| dc.description.abstract | Hundreds of thousands star clusters were suggested to exist in the Galactic disk, but so far only a few thousands had been catalogued, all in the solar neighborhood (less than 2 kpc).
We therefore aim to use Pan-STARRS 3π data with its wide-field sky and sensitive camera to search for and to characterize star clusters.
This thesis conducted a pilot study using a star-counting algorithm to identify stellar density enhancements toward the Galactic anti-center.
The detection rate of known star clusters in this region with radii less than 10′ from the algorithm used was approximately 83%.
In the field of 20 × 20 degrees, we identified 491 stellar cluster candidates, 50 of which were matched with known star cluster catalog.
The remaining 441 candidates were characterized with radius, reddening, distance, age, and lowest mass members, along with PPMXL proper motions and 2MASS and Pan-STARRS multi-band photometry.
The revised star cluster sample was estimated to be complete up to a heliocentric distance of 5 kpc toward the Galactic anti-center.
Moreover, this sample allowed us to estimate the separation between Sagittarius and Perseus arms was about 3.2 kpc with 0.2 kpc uncertainty and the widths of the nearby spiral arms---Sagittarius, Orion, and Perseus---with the full-width-half-maximum to be 1.4±0.1, 1.6±0.1, and 3.3±0.2 kpc, respectively.
In the early study, one star cluster G144.9+0.4 identified from the 2MASS point sources catalog was characterized.
We showed that the cluster at a distance of about 1 kpc is physically associated with the Cam OB1 association with an age of 1-2 Myr.
Pre-main sequence stars were identified, on the basis of photometric and proper motion data.
A total of 91 additional OB star candidates were photometrically and kinematically found in subgroups 1A and 1B, a significant increase from the currently known 43 OB stars.
The OB members showed an age spread that indicated a sustained star formation for at least the last 10-15 Myr.
The young cluster G144.9+0.4 represented the latest episode of sequential star formation in this cloud complex.
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