scholarly journals Cross-Correlation of Large Scale Surveys: Radio-Loud Objects in the Rosat All Sky Survey

1998 ◽  
Vol 179 ◽  
pp. 447-448
Author(s):  
W. Brinkmann ◽  
W. Yuan ◽  
J. Siebert
Keyword(s):  
Large Scale ◽  
Cross Correlation ◽  
Broad Band ◽  
List Type ◽  
Type Number ◽  
Physical Conditions ◽  
Transfer Processes ◽  
Sky Survey ◽  
Wide Wavelength Range ◽  
Approaches To Study

There are basically two different approaches to study the physical conditions and the energy transfer processes operating in astronomical objects: – the detailed observations of a few prominent objects over a wide wavelength range.– the study of the broad band properties of suitably choosen samples

scholarly journals The Binary-Star Hypothesis for the Nucleus of NGC 1514

1968 ◽  
Vol 34 ◽  
pp. 324-328 ◽  
Author(s):  
L. Kohoutek
Keyword(s):  
Binary Star ◽  
Central Star ◽  
List Type ◽  
Type Number ◽  
High Brightness ◽  
Sky Survey ◽  
Type Spectrum ◽  
Ubv Photometry ◽  
The Difference ◽  
Central Stars

It is well known that the central star of the planetary nebula NGC 1514 (α50 = 4h06m.1, δ50 = +30°39'; lII= 165·5, bII = −15·3) differs from the other planetary nuclei by its high brightness (relative to the nebula) and late-type spectrum. The difference B∗ – Bn = 1m.9, and especially the A0-spectral type (Chopinet, 1963) are quite atypical for central stars. For these reasons we began a complex study of this object (Kohoutek, 1967; Kohoutek and Hekela, 1967) on the basis of the following sources of observational material: (1)Palomar Sky-Survey prints (Schmidt-camera, Palomar Observatory);(2)direct photographs in UBV system with the 2-m Schmidt-camera in Tautenburg (1962);(3)photoelectric UBV photometry with the 65-cm reflector at Ondřejov (1964–65),(4)(4) spectrograms of the central star using the 122-cm reflector in Asiago (1965), and relatively infrequent observational data from the older literature.

scholarly journals Using Narrow Emission Lines to Test Physical Models Unifying AGNs

1989 ◽  
Vol 134 ◽  
pp. 305-307 ◽  
Author(s):  
Steve Rawlings ◽  
Richard Saunders
Keyword(s):  
Large Scale ◽  
Line Strength ◽  
Physical Models ◽  
Emission Lines ◽  
Continuum Emission ◽  
List Type ◽  
Type Number ◽  
X Ray ◽  
Central Engine ◽  
Narrow Emission

We contend that quantitative measurements of nuclear narrow emission line strength can strongly constrain models that unify AGNs. The reasons for the importance of narrow-line luminosity LNLR are: a)The lines normally arise via photoionisation by the integrated UV/soft X-ray luminosity LPHOT of the central source. Thus LNLR is directly linked to a physical quantity intimately connected with the central engine but not observable from the ground. For constant covering factor we expect an approximate proportionality between LNLR and LPHOT; this has been confirmed observationally for AGNs by estimating LPHOT from either optical non-stellar luminosity or effective ionisation parameter.b)NLRs are far enough from the photoionising source to avoid the excessive obscuration that appears able to attenuate broad-line and continuum emission. Narrow-lines are radiated isotropically unlike, eg, the radio core which may be Doppler boosted. Their variability timescale of 103–4 years is intermediate between those of LPHOT and any large-scale radio emission.

scholarly journals Optical Spectra of Compact Objects

1972 ◽  
Vol 44 ◽  
pp. 109-126 ◽  
Author(s):  
E. M. Burbidge
Keyword(s):  
Radio Galaxies ◽  
Optical Spectra ◽  
Compact Objects ◽  
Energy Sources ◽  
List Type ◽  
Type Number ◽  
Physical Conditions ◽  
Class 1 ◽  
High Velocity Clouds ◽  
Probable Nature

On the basis of their optical spectra, compact objects are divided into 3 classes according to the probable nature of their energy sources, as follows: (1)Non-thermal: This class includes Seyfert nuclei, most N-type radio galaxies, and also very luminous Zwicky compact objects. The existence of high-velocity clouds, and a wide variety of densities and temperatures appear to be common characteristics of these objects. QSOs are considered to be related, with similar but more extreme properties.(2)Hot, massive stars: This class includes some small galaxies, parts of galaxies or appendages to galaxies, which are usually much less luminous than class (1) objects.(3)Stellar: Some compact galaxies having only absorption line spectra fall into this class.A variety of morphological forms exists amongst class (1) and (2) objects.Emission line spectra of QSOs are reviewed, and related to the physical conditions in the emitting regions.

scholarly journals Constraints on running of non-Gaussianity from large-scale structure probes

2019 ◽  
Vol 491 (1) ◽  
pp. L61-L65 ◽  
Author(s):  
Ji-Ping Dai ◽  
Jun-Qing Xia
Keyword(s):  
Spectral Index ◽  
Large Scale ◽  
Cross Correlation ◽  
Large Scale Structure ◽  
Scale Structure ◽  
Sloan Digital Sky Survey ◽  
Microwave Background ◽  
Sky Survey ◽  
Data Release ◽  
Clustering Data

ABSTRACT In this letter, we present constraints on the scale-dependent ‘local’-type primordial non-Gaussianity, which is described by non-Gaussianity’s spectral index nNG, from the NRAO VLA Sky Survey and the quasar catalogue of the Sloan Digital Sky Survey (SDSS) Data Release 6, together with the SDSS Data Release 12 photo-z sample. Here, we use the autocorrelation analyses of these three probes and their cross-correlation analyses with the cosmic microwave background (CMB) temperature map, and obtain the tight constraint on the spectral index: $n_{\rm NG}=0.2 ^{+0.7}_{-1.0}$ ($1\sigma$ C.L.), which shows the first competitive constraint on the running of non-Gaussianity from current large-scale structure clustering data. Furthermore, we also perform the forecast calculations and improve the limit of nNG using the future Euclid mission, and obtain the standard deviation at a 68 per cent confidence level: ΔnNG = 1.74 when considering the fiducial value fNL = 3, which provides the complementary constraining power to those from the CMB bispectrum information.

scholarly journals A re-evaluation of the yield from national surveys of mental health

2008 ◽  
Vol 5 (1) ◽  
pp. 18-20 ◽  
Author(s):  
Ronald C. Kessler ◽  
T. Bedirhan Üstün
Keyword(s):  
Mental Health ◽  
Large Scale ◽  
World Health ◽  
List Type ◽  
Type Number ◽  
National Surveys ◽  
World Mental Health Survey ◽  
High Prevalence ◽  
The World ◽  
Political Value

Having spent a considerable amount of time thinking about the uses of large-scale descriptive psychiatric epidemiological needs assessment surveys in our capacity as co-directors of the World Health Organization's World Mental Health Survey Initiative, we agree with many of the conclusions of Henderson and Andrews. Most importantly, we agree: ∘that among the most important benefits of these surveys have been their political value in documenting high prevalence and high disability∘that the time has come to expand the focus to study causes.

On the Association and Classification of Patients at Colney Hatch, and appropriation of the Recreation Room as a Dining Hall

1856 ◽  
Vol 3 (19) ◽  
pp. 114-116
Author(s):  
D. F. Tyerman
Keyword(s):  
Large Scale ◽  
Lunatic Asylum ◽  
List Type ◽  
Type Number ◽  
The Subject ◽  
Hot Weather

Encouraged by the success of the system, commenced in the year 1850, of associating at the dinner meal the male pauper patients of the Cornwall Lunatic Asylum, then under my superintendence, I ventured soon after my appointment at Colney Hatch, in September, 1852, to recommend here a far more extended association of the patients of both sexes in the hall hitherto used for occasional recreation, and which, from its dimensions and contiguity with the kitchen, appeared to offer especial advantages for carrying out such an experiment upon a large scale. After consultation with my colleagues upon the subject, I urged upon the Visiting Justices the following arguments in favour of the measure:— 1.The moral, social, and curative results likely to accrue.2.Relief to the patients from the usual monotony and routine of the establishment.3.Increased facilities afforded both to magistrates and officers for inspecting the patients.4.Improved ventilation in the wards, especially in hot weather.5.Removal of the knives, &c., from the store-rooms and sculleries of the wards.6.The more rapid conveyance of the provisions, whilst hot; and the better working of the establishment generally.

Plant Closures and the Productivity ‘Miracle’ in Manufacturing

1987 ◽  
Vol 121 ◽  
pp. 53-59 ◽  
Author(s):  
Nicholas Oulton
Keyword(s):  
Trade Unions ◽  
Large Scale ◽  
Slow Growth ◽  
Labour Productivity ◽  
Industrial Relations ◽  
List Type ◽  
Type Number ◽  
Productivity Level ◽  
Batting Average ◽  
Plant Closures

There has been a considerable improvement in labour productivity in UK manufacturing in the 1980s. Manufacturing output per person employed rose at an annual rate of only 0.7 per cent between 1973 and 1979 but at 4.1 per cent between 1979 and 1985. However, the cause or causes of this improvement have not been generally agreed. Muellbauer (1986) suggested five principal hypotheses to account for the improvement (see also Mendis and Muellbauer, 1984):(1)Technology, in particular the of the microelectronic revolution.(2)Improved industrial relations, due in part to the decline of unionism caused by the recession of the 1980s and in part to the change in the laws governing trade unions brought in by the first two Thatcher governments.(3)Capital scrapping—the period 1973–80 may have been one of large-scale unrecorded scrapping, since large parts of the capital stock became obsolete after the oil price rises; slow growth of capital per person would have led to slow growth in output per person but these trends may have been reversed after 1981.(4)Labour utilisation—this was low during the recession but the subsequent recovery produced a biased measure of the true productivity picture.(5)Plant closures—the recession led to the closure of low productivity plants, thus automatically raising the average productivity level of the survivors. The analogy with a batting average has sometimes been drawn—if the tail-enders are not allowed to bat, the average, though not of course the total, score is likely to be higher.

Solar Corona Investigation by the Coronal Line Photometer at Lomnický Peak

1994 ◽  
Vol 144 ◽  
pp. 431-434
Author(s):  
M. Minarovjech ◽  
M. Rybanský
Keyword(s):  
Solar Corona ◽  
Time Resolution ◽  
Active Regions ◽  
High Time ◽  
High Time Resolution ◽  
List Type ◽  
Type Number ◽  
Coronal Line ◽  
Global Cycle

AbstractThis paper deals with a possibility to use the ground-based method of observation in order to solve basic problems connected with the solar corona research. Namely:1.heating of the solar corona2.course of the global cycle in the corona3.rotation of the solar corona and development of active regions.There is stressed a possibility of high-time resolution of the coronal line photometer at Lomnický Peak coronal station, and use of the latter to obtain crucial observations.

The LDE-Type Flare Occurrence (1969-1993)

1994 ◽  
Vol 144 ◽  
pp. 279-282
Author(s):  
A. Antalová
Keyword(s):  
Time Series ◽  
Fourier Analysis ◽  
Sunspot Cycle ◽  
List Type ◽  
Type Number ◽  
Solar Cycles ◽  
Type Iv ◽  
Long Duration ◽  
Cycle Maximum ◽  
Flare Index

AbstractThe occurrence of LDE-type flares in the last three cycles has been investigated. The Fourier analysis spectrum was calculated for the time series of the LDE-type flare occurrence during the 20-th, the 21-st and the rising part of the 22-nd cycle. LDE-type flares (Long Duration Events in SXR) are associated with the interplanetary protons (SEP and STIP as well), energized coronal archs and radio type IV emission. Generally, in all the cycles considered, LDE-type flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the sunspot cycle maximum). The following significant periodicities were found:• in the 20-th cycle: 1.4, 2.1, 2.9, 4.0, 10.7 and 54.2 of month,• in the 21-st cycle: 1.2, 1.6, 2.8, 4.9, 7.8 and 44.5 of month,• in the 22-nd cycle, till March 1992: 1.4, 1.8, 2.4, 7.2, 8.7, 11.8 and 29.1 of month,• in all interval (1969-1992):a)the longer periodicities: 232.1, 121.1 (the dominant at 10.1 of year), 80.7, 61.9 and 25.6 of month,b)the shorter periodicities: 4.7, 5.0, 6.8, 7.9, 9.1, 15.8 and 20.4 of month.Fourier analysis of the LDE-type flare index (FI) yields significant peaks at 2.3 - 2.9 months and 4.2 - 4.9 months. These short periodicities correspond remarkably in the all three last solar cycles. The larger periodicities are different in respective cycles.

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