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New candidate planetary nebulae in M81

L. Magrini·M. Perinotto·R. L. M. Corradi·A. Mampaso
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Abstract

A 34 x 34 arcmin field centred on the spiral galaxy M81 has been searched for emission-line objects using the prime focus wide field camera (WFC) of the 2.54 m Isaac Newton Telescope (La Palma, Spain). A total of 171 candidate planetary nebulae (PNe) are found, 54 of which are in common with the ones detected by Jacoby et al. (1989). The behaviour of PNe excitation as a function of galactocentric distance is examined, and no significant variations are found. The PNe luminosity function is built for the disk and bulge of M81, separately. A distance modulus of 27.92+-0.23 mag is found for disk PNe, in good agreement with previous distance measurements for M81 (Jacoby et al. 1989; Huterer et al. 1995).

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L. Magrini, M. Perinotto, R. L. M. Corradi, A. Mampaso. 2001-09-25. New candidate planetary nebulae in M81. https://doi.org/10.1051/0004-6361%3A20011301

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