16 procedures were performed in 12 incarcerated patients. These included six TPC placements in six patients. Ten procedures were performed in seven patients with airway obstruction. These procedures included rigid and flexible bronchoscopy with mechanical (rigid and balloon dilation) and thermal (laser, argon plasma coagulation, and cautery) tumor debulking and dilation,airway stenting, and tracheostomy in one case. All six TPCpatients had immediate symptomatic relief and improved lung aeration on chest radiograph. Three of six patients had successful auto-pleurodesis. In the seven patients with airway obstruction, three patients reported symptomatic relief and one had resolution of post-obstructive pneumonia. No immediate- or long-term procedure-related complications were reported. CONCLUSION: Incarcerated patients with advanced malignancy may benefit from interventional pulmonology procedures with low complications. Palliative interventional pulmonology procedures in inmates should not be withheld solely on their incarceration status.

Charge equilibrium of a laser-generated carbon-ion beam in warm dense matter.

Using ion carbon beams generated by high intensity short pulse lasers we perform measurements of single shot mean charge equilibration in cold or isochorically heated solid density aluminum matter. We demonstrate that plasma effects in such matter heated up to 1 eV do not significantly impact the equilibration of carbon ions with energies 0.045-0.5 MeV/nucleon. Furthermore, these measurements allow for a first evaluation of semiempirical formulas or ab initio models that are being used to predict the mean of the equilibrium charge state distribution for light ions passing through warm dense matter.

Observations of the effect of ionization-potential depression in hot dense plasma.

The newly commissioned Orion laser system has been used to study dense plasmas created by a combination of short pulse laser heating and compression by laser driven shocks. Thus the plasma density was systematically varied between 1 and 10 g/cc by using aluminum samples buried in plastic foils or diamond sheets. The aluminum was heated to electron temperatures between 500 and 700 eV allowing the plasma conditions to be diagnosed by K-shell emission spectroscopy. The K-shell spectra show the effect of the ionization potential depression as a function of density. The data are compared to simulated spectra which account for the change in the ionization potential by the commonly used Stewart and Pyatt prescription and an alternative due to Ecker and Kröll suggested by recent x-ray free-electron laser experiments. The experimental data are in closer agreement with simulations using the model of Stewart and Pyatt.

Artificial neural network is highly predictive of outcome in paediatric acute liver failure.

Current prognostic models in PALF are unreliable, failing to account for complex, non-linear relationships existing between multiple prognostic factors. A computational approach using ANN should provide superior modelling to PELD-MELD scores. We assessed the prognostic accuracy of PELD-MELD scores and ANN in PALF in children presenting to the QLTS, Australia. A comprehensive registry-based data set was evaluated in 54 children (32M, 22F, median age 17 month) with PALF. PELD-MELD scores calculated at (i) meeting PALF criteria and (ii) peak. ANN was evaluated using stratified 10-fold cross-validation. Outcomes were classified as good (transplant-free survival) or poor (death or LT) and predictive accuracy compared using AUROC curves. Mean PELD-MELD scores were significantly higher in non-transplanted non-survivors (i) 37 and (ii) 46 and transplant recipients (i) 32 and (ii) 43 compared to transplant-free survivors (i) 26 and (ii) 30. Threshold PELD-MELD scores ≥27 and ≥42, at meeting PALF criteria and peak, gave AUROC 0.71 and 0.86, respectively, for poor outcome. ANN showed superior prediction for poor outcome with AUROC 0.96, sensitivity 82.6%, specificity 96%, PPV 96.2% and NPV 85.7% (cut-off 0.5). ANN is superior to PELD-MELD for predicting poor outcome in PALF.

Health professionals', expert patients' and dieters' beliefs and attitudes about obesity.

BACKGROUND: Research has suggested that patients and treatment providers hold different beliefs and models of obesity. This could impact upon the consistency and quality of interventions for weight management. The present study investigated the attitudes and beliefs of health professionals, commercial weight management advisors (expert patients) and overweight and obese dieters, towards obesity. METHODS: Data were collected using a self-administered questionnaire from 287 health professionals, 85 expert patients and 116 dieters. Respondents gave their views on obesity causation and consequences, and the most efficacious means to manage obesity. Demographic data and self-reported height and weight were also collected. Factor analysis, analysis of variance and t-tests were used to analyse the data. RESULTS: Health professionals, expert patients and dieters held similar models of obesity, identifying the same causes (lifestyle causes), consequences (medical consequences) and treatments (current recommended options) of obesity/overweight. CONCLUSIONS: The findings of the present study indicate a broader similarity between beliefs and attitudes of those involved in obesity treatment and those that they aim to treat than was previously assumed. The concordance of beliefs between patients and treatment providers is an encouraging finding and may have important implications for public health strategies in this area.

A recessive contiguous gene deletion causing infantile hyperinsulinism, enteropathy and deafness identifies the Usher type 1C gene.

Usher syndrome type 1 describes the association of profound, congenital sensorineural deafness, vestibular hypofunction and childhood onset retinitis pigmentosa. It is an autosomal recessive condition and is subdivided on the basis of linkage analysis into types 1A through 1E. Usher type 1C maps to the region containing the genes ABCC8 and KCNJ11 (encoding components of ATP-sensitive K + (KATP) channels), which may be mutated in patients with hyperinsulinism. We identified three individuals from two consanguineous families with severe hyperinsulinism, profound congenital sensorineural deafness, enteropathy and renal tubular dysfunction. The molecular basis of the disorder is a homozygous 122-kb deletion of 11p14-15, which includes part of ABCC8 and overlaps with the locus for Usher syndrome type 1C and DFNB18. The centromeric boundary of this deletion includes part of a gene shown to be mutated in families with type 1C Usher syndrome, and is hence assigned the name USH1C. The pattern of expression of the USH1C protein is consistent with the clinical features exhibited by individuals with the contiguous gene deletion and with isolated Usher type 1C.

Methadone-related death in detention.

Oral methadone may be prescribed to detainees with the aim of minimising the risk of fatal opioid poisoning on release. To study the circumstances under which methadone-related deaths can occur in detention, we audited reports of 17 [14 male, 3 female; median (range) age 34 (22-52) years] such deaths, July 2010-December 2011. The median (range) methadone dose was 40 (10-110) mg/d (N = 16). The median (range) post-mortem blood methadone concentration was 0.42 (0.16-1.40) mg/L. Those who died within 7 days of the commencement of methadone treatment were significantly younger (Mann-Whitney U 102.5, p < 0.05), were prescribed a significantly lower dose (U = 80.0, p < 0.05) and had significantly lower blood methadone concentrations at death (U = 106.5, p < 0.02) than in those given methadone long-term. In 8 reports the prisoner had been recorded as either 'sleepy' (N = 7), or 'unwell' in the hours before death. In 13 deaths, the prisoner was either found dead first thing in the morning, or in one instance could not be roused ('snoring heavily'). Pneumonia, tracheobronchitis, end-stage cirrhosis, and ischaemic heart disease/coronary artery atherosclerosis were cited as associated factors in four patients, all of whom were on long term stable methadone treatment. Attention to warning signs of likely methadone toxicity (daytime or excessive drowsiness, snoring, nausea/vomiting) and associated risk factors (use of drugs such as benzodiazepines and gabapentinoids, the presence of respiratory infection, liver or renal disease) could help minimise the risk of unexpected death in patients given methadone.

Streaked sub-ps-resolution x-ray line shapes and implications for solid-density plasma dynamics (invited).

A high-resolution x-ray spectrometer was coupled with an ultrafast x-ray streak camera to produce time-resolved line shape spectra measured from hot, solid-density plasmas. A Bragg crystal was placed near laser-produced plasma to maximize throughput; alignment tolerances were established by ray tracing. The streak camera produced single-shot, time-resolved spectra, heavily sloped due to photon time-of-flight differences, with sufficient reproducibility to accumulate photon statistics. The images are time-calibrated by the slope of streaked spectra and dewarped to generate spectra emitted at different times defined at the source. The streaked spectra demonstrate the evolution of spectral shoulders and other features on ps timescales, showing the feasibility of plasma parameter measurements on the rapid timescales necessary to study high-energy-density plasmas.

Treatment outcomes of bladder stones in children with intact bladders in developing countries: A systematic review of >1000 cases on behalf of the European Association of Urology Bladder Stones Guideline panel.

INTRODUCTION: Bladder stones (BS) are still endemic in children in developing nations and account for a high volume of paediatric urology workload in these areas. The aim of this systematic review is to comparatively assess the benefits and risks of minimally invasive and open surgical interventions for the treatment of bladder stones in children. METHODS: This systematic review was conducted in accordance with Cochrane Guidance. Database searches (January 1970- March 2021) were screened, abstracted, and assessed for risk of bias for comparative randomised controlled trials (RCTs) and non-randomised studies (NRSs) with >10 patients per group. Open cystolithotomy (CL), transurethral cystolithotripsy (TUCL), percutaneous cystolithotripsy (PCCL), extracorporeal shock wave lithotripsy (ESWL) and laparoscopic cystolithotomy (LapCL) were evaluated. RESULTS: In total, 3040 abstracts were screened, and 8 studies were included. There were 7 retrospective non-randomised studies (NRS's) and 1 quasi-RCT with 1034 eligible patients (CL: n=637, TUCL: n=196, PCCL: n=138, ESWL: n=63, LapCL n=0). Stone free rate (SFR) was given in 7 studies and measured 100%, 86.6%-100%, and 100% for CL, TUCL and PCCL respectively. CL was associated with a longer duration of inpatient stay than PCCL and TUCL (p<0.05). One NRS showed that SFR was significantly lower after 1 session with outpatient ESWL (47.6%) compared to TUCL (93.5%) and CL (100%) (p<0.01 and p<0.01 respectively). One RCT compared TUCL with laser versus TUCL with pneumatic lithotripsy and found that procedure duration was shorter with laser for stones <1.5cm (n=25, p=0.04). CONCLUSION: In conclusion, CL, TUCL and PCCL have comparable SFRs but ESWL is less effective for treating stones in paediatric patients. CL has the longest duration of inpatient stay. Information gathered from this systematic review will enable paediatric urologists to comparatively assess the risks and benefits of all urological modalities when considering surgical intervention for bladder stones.

Quantifying electron temperature distributions from time-integrated x-ray emission spectra.

K-shell x-ray emission spectroscopy is a standard tool used to diagnose the plasma conditions created in high-energy-density physics experiments. In the simplest approach, the emissivity-weighted average temperature of the plasma can be extracted by fitting an emission spectrum to a single temperature condition. It is known, however, that a range of plasma conditions can contribute to the measured spectra due to a combination of the evolution of the sample and spatial gradients. In this work, we define a parameterized model of the temperature distribution and use Markov Chain Monte Carlo sampling of the input parameters, yielding uncertainties in the fit parameters to assess the uniqueness of the inferred temperature distribution. We present the analysis of time-integrated S and Fe x-ray spectroscopic data from the Orion laser facility and demonstrate that while fitting each spectral region to a single temperature yields two different temperatures, both spectra can be fit simultaneously with a single temperature distribution. We find that fitting both spectral regions together requires a maximum temperature of 1310-70 +90 eV with significant contributions from temperatures down to 200 eV.

Infections, hospitalisations, and deaths averted via a nationwide vaccination campaign using the Pfizer-BioNTech BNT162b2 mRNA COVID-19 vaccine in Israel: a retrospective surveillance study.

BACKGROUND: On Dec 20, 2020, Israel initiated a nationwide COVID-19 vaccination campaign for people aged 16 years and older and exclusively used the Pfizer-BioNTech BNT162b2 mRNA COVID-19 vaccine (tozinameran). We provide estimates of the number of SARS-CoV-2 infections and COVID-19-related admissions to hospital (ie, hospitalisations) and deaths averted by the nationwide vaccination campaign. METHODS: In this retrospective surveillance study, we used national surveillance data routinely collected by the Israeli Ministry of Health from the first 112 days (Dec 20, 2020, up to our data cutoff of April 10, 2021) of Israel's vaccination campaign to estimate the averted burden of four outcomes: SARS-CoV-2 infections and COVID-19-related hospitalisations, severe or critical hospitalisations, and deaths. As part of the campaign, all individuals aged 16 years and older were eligible for inoculation with the BNT162b2 vaccine in a two-dose schedule 21 days apart. We estimated the direct effects of the immunisation programme for all susceptible individuals (ie, with no previous evidence of laboratory-confirmed SARS-CoV-2 infection) who were at least partly vaccinated (at least one dose and at least 14 days of follow-up after the first dose). We estimated the number of SARS-CoV-2 infection-related outcomes averted on the basis of cumulative daily, age-specific rate differences, comparing rates among unvaccinated individuals with those of at least partly vaccinated individuals for each of the four outcomes and the (age-specific) size of the susceptible population and proportion that was at least partly vaccinated. FINDINGS: We estimated that Israel's vaccination campaign averted 158 665 (95% CI 144 640-172 690) SARS-CoV-2 infections, 24 597 (18 942-30 252) hospitalisations, 17 432 (12 770-22 094) severe or critical hospitalisations, and 5532 (3085-7982) deaths. 16 213 (65·9%) of 24 597 hospitalisations and 5035 (91·0%) of 5532 of deaths averted were estimated to be among those aged 65 years and older. We estimated 116 000 (73·1%) SARS-CoV-2 infections, 19 467 (79·1%) COVID-19-related hospitalisations, and 4351 (79%) deaths averted were accounted for by the fully vaccinated population. INTERPRETATION: Without the national vaccination campaign, Israel probably would have had triple the number of hospitalisations and deaths compared with what actually occurred during its largest wave of the pandemic to date, and the health-care system might have become overwhelmed. Indirect effects and long-term benefits of the programme, which could be substantial, were not included in these estimates and warrant future research. FUNDING: Israel Ministry of Health and Pfizer.

The challenges for nut-allergic consumers of eating out.

BACKGROUND: For individuals with a nut allergy, the avoidance of allergens is particularly challenging in situations where they are not preparing their own food. Many allergic reactions occur when eating outside the home. OBJECTIVE: To identify and explore the challenges faced by nut-allergic individuals (NAIs) when they are eating in restaurants and other eating establishments. METHODS: A qualitative interview study was conducted with 32 adults with a clinical history of allergy to peanuts and/or tree nuts. RESULTS: The main strategies that participants adopted to manage the risk of allergic reactions when eating outside the home were avoidance and communication. They avoided types of restaurants, meal courses or particular foods. Seeking familiarity was a key strategy that enabled NAIs to reduce uncertainty and anxiety. Language differences were a major barrier to confident communication about food content. The need to check whether the food on offer may contain nuts was a source of social embarrassment for many participants and the desire to avoid this sometimes led to increased risk taking. Some did not disclose their allergy to restaurant staff as they feared a conservative reaction that would further constrain food choices. NAIs often have to plan where to eat out. The consequent lack of spontaneity was a source of regret to some. CONCLUSION AND CLINICAL RELEVANCE: Communication patterns of nut-allergic adults are often grounded in legitimate everyday social considerations around embarrassment, choice and spontaneity. Education and training strategies are needed that recognize and take account of this. Focusing on communication deficits of NAIs may be unhelpful; responsibility for food safety must be shared with the food industry.

Measurements of electron transport in foils irradiated with a picosecond time scale laser pulse.

The heating of solid foils by a picosecond time scale laser pulse has been studied by using x-ray emission spectroscopy. The target material was plastic foil with a buried layer of a spectroscopic tracer material. The laser pulse length was either 0.5 or 2 ps, which resulted in a laser irradiance that varied over the range 10(16)-10(19) W/cm(2). Time-resolved measurements of the buried layer emission spectra using an ultrafast x-ray streak camera were used to infer the density and temperature conditions as a function of laser parameters and depth of the buried layer. Comparison of the data to different models of electron transport showed that they are consistent with a model of electron transport that predicts the bulk of the target heating is due to return currents.

How do peanut and nut-allergic consumers use information on the packaging to avoid allergens?

BACKGROUND: Recent legislation has sought to improve the information printed on packaged foods relevant to the safety of food allergic consumers. We aimed to understand the complex risk assessment decisions made by peanut and nut-allergic adults when purchasing food, with particular reference to use of printed package information. METHODS: The behaviour and 'thinking aloud' of 32 participants were recorded during their normal food shop, followed by a semi-structured interview. During the interview they were given 13 potentially problematic packaged foods, and asked if they would purchase the product and what their reasons were. Transcribed data from the shop, interview and 13-product task were analysed to explore use of allergy advice boxes, ingredients lists and other packaging information. RESULTS: Some participants used the ingredients list as their primary check for allergens, but most used the allergy advice box. Package-based information was generally considered reliable, but some supermarket and brand labels were trusted more than others. Images and product names were used to draw inferences about the presence of nuts. A number of improvements were suggested by participants, particularly a request for more 'nut free' labelling. CONCLUSIONS: Food labels were used in conjunction with nonpacket-based strategies (e.g. previous experience) to make choices. External factors (e.g. trust of manufacturer) informed interpretation of and confidence in labels. Images and product names, not intended by manufacturers as an allergen risk assessment aid, were also used to inform choices.

Loss of functional KATP channels in pancreatic beta-cells causes persistent hyperinsulinemic hypoglycemia of infancy.

Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) is a disorder of childhood associated with inappropriate hypersecretion of insulin by the pancreas. The pathogenesis of the condition has hitherto remained controversial. We show here that insulin-secreting cells from a homogeneous group of five infants with PHHI lack ATP-sensitive K+ channel (KATP) activity. As a consequence, PHHI beta-cells are spontaneously electrically active with high basal cytosolic Ca2+ concentrations due to Ca2+ influx. Our findings define the pathogenesis of this disease as a novel K+ channel disorder.

Absolute throughput calibration of multiple spherical crystals for the Orion High-REsolution X-ray spectrometer (OHREX).

We present absolute throughput analysis of several crystals for the Orion High-REsolution X-ray (OHREX) imaging crystal spectrometer using ray tracing and experimental measurements. The OHREX spectrometer is a high-resolution x-ray spectrometer designed to measure spectral line shapes at the Orion laser facility. The spectrometer is fielded with up to two spherical crystals simultaneously covering two independent spectral ranges. Each crystal has a nominal radius of curvature of R = 67.2 cm and is fielded at a nominal Bragg angle of 51.3°. To cover different bands of interest, several different crystals are available, including Ge (111), KAP, and several cuts of quartz, whose resolving power λ/Δλ exceeds 10 000. The calibrated response of the available crystals has previously been reported from measurements at the EBIT-I electron beam ion trap at Lawrence Livermore National Laboratory. Here, we model the absolute throughput of each crystal using ray tracing and verify the results using experimental data for the quartz (101¯1) crystal.

Recent enhancements in the performance of the Orion high-resolution x-ray spectrometers.

During the past few years, the Orion high-resolution x-ray spectrometers have been successful tools for measuring x-ray spectra from plasmas generated in the Orion laser facility. Duplicate spectrometers also operate successfully at the Livermore EBIT-I and SuperEBIT electron beam ion traps for measuring x-ray polarization. We have recently implemented very high-quality, optically bonded, spherically bent quartz crystals to remove the structure in the x-ray image that had been observed in earlier measurements. The structure had been caused by focusing defects and limited the accuracy of our measurements. We present before and after images that show a drastic improvement. We, furthermore, have implemented a spherically bent potassium acid phthalate (KAP) crystal on one of our spectrometers. The KAP crystal was prepared in a similar fashion, and we present measurements of the N Ly-ß and Ne Lyß lines taken in first- and second-order reflections at 600 and 1200 eV, respectively. These measurements confirm that KAP crystals can be produced at a quality suitable for extending the spectral coverage to wavelengths longer than those accessible by different quartz crystals, especially those that cover the astrophysically important lines of iron.