Search for gamma-ray emission from the Galactic plane in the longitude range between 37 degrees and 43 degrees

Using the HEGRA system of imaging atmospheric Cherenkov telescopes, a regio n of the Galactic plane (-10 degrees <b<5 degrees, 38 degrees <l<43 degrees ) was surveyed for TeV gamma-ray emission, both from point sources and of d iffuse nature. The region covered includes 15 known pulsars, 6 known supern ova remnants (SNR) and one unidentified EGRET source. No evidence for emiss ion from point sources was detected; upper limits are typically below 0.1 C rab units for the flux above 1 TeV. For the diffuse gamma-ray flux from the Galactic plane, an upper limit of 6.1 x 10(-15) ph cm(-2) s(-1) sr(-1) MeV -1 was derived under the assumption that the spatial distribution measured by the EGRET instrument extends to the TeV regime. This upper flux limit is a factor of about 1.5 larger than the flux expected from the ensemble of g amma-ray unresolved Galactic cosmic ray sources.