Loiano observing site

View of the 60cm telescope of the Loiano observing site

People involved at OAB:

• Scientific staff: R. Merighi, V. Zitelli.

• Technical staff: S. Bernabei, A. De Blasi, I. Bruni, R. Gualandi, R. Mezzini, I. Muzi, P. Salomoni, G. Bregoli, C. Ciattaglia, G. Innocenti.

• Contracts: S. Marinoni

Loiano, observing site of the INAF-Bologna Observatory, is located at 785 m above sea level and is at 37 km from Bologna. We have in Loiano 3 buildings (two hosting the 152cm and 60cm, and the guest house) and 23 hectares of wood. The person in charge of the observing site is V. Zitelli.

The 152cm telescope, dedicated to G.D. Cassini, was built by REOSC and has been operating since 1976. A general description of the Cassini telescope is given in Table 1.

The main focal instruments presently available at the telescope are:

1. A spectrograph/focal reducer: BFOSC (Bologna Faint Object, Spectrograph and Camera), based on transmitting optics ranging from 330 to 1100 nm, equipped with a CCD camera EEV $1340\times1300$ and the possibility to choose between two sets of filters: a standard Johnson-Kron-Cousins system and a Gunn system. An H$\alpha$ filter has been recently made available too.

2. A classical, cooled, five-colour Photoelectric Photometer

3. A two-channel photoelectric Photometer (3 colours).

BFOSC has been the most scheduled instrument, with about 80% of the total allocated time, well matching the seeing and the variable meteo conditions of the Loiano site.

The 60cm telescope was built in 1933 by Zeiss of Jena following the most modern techniques of the time. It was originally equipped with a photographic camera at the F/3 direct focus and was later modified to a f/20 Cassegrain system. At present it is equipped with a 5-colour photometer, and a new camera, a CCD Marconi (series 4710, 13/$\mu$m pixel size, $1055\times1026$ pxs), is mounted at the Cassegrain focus modified with a focal reducer to a f/5.6. It is now permanently used by undergraduate students. A techical report can be found on the web page:

www.bo.astro.it/ loiano/ManualeCCD60cm/ManualeCCD60cm.htm.

In summer the 60cm telescope is also used for outreach activities (see section Outreach and educational activities for more detailed information).

Table 1. Cassini telescope
Mount type	English
Optical configuration	Ritchey-Chrétien
Main mirror diameter	152 cm
Focal ratio (main mirror)	F/3
Cassegrain focus	equivalent focal length 1200 cm
	equivalent focal ratio F/8
	scale 16.8 arcsec/mm
	FOV 70 arcmin