554 research outputs found
Digital Preservation and Web Access to the Konkoly Observatory Schmidt Telescope Plate Archive
ACM Computing Classification System (1998): J.2.The digital preservation of the Konkoly Observatory Schmidt
telescope plates, as well as the web access to the plate previews, aim for
the preservation of this scientific heritage and the re-use of the astronomical
photographic plates in time domain astronomy. The photographic plates
used as detectors and information storage at astronomical observations with
the Konkoly Schmidt telescope had been obtained in the period 1962–1996.
The work on the digital plate preservation and web access started in 2001
with creation of an electronic plate catalogue and the digitization of selected
representative plates as well as with interlinking of the publishing in Konkoly
Observatory Information Bulletin on Variable Stars (IBVS) with the Wide-Field Plate Database (WFPDB) developing in Sofia. We describe the process
of the digitization of the Konkoly Schmidt telescope plates.This work is supported by the bilateral project between the Bulgarian Academy of Sciences
and the Hungarian Academy of Sciences and partially by the grants BG NSF DO-02-273 and
BG NSF DO-02-275
Advanced Digital Competence of the Teacher
This chapter is devoted to the issues of changing the structure of the competence of teachers in the transformation of the school of the twenty-first century—the school of digital civilization. With this in mind, this chapter takes a fresh look at the advanced competencies of teachers of the near future in the context of these real school changes, the structure of which can be represented as the “triangle of digital competencies”: life, social, and professional. As shown by analytical studies and experimental experience of teacher training, the results of which are presented in this chapter, this triangle of competences will allow children to be included in the digital school environment and form their further activity in the smart education system in the profession throughout their lives. It is also important to note that new competencies have become the basis of a new profession in the school—a digital curator, which is also discussed in this chapter
Magnetic field structure in single late-type giants: Beta Ceti in 2010 - 2012
The data were obtained using two spectropolarimeters - Narval at the Bernard
Lyot Telescope, Pic du Midi, France, and ESPaDOnS at CFHT, Hawaii. Thirty-eight
circularly-polarized spectra have been collected in the period June 2010 -
January 2012. The Least Square Deconvolution method was applied for extracting
high signal-to-noise ratio line profiles, from which we measure the
surface-averaged longitudinal magnetic field Bl. Chromospheric activity
indicators CaII K, H_alpha, CaII IR (854.2 nm) and radial velocity were
simultaneously measured and their variability was analysed together with the
behavior of Bl. The Zeeman Doppler Imaging (ZDI) inversion technique was
employed for reconstruction of the large-scale magnetic field and two magnetic
maps of Beta Ceti are presented for two periods (June 2010 - December 2010 and
June 2011 - January 2012). Bl remains of positive polarity for the whole
observational period. The behavior of the line activity indicators is in good
agreement with the Bl variations. The two ZDI maps show a mainly axisymmetric
and poloidal magnetic topology and a simple surface magnetic field
configuration dominated by a dipole. Little evolution is observed between the
two maps, in spite of a 1 yr interval between both subsets. We also use
state-of-the-art stellar evolution models to constrain the evolutionary status
of Beta Ceti. We derive a mass of 3.5 M_sun and propose that this star is
already in the central-helium burning phase. Taking into account all our
results and the evolutionary status of the star, we suggest that dynamo action
alone may not be eficient enough to account for the high magnetic activity of
Beta Ceti. As an alternate option, we propose that it may be an Ap star
descendant presently undergoing central helium-burning and still exhibiting a
remnant of the Ap star magnetic field.Comment: 10 pages; 5 figures; 3 table
Super-Eddington accretion in the Q2237+0305 quasar?
The interband time lags between the flux variations of the Q2237+0305 quasar
have been determined from light curves in the Johnson-Cousins V, R, and I
spectral bands. The values of the time lags for filter pairs R-V, I-R, and I-V
are significantly higher than those predicted by the standard accretion disk
model by Shakura and Sunyaev. To explain the discrepancy, the idea of a
supercritical accretion regime in quasars considered in 1973 by Shakura and
Sunyaev is applied. This regime has been shown by them to cause an extended
scattering envelope around the accretion disk. The envelope efficiently
scatters and re-emits the radiation from the accretion disk and thus increases
the apparent disk size. We made use of analytical expressions for the envelope
radius and temperature derived by Shakura and Sunyaev in their analysis of
super-Eddington accretion and show that our results are consistent with the
existence of such an envelope. The corresponding parameters of the accretion
regime were calculated. They provide the radii of the envelope in the V, R, and
I spectral bands consistent with the inter-band time lags determined in our
work.Comment: 11 pages, 4 figure
Magnetic fields in single late-type giants in the Solar vicinity: How common is magnetic activity on the giant branches?
We present our first results on a new sample containing all single G,K and M
giants down to V = 4 mag in the Solar vicinity, suitable for
spectropolarimetric (Stokes V) observations with Narval at TBL, France. For
detection and measurement of the magnetic field (MF), the Least Squares
Deconvolution (LSD) method was applied (Donati et al. 1997) that in the present
case enables detection of large-scale MFs even weaker than the solar one (the
typical precision of our longitudinal MF measurements is 0.1-0.2 G). The
evolutionary status of the stars is determined on the basis of the evolutionary
models with rotation (Lagarde et al. 2012; Charbonnel et al., in prep.) and
fundamental parameters given by Massarotti et al. (1998). The stars appear to
be in the mass range 1-4 M_sun, situated at different evolutionary stages after
the Main Sequence (MS), up to the Asymptotic Giant Branch (AGB). The sample
contains 45 stars. Up to now, 29 stars are observed (that is about 64 % of the
sample), each observed at least twice. For 2 stars in the Hertzsprung gap, one
is definitely Zeeman detected. Only 5 G and K giants, situated mainly at the
base of the Red Giant Branch (RGB) and in the He-burning phase are detected.
Surprisingly, a lot of stars ascending towards the RGB tip and in early AGB
phase are detected (8 of 13 observed stars). For all Zeeman detected stars v
sin i is redetermined and appears in the interval 2-3 km/s, but few giants with
MF possess larger v sin i.Comment: 4 pages, 3 figures, Proceedings IAU Symposium No. 302, 201
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