Schwache blaue Objekte in der Nähe des galaktischen Nordpols (Umgebung von M 3)

Der hohe Prozentsatz von Variablen unter den Blauen Objekten, der in friiheren Untersuchungen gefunden worden war, wird auf 170 Tautenburger Schmidt-Platten in zwei Testfeldern bei M 31 iiberpriift. Der hohe Anteil konnte nicht bestatigt werden. Scheinbare Amplituden konnen durch die groI3en wahrscheinlichen Fehler bei der photographischen Photometrie (insbesondere an der Grenzhelligkeit der Platten) erkliirt werden, sowie durch schlechte Eignung von besonders scharfen Schmidt-Platten fur eine photographische Integralphotometrie. Von 37 untersuchten Blauen Objekten erwiesen sich nur z (VAN DEN BBRCH 5 und 12) als eindeutig variabel. Die endgiiltige Priifung von Blauen Objekten, die der Veranderlichkeit verdachtigt werden, kann jedoch nur durch photoelektrische Photometrie geschehen.The reality of the high percentage of variability among Blue Objects which was found in previous investigations was examined on 170 Tautenburg Schmidt plates of two test fields near M 31. The high percentage could not be confirmed. Spurious amplitudes can be explained by the large probable errors of the photometry (especially near the plate limit) and by bad suitability of good-looking plates. Out of 37 Blue Objects examined, onIy two (VAN DEN BERGH 5 and 12) are distinctly variable, but the final examination of Blueobjects which are suspected of variability can only be clone by photoelectric photometry.

Section: Methods and Resultsmentioning

confidence: 99%

Section: Methods and Resultsmentioning

confidence: 99%

See 1 more Smart Citation

On the variability of the “blue objects”

Richter¹,

Richter²,

Wenzel³

1971

“…Additional estimates of lower limits of b can be derived from some independent sources. Firstly, the slope of the N ( m ) curves of unclassified "blue objects", which have been repeatedly determined (SANDAGE and LUYTEN 1969, BRACCESI and FORMIGGINI 1969, BRONKALLA 1971 can be used, because according to the arguments above these curves contain mainly objects within constant limits of z (s(z) independent on mj ; the slope will be lowered, however, by a slight excess of nearby objects of high luminosity a t bright magnitudes and, of course, by galactic stars which are preponderant at these same bright magnitudes. We derive from the cited papers b > 0.65 ... 0.75.…”

Section: The Value Of the Exponentmentioning

confidence: 99%

Comments on the HUBBLE Diagram, the Luminosity Function and the Space Density Evolution of Radio Quiet Quasars

Notni

1979

The consequences of a pure power law luminosity function on the distribution of objects in the HUBBLE diagram are described. As long as such a law acts, magnitudes do not contain any information on distances. A high value of the coefficient of the luminosity function of radio quiet quasars, b = 0.95 5 0.05 in the expression lg p(M) -6 . M , is shown to be plausible. This implies a high density evolution, e -(I + z)k, with k near g-10. Findings from modern samples, searched on low-dispersion spectral plates point to an even stronger evolution at z < z .5 ; the discrepancy may be removed if L,/Hb > 3 (about 30) for these radio-quiet QSOs.

Blaue Objekte in der Umgebung von M 31 I. Entdeckungswahrscheinlichkeit neu aufgefundener Blauer Objekte

Richter

Meinunger

1972

This paper presents the first part of an extensive investigation of blue objects in the 5C3 area (centre near oh40m +3g0) in order to find out the probability of discovery, the total of quasi-stellar objects, the abundance in correlation with the apparent brightness, as well as the analysis of a relation to radio sources of small diameter in the 5C3 catalogue [8].The present first part contains two further plate comparisons of a section of 2.5 square degrees -already