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τ9 Eri is a Bp star that was previously reported to be a single-lined spectroscopic binary. Using 17 ESPaDOnS spectropolarimetric (Stokes V) observations, we identified the weak spectral lines of the secondary component and detected a strong magnetic field in the primary. We performed orbital analysis of the radial velocities of both components to find a slightly eccentric orbit (e = 0.129) with a period of 5.95382(2) d. The longitudinal magnetic field (B ℓ) of the primary was measured from each of the Stokes V profiles, with typical error bars smaller than 10 G. Equivalent widths (EWs) of least-squares deconvolution profiles corresponding to only the Fe lines were also measured. We performed frequency analysis of both the B ℓ and EW measurements, as well as of the Hipparcos , SMEI, and TESS photometric data. All sets of photometric observations produce two clear, strong candidates for the rotation period of the Bp star: 1.21 and 3.82 d. The B ℓ and EW measurements are consistent with only the 3.82-d period. We conclude that HD 25267 consists of a late-type Bp star (M = |$3.6_{-0.2}^{+0.1}~\mathrm{ M}_\odot$|⁠ , T = |$12580_{-120}^{+150}$|  K) with a rotation period of 3.82262(4) d orbiting with a period of 5.95382(2) d with a late-A/early-F type secondary companion (M = 1.6 ± 0.1 M⊙, T = |$7530_{-510}^{+580}$|  K). The Bp star's magnetic field is approximately dipolar with i = 41 ± 2°, β = 158 ± 5°, and B d = 1040 ± 50 G. All evidence points to the strong 1.209912(3)-d period detected in photometry, along with several other weaker photometric signals, as arising from g-mode pulsations in the primary. [ABSTRACT FROM AUTHOR]

Rapidly rotating early-type stars with strong magnetic fields frequently show H α emission originating in centrifugal magnetospheres (CMs), circumstellar structures in which centrifugal support due to magnetically enforced corotation of the magnetically confined plasma enables it to accumulate to high densities. It is not currently known whether the CM plasma escapes via centrifugal breakout (CB), or by an unidentified leakage mechanism. We have conducted the first comprehensive examination of the H α emission properties of all stars currently known to display CM-pattern emission. We find that the onset of emission is dependent primarily on the area of the CM, which can be predicted simply by the value B K of the magnetic field at the Kepler corotation radius R K. Emission strength is strongly sensitive to both CM area and B K. Emission onset and strength are not dependent on effective temperature, luminosity, or mass-loss rate. These results all favour a CB scenario; however, the lack of intrinsic variability in any CM diagnostics indicates that CB must be an essentially continuous process, i.e. it effectively acts as a leakage mechanism. We also show that the emission profile shapes are approximately scale-invariant, i.e. they are broadly similar across a wide range of emission strengths and stellar parameters. While the radius of maximum emission correlates closely as expected to R K, it is always larger, contradicting models that predict that emission should peak at R K. [ABSTRACT FROM AUTHOR]

Recent BRITE-Constellation space photometry of the slowly rotating, magnetic β Cep pulsator ξ1 CMa permits a new analysis of its pulsation properties. Analysis of the two-colour BRITE data reveals the well-known single pulsation period of 0.209 d, along with its first and second harmonics. A similar analysis of SMEI and TESS observations yields compatible results, with the higher precision TESS observations also revealing several low-amplitude modes with frequencies below 5 d−1; some of these are likely g modes. The phase lag between photometric and radial velocity maxima – equal to 0.334 cycles – is significantly larger than the typical value of 1/4 observed in other large-amplitude β Cep stars. The phase lag, as well as the strong dependence of phase of maximum light on wavelength, can be reconciled with seismic models only if the dominant mode is the fundamental radial mode. We employ all published photometric and radial velocity measurements, spanning over a century, to evaluate the stability of the pulsation period. The O − C diagram exhibits a clear parabolic shape consistent with a mean rate of period change |$\dot{P}=0.34\pm 0.02$|  s cen−1. The residuals from the best-fitting parabola exhibit scatter that is substantially larger than the uncertainties. In particular, dense sampling obtained during the past ∼20 yr suggests more complex and rapid period variations. Those data cannot be coherently phased with the mean rate of period change, and instead require |$\dot{P}\sim 0.9$|  s cen−1. We examine the potential contributions of binarity, stellar evolution, and stellar rotation and magnetism to understand the apparent period evolution. [ABSTRACT FROM AUTHOR]

It was recently claimed that the magnetic O-type star HD 54879 exhibits important radial velocity variability indicative of its presence in a spectroscopic binary. More remarkably, it was furthermore reported that the star underwent a short, sudden variation in spectral type and magnetic field. In this letter, we examine new Narval and ESPaDOnS data of this star in addition to the previously published FORS2 data and conclude that both the reported velocity variations and the sudden spectral and magnetic changes are spurious. [ABSTRACT FROM AUTHOR]

Background: 'Braun' is an illegal injectable dihydrocodeinone‐enriched drug mixture of semi‐synthetic opioids. It is prepared by palladium‐catalysed hydrogenation from codeine‐containing tablets. Objective: We aimed to characterize the dermatologic consequences of long‐term abuse of 'Braun'. Methods: Skin biopsies of two long‐term 'Braun' abusers were evaluated histopathologically, immunohistochemically and ultrastructurally. Palladium skin content was assessed by X‐ray fluorescence (XRF) spectrometry. Results: Both patients showed generalized diffuse dark blue–grey hyperpigmentation of the skin. In both, an abnormal population of cells containing intracytoplasmic brownish granular material was identified in the papillary dermis by light microscopy. Electron microscopy revealed a dense and minimally structured material that predominantly accumulated in macrophages, fibroblasts and vascular endothelial cells. XRF analysis confirmed elevated levels of palladium in the patient's skin in comparison to healthy controls. Conclusion: Long‐term abuse of palladium‐contaminated dihydrocodeinone ('Braun') results in excessive accumulation of granular material in various dermal cell types and causes generalized diffuse skin hyperpigmentation. [ABSTRACT FROM AUTHOR]

Various surveys focusing on the magnetic properties of intermediate-mass main-sequence (MS) stars have been previously carried out. One particularly puzzling outcome of these surveys is the identification of a dichotomy between the strong (⁠|${\gtrsim }100\, {\rm G}$|⁠), organized fields hosted by magnetic chemically peculiar (mCP) stars and the ultraweak (⁠|${\lesssim }1\, {\rm G}$|⁠) fields associated with a small number of non-mCP MS stars. Despite attempts to detect intermediate strength fields (i.e. those with strengths ≳10 and |${\lesssim }100\, {\rm G}$|⁠), remarkably few examples have been found. Whether this so-called magnetic desert, separating the stars hosting ultraweak fields from the mCP stars truly exists has not been definitively answered. In 2007, a volume-limited spectropolarimetric survey of mCP stars using the MuSiCoS spectropolarimeter was initiated to test the existence of the magnetic desert by attempting to reduce the biases inherent in previous surveys. Since then, we have obtained a large number of ESPaDOnS and NARVAL Stokes V measurements allowing this survey to be completed. Here, we present the results of our homogeneous analysis of the rotational periods (inferred from photometric and magnetic variabilities) and magnetic properties (dipole field strengths and obliquity angles) of the 52 confirmed mCP stars located within a heliocentric distance of |$100\, {\rm pc}$|⁠. No mCP stars exhibiting field strengths |${\lesssim }300\, {\rm G}$| are found within the sample, which is consistent with the notion that the magnetic desert is a real property and not the result of an observational bias. Additionally, we find evidence of magnetic field decay, which confirms the results of previous studies. [ABSTRACT FROM AUTHOR]

We present the first results of a volume-limited survey of main-sequence (MS) magnetic chemically peculiar (mCP) stars. The sample consists of all identified intermediate-mass MS stars (mCP and non-mCP) within a heliocentric distance of |$100\, {\rm pc}$| as determined using Hipparcos parallaxes. The two populations are compared in order to determine the unique properties that allow a small fraction of MS stars with masses |${\gtrsim }1.4\, \mathrm{M}_\odot$| to host strong, large-scale magnetic fields. A total of 52 confirmed mCP stars are identified using published magnetic, spectroscopic, and photometric observations along with archived and newly obtained spectropolarimetric (Stokes V) observations. We derive the fundamental parameters (effective temperatures, luminosities, masses, and evolutionary states) of the mCP and non-mCP populations using homogeneous analyses. A detailed analysis of the mCP stars is performed using the llmodels code, which allows observed spectral energy distributions to be modelled while incorporating chemical peculiarities and magnetic fields. The surface gravities and mean chemical abundances are derived by modelling averaged spectra using the gssp and zeeman spectral synthesis codes. Masses and stellar ages are derived using modern, densely calculated evolutionary model grids. We confirm a number of previously reported evolutionary properties associated with mCP stars including a conspicuously high incidence of middle-aged MS stars with respect to the non-mCP subsample; the incidence of mCP stars is found to sharply increase with mass from 0.3 per cent at |$1.5\, \mathrm{M}_\odot$| to ≈11 per cent at |$3.8\, \mathrm{M}_\odot$|⁠. Finally, we identify clear trends in the mean photospheric chemical abundances with stellar age. [ABSTRACT FROM AUTHOR]

The Rozprza stronghold functioned as a seat of a noble family since at least the early14 th century AD in the form of the motte-and-bailey residence. The remains of the residence are situated in the central part of mid-Luciąża River valley, on the river terrace remnant adjoining a strongly expanding floodplain. The situation and state of preservation give a unique opportunity to conduct research that explain the construction process, detailed history of the medieval moat and palaeoenvironmental reconstruction of the valley floor. Radiocarbon and dendrochronological dating and analysis of artefacts confirmed 14th century age of the moat. Organic deposits (gyttja, peat and organic mud) of moat fill allowed for a set of multiproxy analyses based on sediment cores. The research results indicate shallow water with brief episodes of in-wash in the first stage (13 th -14th c. AD), followed by a transformation into telmatic habitat in the second phase of the moat development from 16 th -17th c. AD. The deposition of overbank alluvium took place within the moat ditch system as late as the 18th and/or 19th c. AD. We studied the development of this moat environment in the context of valley floor changes. [ABSTRACT FROM AUTHOR]

The rotational and magnetic properties of many magnetic hot stars are poorly characterized, therefore the Magnetism in Massive Stars and Binarity and Magnetic Interactions in various classes of Stars collaborations have collected extensive high-dispersion spectropolarimetric data sets of these targets. We present longitudinal magnetic field measurements (Bz) for 52 early B-type stars (B5-B0), with which we attempt to determine their rotational periods Prot. Supplemented with high-resolution spectroscopy, low-resolution Dominion Astrophysical Observatory circular spectropolarimetry, and archival Hipparcos photometry, we determined Prot for 10 stars, leaving only five stars for which Prot could not be determined. Rotational ephemerides for 14 stars were refined via comparison of new to historical magnetic measurements. The distribution of Prot is very similar to that observed for the cooler Ap/Bp stars. We also measured v sin i and vmac for all stars. Comparison to non-magnetic stars shows that v sin i is much lower for magnetic stars, an expected consequence of magnetic braking. We also find evidence that vmac is lower for magnetic stars. Least-squares deconvolution profiles extracted using single-element masks revealed widespread, systematic discrepancies in (Bz) between different elements: this effect is apparent only for chemically peculiar stars, suggesting it is a consequence of chemical spots. Sinusoidal fits to H line (Bz) measurements (which should be minimally affected by chemical spots), yielded evidence of surface magnetic fields more complex than simple dipoles in six stars for which this has not previously been reported; however, in all six cases, the second- and third-order amplitudes are small relative to the first-order (dipolar) amplitudes. [ABSTRACT FROM AUTHOR]

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