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We present a list of weak emission lines (WELs) observed in a sharp-lined B3 V star {iota} Her (HD 160762) using high resolution (R = 65000) and high SN (~1300) spectral data. The list covers a spectral region between 4900A and 10000A. We register 207 WELs in this star and identified 190 lines including ten ions (nine elements). Emission lines of C II, N I, Cr II, Mn II, and Ni II have been identified among normal B-type stars for the first time. 17 emission lines remain unidentified. We compare our list with the published list of WELs for 3 Cen A (Wahlgren and Hubrig 2004) and found that numbers of detected emission lines reflect differences in abundance between these two stars. We detect 13 C I emission lines in iota Her (normal in C), while only one C I emission line is found in 3 Cen A (deficient in C). Many emission lines of P II and Cu II have been detected in 3 Cen A (overabundant in both P and Cu), while no emission line of these ions has been found in {iota} Her. Many emission lines of Fe II are visible in the shorter wavelength side of 6000 A in iota Her, while these emission lines are missing in 3 Cen A. Close inspections of spectral data of 3 Cen A reveal that apparently missing Fe II lines appear as absorption lines in this star. Because these two stars have nearly the same atmospheric parameters (Teff and log g), a physical interpretation which is independent on these two parameters is needed to account for this observation.
Previously unrecognized weak emission lines originating from high excitation states of Si II (12.84 eV) and Al II (13.08 eV) are detected in the red region spectra of slowly rotating early B-type stars. We surveyed high resolution spectra of 35 B-typ
On the basis of an extensive new spectroscopic survey of Galactic O stars, we introduce the Ofc category, which consists of normal spectra with C III lambdalambda4647-4650-4652 emission lines of comparable intensity to those of the Of defining lines
A small subset of optically selected radio-quiet quasars showing weak or no emission lines may turn out to be the elusive radio-quiet BL Lac objects, or simply be radio-quiet QSOs with a still-forming/shielded broad line region (BLR). High polarisati
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The mass, origin and evolutionary stage of the binary system LB-1 has been the subject of intense debate, following the claim that it hosts an $sim$70$M_{odot}$ black hole, in stark contrast with the expectations for stellar remnants in the Milky Way