Aims. We identify the young stellar objects (YSOs) present in the vicinity of the W5-E H ii region, and study the influence of this H ii region on the star formation process in its surrounding molecular material.Methods. W5-E has been observed with the Herschel-PACS and -SPIRE photometers, as part of the HOBYS key program; maps have been obtained at 100 μm, 160 μm, 250 μm, 350 μm, and 500 μm. The dust temperature and column density have been obtained by fitting spectral energy distributions (SEDs). Point sources have been detected and measured using PSF photometry with DAOPHOT. Results. The dust temperature map shows a rather uniform temperature, in the range 17.5 K−20 K in the dense condensations or filaments, in the range 21 K−22 K in the photodissociation regions (PDRs), and in the range 24 K−31 K in the direction of the ionized regions. The values in the column density map are rather low, everywhere lower than 10 23 cm −2 , and of the order of a few 10 21 cm −2 in the PDRs. About 8000 M of neutral material surrounds the ionized region, which is low with respect to the volume of this H ii region; we suggest that the exciting stars of the W5-E, W5-W, Sh 201, A and B H ii regions formed along a dense filament or sheet rather than inside a more spherical cloud. Fifty point sources have been detected at 100 μm. Most of them are Class 0/I YSOs. The SEDs of their envelopes have been fitted using a modified blackbody model. These envelopes are cold, with a mean temperature of 15.7 ± 1.8 K.Their masses are in the range 1.3 M -47 M . Eleven of these point sources are candidate Class 0 YSOs. Twelve of these point sources are possibly at the origin of bipolar outflows detected in this region. None of the YSOs contain a massive central object, but a few may form a massive star as they have both a massive envelope and also a high envelope accretion rate. Most of the Class 0/I YSOs are observed in the direction of high column density material, for example in the direction of the massive condensations present at the waist of the bipolar Sh 201 H ii region or enclosed by the bright-rimmed cloud BRC14. The overdensity of Class 0/I YSOs on the borders of the H ii regions present in the field strongly suggests that triggered star formation is at work in this region but, due to insufficient resolution, the exact processes at the origin of the triggering are difficult to determine.

Context. The expansion of H ii regions can trigger the formation of stars. An overdensity of young stellar objects (YSOs) is observed at the edges of H ii regions but the mechanisms that give rise to this phenomenon are not clearly identified. Moreover, it is difficult to establish a causal link between H ii -region expansion and the star formation observed at the edges of these regions. A clear age gradient observed in the spatial distribution of young sources in the surrounding might be a strong argument in favor of triggering. Aims. We aim to characterize the star formation observed at the edges of H ii regions by studying the properties of young stars that form there. We aim to detect young sources, derive their properties and their evolution stage in order to discuss the possible causal link between the first-generation massive stars that form the H ii region and the young sources observed at their edges. Methods. We have observed the Galactic H ii region RCW 120 with Herschel PACS and SPIRE photometers at 70, 100, 160, 250, 350 and 500 µm. We produced temperature and H 2 column density maps and use the getsources algorithm to detect compact sources and measure their fluxes at Herschel wavelengths. We have complemented these fluxes with existing infrared data. Fitting their spectral energy distributions (SEDs) with a modified blackbody model, we derived their envelope dust temperature and envelope mass. We computed their bolometric luminosities and discuss their evolutionary stages. Results. The overall temperatures of the region (without background subtraction) range from 15 K to 24 K. The warmest regions are observed towards the ionized gas. The coldest regions are observed outside the ionized gas and follow the emission of the cold material previously detected at 870 µm and 1.3 mm. The H 2 column density map reveals the distribution of the cold medium to be organized in filaments and highly structured. Column densities range from 7 × 10 21 cm −2 up to 9 × 10 23 cm −2 without background subtraction. The cold regions observed outside the ionized gas are the densest and host star formation when the column density exceeds 2 × 10 22 cm −2 . The most reliable 35 compact sources are discussed. Using exisiting CO data and morphological arguments we show that these sources are likely to be associated with the RCW 120 region. These sources' volume densities range from 2 × 10 5 cm −3 to 10 8 cm −3 . Five sources have envelope masses larger than 50 M and are all observed in high column density regions (>7 × 10 22 cm −2 ). We find that the evolutionary stage of the sources primarily depends on the density of their hosting condensation and is not correlated with the distance to the ionizing star. Conclusions. The Herschel data, with their unique sampling of the far infrared domain, have allowed us to characterize the properties of compact sources observed towards RCW 120 for the first time. We have also been able to determine the envelope temperature, envelope mass and evolutionary stage of these sources. Usin...