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1. Mapping and Characterization of Target-Site Resistance to Cyclic Ketoenol Insecticides in Cabbage Whiteflies, Aleyrodes proletella (Hemiptera: Aleyrodidae)

Author

Viola Müller, Frank Maiwald, Gudrun Lange, and Ralf Nauen

Subjects
insecticides, spiromesifen, spirotetramat, resistance, whiteflies, acetyl-CoA carboxylase, Science
Abstract

Cabbage whitefly, Aleyrodes proletella L., is an invasive hemipteran pest of cruciferous plants, particularly field brassica crops. Its importance has been increased over the last decade, particularly in European countries. The control of cabbage whiteflies largely relies on the application of synthetic insecticides, including tetronic and tetramic acid derivatives such as spiromesifen and spirotetramat (cyclic ketoenol insecticides), acting as insect growth regulators targeting acetyl-CoA carboxylase (ACC). In 2019, reduced efficacy against cabbage whiteflies of ketoenol insecticides at recommended label rates has been reported. Subsequently we collected field samples of A. proletella in different European countries and confirmed the presence of ketoenol resistance in laboratory bioassays. Reciprocal crossing experiments revealed an autosomal dominant trait, i.e., heterozygotes express a fully resistant phenotype. Transcriptome sequencing and assembly of ACC variants from resistant strains revealed the presence of an ACC target-site mutation, A2083V, as previously described and functionally validated in Bemisia tabaci (A2084V in A. proletella). Next, we employed a molecular genotyping assay to investigate the geographic spread of resistance and analyzed 49 populations collected in eight European countries. Resistance allele frequency was highest in the Netherlands, followed by Germany. Finally, we provide a proposal for the implementation of appropriate resistance management strategies.

Published
2024
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2. RF and Electronics Design of the Compact Ocean Wind Vector Radiometer

Author

Frank Maiwald, Oliver Montes, Sharmila Padmanabhan, Amy Wu, Zachary Pannell, Violet Torossian, Alireza Bakhshi, Damon Russell, Jordan Tanabe, Hamid Javadi, Chris Holman, Maurice Aghion, Richard Redick, Amarit Kitiyakara, and Shannon Brown

Subjects
Polarimetric microwave radiometer, noise sources, phase-matched RF components, Ocean engineering, TC1501-1800, Geophysics. Cosmic physics, QC801-809
Abstract

The Compact Ocean Wind Vector Radiometer (COWVR) was developed at the Jet Propulsion Laboratory as a proof of concept technology demonstration mission for the Air Force. COWVR is a fully polarimetric imaging radiometer system operating at 18.7, 23.8, and 33.9 GHz . Its receiver subsystem is based on the Jason-3 advanced microwave radiometer, which was launched in early 2016 and is currently in operation. Its enabling components are presented in this article, including the phase-matched waveguide components, noise injection, receivers, and polarimetric backend units.

Published
2020
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3. Completion of the AMR-C Instrument for Sentinel-6

Author

Frank Maiwald, Shannon T. Brown, Timothy Koch, Lance Milligan, Pekka Kangaslahti, Erich Schlecht, Anders Skalare, Matthew Bloom, Violet Torossian, John Kanis, Shannon Statham, Shawn Kang, and Parag Vaze

Subjects
Earth observation, internal and external noise source, microwave radiometer, radiometer performance, Ocean engineering, TC1501-1800, Geophysics. Cosmic physics, QC801-809
Abstract

The advanced microwave radiometer-climate quality (AMR-C) is a part of the European Sentinel-6A/B series, a collaboration between ESA and NASA, of two Earth-observing satellites, which will be launched in 2020 and 2025. Compared to its predecessor, Jason-3, the two AMR-C radiometer instruments have an external calibration system which enables higher radiometric stability accomplished by moving the secondary mirror between well-defined targets. Sentinel-6 allows continuing the study of the ocean circulation, climate change, and sea-level rise for at least another decade. Besides the external calibration for the AMR heritage radiometer (18.7, 23.8, and 34 GHz channels), the AMR-C contains a high-resolution microwave radiometer (HRMR) with radiometer channels at 90, 130, and 168 GHz. This subsystem allows for a factor of 5× higher spatial resolution at coastal transitions. This article presents a brief description of the instrument and the measured performance of the completed AMR-C-A and AMR-C-B instruments.

Published
2020
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4. Unique features of a global human ectoparasite identified through sequencing of the bed bug genome

Author

Joshua B. Benoit, Zach N. Adelman, Klaus Reinhardt, Amanda Dolan, Monica Poelchau, Emily C. Jennings, Elise M. Szuter, Richard W. Hagan, Hemant Gujar, Jayendra Nath Shukla, Fang Zhu, M. Mohan, David R. Nelson, Andrew J. Rosendale, Christian Derst, Valentina Resnik, Sebastian Wernig, Pamela Menegazzi, Christian Wegener, Nicolai Peschel, Jacob M. Hendershot, Wolfgang Blenau, Reinhard Predel, Paul R. Johnston, Panagiotis Ioannidis, Robert M. Waterhouse, Ralf Nauen, Corinna Schorn, Mark-Christoph Ott, Frank Maiwald, J. Spencer Johnston, Ameya D. Gondhalekar, Michael E. Scharf, Brittany F. Peterson, Kapil R. Raje, Benjamin A. Hottel, David Armisén, Antonin Jean Johan Crumière, Peter Nagui Refki, Maria Emilia Santos, Essia Sghaier, Sèverine Viala, Abderrahman Khila, Seung-Joon Ahn, Christopher Childers, Chien-Yueh Lee, Han Lin, Daniel S. T. Hughes, Elizabeth J. Duncan, Shwetha C. Murali, Jiaxin Qu, Shannon Dugan, Sandra L. Lee, Hsu Chao, Huyen Dinh, Yi Han, Harshavardhan Doddapaneni, Kim C. Worley, Donna M. Muzny, David Wheeler, Kristen A. Panfilio, Iris M. Vargas Jentzsch, Edward L. Vargo, Warren Booth, Markus Friedrich, Matthew T. Weirauch, Michelle A. E. Anderson, Jeffery W. Jones, Omprakash Mittapalli, Chaoyang Zhao, Jing-Jiang Zhou, Jay D. Evans, Geoffrey M. Attardo, Hugh M. Robertson, Evgeny M. Zdobnov, Jose M. C. Ribeiro, Richard A. Gibbs, John H. Werren, Subba R. Palli, Coby Schal, and Stephen Richards

Subjects
Science
Abstract

The bed bug, Cimex lectularius, is a ubiquitous human ectoparasite with global distribution. Here, the authors sequence the genome of the bed bug and identify reductions in chemosensory genes, expansion of genes associated with blood digestion and genes linked to pesticide resistance.

Published
2016
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7. A conserved hymenopteran-specific family of cytochrome P450s protects bee pollinators from toxic nectar alkaloids

Author

Julian Haas, Elena Beck, Bartlomiej J. Troczka, Angela Hayward, Gillian Hertlein, Marion Zaworra, Bettina Lueke, Benjamin Buer, Frank Maiwald, Michael E. Beck, Birgit Nebelsiek, Johannes Glaubitz, Chris Bass, and Ralf Nauen

Subjects
Multidisciplinary
Abstract

Many plants produce chemical defense compounds as protection against antagonistic herbivores. However, how beneficial insects such as pollinators deal with the presence of these potentially toxic chemicals in nectar and pollen is poorly understood. Here, we characterize a conserved mechanism of plant secondary metabolite detoxification in the Hymenoptera, an order that contains numerous highly beneficial insects. Using phylogenetic and functional approaches, we show that the CYP336 family of cytochrome P450 enzymes detoxifies alkaloids, a group of potent natural insecticides, in honeybees and other hymenopteran species that diverged over 281 million years. We linked this function to an aspartic acid residue within the main access channel of CYP336 enzymes that is highly conserved within this P450 family. Together, these results provide detailed insights into the evolution of P450s as a key component of detoxification systems in hymenopteran species and reveal the molecular basis of adaptations arising from interactions between plants and beneficial insects.

Published
2023
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9. Phylogenomic and functional characterization of an evolutionary conserved cytochrome P450-based insecticide detoxification mechanism in bees

Author

Julian Haas, Angela Hayward, Benjamin Buer, Frank Maiwald, Birgit Nebelsiek, Johannes Glaubitz, Chris Bass, and Ralf Nauen

Subjects
Evolution, Molecular, Insecticides, Neonicotinoids, Multidisciplinary, Cytochrome P-450 Enzyme System, Inactivation, Metabolic, Animals, Insect Proteins, Genes, Insect, Bees, Conserved Sequence, Phylogeny
Abstract

The regulatory process for assessing the risks of pesticides to bees relies heavily on the use of the honeybee,Apis mellifera, as a model for other bee species. However, the validity of usingA. melliferaas a surrogate for otherApisand non-Apisbees in pesticide risk assessment has been questioned. Related to this line of research, recent work onA. melliferahas shown that specific P450 enzymes belonging to the CYP9Q subfamily act as critically important determinants of insecticide sensitivity in this species by efficiently detoxifying certain insecticide chemotypes. However, the extent to which the presence of functional orthologs of these enzymes is conserved across the diversity of bees is unclear. Here we used a phylogenomic approach to identify > 100 putative CYP9Q functional orthologs across 75 bee species encompassing all major bee families. Functional analysis of 26 P450s from 20 representative bee species revealed that P450-mediated detoxification of certain systemic insecticides, including the neonicotinoid thiacloprid and the butenolide flupyradifurone, is conserved across all major bee pollinator families. However, our analyses also reveal thatCYP9Q-related genes are not universal to all bee species, with some Megachilidae species lacking such genes. Thus, our results reveal an evolutionary conserved capacity to metabolize certain insecticides across all major bee families while identifying a small number of bee species where this function may have been lost. Furthermore, they illustrate the potential of a toxicogenomic approach to inform pesticide risk assessment for nonmanaged bee species by predicting the capability of bee pollinator species to break down synthetic insecticides.

Published
2022
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10. Cytochrome P450 CYP81A10v7 in Lolium rigidum confers metabolic resistance to herbicides across at least five modes of action

Author

Stephen B. Powles, Susana González, Roland Beffa, Qin Yu, Jian Wang, Heping Han, and Frank Maiwald

Subjects
0106 biological sciences, 0301 basic medicine, Lolium rigidum, Population, ved/biology.organism_classification_rank.species, Plant Science, Biology, 01 natural sciences, Mesotrione, 03 medical and health sciences, chemistry.chemical_compound, Cytochrome P-450 Enzyme System, Botany, Halogenated Diphenyl Ethers, Lolium, Genetics, Atrazine, education, Plant Proteins, education.field_of_study, Cyclohexanones, Herbicides, ved/biology, food and beverages, Trifluralin, Oryza, Cell Biology, Plants, Genetically Modified, biology.organism_classification, Genetically modified rice, 030104 developmental biology, chemistry, Weed, Herbicide Resistance, 010606 plant biology & botany
Abstract

Rapid and widespread evolution of multiple herbicide resistance in global weed species endowed by increased capacity to metabolize (degrade) herbicides (metabolic resistance) is a great threat to herbicide sustainability and global food production. Metabolic resistance in the economically damaging crop weed species Lolium rigidum is well known but a molecular understanding has been lacking. We purified a metabolic resistant (R) subset from a field evolved R L. rigidum population. The R, the herbicide susceptible (S) and derived F2 populations were used for candidate herbicide resistance gene discovery by RNA sequencing. A P450 gene CYP81A10v7 was identified with higher expression in R vs. S plants. Transgenic rice overexpressing this Lolium CYP81A10v7 gene became highly resistant to acetyl-coenzyme A carboxylase- and acetolactate synthase-inhibiting herbicides (diclofop-methyl, tralkoxydim, chlorsulfuron) and moderately resistant to hydroxyphenylpyruvate dioxygenase-inhibiting herbicide (mesotrione), photosystem II-inhibiting herbicides (atrazine and chlorotoluron) and the tubulin-inhibiting herbicide trifluralin. This wide cross-resistance profile to many dissimilar herbicides in CYP81A10v7 transgenic rice generally reflects what is evident in the R L. rigidum. This report clearly showed that a single P450 gene in a cross-pollinated weed species L. rigidum confers resistance to herbicides of at least five modes of action across seven herbicide chemistries.

Published
2020
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12. The mustard leaf beetle, Phaedon cochleariae, as a screening model for exogenous RNAi-based control of coleopteran pests

Author

Frank Maiwald, Sven Geibel, Julia Ulrich, Ralf Nauen, Bettina Lueke, Gregor Bucher, Benjamin Buer, Sonja Mehlhorn, and Christian Ulrich Baden

Subjects
0106 biological sciences, Health, Toxicology and Mutagenesis, Phaedon cochleariae, 01 natural sciences, 03 medical and health sciences, RNA interference, Reference genes, Gene silencing, Animals, Red flour beetle, Gene, 030304 developmental biology, RNA, Double-Stranded, Genetics, 0303 health sciences, Tribolium, biology, fungi, food and beverages, General Medicine, biology.organism_classification, Coleoptera, 010602 entomology, RNA silencing, Larva, RNA Interference, PEST analysis, Agronomy and Crop Science, Mustard Plant
Abstract

RNA interference (RNAi) is a promising, selective pest control technology based on the silencing of targeted genes mediated by the degradation of mRNA after the ingestion of double-stranded (ds) RNA. However, the identification of the best target genes remains a challenge, because large scale screening is only feasible in lab model systems and it remains unclear, to what degree such data can be transferred to pest species. Here, we report on our efforts to transfer target genes found in a lab model to the mustard leaf beetle, Phaedon cochleariae. The mustard leaf beetle can be reared easily and resource-efficient in large quantities all year round and is an established chrysomelid pest for higher throughput screening approaches in the crop protection industry. Mustard leaf beetle transcriptome sequencing and assembly revealed genes orthologous to those previously described as highly efficient RNAi targets in the model beetle Tribolium castaneum. First, we observed mortality after injection of dsRNA targeting the respective orthologous genes in 2nd instar mustard beetle larvae. Next, we adopted a robust, automated multi-well plate foliar RNAi screening procedure with 2nd instar larvae of the mustard leaf beetle to assess those genes. Indeed, foliar application and oral uptake of dsRNA targeting the same genes resulted in larval mortality as well. The most effective target genes with a strong (lethal) phenotype - at dsRNA doses as low as 300 ng/leaf disc (equal to 9.6 g/ha) - were srp54k, rop, αSNAP, rpn7 and rpt3. Rather limited effects were observed after application of dsRNA targeting cactus, shibire and PP-α, though they had previously been shown to be highly lethal in red flour beetle. Importantly, our experiments demonstrated that the overall efficacy pattern obtained after oral dsRNA application was well correlated with the results obtained after dsRNA injection. RT-qPCR confirmed significant target gene knock-down after normalization by employing three reference genes shown to be stably expressed across life stages. In summary, several RNAi targeted genes elicited a strong lethal phenotype and significant target gene knock-down after feeding, suggesting P. cochleariae as a potential coleopteran screening model for foliarly applied exogenous RNAi.

Published
2021

13. Toxicological and molecular profiling of insecticide resistance in a Brazilian strain of fall armyworm resistant to Bt Cry1 proteins

Author

Debora Boaventura, Ralf Nauen, Niklas Hamaekers, Frank Maiwald, and Benjamin Buer

Subjects
0106 biological sciences, Insecticides, resistance management, Bacillus thuringiensis, Spodoptera, fall armyworm, Zea mays, 01 natural sciences, Microbiology, cross‐resistance, Insecticide Resistance, Hemolysin Proteins, chemistry.chemical_compound, Bacterial Proteins, Animals, detoxification enzymes, Research Articles, Cross-resistance, Bacillus thuringiensis Toxins, biology, Organophosphate, Special Issue: Insect Control Agents ‐ Discovery and Neurotoxicology (ACS Fall 2019), General Medicine, Plants, Genetically Modified, biology.organism_classification, Endotoxins, 010602 entomology, Deltamethrin, chemistry, Insect Science, Chlorpyrifos, Fall armyworm, PEST analysis, Agronomy and Crop Science, Brazil, Research Article, 010606 plant biology & botany
Abstract

Background Spodoptera frugiperda, fall armyworm (FAW) is the major pest of maize in Brazil and has readily acquired field resistance to a broad range of synthetic insecticides and to Bacillus thuringiensis (Bt) insecticidal proteins expressed in important crops. This study aims to understand patterns of cross‐resistance in FAW by investigating the toxicological profile of a Bt‐resistant Brazilian strain (Sf_Des) in comparison to a Bt‐susceptible strain (Sf_Bra). Results Laboratory bioassays with 15 active substances of nine mode of action classes revealed that Sf_Des has a medium level of resistance to deltamethrin and chlorpyrifos. Very high cross‐resistance was observed among Cry1 toxins, but high susceptibility against Vip3A. Strain Sf_Des exhibited – depending on the substrate – up to 19‐fold increased cytochrome P450 activity in comparison to Sf_Bra. RNA‐Seq data support a major role of P450 enzymes in the detoxification of insecticides because we detected 85 P450 transcripts upregulated in Sf_Des. Quantitative reverse transcription polymerase chain reaction (RT‐qPCR) analysis confirmed that CYP9A‐like and CYP6B39 are significantly upregulated (>200‐fold) in Sf_Des in comparison to Sf_Bra strain. No target‐site mutation linked to pyrethroid resistance was detected, but mutations in the AChE linked to organophosphate resistance were observed in Sf_Des. A Gene Ontology (GO) analysis of differentially expressed genes (DEG) categorized most of them into the biological process category, involved in oxidation–reduction and metabolic processes. Conclusion Our results indicate that multiple/cross‐resistance mechanisms may have developed in the Sf_Des strain to conventional insecticides and Bt insecticidal proteins. The systematic toxicological analysis presented will help to guide recommendations for an efficient resistance management. © 2020 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., Spodoptera frugiperda, fall armyworm (FAW) is the major pest of maize in Brazil and has readily acquired field resistance to a broad range of synthetic insecticides and to Bacillus thuringiensis (Bt) insecticidal proteins expressed in important crops. This study aims to understand patterns of cross‐resistance in FAW by investigating the toxicological profile of a Bt‐resistant Brazilian strain (Sf_Des) in comparison to a Bt‐susceptible strain (Sf_Bra) at molecular and biochemical level.

Published
2020
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14. Identification and functional characterization of a novel acetyl-CoA carboxylase mutation associated with ketoenol resistance in Bemisia tabaci

Author

Thomas Van Leeuwen, Ralf Nauen, Gillian Hertlein, Chris Bass, Bettina Lueke, Pablo Bielza, John Vontas, Frank Maiwald, Vassilis Douris, Jamie Hopkinson, Kyriaki-Maria Papapostolou, and Anastasia Tsagkarakou

Subjects
Agriculture and Food Sciences, 0106 biological sciences, Insecticide resistance, BASE-LINE SUSCEPTIBILITY, TRIALEURODES-VAPORARIORUM, Health, Toxicology and Mutagenesis, Acetyl-CoA carboxylase, Whitefly, CROSS-RESISTANCE, Target-site mutation, medicine.disease_cause, Bemisia tabaci, 01 natural sciences, SPIROMESIFEN, Insecticide Resistance, 03 medical and health sciences, Lipid biosynthesis, medicine, Animals, MODE, Allele, CRISPR/Cas9, Cross-resistance, 030304 developmental biology, Genetics, 0303 health sciences, Mutation, biology, Australia, COENZYME, General Medicine, biology.organism_classification, Phenotype, 010602 entomology, SPIROTETRAMAT RESISTANCE, TARGET, Spain, SPIRODICLOFEN, Pyrosequencing, Ketoenols, Agronomy and Crop Science, Acetyl-CoA Carboxylase
Abstract

Insecticides of the tetronic/tetramic acid family (cyclic ketoenols) are widely used to control sucking pests such as whiteflies, aphids and mites. They act as inhibitors of acetyl-CoA carboxylase (ACC), a key enzyme for lipid biosynthesis across taxa. While it is well documented that plant ACCs targeted by herbicides have developed resistance associated with mutations at the carboxyltransferase (CT) domain, resistance to ketoenols in invertebrate pests has been previously associated either with metabolic resistance or with non-validated candidate mutations in different ACC domains. A recent study revealed high levels of spiromesifen and spirotetramat resistance in Spanish field populations of the whitefly Bemisia tabaci that was not thought to be associated with metabolic resistance. We confirm the presence of high resistance levels (up to > 640-fold) against ketoenol insecticides in both Spanish and Australian B. tabaci strains of the MED and MEAM1 species, respectively. RNAseq analysis revealed the presence of an ACC variant bearing a mutation that results in an amino acid substitution, A2083V, in a highly conserved region of the CT domain. F1 progeny resulting from reciprocal crosses between susceptible and resistant lines are almost fully resistant, suggesting an autosomal dominant mode of inheritance. In order to functionally investigate the contribution of this mutation and other candidate mutations previously reported in resistance phenotypes, we used CRISPR/Cas9 to generate genome modified Drosophila lines. Toxicity bioassays using multiple transgenic fly lines confirmed that A2083V causes high levels of resistance to commercial ketoenols. We therefore developed a pyrosequencing-based diagnostic assay to map the spread of the resistance alleles in field-collected samples from Spain. Our screening confirmed the presence of target-site resistance in numerous field-populations collected in Sevilla, Murcia and Almeria. This emphasizes the importance of implementing appropriate resistance management strategies to prevent or slow the spread of resistance through global whitefly populations.

Published
2020
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15. The COWVR Mission: Demonstrating the capability of a new generation of small satellite weather sensors

Author

Frank Maiwald, Sharmila Padmanabhan, Amarit Kitiyakara, Damon Russel, Lance Milligan, Shannon Brown, Richard Redick, Oliver Montes, Vin Bach, Phillip Walkemeyer, and Paolo Focardi

Subjects
Radiometer, 010504 meteorology & atmospheric sciences, Computer science, Microwave sensor, Microwave radiometer, 0211 other engineering and technologies, 02 engineering and technology, 01 natural sciences, Physics::Space Physics, Satellite, Physics::Atmospheric and Oceanic Physics, Microwave, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing
Abstract

The Compact Ocean Wind Vector Radiometer (COWVR) is new type of conical microwave sensor ideal for small satellite implementation. This paper provides an overview of the COWVR sensor, mission and provides perspectives for the future of this technology to enable low-cost sustainable passive microwave observations into the next decade.

Published
2017
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16. <scp>RNA</scp> ‐Seq transcriptome analysis to identify genes involved in metabolism‐based diclofop resistance in Lolium rigidum

Author

Mark-Christoph Ott, Johannes Herrmann, Stephen B. Powles, Qin Yu, Roland Beffa, Heping Han, Todd A. Gaines, Frank Maiwald, Andrea Figge, Roberto Busi, and Lothar Lorentz

Subjects
Genetics, education.field_of_study, Candidate gene, Contig, Population, food and beverages, RNA-Seq, Cell Biology, Plant Science, Biology, DNA sequencing, Transcriptome, Complementary DNA, Halogenated Diphenyl Ethers, Lolium, education, Gene, Herbicide Resistance
Abstract

Summary Weed control failures due to herbicide resistance are an increasing and worldwide problem that significantly affect crop yields. Metabolism-based herbicide resistance (referred to as metabolic resistance) in weeds is not well characterized at the genetic level. An RNA-Seq transcriptome analysis was used to find candidate genes that conferred metabolic resistance to the herbicide diclofop in a diclofop-resistant population (R) of the major global weed Lolium rigidum. A reference cDNA transcriptome (19 623 contigs) was assembled and assigned putative annotations. Global gene expression was measured using Illumina reads from untreated control, adjuvant-only control, and diclofop treatment of R and susceptible (S). Contigs that showed constitutive expression differences between untreated R and untreated S were selected for further validation analysis, including 11 contigs putatively annotated as cytochrome P450 (CytP450), glutathione transferase (GST), or glucosyltransferase (GT), and 17 additional contigs with annotations related to metabolism or signal transduction. In a forward genetics validation experiment, nine contigs had constitutive up-regulation in R individuals from a segregating F2 population, including three CytP450, one nitronate monooxygenase (NMO), three GST, and one GT. Principal component analysis using these nine contigs differentiated F2-R from F2-S individuals. In a physiological validation experiment in which 2,4-D pre-treatment induced diclofop protection in S individuals due to increased metabolism, seven of the nine genetically validated contigs were induced significantly. Four contigs (two CytP450, NMO, and GT) were consistently highly expressed in nine field-evolved metabolic resistant L. rigidum populations. These four contigs were strongly associated with the resistance phenotype and are major candidates for contributing to metabolic diclofop resistance.

Published
2014
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17. Ade novotranscriptome of European pollen beetle populations and its analysis, with special reference to insecticide action and resistance

Author

Ralf Nauen, Frank Maiwald, M. C. Ott, Corinna Schorn, Chris Bass, and Christoph T. Zimmer

Subjects
Genetics, Expressed sequence tag, Pyrethroid, Genomics, Biology, Resistance mutation, biology.organism_classification, Transcriptome, chemistry.chemical_compound, chemistry, Insect Science, Botany, PEST analysis, Pollen beetle, Molecular Biology, Meligethes aeneus
Abstract

The pollen beetle Meligethes aeneus is the most important coleopteran pest in European oilseed rape cultivation, annually infesting millions of hectares and responsible for substantial yield losses if not kept under economic damage thresholds. This species is primarily controlled with insecticides but has recently developed high levels of resistance to the pyrethroid class. The aim of the present study was to provide a transcriptomic resource to investigate mechanisms of resistance. cDNA was sequenced on both Roche (Indianapolis, IN, USA) and Illumina (LGC Genomics, Berlin, Germany) platforms, resulting in a total of ∼53 m reads which assembled into 43 396 expressed sequence tags (ESTs). Manual annotation revealed good coverage of genes encoding insecticide target sites and detoxification enzymes. A total of 77 nonredundant cytochrome P450 genes were identified. Mapping of Illumina RNAseq sequences (from susceptible and pyrethroid-resistant strains) against the reference transcriptome identified a cytochrome P450 (CYP6BQ23) as highly overexpressed in pyrethroid resistance strains. Single-nucleotide polymorphism analysis confirmed the presence of a target-site resistance mutation (L1014F) in the voltage-gated sodium channel of one resistant strain. Our results provide new insights into the important genes associated with pyrethroid resistance in M. aeneus. Furthermore, a comprehensive EST resource is provided for future studies on insecticide modes of action and resistance mechanisms in pollen beetle.

Published
2014
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18. Demonstrating a low-cost sustainable passive microwave sensor architecture: The Compact Ocean Wind Vector Radiometer Mission

Author

Frank Maiwald, Damon Russel, Sharmila Padmanabhan, Phillip Walkemeyer, Amarit Kitiyakara, Paolo Focardi, Vin Bach, Oliver Montes, Richard Redick, Lance Milligan, and Shannon Brown

Subjects
Radiometer, Computer science, Microwave sensor, Microwave radiometer, 0211 other engineering and technologies, 02 engineering and technology, Conical surface, Physics::Space Physics, Satellite, Architecture, Microwave radiometry, Physics::Atmospheric and Oceanic Physics, Microwave, 021101 geological & geomatics engineering, Remote sensing
Abstract

The Compact Ocean Wind Vector Radiometer (COWVR) is new type of conical sensor ideal for small satellite implementation. This paper provides an overview of the COWVR sensor, mission and provides perspectives for the future of this technology to enable low-cost sustainable passive microwave observations into the next decade.

Published
2016
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19. Unique features of a global human ectoparasite identified through sequencing of the bed bug genome

Author

Fang Zhu, Warren Booth, Zach N. Adelman, Benjamin A. Hottel, Huyen Dinh, Sebastian Wernig, Ameya D. Gondhalekar, Han Lin, Donna M. Muzny, Reinhard Predel, Abderrahman Khila, Antonin J.J. Crumière, Hugh M. Robertson, Christopher P. Childers, Monica F. Poelchau, Peter Nagui Refki, Klaus Reinhardt, Frank Maiwald, Jay D. Evans, Shwetha C. Murali, Kim C. Worley, Sandra L. Lee, Jing-Jiang Zhou, Stephen Richards, Amanda Dolan, Markus Friedrich, Corinna Schorn, Edward L. Vargo, Emily C. Jennings, Robert M. Waterhouse, Elise M. Szuter, Jeffery W. Jones, Iris M. Vargas Jentzsch, Andrew J. Rosendale, Elizabeth J. Duncan, José M. C. Ribeiro, Shannon Dugan, Nicolai Peschel, Yi Han, David Armisén, Christian Derst, Subba Reddy Palli, David A. Wheeler, Kapil R. Raje, Paul R. Johnston, Maria Emilia Santos, Kristen A. Panfilio, Mark-Christoph Ott, Chaoyang Zhao, Matthew T. Weirauch, Chien-Yueh Lee, Jacob M. Hendershot, Hemant Gujar, Valentina Resnik, Panagiotis Ioannidis, David R. Nelson, Coby Schal, M. Mohan, Evgeny M. Zdobnov, Joshua B. Benoit, Ralf Nauen, Omprakash Mittapalli, Pamela Menegazzi, Séverine Viala, Brittany F. Peterson, Harshavardhan Doddapaneni, Essia Sghaier, Richard W. Hagan, Michael E. Scharf, Christian Wegener, Daniel S.T. Hughes, Seung-Joon Ahn, J. Spencer Johnston, John H. Werren, Richard A. Gibbs, Wolfgang Blenau, Michelle A. E. Anderson, Jiaxin Qu, Hsu Chao, Jayendra Nath Shukla, Geoffrey M. Attardo, Ioannidis, Panagiotis, Waterhouse, Robert, Zdobnov, Evgeny, Entomology, and Massachusetts Institute of Technology. Computer Science and Artificial Intelligence Laboratory

Subjects
0301 basic medicine, Traumatic insemination, Bedbugs, Insecticides, Gene Transfer, General Physics and Astronomy, Ectoparasitic Infestations, Genome, Insecticide Resistance, Bed bug, Phylogenomics, ddc:576.5, Genetics, Multidisciplinary, Host-Parasite Interactions/genetics, Bedbugs/genetics, Biological sciences, Cimex lectularius, Sequence Analysis, Biotechnology, animal structures, Gene Transfer, Horizontal, Hematophagy, Science, Biology, Article, General Biochemistry, Genetics and Molecular Biology, DNA sequencing, Horizontal, Host-Parasite Interactions, 03 medical and health sciences, ddc:570, parasitic diseases, Insecticide Resistance/genetics, Animals, Humans, Obligate, Human Genome, fungi, Gene Transfer, Horizontal/genetics, General Chemistry, DNA, Feeding Behavior, Sequence Analysis, DNA, biology.organism_classification, 030104 developmental biology, Good Health and Well Being, Evolutionary biology
Abstract

The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host–symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome sequencing and annotation establish a solid foundation for future research on mechanisms of insecticide resistance, human–bed bug and symbiont–bed bug associations, and unique features of bed bug biology that contribute to the unprecedented success of C. lectularius as a human ectoparasite., The bed bug, Cimex lectularius, is a ubiquitous human ectoparasite with global distribution. Here, the authors sequence the genome of the bed bug and identify reductions in chemosensory genes, expansion of genes associated with blood digestion and genes linked to pesticide resistance.

Published
2016

20. The structure of carbodiimide, HNCNH

Author

Frank Lewen, Frank Maiwald, Sergei P. Belov, Gisbert Winnewisser, Manfred Winnewisser, and Wolfgang Jabs

Subjects
Biophysics, Analytical chemistry, Condensed Matter Physics, Spectral line, Isotopomers, chemistry.chemical_compound, Far infrared, chemistry, Computational chemistry, Cyanamide, Physical and Theoretical Chemistry, Chemical equilibrium, Molecular Biology, Carbodiimide, Millimetre wave
Abstract

An experimentally determined r s -type structure of HNCNH is reported: r NH = 1.0074 A, r CN = 1.2242 A, ∠HNC = 118.63°, ∠NCN = 170.63°, ∠HN ··· NH = 88.99°. The number of digits quoted allow for errors with two significant figures. In order to obtain these values we recorded rotational—torsional spectra of HN13CNH, H15NC15NH and DNCND, by using isotopically enriched cyanamide. A chemical equilibrium exists between carbodiimide, HNCNH, and the more stable isomer cyanamide, H2NCN, which strongly favours cyanamide (approximately 1:115 at 110 °C). The expensive C- and N-substituted isotopomers could only be investigated in the millimetre wave region, while for DNCND the far infrared spectrum between 10–350 cm−1 was also recorded. Rotational constants of the three isotopomers, as well as of the parent species, were determined by fitting the assigned spectral transitions to the Watson Hamiltonian in S reduction. Using fitting programs written by Schwendeman and Rudolph, r o, rs and rρ m structures of HNCNH wer...

Published
1999
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21. Factors Influencing T-DNA Transfer into Wheat and Barley Cells by Agrobacterium Tumefaciens

Author

Hans-Henning Steinbiss, Frank Maiwald, Petra Lorenzen, and Guang-Qin Guo

Subjects
Acetosyringone, biology, Strain (chemistry), Physiology, Agrobacterium, fungi, food and beverages, Plant physiology, Agrobacterium tumefaciens, biology.organism_classification, chemistry.chemical_compound, Horticulture, chemistry, Genetics, Hordeum vulgare, Cultivar, Agronomy and Crop Science, Gene
Abstract

Using an intron-GUS gene as a marker, various factors influencing the T-DNA transfer from Agrobacterium into wheat and barley cells were investigated. Among the 3 strains used, a supervirulent strain, EHA101(pIG121Hm), was found to be the most efficient. Calli derived from immature embryos of several cultivars (cvs) of wheat (Triticum aestivum L., cvs. Florida, Jinan 177 and Yuanfeng 6) and barley (Hordeum vulgare L., cv. Igri) were cocultivated with Agrobacterium, and their susceptibilities to agrobacteria infection differed greatly. Depending on their type and age, calli cultured on solid medium showed a high degree of variation in their competency for T-DNA transfer. However, efficient and highly reproducible GUS expression was observed in calli of wheat cv. Florida cultured in liquid medium. Acetosyringone (AS) was found to be vital for this process. The frequency of T-DNA transfer as measured by GUS expression was greatly increased by longer and repeated co-cultivation.

Published
1998
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22. Fabrication and test of terahertz extended interaction klystrons

Author

Khanh T. Nguyen, David Chernin, John H. Booske, N. Scott Barker, Mark Hyttinen, Edward L. Wright, Jeffrey P. Calame, Frank Maiwald, Monica Blank, Richard Dobbs, B. Steer, and Baruch Levush

Subjects
Fabrication, Materials science, Klystron, business.industry, Terahertz radiation, Amplifier, technology, industry, and agriculture, Terahertz metamaterials, law.invention, Photomixing, law, parasitic diseases, Optoelectronics, business
Abstract

The development of new terahertz power amplifiers at 0.67, 0.85 and 1.03 THz presents significant challenges in both design and fabrication. This paper describes the fabrication challenges and test results of a Beamstick and EIK at 0.67 THz.

Published
2011
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23. Detection of OH+ and H2O+ towards Orion KL

Author

Maryvonne Gerin, G. A. Blake, J. Stutzki, Shanshan Yu, S. Wang, Paul Hartogh, D. Johnstone, Thomas F. Giesen, Goutam Chattopadhyay, M. Perault, José Cernicharo, Ryszard Szczerba, Rudolf Schieder, Fabien Daniel, S. D. Lord, Jonas Zmuidzinas, Rafael Bachiller, Nathan R. Crockett, Alexandre Karpov, Neal R. Erickson, William B. Latter, John Gill, N. Harada, C. Joblin, P. Zaal, Marie-Lise Dubernet, Erich Schlecht, David A. Neufeld, P. F. Goldsmith, J. A. Murphy, René Liseau, Eric Herbst, C. Comito, Neil Trappe, H. Gupta, E. A. Bergin, A. C. A. Boogert, D. C. Lis, J. R. Goicoechea, Michael Olberg, Jacob Kooi, Jean-Michel Krieg, Frank Maiwald, W. Baechtold, Laurent Pagani, H. W. Yorke, T. A. Bell, F. F. S. van der Tak, Peter Schilke, Martin Emprechtinger, Cecilia Ceccarelli, Volker Ossenkopf, Stephan Schlemmer, Bengt Larsson, Paul B. Rimmer, W. D. Langer, P. J. Encrenaz, R. H. Lin, S.-L. Qin, N. Honingh, J. C. Pearson, Pierrick Martin, M. Salez, S. Cabrit, Emmanuel Caux, Thomas G. Phillips, Karl M. Menten, Sébastien Maret, Rene Plume, Patrick W. Morris, M. C. Diez-Gonzalez, Jesús Martín-Pintado, L. Nordh, Lorene Samoska, R. Güsten, Holger S. P. Müller, Charlotte Vastel, E. Falgarone, Gary J. Melnick, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Ohio State university Departement of Physic, Colombus, Ohio State University [Columbus] (OSU), Ohio State university Departement of Astronomy, Colombus, Ohio State university Departement of Chemistry, Colombus, foreign laboratories (FL), CERN [Genève], Ohio State Univ, Dept Phys, Columbus, OH 43210 USA, Ohio State Univ, Dept Astron & Chem, Columbus, OH 43210 USA, Ohio State University Dept Chemistry, Department of Astronomy [Ann Arbor], University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Millimeter-Wave Electronics Laboratory [ETH Zürich] (MWE), Department of Information Technology and Electrical Engineering [Zürich] (D-ITET), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Laboratoire Optimisation de la Conception et Ingénierie de l'Environnement (LOCIE), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Max Planck Institute for Radio Astronomy, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL), Laboratoire de Radioastronomie (LRA), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Cahill Center for Astronomy and Astrophysics, California Institute of Technology (CALTECH), Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V9E 2E7 Canada, Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, Laboratoire de Modélisation Multi-échelles des Combustibles (LM2C), Service d'Etudes de Simulation du Comportement du combustibles (SESC), Département d'Etudes des Combustibles (DEC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Département d'Etudes des Combustibles (DEC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Max-Planck-Institut für Radioastronomie (MPIFR), Infrared Processing and Analysis Center (IPAC), Onsala Space Observatory, Chalmers University of Technology [Göteborg], Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), SRON Netherlands Institute for Space Research (SRON), Department of Physics and Astronomy [Calgary], University of Calgary, I. Physikalisches Institut [Köln], Universität zu Köln = University of Cologne, Laboratoire de Didactique André Revuz (LDAR (EA_4434)), Université d'Artois (UA)-Université Paris Diderot - Paris 7 (UPD7)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, A.M.Obukhov Institute of Atmospheric Physics (IAP), Russian Academy of Sciences [Moscow] (RAS), Harvard University [Cambridge]-Smithsonian Institution, Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA, CALTECH, Ctr Infrared Proc & Anal, Pasadena, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Universität zu Köln, Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université Paris Diderot - Paris 7 (UPD7)-Université d'Artois (UA), Max-Planck-Institut für Sonnensystemforschung (MPS), Department of Physics [Columbus], Department of Astronomy [Columbus], Department chemistry and Biochemistry [Columbus], Department of Physics and Astronomy [Baltimore], Johns Hopkins University (JHU), Smithsonian Institution-Harvard University [Cambridge], Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Instituto Nacional de Técnica Aeroespacial (INTA), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Observatorio de Yebes, Instituto Geografico Nacional (IGN), Laboratoire de Physique Moleculaire pour l'Atmosphere et l'Astrophysique (LPMAA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid 28850, Spain, Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction de l'Energie Nucléaire (CEA-DEN), Univ Cologne, Inst Phys 1, D-50937 Cologne, Germany, Univ Cologne, Inst Phys 1, and Astronomy

Subjects
[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], HERSCHEL OBSERVATIONS, Analytical chemistry, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, LINE, Astrophysics, LASER MAGNETIC-RESONANCE, 7. Clean energy, 01 natural sciences, ISM: abundances, outflows, Ion, STAR-FORMATION, REGION, NEBULA, Ionization, 0103 physical sciences, Absorption (logic), 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, SPECTROSCOPY, astrochemistry, Astronomy and Astrophysics, INTERSTELLAR H3O+, Astrophysics - Astrophysics of Galaxies, DIFFUSE CLOUDS, molecular processes, [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], 13. Climate action, Space and Planetary Science, COMET-KOHOUTEK, Astrophysics of Galaxies (astro-ph.GA), stars: winds, submillimeter: ISM, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Order of magnitude, line: identification
Abstract

We report observations of the reactive molecular ions OH$^+$, H$_2$O$^+$, and H$_3$O$^+$ towards Orion KL with Herschel/HIFI. All three $N=1-0$ fine-structure transitions of OH$^+$ at 909, 971, and 1033GHz and both fine-structure components of the doublet {\it ortho}-H$_2$O$^+$ $1_{11}-0_{00}$ transition at 1115 and 1139GHz were detected; an upper limit was obtained for H$_3$O$^+$. OH$^+$ and H$_2$O$^+$ are observed purely in absorption, showing a narrow component at the source velocity of 9 kms$^{-1}$, and a broad blueshifted absorption similar to that reported recently for HF and {\it para}-H$_{2}^{18}$O, and attributed to the low velocity outflow of Orion KL. We estimate column densities of OH$^+$ and H$_2$O$^+$ for the 9 km s$^{-1}$ component of $9 \pm 3 \times 10^{12}$cm$^{-2}$ and $7 \pm 2 \times 10^{12}$cm$^{-2}$, and those in the outflow of $1.9 \pm 0.7 \times 10^{13}$cm$^{-2}$ and $1.0 \pm 0.3 \times 10^{13}$cm$^{-2}$. Upper limits of $2.4\times 10^{12}$cm$^{-2}$ and $8.7\times 10^{12}$cm$^{-2}$ were derived for the column densities of {\it ortho} and {\it para}-H$_3$O$^+$ from transitions near 985 and 1657GHz. The column densities of the three ions are up to an order of magnitude lower than those obtained from recent observations of W31C and W49N. The comparatively low column densities may be explained by a higher gas density despite the assumption of a very high ionization rate., 5 pages, 1 figure. Accepted to and to be published in the Herschel HIFI special issue of A\&A Letters

Published
2010
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24. High power local oscillator sources for 1-2 THz

Author

John Ward, Erich Schlecht, Alain Maestrini, Frank Maiwald, Goutam Chattopadhyay, John Gill, Choonsup Lee, Imran Mehdi, Robert Lin, and Bertrand Thomas

Subjects
Physics, Heterodyne, business.industry, Terahertz radiation, Local oscillator, Schottky diode, Power (physics), law.invention, Telescope, Optics, law, Broadband, business, Diode
Abstract

Recent results from the Heterodyne Instrument for Far-Infrared (HIFI) on the Herschel Space Telescope have confirmed the usefulness of high resolution spectroscopic data for a better understanding of our Universe. This paper will explore the current status of tunable local oscillator sources beyond HIFI and provide demonstration of how power combining of GaAs Schottky diodes can be used to increase both power and upper operating frequency for heterodyne receivers. Availability of power levels greater than 1 watt in the W-band now makes it possible to design a 1900 GHz source with more than 100 microwatts of expected output power.

Published
2010
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25. Herschel/HIFI measurements of the ortho/para ratio in water towards Sagittarius B2(M) and W31C

Author

Benjamin Godard, Jonas Zmuidzinas, T. A. Bell, John H. Black, Frank Maiwald, Martin Emprechtinger, Maryvonne Gerin, C. Joblin, S. Wang, M. Perault, Patrick Hennebelle, Gary J. Melnick, Shanshan Yu, Peter Schilke, S. D. Lord, Paule Sonnentrucker, P. Hily-Blant, D. Johnstone, F. Boulanger, M. R. Schmidt, D. Teyssier, Raquel Monje, Alexandre Karpov, Jacob Kooi, Stephan Schlemmer, M. Salez, Peter G. Martin, David A. Neufeld, P. F. Goldsmith, Neil Trappe, M. De Luca, Karl M. Menten, Robert Kołos, F. F. S. van der Tak, Javier R. Goicoechea, Emmanuel Caux, Sébastien Maret, S.-L. Qin, Thomas R. Geballe, Cecile Gry, Neal R. Erickson, Rene Plume, Harold W. Yorke, Jesús Martín-Pintado, E. Falgarone, J. A. Murphy, Sylvie Cabrit, M. Kaźmierczak, Nathan R. Crockett, Eric Herbst, Jacek Krełowski, Charlotte Vastel, José Cernicharo, Holger S. P. Müller, P. Zaal, John C. Pearson, Carina M. Persson, Patrick W. Morris, Marie-Lise Dubernet, H. Gupta, P. J. Encrenaz, Rudolf Schieder, Fabien Daniel, Audrey Coutens, Adwin Boogert, Geoffrey A. Blake, Cecilia Ceccarelli, Edwin A. Bergin, J. Stutzki, Dariusz C. Lis, Thomas F. Giesen, Emmanuel Dartois, Bhaswati Mookerjea, Thomas G. Phillips, Laurent Pagani, Volker Ossenkopf, C. Comito, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Astronomy, and Faure, Alexandre

Subjects
Experimental Physics, FOS: Physical sciences, Astrophysics, 01 natural sciences, ISM: abundances, COLOGNE DATABASE, OXYGEN, 0103 physical sciences, ABSORPTION, Sagittarius B2, 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, AMMONIA, CDMS, Line-of-sight, SPECTROSCOPY, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], astrochemistry, ASTRONOMY, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM: molecules, molecular processes, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), MOLECULAR CLOUDS, VAPOR, submillimeter: ISM, SUBMILLIMETER
Abstract

We present Herschel/HIFI observations of the fundamental rotational transitions of ortho- and para-H$_2^{16}$O and H$_2^{18}$O in absorption towards Sagittarius~B2(M) and W31C. The ortho/para ratio in water in the foreground clouds on the line of sight towards these bright continuum sources is generally consistent with the statistical high-temperature ratio of 3, within the observational uncertainties. However, somewhat unexpectedly, we derive a low ortho/para ratio of $2.35 \pm 0.35$, corresponding to a spin temperature of $\sim$27~K, towards Sagittarius~B2(M) at velocities of the expanding molecular ring. Water molecules in this region appear to have formed with, or relaxed to, an ortho/para ratio close to the value corresponding to the local temperature of the gas and dust., Accepted for publication in A&A, HIFI Special Issue; 5 pages, 3 figures

Published
2010
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26. The Herschel-Heterodyne Instrument for the Far-Infrared (HIFI)

Author

Brian Jackson, B. Kopf, R. Bieber, R. Güsten, A. M. di Giorgio, J. A. Stern, Holger S. P. Müller, B. J. van Leeuwen, G. S. Liu, R. Orfei, Neal R. Erickson, R. Lai, B. Delforges, Wolfgang Wild, Christian Leinz, O. Coeur-Joly, J. Desbat, David Teyssier, S. D. Lord, Karl Jacobs, Bruce Bumble, Lorene Samoska, M. Rataj, R. H. Lin, Dominicus Kester, M. Salez, X. Tielens, Alexandre Karpov, Paolo Saraceno, K. Edwards, R. Huisman, A. Megej, K. F. Schuster, Michel Fich, L. Dubbeldam, Serguei Cherednichenko, H. Golstein, Christian Monstein, J. A. Murphy, C. van Baaren, Victor Belitsky, P. Planesas, E. Natale, Michael Olberg, Lorenzo Piazzo, T. Peacock, Martin Eggens, Emmanuel Caux, W. A. Hatch, Neil Trappe, Hubregt J. Visser, Herbert Zirath, Jaap Evers, S. Phillip-May, Alain Maestrini, Hamid Javadi, Jacob Kooi, Th. de Graauw, F. Schmülling, E. C. Honingh, C. McCoey, J. C. Pearson, W. Luinge, I. Lopez-Fernandez, W. M. Laauwen, M. Michalska, Bengt Larsson, S. Wulff, John Gill, René Liseau, Volker Ossenkopf, Colin Borys, B. Kruizenga, Rafael Teipen, C. Kramer, A. Cros, H. Goulooze, P. Cais, W. Nowosielski, Goutam Chattopadhyay, M. Stokroos, Rafael Bachiller, F. Zwart, C. Gal, Piotr Orleanski, J. Kawamura, H. Smit, O. Siebertz, H. Aarts, Francesco Nuzzolo, L. Meinsma, Jonas Zmuidzinas, R. Assendorp, D. A. Beintema, H. van de Stadt, Jesús Martín-Pintado, G. de Lange, Ryszard Szczerba, Erich Schlecht, R. Higgins, Christophe Risacher, Patrick W. Morris, H. Jacobs, Christopher Jarchow, Willem Jellema, Pieter Dieleman, Todd Gaier, B. Franke, J. Stutzki, Imran Mehdi, Th. Klein, Harald Franz Arno Merkel, T. Finn, M. Justen, P.R. Wesselius, M. Ciechanowicz, T. M. Klapwijk, Hans-Joachim Wunsch, C. Comito, P. Zaal, Erik L. Kollberg, C. Diez-Gonzalez, T. den Boggende, John Ward, Jian-Rong Gao, Pasquale Cerulli-Irelli, C. Kasemann, T. Kuhn, Frank Helmich, K. Wildeman, Henry G. LeDuc, L. Ravera, Frank Maiwald, Y. Delorme, D. Moratschke, F. Schlöder, J. M. Krieg, M. Olbrich, A. Marston, Juan Daniel Gallego, P.-P. Kooiman, E. Steinmetz, T. Gunsing, A. Naber, M. Melchior, Geert Keizer, M. Schultz, I. Peron, S. Gauffre, C. K. Wafelbakker, N. Whyborn, M. Krause, T. Tils, Alexander Loose, A. de Jonge, Pieter R. Roelfsema, Rudolf Schieder, M. Caris, S. Glenz, A. Barcia, W. Baechtold, Paul Hartogh, R. Shipman, Adwin Boogert, Arnold O. Benz, Thomas G. Phillips, California Institute of Technology (CALTECH), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Sciences et Technologies - Bordeaux 1, Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Department of Microtechnology and Nanoscience (MC2), Chalmers University of Technology [Gothenburg, Sweden], Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Dept Pathol & Microbiol, Université de Montréal (UdeM)-Faculté de médecine vétérinaire, Leibniz Institute for Crystal Growth, Leibniz Institute, Technische Universität Darmstadt (TU Darmstadt), Instituto de RadioAstronomía Milimétrica (IRAM), Centre National de la Recherche Scientifique (CNRS), Institut für Festkörpertheorie, Westfälische Wilhelms-Universität Münster (WWU), Institute of Molecular Medicine and Cell Research (ZBMZ), University of Freiburg [Freiburg], Onsala Space Observatory, Chalmers University of Technology [Göteborg], ESO, European Southern Observatory (ESO), Istituto di Fisica dello Spazio Interplanetario (IFSI), Consiglio Nazionale delle Ricerche (CNR), Max Planck Institute for Meteorology (MPI-M), Institut für Chemie und Dynamik der Geosphäre - Troposphäre (ICG-2), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association-Helmholtz-Gemeinschaft = Helmholtz Association, Herschel Science Center [Madrid], European Space Astronomy Centre (ESAC), European Space Agency (ESA)-European Space Agency (ESA), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), École normale supérieure - Paris (ENS-PSL), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Technische Universität Darmstadt - Technical University of Darmstadt (TU Darmstadt), Westfälische Wilhelms-Universität Münster = University of Münster (WWU), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA), TNO Industrie en Techniek, and Astronomy

Subjects
Experimental Physics, Local oscillator, Observatories, Orbits, general [Submillimeter], 01 natural sciences, 7. Clean energy, spectroscopic [Techniques], law.invention, Far infrared, Spectrographs, law, spectrographs [Instrumentation], 010303 astronomy & astrophysics, instrumentation: spectrographs, Physics, Spectrometers, submillimeter: general, Bolometers, Correlators, methods: observational, infrared: general, Heterodyne, Frequency band, Submillimeter: generals, Instantaneous phase, Radio spectrum, Optics, Mixers (machinery), 0103 physical sciences, Frequency bands, observational [Methods], 010306 general physics, Remote sensing, techniques: spectroscopic, Spectrometer, business.industry, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Bolometer, generals [Submillimeter], Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Launching, general [Infrared], Space and Planetary Science, Heterodyning, Instruments, business
Abstract

International audience; Aims: This paper describes the Heterodyne Instrument for the Far-Infrared (HIFI) that was launched onboard ESA's Herschel Space Observatory in May 2009. Methods: The instrument is a set of 7 heterodyne receivers that are electronically tuneable, covering 480-1250 GHz with SIS mixers and the 1410-1910 GHz range with hot electron bolometer (HEB) mixers. The local oscillator (LO) subsystem comprises a Ka-band synthesizer followed by 14 chains of frequency multipliers and 2 chains for each frequency band. A pair of auto-correlators and a pair of acousto-optical spectrometers process the two IF signals from the dual-polarization, single-pixel front-ends to provide instantaneous frequency coverage of 2 × 4 GHz, with a set of resolutions (125 kHz to 1 MHz) that are better than 0.1 km s-1. Results: After a successful qualification and a pre-launch TB/TV test program, the flight instrument is now in-orbit and completed successfully the commissioning and performance verification phase. The in-orbit performance of the receivers matches the pre-launch sensitivities. We also report on the in-orbit performance of the receivers and some first results of HIFI's operations. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Published
2010
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27. THz instrumentation for the Herschel Space Observatory's heterodyne instrument for far infrared

Author

W. A. Hatch, Imran Mehdi, Frank Maiwald, Michael Paquette, John C. Pearson, Robert Lin, Lorene Samoska, David P. Miller, Robert Ferber, Mary Wells, K. T. Liao, Thomas G. Phillips, Sander Weinreb, James Velebir, J. Kawamura, Alain Maestrini, William Chun, John Gill, Alexandre Karpov, Alejandro Peralta, John Ward, Hamid Javadi, Bradley P. Finamore, Jeffrey A. Stern, Neal R. Erickson, Robert J. Dengler, Henry G. LeDuc, Bruce Bumble, David Pukala, Todd Gaier, Gerald Swift, Edward M. Luong, Raymond Tsang, Jonas Zmuidzinas, Erich Schlecht, Zmuidzinas, Jonas, Holland, Wayne S., and Withington, Stafford

Subjects
Heterodyne, Physics, Optics, Intermediate frequency, Far infrared, Terahertz radiation, business.industry, Amplifier, Local oscillator, High-electron-mobility transistor, Telecommunications, business, Varicap
Abstract

The Heterodyne Instrument for Far Infrared (HIFI) on ESA's Herschel Space Observatory utilizes a variety of novel RF components in its five SIS receiver channels covering 480-1250 GHz and two HEB receiver channels covering 1410-1910 GHz. The local oscillator unit will be passively cooled while the focal plane unit is cooled by superfluid helium and cold helium vapors. HIFI employs W-band GaAs amplifiers, InP HEMT low noise IF amplifiers, fixed tuned broadband planar diode multipliers, high power W-bapd Isolators, and novel material systems in the SIS mixers. The National Aeronautics and Space Administration through the Jet Propulsion Laboratory is managing the development of the highest frequency (1119-1250 GHz) SIS mixers, the local oscillators oscillators for the three highest frequency receivers as well as W-band power amplifiers, high power W-band isolators, varactor diode devices for all high frequency multipliers and InP HEMT components for all the receiver channels intermediate frequency amplifiers. The NASA developed components represent a significant advancement in the available performance. This paper presents an update of the performance and the current state of development.

Published
2004
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28. Terahertz frequency receiver instrumentation for Herschel's heterodyne instrument for far infrared (HIFI)

Author

John Gill, Alexandre Karpov, Huei Wang, Lorene Samoska, Jonas Zmuidzinas, Erich Schlecht, Neal R. Erickson, David P. Miller, Dennis G. Harding, Frank Maiwald, J. A. Stern, Imran Mehdi, Dave Pukala, W. A. Hatch, Yun Chung, Bruce Bumble, Todd Gaier, William R. McGrath, Robert Ferber, John Ward, J. Kawamura, Richard Lai, S.C. Martin, Alain Maestrini, John C. Pearson, Jerry Swift, Thomas G. Phillips, Henry G. LeDuc, and Mather, John C.

Subjects
Heterodyne, Optical amplifier, Physics, Optics, Far infrared, Intermediate frequency, Terahertz radiation, business.industry, Amplifier, Local oscillator, business, Varicap
Abstract

The Heterodyne Instrument for Far Infrared (HIFI) on ESA's Herschel Space Observatory is comprised of five SIS receiver channels covering 480-1250 GHz and two HEB receiver channels covering 1410-1910 GHz. Two fixed tuned local oscillator sub-bands are derived from a common synthesizer to provide the front-end frequency coverage for each channel. The local oscillator unti will be passively cooled while the focal plane unit is cooled by superfluid helium and cold helium vapors. HIFI employs W-band GaAs amplifiers, InP HEMT low noise IF amplifiers, fixed tuned broadband planar diode multipliers, and novel material systems in the SIS mixtures. The National Aeronautics and Space Administration's Jet Propulsion Laboratory is managing the development of the highest frequency (1119-1250 GHz) SIS mixers, the highest frequency (1650-1910 GHz) HEB mixers, local oscillators for the three highest frequency receivers as well as W-band power amplifiers, varactor diode devices for all high frequency multipliers and InP HEMT components for all the receiver channels intermediate frequency amplifiers. The NASA developed components represent a significant advancement in the available performance. The current state of the art for each of these devices is presented along with a programmatic view of the development effort.

Published
2003

29. Terahertz frequency multiplier chains based on planar Schottky diodes

Author

Alain Maestrini, Erich Schlecht, Imran Mehdi, Goutam Chattopadhyay, Dave Pukala, John C. Pearson, and Frank Maiwald

Subjects
Heterodyne, Physics, business.industry, Terahertz radiation, Local oscillator, Frequency multiplier, Schottky diode, law.invention, Optics, law, Optoelectronics, business, Waveguide, Diode, Electronic circuit
Abstract

The Herschel Space Observatory (HSO), an ESA cornerstone mission with NASA contribution, will enable a comprehensive study of the galactic and the extra galactic universe. At the heart of this exploration are ultra sensitive coherent detectors for high-resolution spectroscopy. Successful operation of these receivers is predicated on providing a sufficiently powerful local oscillator (LO) source. Historically, a versatile space qualified LO source for frequencies beyond 500 GHz has been difficult if not impossible. This paper will focus on the effort under way to develop, build, characterize and qualify a LO chain to 1200 GHz (Band 5 on HSO) that is based on planar GaAs diodes mounted in waveguide circuits. State-of-the-art performance has been obtained from a three-stage (×2×2×3) multiplier chain that can provide a peak output power of 120 μW (1178 GHz) at room temperature and a peak output power of 190 μW at 1183 GHZ when cooled to 113 K. Implementation of this LO source for the Heterodyne Instrument for Far Infrared (HIFI) one of three instruments on HSO will be discussed in detail.

Published
2003
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30. Frequency multiplier response to spurious signals and its effect on local oscillator systems in millimeter and submillimeter wavelengths

Author

Robert J. Dengler, Erich Schlecht, John C. Pearson, Goutam Chattopadhyay, Imran Mehdi, and Frank Maiwald

Subjects
Heterodyne, Physics, business.industry, Amplifier, Frequency multiplier, Local oscillator, Astrophysics::Instrumentation and Methods for Astrophysics, Harmonic balance, Optics, Extremely high frequency, business, Passband, Varicap, Astrophysics::Galaxy Astrophysics
Abstract

Broadband fixed-tuned frequency multipliers in conjunction with broadband power amplifiers driven by frequency synthesizers are often used as local oscillator (LO) sources in the millimeter and submillimeter wave heterodyne instruments. At these frequencies the multipliers use Gallium Arsenide (GaAs) based Schottky varactor diodes as the nonlinear element, and like most other harmonic generators are susceptible to spurious signal interference. The state-of-the-art LO sources in the millimeter and submillimeter wavelengths use MMIC power amplifiers producing in excess of 250 mW of output power in the 100 GHz range, and they are used to drive the subsequent multiplier stages. Because of the high input power environment and the presence of noise in the system, the multipliers become vulnerable to spurious signal interference, either through the bias lines or through the RF port. As the spurious signals propagate through the multiplier chain, they generate inter-modulation products which might fall in the passband of the heterodyne instrument and seriously degrade its performance. The issues of frequency multiplier response to spurious signal interference and its effect on local oscillator performance in millimeter and submillimeter wave heterodyne instruments are investigated. Results of numerical harmonic balance simulations and laboratory experiments are presented here, and are found to show good agreement.

Published
2003
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31. Fabrication of 200 to 2700 GHz multiplier devices using GaAs and metal membranes

Author

Erich Schlecht, P. Smith, Alain Maestrini, A. Fung, Peter H. Siegel, J. Bruston, B. Nakamura, Frank Maiwald, Imran Mehdi, and S.C. Martin

Subjects
Fabrication, Materials science, business.industry, Electrical engineering, Integrated circuit, law.invention, Gallium arsenide, chemistry.chemical_compound, chemistry, Etching (microfabrication), law, Optoelectronics, business, Lithography, Waveguide, Electron-beam lithography, Diode
Abstract

Multiplier device fabrication techniques have been developed to enable robust implementation of monolithic circuits well into the THz frequency range. To minimize the dielectric loading of the waveguides, some circuits are realized entirely on a 3 /spl mu/m thick GaAs membrane with metal beamleads acting as RF probes and DC contact points. Other designs retain some thicker GaAs as a support and handling structure, allowing a membrane of bare metal or thin GaAs to be suspended across an input or output waveguide. Extensive use is made of selective etches, both reactive ion (RIE) and wet chemical, to maintain critical dimensions. Electron beam (e-beam) lithography provides the small contact areas required at the highest frequencies. Planar multiplier circuits for 200 GHz to 2700 GHz have been demonstrated using a variety of metal and GaAs membrane configurations made available by these fabrication techniques.

Published
2002
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32. Development of 200-GHz to 2.7-THz multiplier chains for submillimeter-wave heterodyne receivers

Author

Peter H. Siegel, Frank Maiwald, Imran Mehdi, R. P. Smith, J. Bruston, John C. Pearson, Alain Maestrini, Erich Schlecht, and S.C. Martin

Subjects
Physics, Heterodyne, business.industry, Terahertz radiation, Amplifier, Superheterodyne receiver, Schottky diode, Integrated circuit, law.invention, Optics, law, Extremely high frequency, Optoelectronics, business, Diode
Abstract

Several astrophysics and Earth observation space missions planned for the near future will require submillimeter-wave heterodyne radiometers for spectral line observations. One of these, the Far InfraRed and Submillimeter Telescope will perform high-sensitivity, high-resolution spectroscopy in the 400 to 2700 GHz range with a seven channel super- conducting heterodyne receiver complement. The local oscillators for all these channels will be constructed around state-of-the-art GaAs power amplifiers in the 71 to 115 GHz range, followed by planar Schottky diode multiplier chains. The Jet Propulsion Laboratory is responsible for developing the multiplier chains for the 1.2, 1.7, and 2.7 THz bands. This paper will focus on the designs and technologies being developed to enhance the current state- of-the-art, which is based on discrete planar or whisker contacted GaAs Schottky diode chips mounted in waveguide blocks. We are proposing a number of new planar integrated circuit and device topologies to implement multipliers at these high frequencies. Approaches include substrateless, framed and frameless GaAs membrane circuitry with single, and multiple planar integrated Schottky diodes. Circuits discussed include 200 and 400 GHz doublers, a 1.2 THz tripler and a 2.4 THz doubler. Progress to date, with the implications of this technology development for future Earth and space science instruments, is presented.

Published
2000
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33. Demonstration of a room temperature 2.48–2.75 THz coherent spectroscopy source

Author

Choonsup Lee, Paul F. Goldsmith, Robert Lin, Bertrand Thomas, Frank Maiwald, John Gill, Goutam Chattopadhyay, Alain Maestrini, John C. Pearson, Shanshan Yu, Peter H. Siegel, Imran Mehdi, John Ward, Brian J. Drouin, Erich Schlecht, Jet Propulsion Laboratory, California Institute of Technology (JPL), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), and Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Spectrometer, business.industry, Terahertz radiation, Local oscillator, Amplifier, Terahertz spectroscopy and technology, Nuclear magnetic resonance, Optoelectronics, Continuous wave, Wideband, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Coherent spectroscopy, business, Instrumentation
Abstract

International audience; We report the first demonstration of a continuous wave coherent source covering 2.48-2.75 THz, with greater than 10% instantaneous tuning bandwidth and having 1-14 muW of output power at room temperature. This source is based on a 91.8-101.8 GHz synthesizer followed by a power amplifier and three cascaded frequency triplers. It demonstrates for the first time that purely electronic solid-state sources can generate a useful amount of power in a region of the electromagnetic spectrum where lasers (solid state or gas) were previously the only available coherent sources. The bandwidth, agility, and operability of this THz source have enabled wideband, high resolution spectroscopic measurements of water, methanol, and carbon monoxide with a resolution and signal-to-noise ratio unmatched by any other existing system, providing new insight in the physics of these molecules. Furthermore, the power and optical beam quality are high enough to observe the Lamb-dip effect in water. The source frequency has an absolute accuracy better than 1 part in 1012 and the spectrometer achieves sub-Doppler frequency resolution better than 1 part in 108. The harmonic purity is better than 25 dB. This source can serve as a coherent signal for absorption spectroscopy, a local oscillator for a variety of heterodyne systems and can be used as a method for precision control of more powerful but much less frequency agile quantum mechanical terahertz sources.

Published
2011
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34. The CHESS spectral survey of star forming regions: Peering into the protostellar shock L1157-B1. II. Shock dynamics

Author

K. Schuster, M. Benedettini, F. Gueth, Gary J. Melnick, F. F. S. van der Tak, G. de Lange, S. D. Lord, D. C. Lis, P. J. Encrenaz, S. Pacheco, Emmanuel Caux, Asunción Fuente, Brunella Nisini, N. Crimier, Patrick Hennebelle, M. H. D. van der Wiel, Serena Viti, G. A. Blake, Valentine Wakelam, Peter Schilke, Paolo Saraceno, P. Hily-Blant, José Cernicharo, Frank Maiwald, Karine Demyk, Colin Borys, Friedrich Wyrowski, C. Kramer, E. Falgarone, T. Jacq, Berengere Parise, A. Klotz, A. Lorenzani, M. Salez, A. C. A. Boogert, P. Siegel, Imran Mehdi, Jesús Martín-Pintado, Rafael Bachiller, Cecilia Ceccarelli, David A. Neufeld, P. F. Goldsmith, Aggm Tielens, E. A. Bergin, Sébastien Maret, Laurent Pagani, Charlotte Vastel, T. A. Bell, Volker Ossenkopf, Th. Henning, J. C. Pearson, Thomas G. Phillips, Sylvie Cabrit, Bertrand Lefloch, Juan R. Pardo, Alain Baudry, Harold W. Yorke, Alain Castets, J. Stutzki, Aurore Bacmann, Bengt Larsson, Audrey Coutens, Frank Helmich, C. Comito, Claudine Kahane, Mihkel Kama, Y. Delorme, Maryvonne Gerin, Paola Caselli, Claudio Codella, J. H. Wunsch, Adam Walters, W. D. Langer, Carsten Dominik, R. Lai, Sandrine Bottinelli, Eric Herbst, Low Energy Astrophysics (API, FNWI), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Kapteyn Astronomical Institute, Centro de Investigaciones Biológicas (CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Roma (OAR), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Laboratoire Optimisation de la Conception et Ingénierie de l'Environnement (LOCIE), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Laboratoire de Radioastronomie (LRA), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Ohio State University [Columbus] (OSU), Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), Istituto di Fisica dello Spazio Interplanetario (IFSI), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Max-Planck-Institut für Radioastronomie (MPIFR), Instituto de RadioAstronomía Milimétrica (IRAM), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, École normale supérieure - Paris (ENS Paris), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1, Civilisations atlantiques & Archéosciences (C2A), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ministère de la Culture et de la Communication (MCC)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), Université de Nantes (UN)-Université de Nantes (UN), Harvard University [Cambridge]-Smithsonian Institution, Université Nice Sophia Antipolis (... - 2019) (UNS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), Consiglio Nazionale delle Ricerche (CNR), Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Osservatorio di Astrofisica di Roma (OAR), Ministère de la Culture et de la Communication (MCC)-Centre National de la Recherche Scientifique (CNRS)-Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Faure, Alexandre, Université de Nantes - UFR Histoire, Histoire de l'Art et Archéologie (UFR HHAA), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture et de la Communication (MCC), and Smithsonian Institution-Harvard University [Cambridge]

Subjects
DATABASE, Astronomy, LINE EMISSION, Flux, Astrophysics, ISM: ets and outflows, 01 natural sciences, 7. Clean energy, ISM: individual objects: L1157, 0103 physical sciences, PROGRAM, Protostar, 14. Life underwater, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, QB, Line (formation), Physics, stars: formation, 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], ISM: molecules, EVOLUTION, Shock (mechanics), 13. Climate action, Space and Planetary Science, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, 1157 MOLECULAR OUTFLOW, Outflow, METHANOL, Magnetohydrodynamics, SUBMILLIMETER, Order of magnitude, Excitation
Abstract

International audience; Context. The outflow driven by the low-mass class 0 protostar L1157 is the prototype of the so-called chemically active outflows. The bright bowshock B1 in the southern outflow lobe is a privileged testbed of magneto-hydrodynamical (MHD) shock models, for which dynamical and chemical processes are strongly interdependent. Aims: We present the first results of the unbiased spectral survey of the L1157-B1 bowshock, obtained in the framework of the key program “Chemical HErschel Surveys of star forming regions” (CHESS). The main aim is to trace the warm and chemically enriched gas and to infer the excitation conditions in the shock region. Methods: The CO 5-4 and o-H2O 110-101 lines have been detected at high-spectral resolution in the unbiased spectral survey of the HIFI-band 1b spectral window (555-636 GHz), presented by Codella et al. in this volume. Complementary ground-based observations in the submm window help establish the origin of the emission detected in the main-beam of HIFI and the physical conditions in the shock. Results: Both lines exhibit broad wings, which extend to velocities much higher than reported up to now. We find that the molecular emission arises from two regions with distinct physical conditions : an extended, warm (100 K), dense (3 × 105 cm-3) component at low-velocity, which dominates the water line flux in Band 1; a secondary component in a small region of B1 (a few arcsec) associated with high-velocity, hot (>400 K) gas of moderate density ((1.0-3.0) × 104 cm-3), which appears to dominate the flux of the water line at 179μm observed with PACS. The water abundance is enhanced by two orders of magnitude between the low- and the high-velocity component, from 8 × 10-7 up to 8 × 10-5. The properties of the high-velocity component agree well with the predictions of steady-state C-shock models. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Published
2010
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35. Application of cascaded frequency multiplication to molecular spectroscopy

Author

Frank Maiwald, Brian J. Drouin, and John C. Pearson

Subjects
Physics, Spectrometer, Electromagnetic spectrum, Infrared, business.industry, Amplifier, symbols.namesake, Optics, Fourier transform, symbols, Data analysis, Absorption (electromagnetic radiation), business, Spectroscopy, Instrumentation
Abstract

Laboratory molecular spectroscopy provides the basis for interpretation of atmospheric, planetary, and astrophysical data gathered by remote sensing. Laboratory studies of atomic and molecular signatures across the electromagnetic spectrum provide high-precision, quantitative data used to interpret the observed environment from remote measurements. Historically, the region of the spectrum above 500 GHz has been relatively unexplored due to atmospheric absorption and technical difficulties generating and detecting radiation. Laboratory spectroscopy at these frequencies has traditionally involved measurement of one or two absorption features and relied on fitting of models to the limited data. We report a new spectrometer built around a computer-controlled commercial synthesizer and millimeter-wave module driving a series of amplifiers followed by a series of wide-bandwidth frequency doublers and triplers. The spectrometer provides the ability to rapidly measure large pieces of frequency space with higher resolution, accuracy, and sensitivity than with Fourier transform infrared techniques. The approach is simple, modular, and requires no custom-built electronics or high voltage and facilitates the use of infrared data analysis techniques on complex submillimeter spectra.

Published
2005
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36. CASIMIR: A high resolution, far-IR/submm spectrometer for airborne astronomy

Author

Sean Lin, Frank Maiwald, Robert Lin, Simon J. E. Radford, Imran Mehdi, Alexandre Karpov, David P. Miller, John Ward, F. Rice, Michael L. Edgar, Martin Emprechtinger, Jonas Zmuidzinas, McLean, Ian S., Ramsay, Suzanne K., and Takami, Hideki

Subjects
Heterodyne, Physics, Infrared astronomy, Spectrometer, Terahertz radiation, business.industry, Stratospheric Observatory for Infrared Astronomy, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Radio spectrum, Optics, Observational astronomy, Far infrared, business, Astrophysics::Galaxy Astrophysics
Abstract

CASIMIR, the Caltech Airborne Submillimeter Interstellar Medium Investigations Receiver, is a far-infrared and submillimeter heterodyne spectrometer, being developed for the Stratospheric Observatory For Infrared Astronomy, SOFIA. CASIMIR will use newly developed superconducting-insulating-superconducting (SIS) mixers. Combined with the 2.5 m mirror of SOFIA, these detectors will allow observations with high sensitivity to be made in the frequency range from 500 GHz up to 1.4 THz. Initially, at least 5 frequency bands in this range are planned, each with a 4-8 GHz IF passband. Up to 4 frequency bands will be available on each flight and bands may be swapped readily between flights. The local oscillators for all bands are synthesized and tuner-less, using solid state multipliers. CASIMIR also uses a novel, commercial, field-programmable gate array (FPGA) based, fast Fourier transform spectrometer, with extremely high resolution, 22000 (268 kHz at 6 GHz), yielding a system resolution > 10 6 . CASIMIR is extremely well suited to observe the warm, ≈ 100K, interstellar medium, particularly hydrides and water lines, in both galactic and extragalactic sources. We present an overview of the instrument, its capabilities and systems. We also describe recent progress in development of the local oscillators and present our first astronomical observations obtained with the new type of spectrometer.

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