scholarly journals The Center for Astrophysics Redshift Survey

1988 ◽  
Vol 130 ◽  
pp. 105-112
Author(s):  
J. Huchra ◽  
M. Geller ◽  
V. de Lapparent ◽  
R. Burg
Keyword(s):  
Emission Lines ◽  
Clusters Of Galaxies ◽  
Local Universe ◽  
Abell Clusters ◽  
The Poor ◽  
Redshift Survey ◽  
The Mean

The first CfA Survey is now over 90% spectroscopically complete. Over 60% of all galaxies exhibit detectable emission lines. We have also completed five slices of the Center for Astrophysics (CfA) redshift survey extension. The geometry of the structures in the first slice persists; galaxies are distributed on thin surfaces of “bubble-like” structures. Empty regions or “voids” are common, come in a variety of sizes ranging up to 5,000 km s−1, and are underdense by factors of up to 5 w.r.t. the mean. These voids fill ∼ 80% of the volume of the local universe. Clusters of galaxies lie at the interstices of bubbles; some of the poor Abell clusters do not exist as “fingers” in redshift space. The surfaces are very thin with an average FWHM less than 500 km s−1 in redshift space (σ ∼ 200 to 250 km s−1).

scholarly journals Catalogue of Clusters that are Members of Superclusters

1983 ◽  
Vol 104 ◽  
pp. 185-186
Author(s):  
M. Kalinkov ◽  
K. Stavrev ◽  
I. Kuneva
Keyword(s):  
Standard Deviation ◽  
Correlation Coefficient ◽  
The Other ◽  
Clusters Of Galaxies ◽  
Number Of Clusters ◽  
Abell Clusters ◽  
The Mean ◽  
Abell Cluster ◽  
Image Position

An attempt is made to establish the membership of Abell clusters in superclusters of galaxies. The relation is used to calibrate the distances to the clusters of galaxies with two redshift estimates. One is m10, the magnitude of the ten-ranked galaxy, and the other is the “mean population,” P, defined by: where p = 40, 65, 105 … galaxies for richness groups 0, 1, 2 …, and r is the apparent radius in degrees given by: The first iteration for redshift, z1, is obtained from m10 alone: The standard deviation for Eq. (1) is 0.105, the number of clusters with known velocities is 342 and the correlation coefficient between observed and fitted values is 0.921. With zi from Eq. (1), we define Cartesian galactic coordinates Xi = Rih−1 cosBi cosLi, Yi = Rih−1 cosBi sinLi, Zi = Rih−1 sinBi for each Abell cluster, i = 1, …, 2712, where Ri is the distance to the cluster (Mpc), and Ho = 100 h km s−1 Mpc−1.

scholarly journals The Perseus Supercluster

1983 ◽  
Vol 104 ◽  
pp. 273-280
Author(s):  
Riccardo Giovanelli
Keyword(s):  
Surface Density ◽  
Large Scale ◽  
Volume Density ◽  
Clusters Of Galaxies ◽  
Large Area ◽  
Local Universe ◽  
Density Enhancement ◽  
Redshift Survey ◽  
The One ◽  
The Universe

In analyzing the distribution of galaxies of a sample projected on the plane of the sky, the magnitude of a surface density enhancement produced by a clumpy structure depends on the size and magnitude of the volume density enhancement, and the depth of the sample. If the sample is too deep, or the line of sight size or volume overdensity of the clump too small, the surface enhancement may be too shallow to discern against the fore- and background objects. The Catalogue of Galaxies and Clusters of Galaxies (CGCG: Zwicky et al. 1960–68) provides a representative sample of the local universe (cz ≤ 15000 km s−1) and, in hindsight, possibly the one available that best enhances the inhomogeneities that appear to characterize the large scale structure of the universe. Using maps of the surface density distribution of galaxies from the CGCG, of which figure 1 is an example, Martha Haynes, Guido Chincarini and I have selected a number of filamentary structures discernable and undertaken a 21 cm redshift survey of large regions enclosing them, with the telescopes of 305 m at Arecibo and 92 m at NRAO-Green Bank. Here I shall discuss our current results from a large area extending from Pegasus to Ursa Major, which engulfs the well known Perseus supercluster (Einasto et al. 1980; Gregory et al. 1981).

scholarly journals Length-weight relationships and condition factor of Hyperopisus bebe (Lacepede, 1803) (Actinopterygii: Osteoglossiformes) in River Galma, Zaria, Kaduna State, Nigeria

2017 ◽  
Vol 4 (8) ◽  
pp. 301-305
Author(s):  
Matouke M. Moise
Keyword(s):  
Water Quality ◽  
Water Body ◽  
Growth Pattern ◽  
Condition Factor ◽  
Allometric Growth ◽  
Male And Female ◽  
B Values ◽  
The Poor ◽  
Poor Water Quality ◽  
The Mean

The investigation of length-weight relationship and condition factor are very relevant indices to ascertain the health of fish in the water body. Length-weigh relationship and condition factor of Hyperopisus bebe (Lacepede, 1803) (Actinopterygii: Osteoglossiformes: Mormyridae) in River Galma, Zaria, Kaduna State, Nigeria, were assessed. The mean length and mean weigh in male and female were 26.703 cm +/- 0.51 cm and 25.32 cm +/- 0.898 cm; 158.2 g +/- 10.1 g and 95.91 g +/- 9.26 g, respectively. The exponent or growth pattern 'b' values for male and female were 2.009 and 2.176. The condition factor for male and female were 0.59 and 0.83, respectively. The negative allometric growth pattern and poor condition factor might be due to the poor water quality in the fish ecosystem and should be regarded with concern.

scholarly journals Monitoring inner London mental illness services

1995 ◽  
Vol 19 (5) ◽  
pp. 276-280 ◽  
Author(s):  
◽  
Bernard Audini ◽  
Michael Crowe ◽  
Joan Feldman ◽  
Anna Higgitt ◽  
...  
Keyword(s):  
Mental Illness ◽  
Psychiatric Care ◽  
Bed Occupancy ◽  
Local Data ◽  
Catchment Population ◽  
The Poor ◽  
Number Of Patients ◽  
The Mean ◽  
Acute Psychiatric Care ◽  
The Impact

Our objective was to establish a mechanism for monitoring indicators of the state of health of inner London's mental illness services. Data were collected for a census week around 15 June 1994. Local data collection was coordinated by consultant pyschiatrists working in inner London services. Twelve services participated with a combined catchment population of 2.6 m. They included ten London services which were among the 17 most socially deprived areas of England. Main indicators were admission bed occupancy levels (including an estimate of the total requirement), proportion of patients detained under the Mental Health Act, number of assaults committed by inpatients, number of emergency assessments and CPN caseloads. The mean true bed occupancy (which reflects the number of patients who were receiving, or required, in-patient care on census day) was 130%. To meet all need for acute psychiatric care, including for patients who should have been admitted and those discharged prematurely because beds were full, a further 426 beds would have been required. Fifty per cent of patients were legally detained. Physical assaults were virtually a daily occurrence on the admission units. Average community pyschiatric nurse caseloads were 37, suggesting that the majority were not working intensively with limited caseloads of patients with severe mental illness. These indicators, although imperfect, will allow for some measurement of the impact of local and central initiatives on the poor state of London's mental illness services.

scholarly journals Recent studies of the spectrum of V1016 Cygni

1982 ◽  
Vol 70 ◽  
pp. 161-164
Author(s):  
G. Muratorio ◽  
M. Friedjung
Keyword(s):  
Radial Velocity ◽  
Ionization Potential ◽  
Radial Velocities ◽  
Emission Lines ◽  
Computer Programme ◽  
Half Maximum ◽  
The Mean ◽  
Effective Ionization

Two coudé spectra of V1016 Cyg taken on June 24 and 27, 1979 were reduced, using a computer programme developed in Marseille. Radial velocities and full widths at half maximum were measured for the emission lines, and are summarized in the following table were VR is the mean radial velocity in km s-1, DV the velocity corresponding to the mean FWHM and Xi the effective ionization potential for the ion.

scholarly journals The reproductive success of black rhinoceroses in the Hluhluwe–iMfolozi Park, KwaZulu-Natal, South Africa

Koedoe ◽  
2017 ◽  
Vol 59 (1) ◽  
Author(s):  
Zoliswa N. Nhleko ◽  
Dan M. Parker ◽  
Dave J. Druce
Keyword(s):  
South Africa ◽  
Carrying Capacity ◽  
Black Rhinoceros ◽  
Ecological Carrying Capacity ◽  
Diceros Bicornis ◽  
The Poor ◽  
Kwazulu Natal ◽  
Southern Central ◽  
Target Period ◽  
The Mean

Black rhinoceroses (Diceros bicornis) are endangered and the southern-central sub-species (Diceros bicornis minor) is considered critically endangered. We assessed the reproductive lifehistories of black rhinoceroses in Hluhluwe–iMfolozi Park (HiP), KwaZulu-Natal, South Africa, to determine whether this historically important donor sub-population was meeting regional reproductive targets. Detailed life-history information for known individuals (n = 79–120) was used to investigate reproductive parameters between 1998 and 2013. Mean age at sexual maturity was 12 years, which exceeded a target period of 7 years and 5 months. The mean inter-calving interval was 3 years and 8 months – 8 months longer than the recommended 3 years. The poor population performance of the HiP black rhinoceroses could be a result of poor habitat quality, poor animal condition, females losing their first calves, predation of calves or a negative social effect of annual live-harvesting of the population. However, we believe that the estimated ecological carrying capacity of black rhinoceroses at HiP (a figure used to ascertain whether the population can be harvested at all) may be incorrect, leading to the poor reproductive performance. We recommend that the accuracy of the ecological carrying capacity estimate be assessed as a matter of urgency and that a moratorium be placed on the live-harvesting of individuals until the estimate has been refined.Conservation implications: Our results provide key data which can be used to refine black rhinoceros breeding targets in South Africa and the region more broadly

scholarly journals Assessing the photometric redshift precision of the S-PLUS survey: the Stripe-82 as a test-case

2020 ◽  
Vol 499 (3) ◽  
pp. 3884-3908 ◽  
Author(s):  
A Molino ◽  
M V Costa-Duarte ◽  
L Sampedro ◽  
F R Herpich ◽  
L Sodré ◽  
...  
Keyword(s):  
Simultaneous Detection ◽  
Control Sample ◽  
Emission Lines ◽  
Test Case ◽  
Local Universe ◽  
Photometric Redshift ◽  
Luminosity Functions ◽  
Passband Filter ◽  
Statistical Studies ◽  
Narrow Bands

ABSTRACT In this paper we present a thorough discussion about the photometric redshift (photo-z) performance of the Southern Photometric Local Universe Survey (S-PLUS). This survey combines a seven narrow +5 broad passband filter system, with a typical photometric-depth of r ∼ 21 AB. For this exercise, we utilize the Data Release 1 (DR1), corresponding to 336 deg2 from the Stripe-82 region. We rely on the BPZ2 code to compute our estimates, using a new library of SED models, which includes additional templates for quiescent galaxies. When compared to a spectroscopic redshift control sample of ∼100 k galaxies, we find a precision of σz <0.8 per cent, <2.0 per cent, or <3.0 per cent for galaxies with magnitudes r < 17, <19, and <21, respectively. A precision of 0.6 per cent is attained for galaxies with the highest Odds values. These estimates have a negligible bias and a fraction of catastrophic outliers inferior to 1 per cent. We identify a redshift window (i.e. 0.26 < z < 0.32) where our estimates double their precision, due to the simultaneous detection of two emission lines in two distinct narrow bands; representing a window opportunity to conduct statistical studies such as luminosity functions. We forecast a total of ∼2 M, ∼16 M and ∼32 M galaxies in the S-PLUS survey with a photo-z precision of σz <1.0 per cent, <2.0 per cent, and <2.5 per cent after observing 8000 deg2. We also derive redshift probability density functions, proving their reliability encoding redshift uncertainties and their potential recovering the n(z) of galaxies at z < 0.4, with an unprecedented precision for a photometric survey in the Southern hemisphere.

scholarly journals IUE Spectra of The by Dra/Flare Star AU Mic

1983 ◽  
Vol 71 ◽  
pp. 249-250
Author(s):  
C.J. Butler ◽  
A.D. Andrews ◽  
J.G. Doyle ◽  
P.B. Byrne ◽  
J.L. Linsky ◽  
...  
Keyword(s):  
Light Curve ◽  
Emission Line ◽  
Flare Star ◽  
Emission Lines ◽  
Spectral Variation ◽  
Strong Emission ◽  
Line Intensities ◽  
The Mean ◽  
Phase Interval

A coordinated series of ground-based optical and IUE observations of BY Dra variables was undertaken to follow the spectral variation of these stars over one cycle. In the first series 20 LWR and 19 SWP trailed spectra were taken of AU Mic over a three day period 4-6 August 1980 .In Figure 1 we show the mean integrated fluxes for the strong emission lines in the SWP spectra of AU Mic over the observed phase interval of 0.14 to 0.8 together with an approximate V light curve determined by the FES on IUE. From comparison of the emission line intensities and FES magnitudes in Figure 1 several points emerge.

scholarly journals Highly-luminous Cool Core Clusters of Galaxies: Mechanically-driven or Radiatively-driven AGN?

2010 ◽  
Vol 6 (S277) ◽  
pp. 329-332
Author(s):  
Julie Hlavacek-Larrondo ◽  
Andy Fabian
Keyword(s):  
Surrounding Medium ◽  
Clusters Of Galaxies ◽  
X Ray ◽  
Energy Feedback ◽  
Bolometric Luminosity ◽  
Strong Energy ◽  
The Mean ◽  
Intracluster Gas ◽  
Jet Power ◽  
Very High

AbstractCool core clusters of galaxies require strong feedback from their central AGN to offset cooling. We present a study of strong cool core, highly-luminous (most with Lx ≥ 1045 erg s−1), clusters of galaxies in which the mean central AGN jet power must be very high yet no central point X-ray source is detected. Using the unique spatial resolution of Chandra, a sample of 13 clusters is analysed, including A1835, A2204, and one of the most massive cool core clusters, RXCJ1504.1-0248. All of the central galaxies host a radio source, indicating an active nucleus, and no obvious X-ray point source. For all clusters in the sample, the nucleus has an X-ray bolometric luminosity below 2 per cent of that of the entire cluster. We investigate how these clusters can have such strong X-ray luminosities, short radiative cooling-times of the inner intracluster gas requiring strong energy feedback to counterbalance that cooling, and yet have such radiatively-inefficient cores with, on average, Lkin/Lnuc exceeding 200. Explanations of this puzzle carry significant implications for the origin and operation of jets, as well as on establishing the importance of kinetic feedback for the evolution of galaxies and their surrounding medium.

Redshifts of radio galaxies in Abell clusters of galaxies

1988 ◽  
Vol 95 ◽  
pp. 1 ◽  
Author(s):  
Frazer N. Owen ◽  
Richard A. White ◽  
Harley A., Jr. Thronson
Keyword(s):  
Radio Galaxies ◽  
Clusters Of Galaxies ◽  
Abell Clusters
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