OAG COMMON PROPER MOTIONS WIDE PAIRS SURVEY

II MEETING DOUBLE STAR OBSERVERS

(Pro-Am)

Sabadell

23-24 October 2010

Xavier Miret / Tòfol TobalObservatori Astronòmic del Garraf (OAG)

www.oagarraf.net

OAG CPM WPS

Project: Search and detection of star pairs with CPM not catalogued yet.

FEATURES:

VISUAL SURVEY. Visual inspection of digitized plates.

SYSTEMATIC SURVEY. Scanning selected areas.

HISTORICAL BACKGROUND

W.J. Luyten Main contribution to

double stars with CPM Year 1979 NLTT > 58.000 stars LDS > 6.000 pairs μ > 0.2 arcsec yr -1

HISTORICAL BACKGROUND

Lépine & Shara SUPERBLINK

software. 2003-2008 LSPM > 122.000 > 1000 doubles μ > 0,15 arcseg yr -1

HISTORICAL BACKGROUND

GARRAF SURVEY (2008).

Search for companions of near 2.000 NLTT between 0,5 and 1 arcseg yr -1

J. A. Caballero &

D. Montes

GARRAF SURVEY LUYTEN STARS

STARS TO STUDY

Stellar population with CPM < 0,15

arcsec yr -1 not studied up to now.

Some pairs with CPM > 0,15 arcsec yr -1

not catalogued before.

COORDINATION & TEAMS

Coordination OAG.

Collaboration AAS. C. Schnabel.

Open information: www.oagarraf.net

OAG CPMWP SURVEY Workshop I & II

February and July 2010, Sabadell (Barcelona)

Tutorials. Method Techniques Practical examples

Resolution of questions. Adjudication sectors. Timetable. Preparation of publications.

Organization: OAG / AAS

CURRENT STATUS

> 500 pairs catalogued up to now. 10 amateur teams on work. Forecast: 12 h RA at the end 2010.

METHOD Loading images POSS I and POSS II (15 x 15 arcmin).

Δt +/- 40 years.

Blinking RGB. Identification of pairs.

Crossing catalogues. USNOB1 and NOMAD1.

Collecting data.

Polar coordinates. Theta/Rho. Aladin vector tool.

LOADING IMAGES

BLINKING RGB

BLINKING RGB

BLINKING RGB

CROSSING CATALOGUES

POLAR COORDINATES Theta/Rho measures on digitized plates. Optimization centroid (Image convolution). Aladin vector tool (Manual path). Reference. I Novalbos communication.

TARGETS Pairs with sep > 5”. No superior limit.

No magnitude limit.

PM > 50 marcsec y -1 in at least one coordinate.

Maximum difference in PM between components < 10 marcsec y -1 in two coordinates. ◄

TARGETS ¿What is the proper motions difference between components? Always < 15% the absolute value of PM Always < 3 X mean error (catalogue value)

DATA COLLECTION 1

IDENTIFICATION. USNOB1 / NOMAD1 / 2MASS / TYCHO2 / HIPPARCOS

RA / DEC J2000 MAGNITUDE V or R PM RA PM DEC PM CATALOGUE SOURCE

DATA COLLECTION 2 THETA RHO EPOCH In case of lack of PM in pairs with

suggestive image blinking we make multiepoch astrometry to support the CPM character.

MULTIEPOCH ASTROMETRY

RESULTS. MAGNITUDE.

MAG R MAG (nº Stars) V MAG (nº Stars)

8 - 10 1 7

10 -12 15 27

12 -14 29 43

14 -16 46 66

16 -18 42 91

18 - 20 20 0

RESULTS PROPER MOTIONSSAMPLE 187 PAIRS

CPM marcsec y-1 Number Stars

50 - 75 90 (48.1 %)

76 - 100 62 (33,1 %)

101 - 125 26 (13.9%)

126 - 150 7 (3.7%)

151 - 200 2 (1%)

PUBLICATION

Revision and cataloguing USNO / WDS: B.D.Mason (USNO).

Electronic publication: USNO/WDS Website Publication: Webb Society DSSC: B.Argyle Professional studies and publications.

J. A.Caballero , D. Montes.

FUTURE Encourage professional and amateur teams

interested so that the project can be improved.

Searching and development a software capable to find the same pairs automatically.

Stellar characterization in at least some subgroups of stars.

Observatori Astronòmic del GarrafParc del Garraf (Barcelona)