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DOE OSTI2021

Ground-based temperature and humidity profiling: combining active and passive remote sensors

Abstract. Thermodynamic profiles in the planetary boundary layer (PBL) are important observations for a range of atmospheric research and operational needs. These profiles can be retrieved from passively sensed spectral infrared (IR) or microwave (MW) radiance observations or can be more directly measured by active remote sensors such as water vapor differential absorption lidars (DIALs). This paper explores the synergy of combining ground-based IR, MW, and DIAL observations using an optimal-estimation retrieval framework, quantifying the reduction in the uncertainty in the retrieved profiles and the increase in information content as additional observations are added to IR-only and MW-only retrievals. This study uses ground-based observations collected during the Perdigão field campaign in central Portugal in 2017 and during the DIAL demonstration campaign at the Atmospheric Radiation Measurement Southern Great Plains site in 2017. The results show that the information content in both temperature and water vapor is higher for the IR instrument relative to the MW instrument (thereby resulting in smaller uncertainties) and that the combined IR + MW retrieval is very similar to the IR-only retrieval below 1.5 km. However, including the partial profile of water vapor observed by the DIAL increases the information content in the combined IR + DIAL and MW + DIAL water vapor retrievals substantially, with the exact impact vertically depending on the characteristics of the DIAL instrument itself. Furthermore, there is a slight increase in the information content in the retrieved temperature profile using the IR + DIAL relative to the IR-only; this was not observed in the MW + DIAL retrieval.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS1988

Powerful warm infrared sources in early-type galaxies

IRAS far-infrared sources have been identified with 129 S0, Sa, Sb, and Sc galaxies in a statistically complete sample of 738 galaxies brighter than 14.5 mag and smaller than 4.0 arcmin. In most cases, the far-IR colors and the ratios of far-IR flux to radio flux density are those of normal galactic disks and/or starbursts. The most powerful far-IR sources in S0 and Sa galaxies are just as powerful as the strongest far-IR sources in Sb and Sc galaxies. Bright-IR sources in S0 and Sa galaxies are warm; those in Sc galaxies are cool. Sb galaxies have both warm and cool IR sources. Bright warm IR sources occur much more frequently in barred galaxies than in galaxies without bars for types S0, Sa, and Sb. Bright, cool IR sources are found with increasing frequency along the Hubble sequence, regardless of the presence or absence of a bar. At least some 'S0' galaxies with warm, bright IR sources have peculiar morphologies and ambiguous classifications.

Dressel, L. L.↗

NASA NTRS1988

Infrared opportunities for supernova 1987A

IR observations of SN 1987A are reviewed, focusing on the IR processes in the supernova. IR line emission, IR emission from supernova condensates, IR echoes, IR emission from shock-heated dust, and IR emission from a cometary cloud are examined. A list is given of IR studies of SN 1987A and the characteristics of the instruments used in these studies. Preliminary results from several IR studies are considered.

Dwek, Eli↗

NASA NTRS1991

Infrared technology XVII; Proceedings of the Meeting, San Diego, CA, July 22-26, 1991

Recent advances in IR technologies and their application to all types of IR systems are reported focusing on the JPL Space Infrared Telescope Facility (SIRTF), JPL instruments and systems for observation of earth and the atmosphere, staring arrays and thermal imaging, ten-year updates of IR techniques, infrared in the USSR, simulation and testing, focal-plane and optical technologies, and military and scientific applications. Particular attention is given to SIRTF stray light analysis, SIRTF focal-plane technologies, long-wave IR detectors based on III-V materials, IR lidars for atmospheric remote sensing, a firefly system concept, a high-fill-factor monolithic IR image sensor, atmospheric laser-transmission tables simply generated, ORION semiconductor optical detectors, postprocessing of thermograms in IR nondestructive testing, evaluation of the IR signature of dynamic air targets, the current status of InGaAs detector arrays for 1-3 microns, a dual-band optical system for IR multicolor signal processing, and blackbody radiators for field calibration.

Andresen, Bjorn F.↗

NASA NTRS2000

Upper Eocene Spherules at ODP Site 1090B

Our two labs independently discovered upper Eocene microtektites and microkrystites at ODP Site 1090, a new South Atlantic locality near the Agulhus Ridge. This is a significant new data point for the strewn fields of these spherules, which were recently extended into the Atlantic sector of the Southern Ocean when they were reported at ODP Site 689 on the Maude Rise. The microtektites have been regarded as related to North American tektites and the microkrystites as belonging to the clinopyroxene-bearing (cpx) spherule strewn field. Initial reports indicate that Site 1090 contains a complete sequence of upper Eocene sediments composed of diatom and nannofossil oozes. The magneto- and bio-stratigraphy indicate that impact-age sediments should occur in core 30X of Hole 1090B. One of us (FTK) took 2 cc samples at 10 cm intervals over 600 cm of core for Ir analyses and the senior author (SL) took 3 cc samples at 20 cm intervals to search for spherules. Both studies proved successful and additional samples were obtained to confirm initial results and better define the Ir anomaly and spherule abundances. Peak Ir concentrations of 0.97 ng/g were found at 1090B-30X-5, 105-106cm and 0.78 ng/g at 115-116 cm. Anomalous Ir concentrations (greater than 0.1 ng/g) extend over about 100 cm of core. Preliminary results indicate that the excess Ir at this site is about 25 ng per sq cm. About 380 microtektites (>63 pm) and 2492 microkrystites (>63 pm) were recovered over a 1.8 m interval with a peak abundance of microtektites (106/gram) and microkrystites (562/gram) at 1090B-30X- 5, 114-115 cm. The largest microtektite is approximately 960 x 1140 micron in size. About 55 % are spherical, and the rest are disc, cylinder, dumbbell, teardrop, or fragments. Most of the microtektites are transparent colorless, but a few are transparent pale brown or green. Preliminary data indicate that the microtektites at Site 1090 have similar major oxide compositions to those at Site 689. About 50% of the cpx spherules are spherical, the rest are fragments. They range from yellowish translucent to dark opaque. Based on stratigraphic data, occurrence of a positive Ir anomaly, and similar appearance and major oxide compositions of the Site 1090 spherules to those at Site 689, we believe that the spherule layer(s) are the same at both sites. However, there are significant differences between these two sites. At Site 689 the peak abundance of the cpx spherules is slightly below that of the microtektites. We can distinguish no such separation at Site 1090, despite a somewhat higher sediment accumulation rates. Peak Ir concentrations are about four times higher at Site 1090, resulting in a similarly higher total flux of Ir for this site compared to Site 689 on the Maude Rise. This is generally consistent with the flux of cpx spherules (greater than 63 pm) which is estimated to be approximately -2100 per sq cm, about twice that of Site 689D (1040 sq cm) and with the cpx-spherule component being a principal carrier of the Ir signal. The number of microtektites per sq cm (greater than 63 micron) is nearly the same at both sites, approximately 300 in 1090B and 280 in 689B. A decrease in the greater than 63 micron size fraction (consisting primarily of diatoms and radiolaria) is coincident with the spherule layer at both sites suggesting that the impact(s) that produced the spherule layer(s) may have had an adverse affect on the marine plankton.

Liu, S.↗

NASA NTRS2002

Iridium and Spherules in Late Eocene Impact Deposits

We have been independently examining the Ir (FTK) and spherule (SL) contents of recently discovered late Eocene impact deposits from the south Atlantic and western Indian oceans. These include ODP Sites 1090 [14,15], 709 [lo], and 699 [Liu in prep.]. Iridium abundances at these sites are within the typical range reported for late Eocene deposits, with peak concentrations between 100 and 1000 pg/g. In Table 1 we present estimated net Ir fluences (in ng Ir/cm ) for these and nine other sites. Although there are fewer sites than the K/T boundary, the average of 9 ng Ir/cm2 is probably a good estimate of the late Eocene global flux. This is enough Ir for a 6 km comet (assuming 250 ng/g Ir, p=1.5), is sufficient to produce the Popigai or Chesapeake Bay structures, and is 16% of the flux estimated for the K/T boundary (55 ng/cm2 [ 161). Figure 1 shows the relative abundances of Ir, glassy microtektites and cpx-bearing spherules in sediments from Sites 699 and 1090, which are separated by only 3100 km. Although these two sites have similar Ir anomalies, the abundances of spherules are quite different. Site 1090 has well-defined peaks for both types of spherules, with a peak of 562 cpx spheruledg, while Site 699 contains only a few glassy microtektites and no cpx spherules. While the different abundances of spherules may reflect a heterogeneous distribution of spherules on the Earth s surface, an equally likely cause of this difference may be differential preservation of spherules in the sediment. recovered are only a trace residue of the initial impact deposit. Earlier work found 0.22 ng/g Ir in glassy microtektites from Site 689 [17], an insufficient concentration to support 0.16 ng/g in the bulk sediment at this site. We measured 15 ng/g Ir in a group of 95 cpx spherules from Site 1090 with sizes from 63 to -200 pm, a set typical of the size distribution at this site. Although this is a significant concentration it also cannot support the Ir peak. We presently lack quantitative data on the mass concentration of cpx spherules in Site 1090 sediments, but it is certainly <1 mg/g in The impact record in the late Eocene is very different from that at the Cretaceous-Tertiary In contrast, the late Eocene probably experienced multiple impact events.

Kyte, F. T.↗

NASA NTRS2018

Evaluation of Soil Moisture Estimated from IASI Measurements

A simple yet effective scheme to estimate volumetric soil moisture (VSM) using infrared (IR) land surface emissivity retrieved from satellite IR spectral radiance measurements was recently developed, assuming other parameters impacting the radiative transfer (e.g., temperature, vegetation coverage, and surface roughness) are known for an acceptable time and space reference location. This scheme was applied to a decade of global IR emissivity data retrieved from MetOp-A Infrared Atmospheric Sounding Interferometer measurements. Global datasets of monthly-mean 0.25° spatial-grid VSM, estimated from IR emissivity data (denoted as IR-VSM), are assembled to compare with those routinely provided by satellite microwave (MW) multi-sensor measurements (obtained from the ESA CCI website). The IR-VSM dataset is used to demonstrate its spatial variations as well as seasonal-cycles and inter-annual variability which are spatially coherent and consistent with that from MW measurements. Herein we report on some initial evaluation of the IR-VSM absolute values using in-situ measurements available from the Soil Climate Analysis Network of the USDA website. From the 114 ground station locations, we infer a mean bias between monthly-mean in-situ VSM and satellite derived IR-VSM of 0.005 (m3/m3) over the past decade, despite the differences between physical measurements. The absolute accuracy of IR-VSM is also evaluated using an independent source of soil moisture measurements.

Zhou, Daniel K.↗

DOE OSTI2026

Design of a Cryogenic Assembly for Comparing Qubit Infrared Packaging Inefficiencies

It is well known that everything emits infrared (IR) light in the form of thermal radiation. IR radiation on superconducting qubits carries enough energy to cause decoherence and so-called “quasiparticle poisoning.” Therefore, proper IR shielding is needed to keep the qubit in a high-coherence state. However, trying to extract IR-specific information from a qubit is difficult, so a microwave kinetic inductance detector (MKID) can be used instead. We show that the IR shielding inefficiencies of MKID packages can only be compared with other packaging inefficiencies. We create a cryogenic assembly CAD design, consisting of magnetic shield cans, a copper mounting plate and mounts, and an MKID enclosure, which thermalizes the assembly to dilution refrigerator temperatures. Phase 1 of this design involves using a narrowband IR laser source to test the IR shielding of packaging at the laser’s wavelength. When the best IR shielding packaging is determined, the superconducting qubit can replace the MKID, allowing the qubit to avoid decoherence due to IR radiation and boost its performance and coherence lifetime.

Mailliard, Robert J. [Fermilab] (ORCID:00090000277↗

DOE OSTI2026

CMS Outer Tracker Module QA

Hobbeheydar, Samuel [Carnegie Mellon U. (main); Fe↗

DOE OSTI2026

Highly Responsive Near-Infrared Photodetector Based on Contactless PdSe 2 Integration with a Few-Layered MoSe 2 Field-Effect Transistor

Two-dimensional (2D) semiconductors with narrow bandgaps are promising candidates for near- and far-infrared (IR) photodetection, particularly in the telecommunication spectral window. However, current low-bandgap IR photodetectors face significant challenges due to their high dark current, increased carrier recombination, and thermally generated noise. Here, in this work, a hybrid phototransistor is demonstrated by integrating direct, contact-free palladium diselenide (PdSe 2 ) as a highly responsive IR detection layer with a non-IR-absorbing molybdenum diselenide (MoSe 2 ) field-effect transistor (FET), using a near-IR source at a wavelength of λ = 1650 nm. Exfoliated PdSe 2 flakes integrated into a back-gated FET architecture exhibit ambipolar transport behavior, with extracted hole and electron mobilities of 24.8 cm 2 V –1 s –1 and 58.4 cm 2 V –1 s –1 , respectively. The devices show a clear photocurrent generation under the illumination of a λ = 1650 nm laser source, achieving a notable responsivity of ∼300 mA W -1 at an applied gate voltage of 15 V, which highlights the suitability of PdSe 2 as a narrow-bandgap material for photodetection. Photoresponsivity saturates and does not have any effect above an applied gate voltage of 15 V. To further tune the photoresponsivity performance continuously with the applied gate voltage, we construct a van der Waals heterostructure phototransistor, where few layers of PdSe 2 are directly transferred onto the 2D channel region of a MoSe 2 FET, while avoiding any contact with the metal electrodes. In this heterostructure, PdSe 2 works as the primary active IR-absorbing layer, while MoSe 2 provides high-performance FET characteristics. This spatial separation of absorption and transport facilitates efficient interlayer charge transfer and charge separation, resulting in high responsivities of up to 972 mA W –1 at near-IR wavelengths and a low power density of 1.5 mW/mm 2 . The responsivity of our photodetector is comparable to that of some state-of-the-art commercially available NIR photodetectors, highlighting the potential of PdSe 2 -based heterostructures as scalable, CMOS-compatible platforms for high-performance near-IR detection.

Infrared (IR) photodetectors↗

DOE OSTI2020

Materials Data on Yb2Ge2Ir by Materials Project

Yb2IrGe2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Yb sites. In the first Yb site, Yb is bonded in a 6-coordinate geometry to two equivalent Ir and six Ge atoms. Both Yb–Ir bond lengths are 3.29 Å. There are a spread of Yb–Ge bond distances ranging from 2.95–3.29 Å. In the second Yb site, Yb is bonded in a 2-coordinate geometry to four equivalent Ir and seven Ge atoms. There are a spread of Yb–Ir bond distances ranging from 3.14–3.22 Å. There are a spread of Yb–Ge bond distances ranging from 2.99–3.47 Å. Ir is bonded in a 10-coordinate geometry to six Yb and four Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.48–2.59 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to seven Yb, one Ir, and one Ge atom. The Ge–Ge bond length is 2.61 Å. In the second Ge site, Ge is bonded in a 10-coordinate geometry to six Yb, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.83 Å.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on SiIr3 by Materials Project

Ir3Si crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a distorted square co-planar geometry to four equivalent Si atoms. All Ir–Si bond lengths are 2.64 Å. In the second Ir site, Ir is bonded in a distorted water-like geometry to two equivalent Si atoms. Both Ir–Si bond lengths are 2.44 Å. Si is bonded in a 8-coordinate geometry to eight Ir atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on NbGeIr by Materials Project

NbIrGe crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Nb is bonded in a 11-coordinate geometry to six equivalent Ir and five equivalent Ge atoms. There are a spread of Nb–Ir bond distances ranging from 2.96–3.07 Å. There are a spread of Nb–Ge bond distances ranging from 2.72–2.83 Å. Ir is bonded in a 12-coordinate geometry to six equivalent Nb, two equivalent Ir, and four equivalent Ge atoms. Both Ir–Ir bond lengths are 2.87 Å. There are a spread of Ir–Ge bond distances ranging from 2.47–2.55 Å. Ge is bonded in a 9-coordinate geometry to five equivalent Nb and four equivalent Ir atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Sr3(SnIr)4 by Materials Project

Sr3(IrSn)4 crystallizes in the cubic I-43m space group. The structure is three-dimensional. Sr is bonded in a 12-coordinate geometry to four equivalent Ir and four equivalent Sn atoms. All Sr–Ir bond lengths are 3.39 Å. All Sr–Sn bond lengths are 3.36 Å. Ir is bonded in a 4-coordinate geometry to three equivalent Sr, three equivalent Ir, and four equivalent Sn atoms. All Ir–Ir bond lengths are 2.88 Å. There are one shorter (2.58 Å) and three longer (2.72 Å) Ir–Sn bond lengths. Sn is bonded in a 7-coordinate geometry to three equivalent Sr and four equivalent Ir atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Nd2Ge2Ir by Materials Project

Nd2IrGe2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Nd sites. In the first Nd site, Nd is bonded in a 9-coordinate geometry to three equivalent Ir and six Ge atoms. There are two shorter (3.16 Å) and one longer (3.32 Å) Nd–Ir bond lengths. There are a spread of Nd–Ge bond distances ranging from 2.91–3.51 Å. In the second Nd site, Nd is bonded in a 3-coordinate geometry to one Ir and five equivalent Ge atoms. The Nd–Ir bond length is 2.96 Å. There are a spread of Nd–Ge bond distances ranging from 3.11–3.60 Å. Ir is bonded in a 8-coordinate geometry to four Nd and four Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.51–2.55 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to eight Nd and two equivalent Ir atoms. In the second Ge site, Ge is bonded in a 6-coordinate geometry to three equivalent Nd, two equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.59 Å.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Ho3Ge3Ir2 by Materials Project

Ho3Ir2Ge3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 11-coordinate geometry to four equivalent Ir and seven Ge atoms. There are a spread of Ho–Ir bond distances ranging from 2.98–3.28 Å. There are a spread of Ho–Ge bond distances ranging from 3.02–3.24 Å. In the second Ho site, Ho is bonded in a 9-coordinate geometry to four equivalent Ir and five Ge atoms. All Ho–Ir bond lengths are 3.07 Å. There are a spread of Ho–Ge bond distances ranging from 3.02–3.11 Å. Ir is bonded in a 10-coordinate geometry to six Ho and four Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.50–2.70 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to seven Ho and two equivalent Ir atoms. In the second Ge site, Ge is bonded in a 10-coordinate geometry to six Ho, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.76 Å.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Lu3Ge3Ir2 by Materials Project

Lu3Ir2Ge3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Lu sites. In the first Lu site, Lu is bonded in a 11-coordinate geometry to four equivalent Ir and seven Ge atoms. There are a spread of Lu–Ir bond distances ranging from 2.93–3.24 Å. There are a spread of Lu–Ge bond distances ranging from 2.99–3.20 Å. In the second Lu site, Lu is bonded in a 9-coordinate geometry to four equivalent Ir and five Ge atoms. All Lu–Ir bond lengths are 3.04 Å. There are a spread of Lu–Ge bond distances ranging from 3.00–3.04 Å. Ir is bonded in a 10-coordinate geometry to six Lu and four Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.48–2.68 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 10-coordinate geometry to six Lu, three equivalent Ir, and one Ge atom. The Ge–Ge bond length is 2.69 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to seven Lu and two equivalent Ir atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Ca2SiIr2 by Materials Project

Ca2Ir2Si crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Ca is bonded in a 7-coordinate geometry to six equivalent Ir and one Si atom. There are a spread of Ca–Ir bond distances ranging from 3.01–3.15 Å. The Ca–Si bond length is 3.10 Å. Ir is bonded in a 9-coordinate geometry to six equivalent Ca, one Ir, and two equivalent Si atoms. The Ir–Ir bond length is 2.65 Å. There are one shorter (2.41 Å) and one longer (2.43 Å) Ir–Si bond lengths. Si is bonded in a 4-coordinate geometry to two equivalent Ca and four equivalent Ir atoms.

36 MATERIALS SCIENCE↗