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V405 Peg

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MUY's picture
V405 Peg

In Special Notice #314 it is noted that V405 Peg is 17.9V at minimum and 13V at maximum. Where does this come from? In the VSX V405 Peg is noted as a NL with small amplitude.



pukemaru's picture
V405 Peg

Eddy, the following comes from Astronomy & Physics Ms No aa22662 Dec 3, 2013 (arXiv:1313.0508v1) XMM-Newton observations of the low-luminosity cataclysmic variable V405 Pegasi
by A.D. Schwope1, V. Scipione1, I. Traulsen1, R. Schwarz1, T. Granzer1, A. M. Pires1, and J.R. Thorstensen2 
page 4 "The mean low-state spectrum obtained by Thorstensen et al. (2009) has synthetic magnitudes of gri = 17.9, 16.5, 15.4, re-spectively. "

In V405 Peg (RBS 1955): A Nearby, Low-Luminosity Cataclysmic Binary 1 John R. Thorstensen [arXiv:0904.3127v1 astro-ph.SR] 20 Apr 2009, it states on p6:
"High state photometry 2002/2003 In October/November 2002 and October 2003 the source was in a high state with an orbital averaged brightness of I = 13.95 and I = 14.02. At that time the light curves exhibited a near sinusoidal modulation with an amplitude of ∼ 0.25 mag, with strong flickering activity superimposed."
Maybe that's where the mag 13 comes from. 

Stephen [HSP]

Sebastian Otero
Sebastian Otero's picture
Not such a large amplitude

The high states reach 13.7 or so in the I band according to the papers quoted above but keep in mind that V-I= 1.8 or so for this object. So don't mix passbands.
AAVSO data over these years and a review of the papers you have mentioned gave a range of 15.1 - 17.1 in V with the star alternating between low and high states.
It has shown no outbursts and it is not actually an UG-type dwarf nova but a CV of an unknown subtype.


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