Herschel Measurements of Molecular Oxygen in Orion

We report observations of three rotational transitions of molecular oxygen (O_2) in emission from the H_2 Peak 1 position of vibrationally excited molecular hydrogen in Orion. We observed the 487 GHz, 774 GHz, and 1121 GHz lines using the Heterodyne Instrument for the Far Infrared on the Herschel Space Observatory, having velocities of 11 km s^(–1) to 12 km s^(–1) and widths of 3 km s^(–1). The beam-averaged column density is N(O_2) = 6.5 × 10^(16) cm^(–2), and assuming that the source has an equal beam-filling factor for all transitions (beam widths 44, 28, and 19"), the relative line intensities imply a kinetic temperature between 65 K and 120 K. The fractional abundance of O_2 relative to H_2 is (0.3-7.3) × 10^(–6). The unusual velocity suggests an association with a ~5" diameter source, denoted Peak A, the Western Clump, or MF4. The mass of this source is ~10 M_⊙ and the dust temperature is ≥150 K. Our preferred explanation of the enhanced O_2 abundance is that dust grains in this region are sufficiently warm (T ≥ 100 K) to desorb water ice and thus keep a significant fraction of elemental oxygen in the gas phase, with a significant fraction as O_2. For this small source, the line ratios require a temperature ≥180 K. The inferred O_2 column density ≃5 × 10^(18) cm^(–2) can be produced in Peak A, having N(H_2) ≃4 × 10^(24) cm^(–2). An alternative mechanism is a low-velocity (10-15 km s^(–1)) C-shock, which can produce N(O_2) up to 10^(17) cm^(–2)

Dust emission in the Sagittarius B2 molecular cloud core

A model is presented for the dust emission from the Sagittarius B2 molecular cloud core which reproduces the observed spectrum between 30 and 1300 micron, as well as the distribution of the emission at 1300 micron. The model is based on the assumption that Sgr B2(N) continuum source is located behind the dust cloud associated with Sgr B2(M) continuum source. The fact that Sgr B2(N) is stronger at 1300 micron can be attributed to a local column density maximum at the position of this source. Absence of a 53 micron emission peak at the position of Sgr B2(N) suggests that the luminosity of the north source is lower than that of the middle source

Herschel/HIFI line surveys: Discovery of interstellar chloronium (H_2Cl^+)

Prior to the launch of Herschel, HCl was the only chlorine-containing molecule detected in the interstellar medium (ISM). However, chemical models have identified chloronium, H_2Cl^+, as a relatively abundant species that is potentially detectable. H_2Cl^+ was predicted to be most abundant in the environments where the ultraviolet radiation is strong: in diffuse clouds, or near the surfaces of dense clouds illuminated by nearby O and B stars. The HIFI instrument on Herschel provided the first detection of H_2Cl^+ in the ISM. The 2_(12)-1_(01) lines of ortho- H_2^(35)Cl^+ and ortho- H_2^(37)Cl^+ were detected in absorption toward NGC 6334I, and the 1_(11)-0_(00) transition of para- H_2^(35)Cl^+ was detected in absorption toward NGC 6334I and Sgr B2(S). The derived HCl/H_2Cl^+ column density ratios, ∼1-10, are within the range predicted by models of diffuse and dense Photon Dominated Regions (PDRs). However, the observed H_2Cl^+ column densities, in excess of 10^(13) cm^(−2), are significantly higher than the model predictions. These observations demonstrate the outstanding spectroscopic capabilities of HIFI for detecting new interstellar molecules and providing key constraints for astrochemical models

The Sagittarius B2 molecular cloud : an extreme case of a galactic center giant molecular cloud.

AstronomyDoctor of Philosophy (PhD

Water: from clouds to planets

Results from recent space missions, in particular Spitzer and Herschel, have lead to significant progress in our understanding of the formation and transport of water from clouds to disks, planetesimals, and planets. In this review, we provide the underpinnings for the basic molecular physics and chemistry of water and outline these advances in the context of water formation in space, its transport to a forming disk, its evolution in the disk, and finally the delivery to forming terrestrial worlds and accretion by gas giants. Throughout, we pay close attention to the disposition of water as vapor or solid and whether it might be subject to processing at any stage. The context of the water in the solar system and the isotopic ratios (D/H) in various bodies are discussed as grounding data point for this evolution. Additional advances include growing knowledge of the composition of atmospheres of extra-solar gas giants, which may be influenced by the variable phases of water in the protoplanetary disk. Further, the architecture of extra-solar systems leaves strong hints of dynamical interactions, which are important for the delivery of water and subsequent evolution of planetary systems. We conclude with an exploration of water on Earth and note that all of the processes and key parameters identified here should also hold for exoplanetary systems.Comment: 24 pages, 13 figures; updated exoplanet observations references. Accepted for publication as a chapter in Protostars and Planets VI, University of Arizona Press (2014), eds. H. Beuther, R. Klessen, C. Dullemond, Th. Hennin

The CARMA-NRO Orion Survey

We present the first results from a new, high-resolution ^(12)CO(1–0), ^(13)CO(1–0), and C^(18)O(1–0) molecular-line survey of the Orion A cloud, hereafter referred to as the CARMA-NRO Orion Survey. CARMA observations have been combined with single-dish data from the Nobeyama 45 m telescope to provide extended images at about 0.01 pc resolution, with a dynamic range of approximately 1200 in spatial scale. Here we describe the practical details of the data combination in uv space, including flux scale matching, the conversion of single-dish data to visibilities, and joint deconvolution of single-dish and interferometric data. A Δ-variance analysis indicates that no artifacts are caused by combining data from the two instruments. Initial analysis of the data cubes, including moment maps, average spectra, channel maps, position–velocity diagrams, excitation temperature, column density, and line ratio maps, provides evidence of complex and interesting structures such as filaments, bipolar outflows, shells, bubbles, and photo-eroded pillars. The implications for star formation processes are profound, and follow-up scientific studies by the CARMA-NRO Orion team are now underway. We plan to make all the data products described here generally accessible; some are already available at https://dataverse.harvard.edu/dataverse/CARMA-NRO-Orion

MODYFIKACJE METODY P&O ŚLEDZENIA MAKSYMALNEGO PUNKTU MOCY DLA PANELU FOTOWOLTAICZNEGO

Perturbation and Observe method for maximum power point tracking is presented in this paper. Three method modifications have been proposed, which allow satisfying tracking efficiency, even for very fast and noisy irradiance changes.W artykule przedstawiono metodę zaburzania i obserwacji P&O do śledzenia maksymalnego punktu mocy. Zaproponowano trzy modyfikacje metody, dzięki którym efektywność śledzenia jest zadowalająca, nawet dla bardzo szybkich oraz zaszumionych zmian irradiancji

Gross value added in services - a case study of the sea port in Szczecin

The aim of the paper is to determine the size and structure of the Gross Value Added (GVA) generated by the supply of services in Szczecin seaport. Correlations, multipliers, and elas­ticities between different port services are indicated in the paper. The GVA is an economic measure of the size of generated production. In seaports, it expresses the value of the generated and delivered flow of services of warehousing and cargo handling, securing the safe movement and mooring of ships in port and their technical and commercial support, of accessibility to port infrastructure for in port manufacturers and port users, of organization, planning and coordination of processes of cargo and transportation units handling inside the port and at other nodes of the transportation chain. The scope of the research at Szczecin seaport included four groups of activities, namely: - cargo handling companies; - sea transportation support companies, including the ones supplying port shipping services (navi- gation, pilotage, and towage), dredging and underwater works (carried within the inner port basins), sea rescue, and other maritime services; - sea transportation agencies supplying services of port and maritime forwarding, shipbuilding brokerage, ship agencies, customs, maritime consulting and expertize, cargo stowage and secur­ing aboard the ship, cargo expertise and inspection, and other services (logistics); and - sea port authorities. GVA has been calculated by subtracting the value of the intermediate consumption from the gross output of the port sector companies. The intermediate consumption consists of the value of con­sumed materials and energy, external services, and the rest of the by nature costs of business entities. The GVA calculation has been based on the statistical data obtained from the Centre of Maritime Statistics at the Statistical Office in Szczecin

Port logistic park - a case study

In the port management, apart from logistic centers, warehouse and storage centers and distribution centers there appear new organizational forms of logistic activity in the form of ware­house-production centers called logistic parks. The aim of this paper is to present issues connected with the development of activities performed at port logistic parks, to determine quantitative aspects of development of business activities, to point at problems related to transport services to logistic parks. For the descriptive part the comparative method was used, and for the quantitative aspects of a logistic park's activities statistical methods were used, which allowed for assessment of storage turnover and of traffic volumes. The analytic studies were conducted on the example of a logistic park that was being under development within the area of the maritime port in Szczecin

Statistical estimation and prediction of Annual Average Daily Traffic (AADT) on the first/last mile road sections in the Port of Szczecin

Deepening the fairway Świnoujście-Szczecin to a depth of 12.5 m will improve access to the port of Szczecin from the sea. Larger vessels will be able to call at the port of Szczecin and thus the current trends in cargo turnover will probably change. To make it possible, it is also necessary to invest in improving port access from the mainland. In the article the authors present estimates and forecasts of the annual average daily traffic of vehicles (AADT) on national road no. 10 (DK 10) and access roads to the port of Szczecin (so called the "last mile" sections). Estimation was based on the author's own traffic research carried out in September-October 2016 as part of Feasibility Study for the project Modernization of the access roads to the port o/Szczecin: reconstruction of the transport system in the area of Miedzyodrze implemented by the city of Szczecin