* Astronomy

Blobrana · L

RE: SY Cancri

Blobrana · L

The dwarf nova SY Cancri is in outburst.

Date: 14th February, 2012
Magnitude range: 10.6 - 14.0
Period: ?
Satellite period: 0.3823753 days
Type: UGZ

Position(2000): RA=09 01 03.32 | Dec=+17° 53' 56.0"

Blobrana · L

The dwarf nova SY Cancri is in outburst.

Date: 21st January, 2012
Magnitude range: 10.6 - 14.0
Period: ?
Satellite period: 0.3823753 days
Type: UGZ

Position(2000): RA=09 01 03.32 | Dec=+17° 53' 56.0"

Blobrana · L

The Z Cam type dwarf nova SY Cancri is in outburst.

Date: 30th December, 2011
Magnitude range: 10.6 - 14.0
Period: ?
Satellite period: 0.3823753 days
Type: UGZ

Position(2000): RA=09 01 03.32 | Dec=+17° 53' 56.0"

Blobrana · L

The Z Cam type dwarf nova SY Cancri is in outburst.

Date: 6th December, 2011
Magnitude range: 10.6 - 14.0
Period: ?
Satellite period: 0.3823753 days
Type: UGZ

Position(2000): RA=09 01 03.32 | Dec=+17° 53' 56.0"

Blobrana · L

The Z Cam type dwarf nova SY Cancri is in outburst.

Date: 3rd June, 2011
Magnitude range: 10.6 - 14.0
Period: ?
Satellite period: 0.3823753 days
Type: UGZ

Position(2000): RA=09 01 03.32 | Dec=+17°53'56.0"

Blobrana · L

The Z Cam type dwarf nova SY Cancri is in outburst.

Date: 8th March 2011
Magnitude range: 10.6 - 14.0
Period: ?
Satellite period: 0.3823753 days
Type: UGZ

Position(2000): RA=09 01 03.32, Dec=+17°53'56.0"

Blobrana · L

Title: SY Cancri, a case for unstable mass transfer?
Authors: J. Casares, I. G. Martinez-Pais, P. Rodriguez-Gil

Intermediate resolution (0.5-1 Angs) optical spectroscopy of the cataclysmic variable SY Cnc reveals the spectrum of the donor star. Our data enable us to resolve the orbital motion of the donor and provide a new orbital solution, binary mass ratio and spectral classification. We find that the donor star has spectral type G8±2 V and orbits the white dwarf with P=0.3823753 ± 0.0000003 day, K2=88.0 ±2.9 km/s and V sin i=75.5 ± 6.5 km/s. Our values are significantly different from previous works and lead to q=M2/M1=1.18 ± 0.14. This is one of the highest mass ratios known in a CV and is very robust because it is based on resolving the rotational broadening over a large number of metallic absorption lines. The donor could be a slightly evolved main-sequence or descendant from a massive star which underwent an episode of thermal-timescale mass transfer.

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