53 research outputs found
Emission Line Flickering from the Secondary Star in Cataclysmic Variables? A study of V3885 Sagitarii
Spectrophotometric observations of H-alpha and He I 6678 emission lines of
the nova-like Cataclysmic Variable V3885 Sgr are presented and analyzed. The
binary orbital period was determined as P = 0.20716071(22) days. Doppler
Tomography was performed with both H-alpha and He I lines. Disc radial
emissivity profiles were also computed. The tomography mapping of flickering
sources was performed using the H-alpha line, from which we concluded that the
flickering is not uniformly distributed on the disc. The observed tomogram of
the flickering was compared with simulations, suggesting that the most intense
flickering source in the H-alpha is not located in the accretion disc. It is
proposed that the main line flickering source may be associated with the
illuminated secondary star.Comment: 19 pages, 10 figures, 1 table. Accepted to be published on AJ. to
donwload high resolution figures:
http://www.astro.iag.usp.br/~fabiola/V3885_hires.pd
A tomographic study of the classical nova RR Pic
We present the results of spectrophotometric observations of the old nova RR
Pic performed in two spectral ranges, one centered in the Ha line and other
covering Hb and Hg spectral lines. From the Hb radial velocity study we found a
primary radial semi-amplitude of K1 = 37(1) km/s and a systemic velocity of g =
1.8(2) km/s. With this new values a mass diagram is constructed, constraining
the possible mass intervals for the system. The possible orbital inclination
range was restricted using the fact that RR Pic presents shallow eclipses. A
secondary mass range below the limit of a main sequence star filling its Roche
lobe indicate an evolved companion. We also calculated the Ha, Hb, Hg, HeI 6678
and HeII 4686 Doppler tomograms. The most conspicuous differences are found
between the HeI and HeII tomograms, the former has a ring shape, while the
second is filled at low velocities, suggesting that the low velocity emission
is not coming from the accretion disk. Radial emissivity profiles for these
lines were also derived.Comment: 8 pages, 8 figures, accepted to appear in PAS
Relações entre caracterĂsticas fĂsicas e quĂmicas de frutos de maracujazeiro-doce cultivado em Viçosa-MG
Stereological study of the elastic fiber and smooth muscle cell system in the bovine and buffalo penis
Follow-up on pediatric patients with bronchiolitis obliterans treated with corticosteroid pulse therapy
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