Search

Start Over Subject observations

11. Data acquisition at the 700mm CCD camera of the Ondřejov telescope coudé spectrograph

Creator:
Šlechta, Miroslav and Škoda, Petr
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
astrophysical data, observations, spectrorgaphs, and CCD
Language:
Czech
Description:
We present a short tutorial on driving the 2-meter telescope coudé spectrograph and on acquisition of scientific data. We hope that visitors collaborating with stellar department will appreciate this tutorial as an useful cookbook. Although the user interface driving the spectrogtaph and CCD controller is quite comfortable, it is not possible to find or understand all keywords and commands intuitively. Therefore we present this manual containing all necessary commands with descriptions and examples.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

13. Distribution of interplanetary dust

Creator:
Giese, R. H. and Kneißel , B.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations and interplanetary dust
Language:
Czech
Description:
Simple 3D distributions of the interplanetary dust cloud deríved from observations in the visible and distributions suggested by IR investigators are compared. Predictions of visual brightness based on IR models are falrly compatible with observations for large (ε<70°) elongations but not close to the Sun. Some reasons for this behaviour and first steps towards more realistic models are díscussed.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

14. Distribution of OB associations and open star clusters

Creator:
Lyngå, Gösta
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations, open clusters and associations, and galactic structure
Language:
Czech
Description:
Observations of photometric and spectroscopic data for open clusters and associations have been intensive during the last few years. Incentives are many: - each cluster is an object for which the state of evolution and other characteristics can be studied much better than for individual stars - the systems of open clusters and associations in our own and other galaxies give information about the recent evolution of the galaxies themselves - the clusters and associations are sensors of the conditions in interstellar space Collections of observed data have been made by Alter, Ruprecht, Balazs, Vanysek and White in the comprehehsive Prague-Budapest card catalogues. My own efforts in this direction have resulted in computer readable catalogue of open cluster data, of which the 5th edition appeared recently. In collaboration with K. Janes and C. Tilley of Boston University, I have now entered weight classes. The purpose of these is to monitor the reliability of conclusions based on cluster data. It seems that physical systems of 10-1000 stars can be divided into three categories; - associations and unbound open clusters - bound open clusters in the disk - old open clusters Properties such as age, linear diameter and abundances are discussed for these categories on the basis of the data contained in the Lund catalogue. The galactic distribution of young clusters and associations shows the existence of complexes inside the thin disk. The system of old open clusters seems to back up the concept of a thick disk.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

15. Dynamical constants for our galaxy

Creator:
Slobodan
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations, galaxy, and dynamical constants
Language:
Czech
Description:
According to the present author´s results a following system of the galactic dynamical constants is proposed: local escape velocity, u = (520+30) km s^-1, local circular velocity, u = (230+30) km s^-1, local angular velocity of rotation, ω = (25+5) km s^-1 kpc^-1, local circular frequency of planar oscillations, κp = (40+10) km s^-1, local circlar frequency of vertical oscillations, κz = (70120) km^-1 kpc^-1. The value of (9+1), kpc is assumed fpar the galactocentric distance of the Sun. The latter three values yield (0.09±0.03) pc^-3 for the local matter density, a value very close to the density obtained by use of statistical methods. On the basis of the proposed value it is concluded that the dark matter should to present in the form of a large, rerefied, massive, spherical corona.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

16. Early stages of star formation

Creator:
Chini, Rolf
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations, star formation, and interstellar material
Language:
Czech
Description:
Different aspects of star formatlon are discussed on the basis of new submm observations. In NGC2024 slx cold (T-16K) and dense (nH“lE8-lE9cm^-3) so far unknown condensations are found and interpreted as isothermal protostars. The density and temperature structure around massive early type stars which are deeply embedded in dense regions is discussed by means of thermai emission from dust. A star formation efficiency of 8% is derived from 90 compact HII regions. A comparison with the star formation in normal spiral galaxles and active Markarlan objects leads to a new deflnltion of actlvity. The L/M ratlo of active sytems is by a factor of 20 higher than the corresponding value in normal splrals and galactic HII regions.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

18. Evolutionary aspects of the solar active regions

Creator:
Stepanyan, N. N. and Antalová, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
astrophysics, solar active regions, and observations
Language:
Czech
Description:
Simultaneous observations of the H-alpha and Ca II K floccular lines show that during the first three days of the newly formed flocculi the temperature grows gradually, while the density is practically constant. During the following days an increase in density is observed, The phase of increasing density does not occur in the case of faint flocculi. The K-line analysis of the six newly - formed sunspots indicates that the average cooling upward velocity equals 15 ms”' . An increase in sunspot induction was observed at the time of the flares (46 spots, Fig. 5).
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

19. Fast variability in low-mass X-ray binaries

Creator:
van Paradijs, Jan
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations, quasi-periodic oscillations, and low-mass X-ray binaries
Language:
Czech
Description:
Quasi-periodic oscillations /QPO/, with frequencies in the range between about 1 Hz and 10^2 Hz have been detected in the X-ray flux of 10 low-mass X-ray binaries. A brief overview will be given of the main characteristics of these QPO, and the associated red noise, with emphasis on the following topics: - The relation between QPO and the spectraL properties of the LMXB; - The time shift between QPO as observed in different X-ray photon energy bands, and the possible role of comptonization in the formation of X-ray spectra of low-mass X-ray binaries.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

20. Height variations of prominence plasma parameters

Creator:
Kotrč, P., Heinzel, P., Vial, J.-C., and Rompolt, B.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations and prominence plasma parameters
Language:
Czech
Description:
High-resolution prominence spectra in Hα and Hβ lines have been obtained at Sacramento Peak Observatory. Here we present first results of their analysis and compare out data with those reported by other authors. A preliminary comparison with theoretical intensities is also discussed.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public