The Infrared Imaging Spectrograph (IRIS): project status report

We present spectroscopic observations of the classical nova CP Crucis (Nova Crux 1996) obtained with the Infrared Space Observatory Short Wavelength Spectrometer (ISO SWS) and the Anglo-Australian Telescope using both the Infrared Imaging Spectrograph and the Royal Greenwich Observatory Spectrograph. From the expansion parallax, we find that CP Crucis lies at a distance of 2.6 ± 0.5 kpc and reached a maximum MV of -8.7 at 0.96 days after discovery. We find abundance enhancements versus solar by mass of 75, 17, and 27 for N, O, and Ne, respectively. Additionally, we constrain the Mg abundance in the ejecta to be approximately solar. Abundance analysis suggests CP Crucis is an old Population I binary system. Combining the strong N and Ne abundances with the relatively low Mg abundance and a Ne/O ratio of 0.5, we propose that CP Crucis is an example of the "missing link" between CO and ONeMg novae.

This status report covers progress on the two following areas: (1) Field Measurement, Analyses, and Reporting Related to Building Energy Systems and Biomass Projects. The key effort is on the Class B performance monitoring program, including a limited amount of special data evaluation and analysis. Other work relates to design tools, passive selection criteria, hot water performance documentation, and other renewable systems. (2) Technical Services in Support of Appropriate Technology Program. A total of 84 project files have been reviewed and summarized, telephone contacts and selected site visits are being made on a small number of active projects, and technical information dissemination tasks are underway. A summary paper on project activities was prepared and approved for publication.

This paper describes the construction and application of an integrated optomechanical raytrace model used for optical analysis support of the OTIS cryo-vacuum test of the James Webb Space Telescope (JWST) test campaign. OTIS is the Optical Telescope Element (OTE) and Integrated Science Instrument Module (ISIM). Four specific applications are described – 1) simulation of ambient over-lighting conditions from clean room luminaires and photogrammetry flashes, 2) PSF image motion predictions in the presence of auto-collimating flat (ACF) actuation, 3) science instrument field illumination (“shadowgrams”) checking for unexpected vignetting, and 4) pupil alignment simulations of the Near Infrared Imager and Slitless Spectrograph (NIRISS).

The MMT Adaptive optics exoPlanet characterization System (MAPS) is an exoplanet characterization program that encompasses instrument development, observational science, and education. The instrument we are developing for the 6.5m MMT observatory is multi-faceted, including a refurbished 336-actuator adaptive secondary mirror (ASM); two pyramid wavefront sensors (PyWFS's); a 1-kHz adaptive optics (AO) control loop; a high-resolution and long-wavelength upgrade to the Arizona infraRed Imager and Echelle Spectrograph (ARIES); and a new-AO-optimized upgrade to the MMT-sensitive polarimeter (MMT-Pol). With the completed MAPS instrument, we will execute a 60-night science program to characterize the atmospheric composition and dynamics of ~50-100 planets around other stars. The project is approaching first light, anticipated for Summer/Fall of 2022. With the electrical and optical tests complete and passing the review milestone for the ASM’s development, it is currently being tuned. The PyWFS's are being built and integrated in their respective labs: the visible-light PyWFS at the University of Arizona (UA), and the infrared PyWFS at the University of Toronto (UT). The top-level AO control software is being developed at UA, with an on-sky calibration algorithm being developed at UT. ARIES development continues at UA, and MMT-Pol development is at the University of Minnesota. The science and education programs are in planning and preparation. We will present the design and development of the entire MAPS instrument and project, including an overview of lab results and next steps.

MAPS, MMT Adaptive optics exoPlanet characterization System, is the upgrade of legacy 6.5m MMT adaptive optics system. It is an NSF MSIP-funded project that includes (i) refurbishing of the MMT Adaptive Secondary Mirror (ASM), (ii) new high sensitive and high spatial order visible and near-infrared pyramid wavefront sensors, and (iii) the upgrade of Arizona Infrared Imager and Echelle Spectrograph (ARIES) and MMT high Precision Imaging Polarimeter (MMTPol) science cameras. This paper will present the design and development of the visible pyramid wavefront sensor. This system consists of an acquisition camera, a fast-steering tip-tilt modulation mirror, a double pyramid, a pupil imaging triplet lens, and a low noise and high-speed frame rate based CCID75 camera. We will report on hardware and software and present the laboratory characterization results of the individual subsystems, and outline the on-sky commissioning plan.

Atmospheric escape of close-in exoplanets, driven by stellar irradiation, influences their evolution, composition, and atmospheric dynamics. The near-infrared metastable helium triplet (10833 Å) has become a key probe of this process, enabling mass loss rate measurements for dozens of exoplanets. Only a few studies, however, have detected absorption beyond transit, supporting the presence of hydrodynamic outflows. None have yet precisely identified the physical extent of the out-of-transit signal, either due to non-continuous or short-duration observations. This strongly limits our ability to measure accurate mass-loss rates and to understand how the stellar environment shapes outflows. Here we present the continuous, full-orbit helium phase-curve observation of an exoplanet: the ultra-hot Jupiter WASP-121 b, obtained with the James Webb Space Telescope (JWST) and the Near Infrared Imager and Slitless Spectrograph (NIRISS). We detect significant helium absorption at >3σ over nearly 60% of the orbit, revealing a persistent and large-scale outflow. The signal separates into a dense leading tail moving toward the star and a trailing tail pushed away by stellar irradiation. Both appear to remain collisional far from the planet, implying strong hydrodynamic escape. While qualitatively consistent with theoretical expectations, current models cannot reproduce the full spatial and kinematic structure, limiting precise mass-loss estimates. These results demonstrate JWST's ability to map exoplanet outflows in detail and highlight its synergy with ground-based spectroscopy.

We present JWST/Near Infrared Spectrograph (NIRSpec) integral field spectroscopy (IFS) of a lensed Population III candidate stellar complex (dubbed Lensed And Pristine 1, LAP1), with a lensing-corrected stellar mass of ≲104 M⊙ and an absolute luminosity of MUV > −11.2 (mUV > 35.6), confirmed at redshift 6.639 ± 0.004. The system is strongly amplified (μ ≳ 100) by straddling a critical line of the Hubble Frontier Field galaxy cluster MACS J0416. Although the stellar continuum is currently not detected in the Hubble and JWST/Near Infrared Camera (NIRCam) and Near Infrared Imager and Slitless Spectrograph (NIRISS) imaging, arclet-like shapes of Lyman and Balmer lines, Lyα, Hγ, Hβ and Hα are detected with NIRSpec IFS with signal-to-noise ratios (S/N) of approximately 5 − 13 and large equivalent widths (> 300 − 2000 Å), along with a remarkably weak [O III]λλ4959, 5007 at S/N ≃ 4. LAP1 shows a large ionizing photon production efficiency, log(ξion[erg Hz−1]) > 26. From the metallicity indexes R23 = ([O III] + [O II])/Hβ ≲ 0.74 and R3 = ([O III]/Hβ) = 0.55 ± 0.14, we derive an oxygen abundance of 12 + log(O/H)≲6.3. Intriguingly, the Hα emission is also measured in mirrored subcomponents where no [O III] is detected, providing even more stringent upper limits on the metallicity if in situ star formation is ongoing in this region (12 + log(O/H) < 6). The formal stellar mass limit of the subcomponents would correspond to ∼103 M⊙ or MUV fainter than −10. Alternatively, this metal-free, pure line-emitting region could be the first case of a fluorescing H I gas region induced by transverse escaping ionizing radiation from a nearby star complex. The presence of large equivalent-width hydrogen lines and the deficiency of metal lines in such a small region make LAP1 the most metal-poor star-forming region currently known in the reionization era and a promising site that may host isolated, pristine stars.

The objective of the study reported here is to demonstrate that municipal sewage sludges can be anaerobically digested with little or no heating. To this end, two digesters at the Jackson Pike Wastewater Treatment Plant in Columbus, Ohio, have been converted to the anaerobic contact stabilization process. This, it is hoped, will permit positive and independent control of the solids retention time (SRT) in the system, so that solids may be retained long enough to ensure substantially complete digestion even at reduced temperatures. Digestion at a temperature of 71/sup 0/F and an SRT of 33 days produces results similar to digestion at a temperature of 91/sup 0/F and an SRT of 11 days. There is no evidence of impaired or unstable digestion at the lower temperature. (DMC)

Studies of the sulfation rate behavior show an initial fast rate followed by a rate decrease. It is generally agreed that product layer diffusion limitations are the explanation for this behavior. Many investigators tried to model this observed rate change, more or less successfully. No agreement has been reached, however, as to the value of the produce layer diffusivity. Hence, in this work we want to investigate the mechanism of this process. In addition to understanding the initial kinetics, two questions will be focused on. First, we should understand what is diffusing. It appears that the driving force for this diffusion phenomenon is not first order with the SO{sub 2} concentration in the gas. This would indicate that some other, intermediary step is occurring. The second question concerns the composition of the product layer. Different conditions at the start of the reaction were observed to produce different diffusion rates at a later stage. The microscopic appearance of the product layer also appeared to be different.

This report discusses documentation of sample quality and deterioration. Various tasks covered under this heading include: collection of samples, sampling handling and processing; characterization of coal samples; distribution of samples to users; operation of the DOE coal data base. (VC)

Progress in developing mathematical models to describe combustion conditions with and without swirl in automotive engine combustion chambers and calculations performed with these models are discussed. (LCL)

Headspace oxygen contents of several designated drums containing {minus}l inch and {minus}{1/4} inch coal were measured. These measurements were later discontinued by agreement with the Project Manager, as the leakage of plastic drums and buckets has been well documented. During the current reporting period a total of 65 data printouts were distributed. In addition, 10 special data requests were fulfilled by either search/sort and printout or creation of a data disk, resulting in distribution of limited information on 4,479 samples. Several preliminary requests for Sample Bank and Data Base information and price quotations have also been handled. Four hundred copies of the 61-page second edition of the booklet ``The Penn State Coal Sample Bank and Data Base`` were received from the printer. Changes in format have allowed increased content in fewer pages, to reduce printing and mailing costs. Three hundred thirty-nine copies were distributed. Data generated on samples DECS-1 through DECS-14 were added to the Penn State Coal Data Base. Map reference data were verified for all 14 samples.

Climatological data, both representative (typical) and extreme conditions, relevant to building energy use in Grandview, Missouri are presented. The energy-related characteristics of a particular building and its use are merged with ambient weather conditions. The graphs depict daily fluctuations in the major categories of building heating/cooling load for the experimental building (Roof Runner facility) at Butler Research Center. Data input include hourly weather and building occupancy schedules, the geometry and fixed thermal characteristics (component R-values, heat capacities, etc.) of the prototype structure, and variable conditions (status of moveable insulating shutters, HVAC operating modes, etc.). The prototype systems to be incorporated in the new Roof Runner building are shown. Both warehouse (no ceiling) and office (suspended ceiling) system types are included. The diagrams conceptually depict the heat flows in several representative operating modes, sampling the wide variety of operating conditions which will be evaluated during the testing phase of this project. Cost estimates for the designs selected for construction are provided. (MHR)

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