# Photometric study of the very short period shallow contact binary DD Comae Berenices

## DSpace/Manakin Repository

 aaK citaci nebo jako odkaz na tento záznam použijte identifikátor: http://hdl.handle.net/10084/83561
﻿
 dc.contributor.author Zhu, L. dc.contributor.author Qian, Sheng-Bang dc.contributor.author Mikulášek, Zdeněk dc.contributor.author Zejda, Miloslav dc.contributor.author Zvěřina, P. dc.contributor.author Diethelm, R. dc.date.accessioned 2011-01-12T08:24:21Z dc.date.available 2011-01-12T08:24:21Z dc.date.issued 2010 dc.identifier.citation The astronomical journal. 2010, vol. 140, no. 1, p. 215-223. en dc.identifier.issn 0004-6256 dc.identifier.issn 1538-3881 dc.identifier.uri http://hdl.handle.net/10084/83561 dc.description.abstract The first photometric solutions of the very short period (VSP) close binary DD Comae Berenices (P = 0fd26920811) based on our new complete (IR)C light curves are derived by the 2003 version Wilson-Van Hamme code. They show that the system belongs to shallow contact W-type W UMa systems with a degree of overcontact of 8.7%. The observed light curve distortions are explained by employing the spots model due to the late-type nature of both components. We have collected all available photometric data about the system with emphasis on the individual observational data, which we treated simultaneously using our own method based on the usage of computed model light curves as templates. We recalculated published times of light minimum and added new ones of our own to construct an O – C diagram that spans over 70 years. Using a least squares method orthogonal quadratic model function, we found that the orbital period of DD Com is continuously increasing with $\dot{P}=0.00401(22)$ s yr–1. The period increase may be caused by the mass transfer from the less-massive component to the more-massive one. With the period increase, the binary is evolving from the present shallow contact phase to the broken stage predicted by the thermal relaxation oscillation (TRO) theory. Compared with other VSP systems, DD Com is a rare system that lies on the expanding phase of the TRO cycle. Until now, only four such systems including DD Com are found in this stage. Thus, this target is another good observational proof of the TRO theory in a very short period region. en dc.language.iso en en dc.publisher IOP Publishing en dc.relation.ispartofseries The astronomical journal en dc.relation.uri http://dx.doi.org/10.1088/0004-6256/140/1/215 en dc.subject binaries: eclipsing en dc.subject stars: evolution en dc.subject stars: individual (DD Com) en dc.title Photometric study of the very short period shallow contact binary DD Comae Berenices en dc.type article en dc.identifier.location Není ve fondu ÚK en dc.identifier.doi 10.1088/0004-6256/140/1/215 dc.identifier.wos 000278691700020

## Files in this item

Files Size Format View

There are no files associated with this item.