First Results from Observations of the Moon by Means of a Polarimeter

1962 ◽  
Vol 14 ◽  
pp. 463-467
Author(s):  
V. P. Dzhapiashvili ◽  
L. V. Ksanfomaliti
Keyword(s):  
Observational Data ◽  
Direct Measurement ◽  
Polarization Plane ◽  
Light Polarization ◽  
Degree Of Polarization ◽  
The Moon ◽  
First Results ◽  
Image Position ◽  
Additional Reduction

Until recently, no instrument was available for a direct measurement of the degree of light polarization and of the angle determining the position of the polarization plane. The degree of polarization was calculated by formulafrom the measurements of the maximum Φmaxand minimum Φminlight fluxes through an analyzer. A laborious additional reduction of the observational data was necessary for obtaining the final characteristics of light polarization.

scholarly journals 79. Radio emission from the moon and the nature of its surface

1957 ◽  
Vol 4 ◽  
pp. 406-407 ◽  
Author(s):  
V. S. Troitzky ◽  
S. E. Khaikin
Keyword(s):  
Radio Emission ◽  
Attenuation Coefficient ◽  
Wave Length ◽  
Degree Of Polarization ◽  
Lunar Phase ◽  
Radio Waves ◽  
The Moon ◽  
Subsolar Point ◽  
Image Position ◽  
Academy Of Sciences

A theoretical study of the integral radio emission of the moon, measured at the wave-length of 3·2 cm. (Zelinskaja and Troitzky[1]; Kajdanovsky, Turusbekov and Khaikin[2]), was carried out at the Gorky radio astronomical station ‘Zimenky’ and at the Physical Institute of the Academy of Sciences of the U.S.S.R. The following expression for the average radio temperature of the entire lunar disk, as a function of the lunar phase, Ωt, was obtained (Troitzky, 1954) [3]: Here tan ξ = δ/(1 + δ) and δ = β/κ, where β is the attenuation coefficient of the thermal wave, κ the power attenuation coefficient of the radio wave. Further, Tm = 374°K. is the temperature of the subsolar point, Tn is the temperature at the lunar midnight, Θ = Tm – Tn and k0 is the reflexion coefficient of radio waves for vertical incidence (k0 ≈ 0–1). The numerical coefficients in equation (1) were obtained as a result of averaging the Fresnel reflexion coefficients over the whole disk. The degree of polarization of the total radio emission was calculated and was found to be about 4 %.

Direct Measurement of the Gravitational Effect of the Moon

Physics ◽  
1933 ◽  
Vol 4 (4) ◽  
pp. 162-163 ◽  
Author(s):  
Kenneth Hartley
Keyword(s):  
Direct Measurement ◽  
Gravitational Effect ◽  
The Moon

ROTATIONAL PROPERTIES OF MICRO-SLABS DRIVEN BY LINEARLY-POLARIZED LIGHT

2005 ◽  
Vol 14 (03) ◽  
pp. 375-382 ◽  
Author(s):  
CHIH-LANG LIN ◽  
IRÈNE WANG ◽  
MARC PIERRE ◽  
ISABELLE COLOMBIER ◽  
CHANTAL ANDRAUD ◽  
...  
Keyword(s):  
Optical Tweezers ◽  
Polarized Light ◽  
Polarization Plane ◽  
Light Polarization ◽  
Good Prediction ◽  
Polarization Anisotropy ◽  
Two Photon ◽  
Flat Slabs ◽  
Linearly Polarized ◽  
Optical Torque

We study the rotational motion of objects trapped in a focused laser beam (optical tweezers). Micrometer-sized flat slabs are fabricated using two-photon photopolymerization. These objects, trapped by linearly-polarized light, tend to align parallel to the polarization plane. This alignment effect is attributed to the polarization anisotropy resulting from the object shape and we present a simple electromagnetic approach to estimate the resulting optical torque. Micro-rotors of different sizes are studied experimentally. We characterize the behavior of micro-objects when the light polarization is rotated at constant speed. Our theoretical approach gives a good prediction of how the size of micro-objects affects their rotation efficiency.

Design and Application of an In-Line Measurement System for Polarization Parameters

2013 ◽  
Vol 321-324 ◽  
pp. 447-452
Author(s):  
Zhang Bin Wen ◽  
Mi Zhou ◽  
Zhe Chen ◽  
Yun Han Luo
Keyword(s):  
Measurement System ◽  
High Speed ◽  
Low Cost ◽  
Extinction Ratio ◽  
Polarization State ◽  
Light Polarization ◽  
Polarization Measurement ◽  
Degree Of Polarization ◽  
Stokes Vector ◽  
Line System

An in-line all-fiber measurement system for polarization parameters is designed and fabricated in this paper. This system implements accurate control of polarization state, together with in-line, accurate, and high-speed measurement of Stokes vector. It can measure the light polarization parameters such as States of Polarization (SOP), Degree of Polarization (DOP), Light Polarization Extinction Ratio (LPER), and related losses of polarization. Besides, polarization monitoring and stabilizing can be achieved using this system. Because there is no discrete device concluded, the optical path of this system is completely constituted by optical fiber, which makes the entire system low-cost, with small size and low insertion loss. Keywords: All-fiber, polarization control, polarization measurement, in-line system, Stokes vector

Independent dominating sets in graphs of girth five

2020 ◽  
pp. 1-16
Author(s):  
Ararat Harutyunyan ◽  
Paul Horn ◽  
Jacques Verstraete
Keyword(s):  
Minimum Degree ◽  
Dominating Set ◽  
Regularity Conditions ◽  
Dominating Sets ◽  
Vertex Graph ◽  
First Results ◽  
Complete Bipartite Graphs ◽  
Image Position ◽  
Almost All ◽  
Independent Dominating Set

Abstract Let $\gamma(G)$ and $${\gamma _ \circ }(G)$$ denote the sizes of a smallest dominating set and smallest independent dominating set in a graph G, respectively. One of the first results in probabilistic combinatorics is that if G is an n-vertex graph of minimum degree at least d, then $$\begin{equation}\gamma(G) \leq \frac{n}{d}(\log d + 1).\end{equation}$$ In this paper the main result is that if G is any n-vertex d-regular graph of girth at least five, then $$\begin{equation}\gamma_(G) \leq \frac{n}{d}(\log d + c)\end{equation}$$ for some constant c independent of d. This result is sharp in the sense that as $d \rightarrow \infty$ , almost all d-regular n-vertex graphs G of girth at least five have $$\begin{equation}\gamma_(G) \sim \frac{n}{d}\log d.\end{equation}$$ Furthermore, if G is a disjoint union of ${n}/{(2d)}$ complete bipartite graphs $K_{d,d}$ , then ${\gamma_\circ}(G) = \frac{n}{2}$ . We also prove that there are n-vertex graphs G of minimum degree d and whose maximum degree grows not much faster than d log d such that ${\gamma_\circ}(G) \sim {n}/{2}$ as $d \rightarrow \infty$ . Therefore both the girth and regularity conditions are required for the main result.

scholarly journals 1.12. Structure of the inner galactic disk and the bulge - first results

1998 ◽  
Vol 184 ◽  
pp. 39-40
Author(s):  
S. Feltzing
Keyword(s):  
Observational Data ◽  
Globular Clusters ◽  
Spiral Galaxies ◽  
Galactic Disk ◽  
Galactic Bulge ◽  
Very Old ◽  
Difficult Question ◽  
First Results ◽  
Observational Status

Is there an age and/or a metallicity gradient in the Bulge? This is a notoriously difficult question because of the well known age-metallicity-distance degeneracy in colour magnitude diagrams (CMD) as well as the severe crowding and large reddening towards the Galactic Bulge. The current observational data on the bulge in our galaxy and bulges in other spiral galaxies point in disparate directions, that is evidence for both early (e.g. existence of very old halo and bulge globular clusters) and late formation (e.g. Sgr dSph and bar instabilities) can be found as well as the existence and non-existence of metallicity gradients (for a review of the observational status see Wyse, Gilmore & Franx 1997). We here present the CMDs for two fields, Baade's window and SGR-I, Fig.1c and d. Both these regions have low extinction. To determine the age and metallicity for these stars we compare the CMDs with CMDs of globular clusters, also observed with WFPC2, of known metallicity and age, Fig.1a and b. This method enables us to work entirely in the in-flight magnitude system of WFPC2 and there is no need for transformations to standard colours and magnitudes, something which is not straight forward for WFPC2 passbands.

Shooting for the moon: using tissue-mimetic hydrogels to gain new insight on cancer biology and screen therapeutics

2017 ◽  
Vol 7 (3) ◽  
pp. 427-441 ◽  
Author(s):  
Samantha E. Holt ◽  
E. Sally Ward ◽  
Raimund J. Ober ◽  
Daniel L. Alge
Keyword(s):  
Cancer Biology ◽  
The Moon ◽  
Image Position

Abstract

scholarly journals First Results from the Combination of the AAO/UKST and Marseille Hα Surveys

2001 ◽  
Vol 18 (1) ◽  
pp. 76-83 ◽  
Author(s):  
D. Russeil ◽  
Q. A. Parker
Keyword(s):  
Observational Data ◽  
Large Bubble ◽  
First Results

AbstractWe have combined the observational data of the AAO/UKST and Marseille Hα surveys to extract preliminary new results about ionised structures of our Galaxy. This includes the detection of a new large bubble located in the far part of the Carina arm.

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