2003 MC7

Scritto in Pubblicazioni

Available from the Minor Planet Center.
Available from the Minor Planet Center.

Transient Heavy Element Absorption Systems in Novae: Episodic Mass Ejection from the Secondary Star

Scritto in Pubblicazioni

A high-resolution spectroscopic survey of post-outburst novae reveals
short-lived heavy element absorption systems in a majority of novae near
maximum light, having expansion velocities of 400-1000 km s<SUP>-1</SUP>
and velocity dispersions between 35 and 350 km s<SUP>-1</SUP>. A
majority of systems are accelerated outward, and they all progressively
weaken and disappear over timescales of weeks. A few of the systems
having narrow, deeper absorption reveal a rich spectrum of singly
ionized Sc, Ti, V, Cr, Fe, Sr, Y, Zr, and Ba lines. Analysis of the
richest such…

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COMET C/20

Scritto in Pubblicazioni

Available from the Minor Planet Center.
Available from the Minor Planet Center.

A Comparative Test of CCD Reduction Procedures

Scritto in Pubblicazioni

Three data reduction methods, applicable to time-resolved CCD photometry
of open clusters, are described. A sample set of images is reduced
independently by three people, using various approaches, and the results
are compared. The test reveals systematic differences in the FWHM and
magnitudes produced by the different software. The reduction package
MOMF and pure aperture photometry are found to be equivalent in
precision, but the results obtained with these methods should not be
merged when high precision is required.