Equations are not being displayed properly on some articles. We hope to have this fixed soon. Our apologies.

Nicholson, M. (2007). Are J0233+0105 and J0233+0106 binary star components?. PHILICA.COM Article number 78.

ISSN 1751-3030  
Log in  
Register  
  1250 Articles and Observations available | Content last updated 24 November, 04:40  
Philica entries accessed 3 441 897 times  


NEWS: The SOAP Project, in collaboration with CERN, are conducting a survey on open-access publishing. Please take a moment to give them your views

Submit an Article or Observation

We aim to suit all browsers, but recommend Firefox particularly:

Are J0233+0105 and J0233+0106 binary star components?

Martin Nicholsonconfirmed user (Independent Researcher)

Published in astro.philica.com

Abstract
The discovery of a new binary star system candidate consisting of two M type dwarfs is described. A variety of astronomical characteristics are used to describe the two components of the system including absolute magnitude, distance, mass, position angle and separation.

Article body

Are J0233+0105 and J0233+0106 binary star components?

Martin Nicholson

Daventry, England

newbinaries@yahoo.co.uk

www.martin-nicholson.info

Abstract

The discovery of a new binary star system candidate consisting of two M type dwarfs is described. A variety of astronomical characteristics are used to describe the two components of the system including absolute magnitude, distance, mass, position angle and separation.

Methodology

Nicholson (2006) described how data mining the LSPM catalog resulted in the discovery of previously unreported double stars. In that paper the high shared proper motion of the two components was used as the main diagnostic tool. However other techniques exist.

A paper by Lepine (2005) links the V band magnitude, as available from the LSPM catalog, the J band magnitude for the matching 2MASS star and the absolute visual magnitude (Mv).

Mv = 0.08 + 3.89(V-J)     for V-J between 0.7 and 1.5

Mv = 2.78 + 2.09(V-J)     for V-J between 1.5 and 3.0

Mv = 1.49 + 2.52(V-J)     for V-J between 3.0 and 4.0

Mv = 2.17 + 2.35(V-J)     for V-J between 4.0 and 5.0

Mv = 4.47 + 1.89(V-J)     for V-J between 5.0 and 9.0

Table 1a - Published data

STAR #

Location

V mag

V-J mag

Total proper motion  (arcsec/yr)

J0233+0105

 

02 33 01.14 

+01 05 39.0

15.50

4.06

0.166

J0233+0106

 

02 33 00.62 

+01 06 07.0

16.09

4.31

0.166

Table 1b - Calculated data

STARS

Position angle (degrees)

Separation (arc seconds)

J0233+0105 and J0233+0106

164.477

29.091

Table 2 - Derived absolute visual magnitude

STAR #

Absolute visual magnitude (Mv)

J0233+0105

 

11.711

J0233+0106

 

12.298

The absolute magnitude (Mv), V band magnitude (V) and distance in parsecs (d) are linked by the standard expression:

V - Mv = 5 log d - 5

Table 3 - Derived distance

STAR #

Distance in parsecs

J0233+0105

57.25

J0233+0106

57.32

Delfosse et al (2000) derived an equation linking absolute magnitude and mass.

Log (Star mass/Solar mass) = 0.001(0.3+1.87Mv+7.614Mv2-1.698Mv3+0.060958Mv4)

Table 4 - Derived mass

STAR #

Mass

J0233+0105

0.306 solar masses

J0233+0106

0.258 solar masses

 Results

When two stars, such as the pair described here, have an almost identical high common-proper motion and are so close together in the sky - both in terms of angular separation (29 arc seconds) and distance from the observer - then it is a reasonable assumption that they are gravitationally bound rather than just a chance line-of-sight arrangement.

Caveats

Photometry provides a much less reliable distance estimate than would be obtained using parallax methods.

Any errors in the estimated V value and quoted J value from the LSPM catalog will impinge on the accuracy of the final values derived from such data.

The latest version of the Washington Double Star Catalog has been checked to confirm that this is a new discovery.

http://ad.usno.navy.mil/wds/wds2006.5/wds2006.5frame1.html

Conclusions

The chosen method - resampling the LSPM catalog for red dwarfs - has generated a  promising candidate for a true binary star. The analysis will now be extended to the entire catalog.

Acknowledgements

This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation.

References

Delfosse, X.; Forveille, T.; Ségransan, D.; Beuzit, J.-L.; Udry, S.; Perrier, C.; Mayor, M., 2000, Accurate masses of very low mass stars. IV. Improved mass-luminosity relations, Astronomy and Astrophysics, v.364, 217-224.

Lepine, Sebastien, 2005, Nearby Stars from the LSPM-North Proper-Motion Catalog. I. Main-Sequence Dwarfs and Giants within 33 Parsecs of the Sun, The Astronomical Journal, Volume 130, Issue 4, pp. 1680-1692.

Nicholson, Martin P., 2006, Unreported High Proper Motion Stars in the LSPM Catalog, Journal of Double Star Observations, vol. 2, no. 2, p. 68-73.

 

 

 

 

 

 

 




Information about this Article
This Article has not yet been peer-reviewed
This Article was published on 29th January, 2007 at 14:28:38 and has been viewed 5884 times.

Creative Commons License
This work is licensed under a Creative Commons Attribution 2.5 License.
The full citation for this Article is:
Nicholson, M. (2007). Are J0233+0105 and J0233+0106 binary star components?. PHILICA.COM Article number 78.


<< Go back Review this ArticlePrinter-friendlyReport this Article



Website copyright © 2006-07 Philica; authors retain the rights to their work under this Creative Commons License and reviews are copyleft under the GNU free documentation license.
Using this site indicates acceptance of our Terms and Conditions.

This page was generated in 0.2550 seconds.