In this paper we present CCD multicolor photometry for 172 globular clusters (GCs), taken from the Bologna catalog (Battistini et al. 1987), in the nearby spiral galaxy M31. The observations were carried out by using the National Astronomical Observatories 60/90 cm Schmidt Telescope in 13 intermediate-band filters, which covered a range of wavelength from 3800 to 10000Å. This provides a multicolor map of M31 in pixels of 1 ′′ .7 × 1 ′′ .7. By aperture photometry, we obtain the spectral energy distributions (SEDs) for these GCs. Using the relationship between the BATC intermediate-band system used for the observations and the UBVRI broad-band system, the magnitudes in the B and V bands are derived.The computed V and B − V are in agreement with the values given by Battistini et al. (1987) and . Finally, by comparing the photometry of each GC with theoretical stellar population synthesis models, we estimate ages of the sample GCs for different metallicities. The results show that nearly all our sample GCs have ages more than 10 9 years, and most of them are around 10 10 years old. Also, we find that GCs fitted by the metal-poor model are generally older than ones fitted by the metal-rich model.

This paper supplements Jiang et al. (2003), who studied 172 M31 globular clusters (GCs) and globular cluster candidates from Battistini et al. (1987) on the basis of integrated photometric measurements in the Beijing-Arizona-Taiwan-Connecticut (BATC) photometric system. Here, we present multicolor photometric CCD data (in the BATC system) for the remaining 39 M31 GCs and candidates. In addition, the ages of 35 GCs are constrained by comparing our accurate photometry with updated theoretical stellar synthesis models. We use photometric measurements from GALEX in the far-and near-ultraviolet and 2MASS infrared JHK s data, in combination with optical photometry. Except for two clusters, the ages of the other sample GCs are all older than 1 Gyr. Their age distribution shows that most sample clusters are younger than 6 Gyr, with a peak at ∼ 3 Gyr, although the 'usual' complement of well-known old GCs (i.e., GCs of similar age as the majority of the Galactic GCs) is present as well.