Open clusters can be the key to deepen our knowledge on various issues involving the structure and evolution of the Galactic disk and details of stellar evolution because a cluster ’ s properties are applicable to all its members .
However the number of open clusters with detailed analysis from high resolution spectroscopy and/or precision photometry imposes severe limitation on studies of these objects .

To expand the number of open clusters with well-defined chemical abundances and fundamental parameters , we investigate the poorly studied , anticenter open cluster Tombaugh 1 .

Using precision uvbyCa H \beta photometry and high resolution spectroscopy , we derive the cluster ’ s reddening , obtain photometric metallicity estimates and , for the first time , present detailed abundance analysis of 10 potential cluster stars ( 9 clump stars and 1 Cepheid ) .

Using radial position from the cluster center and multiple color indices , we have isolated a sample of unevolved probable , single-star members of Tombaugh 1 .
From 51 stars , the cluster reddening is found to be E ( b - y ) = 0.221 \pm 0.006 or E ( B - V ) = 0.303 \pm 0.008 , where the errors refer to the internal standard errors of the mean .
The weighted photometric metallicity from m _ { 1 } and hk is [ Fe/H ] = - 0.10 \pm 0.02 , while a match to the Victoria-Regina Strömgren isochrones leads to an age of 0.95 \pm 0.10 Gyr and an apparent modulus of ( m - M ) = 13.10 \pm 0.10 .
Radial velocities identify 6 giants as probable cluster members and the elemental abundances of Fe , Na , Mg , Al , Si , Ca , Ti , Cr , Ni , Y , Ba , Ce , and Nd have been derived for both the cluster and the field stars .

Tombaugh 1 appears to be a typical inner thin disk , intermediate-age open cluster of slightly subsolar metallicity , located just beyond the solar circle , with solar elemental abundance ratios except for the heavy s-process elements , which are a factor of two above solar .
Its metallicity is consistent with a steep metallicity gradient in the galactocentric region between 9.5 and 12 kpc .
Our study also shows that Cepheid XZ CMa is not a member of Tombaugh 1 , and reveals that this Cepheid presents signs of barium enrichment , making it a probable binary star .