scholarly journals M 31's Molecular Arms at All Scales to Below 10 pc

2001 ◽  
Vol 205 ◽  
pp. 352-355 ◽  
Author(s):  
N. Neininger ◽  
Ch. Nieten ◽  
M. Guélin ◽  
H. Ungerechts ◽  
R. Lucas ◽  
...  
Keyword(s):  
High Resolution ◽  
Angular Resolution ◽  
Molecular Gas ◽  
Data Set ◽  
Unique Data ◽  
Small Scales ◽  
M 31 ◽  
Star Formation Regions ◽  
The Individual ◽  
First Time

I present a unique data set for the study of molecular gas in galaxies: a complete, high-resolution survey of the CO in M 31 and additional local studies. The fully sampled survey has an angular resolution of 23 FWHM and the interferometric data attain the pc-scale with sub-arcsecond resolution. For the first time it is now possible to study large and small scales in conjunction. Thus we are able to derive the global structure and study the links down to the individual cloud complexes and star formation regions.

Algorithms for automated montage synthesis of images from laser-scanning confocal microscopes

1995 ◽  
Vol 53 ◽  
pp. 650-651
Author(s):  
D. E. Becker
Keyword(s):  
Image Analysis ◽  
High Resolution ◽  
Laser Scanning ◽  
Cell Counting ◽  
Wide Area ◽  
Data Set ◽  
Computational Synthesis ◽  
Automated Cell Counting ◽  
Partial View ◽  
The Individual

An efficient, robust, and widely-applicable technique is presented for computational synthesis of high-resolution, wide-area images of a specimen from a series of overlapping partial views. This technique can also be used to combine the results of various forms of image analysis, such as segmentation, automated cell counting, deblurring, and neuron tracing, to generate representations that are equivalent to processing the large wide-area image, rather than the individual partial views. This can be a first step towards quantitation of the higher-level tissue architecture. The computational approach overcomes mechanical limitations, such as hysterisis and backlash, of microscope stages. It also automates a procedure that is currently done manually. One application is the high-resolution visualization and/or quantitation of large batches of specimens that are much wider than the field of view of the microscope.The automated montage synthesis begins by computing a concise set of landmark points for each partial view. The type of landmarks used can vary greatly depending on the images of interest. In many cases, image analysis performed on each data set can provide useful landmarks. Even when no such “natural” landmarks are available, image processing can often provide useful landmarks.

scholarly journals The Molecular Outflow and CO Bullets in HH111

1997 ◽  
Vol 182 ◽  
pp. 141-152 ◽  
Author(s):  
J. Cernicharo ◽  
R. Neri ◽  
Bo Reipurth
Keyword(s):  
High Velocity ◽  
Angular Resolution ◽  
High Angular Resolution ◽  
Molecular Gas ◽  
Kinetic Temperature ◽  
Low Velocity ◽  
Molecular Outflow ◽  
Hh Objects ◽  
Physical Phenomena ◽  
First Time

We present high angular resolution observations of the molecular outflow associated with the optical jet and HH objects of the HH111 system. Interferometric observations in the CO J =2–1 and J =1–0 lines of the high velocity bullets associated with HH111 are presented for the first time. The molecular gas in these high velocity clumps has a moderate kinetic temperature and a mass of a few 10–4 M⊙ per bullet. We favor the view that HH jets and CO bullets, which represent different manifestations of the same physical phenomena, are driving the low-velocity molecular outflow.

scholarly journals The ALMA-PILS survey: gas dynamics in IRAS 16293−2422 and the connection between its two protostars

2019 ◽  
Vol 626 ◽  
pp. A93 ◽  
Author(s):  
M. H. D. van der Wiel ◽  
S. K. Jacobsen ◽  
J. K. Jørgensen ◽  
T. L. Bourke ◽  
L. E. Kristensen ◽  
...  
Keyword(s):  
Gas Dynamics ◽  
Angular Resolution ◽  
Spatial Scales ◽  
Morphological Structure ◽  
Molecular Gas ◽  
Evolutionary Stage ◽  
Data Set ◽  
Envelope Material ◽  
Molecular Lines ◽  
Structure Lead

Context. The majority of stars form in binary or higher order systems. The evolution of each protostar in a multiple system may start at different times and may progress differently. The Class 0 protostellar system IRAS 16293–2422 contains two protostars, “A” and “B”, separated by ~600 au and embedded in a single, 104 au scale envelope. Their relative evolutionary stages have been debated. Aims. We aim to study the relation and interplay between the two protostars A and B at spatial scales of 60 au up to ~103 au. Methods. We selected molecular gas line transitions of the species CO, H2CO, HCN, CS, SiO, and C2H from the ALMA-PILS spectral imaging survey (329–363 GHz) and used them as tracers of kinematics, density, and temperature in the IRAS 16293–2422 system. The angular resolution of the PILS data set allows us to study these quantities at a resolution of 0.5′′ (60 au at the distance of the source). Results. Line-of-sight velocity maps of both optically thick and optically thin molecular lines reveal: (i) new manifestations of previously known outflows emanating from protostar A; (ii) a kinematically quiescent bridge of dust and gas spanning between the two protostars, with an inferred density between 4 × 104 cm−3 and ~3 × 107 cm−3; and (iii) a separate, straight filament seemingly connected to protostar B seen only in C2H, with a flat kinematic signature. Signs of various outflows, all emanating from source A, are evidence of high-density and warmer gas; none of them coincide spatially and kinematically with the bridge. Conclusions. We hypothesize that the bridge arc is a remnant of filamentary substructure in the protostellar envelope material from which protostellar sources A and B have formed. One particular morphological structure appears to be due to outflowing gas impacting the quiescent bridge material. The continuing lack of clear outflow signatures unambiguously associated to protostar B and the vertically extended shape derived for its disk-like structure lead us to conclude that source B may be in an earlier evolutionary stage than source A.

scholarly journals Giving Intention Versus Giving Behavior: How Differently Do Satisfaction, Trust, and Commitment Relate to Them?

2019 ◽  
Vol 48 (5) ◽  
pp. 1023-1044 ◽  
Author(s):  
Jen Shang ◽  
Adrian Sargeant ◽  
Kathryn Carpenter
Keyword(s):  
Indirect Effects ◽  
Effect Sizes ◽  
Categorical Variables ◽  
Direct And Indirect Effects ◽  
Group Level ◽  
Data Set ◽  
Individual Level ◽  
Unique Data ◽  
First Time ◽  
Practical Implications

This research quantifies for the first time in the literature how strong the direct and indirect relationships are between satisfaction, trust, and commitment and giving intention versus giving behavior. We constructed a unique data set of over 17,000 donors from five large charities. We applied the latest mediation framework for categorical variables from consumer behavior. We found that at a group level, most of the direct and indirect effects that exist between satisfaction, trust, commitment, and giving intention also exist between these factors and giving behavior, but the effect sizes are between 3 to 8 times larger in modeling giving intentions than in modeling giving behavior. When giving intention and giving behavior are matched at an individual level, all group-level findings are replicated. In addition, we found 27% of the donors with no intention to give, actually gave. Theoretical, empirical, methodological, and practical implications are discussed.

scholarly journals CHIMPS2: survey description and 12CO emission in the Galactic Centre

2020 ◽  
Vol 498 (4) ◽  
pp. 5936-5951 ◽  
Author(s):  
D J Eden ◽  
T J T Moore ◽  
M J Currie ◽  
A J Rigby ◽  
E Rosolowsky ◽  
...  
Keyword(s):  
High Resolution ◽  
Milky Way ◽  
Angular Resolution ◽  
Galactic Plane ◽  
Galactic Centre ◽  
Data Set ◽  
Valuable Data ◽  
Future Studies ◽  
James Clerk Maxwell ◽  
Array Receiver

ABSTRACT The latest generation of Galactic Plane surveys is enhancing our ability to study the effects of galactic environment upon the process of star formation. We present the first data from CO Heterodyne Inner Milky Way Plane Survey 2 (CHIMPS2). CHIMPS2 is a survey that will observe the Inner Galaxy, the Central Molecular Zone (CMZ), and a section of the Outer Galaxy in 12CO, 13CO, and C18O $(J = 3\rightarrow 2)$ emission with the Heterodyne Array Receiver Program on the James Clerk Maxwell Telescope (JCMT). The first CHIMPS2 data presented here are a first look towards the CMZ in 12CO J = 3 → 2 and cover ${-}3^{\circ }\, \le \, \ell \, \le \, 5^{\circ }$ and $\mid {b} \mid \, \le \, 0{_{.}^{\circ}} 5$ with angular resolution of 15 arcsec, velocity resolution of 1 km s−1, and rms $\Delta \, T_A ^\ast =$ 0.58 K at these resolutions. Such high-resolution observations of the CMZ will be a valuable data set for future studies, whilst complementing the existing Galactic Plane surveys, such as SEDIGISM, the ${Herschel}$ infrared Galactic Plane Survey, and ATLASGAL. In this paper, we discuss the survey plan, the current observations and data, as well as presenting position–position maps of the region. The position–velocity maps detect foreground spiral arms in both absorption and emission.

The problem of heterogeneity between protected geographical indications: a meta-analysis

2018 ◽  
Vol 120 (12) ◽  
pp. 2843-2856 ◽  
Author(s):  
Daniel Leufkens
Keyword(s):  
Willingness To Pay ◽  
Meta Analysis ◽  
Data Set ◽  
Content Type ◽  
Marginal Willingness To Pay ◽  
Great Heterogeneity ◽  
Long Time ◽  
Heterogeneity Analysis ◽  
The Individual ◽  
First Time

Purpose For a long time the European geographical indication (GI) regulation has been of great interest to economists and policymakers. To justify exclusive European regulation it is necessary to prove the positive value of a GI quality signal (i.e. label), which is often achieved by quantifying its monetary value for the consumers. But even though a large number of literary contributions already deal with this question, they lack the evaluation of overall effect sizes for the GI label. The purpose of this paper is, therefore, to quantify and evaluate the overall marginal consumer willingness to pay for the European GI label. Design/methodology/approach To reach this aim, a meta-analysis is used for which a literature survey had been carried out in order to determine the GI label effects (LEs). In addition to previous works, this paper not only includes a meta-analysis, but also implements a heterogeneity analysis to distinguish between the LEs of individual GI standards. To eliminate study- and product-specific determinants of heterogeneity, moderator variables are used. Findings The empirical results indicate that consumers have a highly significant and positive marginal willingness to pay for GIs. However, the marginal willingness to pay differs significantly between the individual GI standards and indicates great heterogeneity between the protected products. Originality/value As an extension to previous studies and meta-analysis; this paper includes the most extensive GIs meta-data set so far, and conducts for the first time an independent heterogeneity analysis to distinguish between the LEs of individual GI standards and implements a moderator analysis to eliminate study- and product-specific determinants of heterogeneity from the GI effects.

High-resolution direct observation of the carbon-cage structure of C60 buckyballs

1992 ◽  
Vol 25 (5) ◽  
pp. 657-660 ◽  
Author(s):  
A. V. Narlikar ◽  
S. B. Samanta ◽  
P. K. Dutta ◽  
L. S. Grigoryan ◽  
A. K. Majumdar
Keyword(s):  
High Resolution ◽  
Sample Surface ◽  
Cage Structure ◽  
Carbon Cage ◽  
Fullerene Derivatives ◽  
Electrically Conducting ◽  
Field Gradients ◽  
Scanning Tunnelling ◽  
The Individual ◽  
First Time

In C60 films containing higher fullerene derivatives and having electrically conducting islands, it has been possible for the first time to observe, using high resolution scanning tunnelling electron microscopy (STM), the individual carbon cage of C60 buckyballs forming a f.c.c. lattice on a silver-coated glass substrate. The observed images of the molecule are surprisingly distinct and not smeared out, indicating their ambient-temperature reorientational motion to be pinned. The possible causes of the freezing are: (i) the presence of higher fullerene derivatives; (ii) changes in the electronic structure of the films due to interaction and proximity of Ag atoms; and (iii) the pinning of the molecules by the presence of large electric field gradients between the STM tip and the sample surface, a factor which, in addition, is considered responsible for the distortion observed in the buckyball images.

Deep onshore reflection seismic imaging of the chalk group strata using a 45 kg accelerated weight-drop and combined recording systems with dense receiver spacing

Geophysics ◽  
2019 ◽  
Vol 84 (4) ◽  
pp. B259-B268 ◽  
Author(s):  
Janina Kammann ◽  
Alireza Malehmir ◽  
Bojan Brodic ◽  
Mattia Tagliavento ◽  
Lars Stemmerik ◽  
...  
Keyword(s):  
High Resolution ◽  
Upper Cretaceous ◽  
Seismic Profile ◽  
Borehole Data ◽  
Seismic Line ◽  
Data Set ◽  
Reflection Seismic ◽  
Weight Drop ◽  
Excellent Control ◽  
First Time

The Chalk Group forms important hydrocarbon reservoirs offshore and water aquifers onshore Denmark. Within a day of fieldwork, a 450 m long reflection seismic profile was acquired onshore in an area in southeast Denmark, where the Chalk Group extends almost to the surface and is approximately 900 m thick. The main objective of the study was to image the complete Chalk Group in high resolution and to study the origin of reflectivity within the different chalk units. A 45 kg accelerated weight-drop source, in combination with dense receiver spacing using microelectromechanical sensors mounted on a streamer and 48 planted geophones, was used for data acquisition. The profile runs subparallel to the cliffs of Stevns, and the recorded signal reaches the base of the Chalk Group at approximately 600 ms. The fully cored 443 m-deep Stevns-1 borehole, which is located at the recorded seismic line, provides excellent control on lithologic and facies changes. Comparison with the borehole data demonstrates that our seismic data set provides a high-resolution image of the internal layering of the Chalk Group. We find that the internal reflection coefficients of the Chalk Group are, in general, small based on wireline-log data. However, the reflected amplitudes are just big enough to be recorded with the receiver setup used, even from the pure chalk beds of the Chalk Group. The reflectivity seen on the high-resolution seismic profile is influenced by occurrences of clay-enriched chalk layers. Flint bands consisting of numerous flint nodules are a characteristic of the uppermost part of the Chalk Group at Stevns. The flint nodules appear to produce significant scattering of the seismic signals, and flint-rich layers appear with diffuse internal reflectivity characteristics. Outcrop-scale mound structures in Danian and Upper Cretaceous outcrops are for the first time seismically resolved.

scholarly journals High Resolution Observations of Molecular Gas in the Outflow of M 82

2004 ◽  
Vol 217 ◽  
pp. 314-315
Author(s):  
Fabian Walter ◽  
Axel Weiss ◽  
Nick Scoville
Keyword(s):  
High Resolution ◽  
Mechanical Energy ◽  
Opening Angle ◽  
Molecular Gas ◽  
Molecular Outflow ◽  
Outflow Velocity ◽  
Line Splitting ◽  
Total Mechanical Energy ◽  
First Time ◽  
Absorption Features

We present a high-resolution (3.6“, 70 pc) CO(1-0) mosaic of the molecular gas in M 82 covering an area of 2.5'x3.5’ (2.8 kpc x 3.9 kpc) obtained with the OVRO millimeter interferometer. The observations reveal the presence of huge amounts of molecular gas (> 70% of the total molecular mass, Mtot ≈ 1.3 × 109M⊙) outside the central 1 kpc disk. Molecular streamers are detected in and below M 82's disk out to distances from the center of ~1.7 kpc. Some of these streamers are well correlated with optical absorption features; they form the basis of some of the prominent tidal HI features around M 82. This provides evidence that the molecular gas within M 82's optical disk is disrupted by the interaction with M 81. Molecular gas is found in M 82's outflow/halo, reaching distances up to 1.2 kpc below the plane; CO line-splitting has been detected for the first time in the outflow. The maximum outflow velocity is ~ 230 km s−1; we derive an opening angle of ~ 55° for the molecular outflow cone. The total amount of gas in the outflow is > 3 × 108 M⊙ and its kinetic energy is of order 1055 erg, about one percent of the estimated total mechanical energy input of M 82's starburst. Our study implies that extreme starburst environments can move significant amounts of molecular gas in to a galaxy's halo (and even to the intergalactic medium).

High-resolution CO images of the Galactic central molecular zone

2019 ◽  
Vol 71 (Supplement_1) ◽  
Author(s):  
Sekito Tokuyama ◽  
Tomoharu Oka ◽  
Shunya Takekawa ◽  
Yuhei Iwata ◽  
Shiho Tsujimoto ◽  
...  
Keyword(s):  
High Resolution ◽  
Spatial Resolution ◽  
Detailed Comparison ◽  
Molecular Gas ◽  
Data Sets ◽  
Radio Observatory ◽  
James Clerk Maxwell ◽  
The Galaxy ◽  
Special Area ◽  
First Time

Abstract We performed Nyquist-sampled mapping observations of the central molecular zone of our Galaxy in the J = 1–0 lines of CO, 13CO, and C18O using the 45 m telescope at the Nobeyama Radio Observatory. The newly obtained data sets were an improvement by a factor of four in spatial resolution of the CO data previously obtained with the same telescope 22 years ago, providing the highest angular resolution CO atlas of this special area of the Galaxy. The data cover the area: −0${^{\circ}_{.}}$8 ≤ l ≤ +1${^{\circ}_{.}}$4 and −0${^{\circ}_{.}}$35 ≤ b ≤ +0${^{\circ}_{.}}$35 with a 15″ beamwidth. Total intensity ratios for CO J = 3–2/J = 1–0, 13CO/CO J = 1–0 and C18O/13CO J = 1–0, are 0.70 ± 0.06, 0.12 ± 0.01, and 0.14 ± 0.01, respectively. The high-resolution CO images show the fine structure of the molecular gas and enable us to identify a number of compact clouds with broad velocity widths, i.e., high-velocity compact clouds. We conducted a detailed comparison of our CO J = 1–0 data with the CO J = 3–2 data obtained with the James Clerk Maxwell Telescope to derive the distribution and kinematics of the highly excited gas. Three, out of four, of the previously identified high CO J = 3–2/J = 1–0 ratio areas at l = +1${^{\circ}_{.}}$3, 0${^{\circ}_{.}}$0, and −0${^{\circ}_{.}}$4 were confirmed with a higher spatial resolution. In addition to these, we identified several very compact, high CO J = 3–2/J = 1–0 spots with broad velocity widths for the first time. These are candidates for accelerated gas in the vicinity of invisible, point-like massive objects.

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