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We have detected a broad interstellar absorption band centred close to 7700 Å and with a full width at half-maximum (FWHM) of 176.6 ± 3.9 Å. This is the first such absorption band detected in the optical range and is significantly wider than the numerous diffuse interstellar bands (DIBs). It remained undiscovered until now because it is partially hidden behind the A telluric band produced by O2. The band was discovered using STIS@HST spectra and later detected in a large sample of stars of diverse type (OB stars, BA supergiants, red giants), using further STIS and ground-based spectroscopy. The EW of the band is measured and compared with our extinction and K  i  λλ7667.021, 7701.093 measurements for the same sample. The carrier is ubiquitous in the diffuse and translucent Galactic interstellar medium (ISM) but is depleted in the environment around OB stars. In particular, it appears to be absent or nearly so in sightlines rich in molecular carbon. This behaviour is similar to that of the σ-type DIBs, which originate in the low/intermediate-density UV-exposed ISM but are depleted in the high-density UV-shielded molecular clouds. We also present an update on our previous work on the relationship between E (4405–5495) and R 5495 and incorporate our results into a general model of the ISM. [ABSTRACT FROM AUTHOR]

The first known asteroid with the orbit inside that of Venus is 2020 AV2. This may be the largest member of a new population of small bodies with the aphelion smaller than 0.718 au, called Vatiras. The surface of 2020 AV2 is being constantly modified by the high temperature, by the strong solar wind irradiation that characterizes the innermost region of the Solar system, and by high-energy micrometeorite impacts. The study of its physical properties represents an extreme test-case for the science of near-Earth asteroids. Here, we report spectroscopic observations of 2020 AV2 in the 0.5–1.5-μm wavelength interval. These were performed with the Nordic Optical Telescope and the William Herschel Telescope. Based on the obtained spectra, we classify 2020 AV2 as a Sa-type asteroid. We estimate the diameter of this Vatira to be |$1.50_{-0.65}^{+1.10}$| km by considering the average albedo of A-type and S-complex asteroids (⁠|$p_V=0.23_{-0.08}^{+0.11}$|⁠), and the absolute magnitude (H  = 16.40 ± 0.78 mag). The wide spectral band around 1 μm shows the signature of an olivine-rich composition. The estimated band centre BIC  = 1.08 ± 0.02 μm corresponds to a ferroan olivine mineralogy similar to that of brachinite meteorites. [ABSTRACT FROM AUTHOR]

Evidence for triggered star formation linking three generations of stars is difficult to assemble, as it requires convincingly associating evolved massive stars with H  ii  regions that, in turn, would need to present signs of active star formation. We present observational evidence for triggered star formation relating three generations of stars in the neighbourhood of the star LS II +26 8. We carried out new spectroscopic observations of LS II +26 8, revealing that it is a B0 III-type star. We note that LS II +26 8 is located exactly at the geometric centre of a semi-shell-like H  ii  region complex. The most conspicuous component of this complex is the H  ii  region Sh2-90, which is probably triggering a new generation of stars. The distances to LS II +26 8 and to Sh2-90 are in agreement (between 2.6 and 3 kpc). Analysis of the interstellar medium on a larger spatial scale shows that the H  ii  region complex lies on the north-western border of an extended H2 shell. The radius of this molecular shell is about 13 pc, which is in agreement with what an O9 V star (the probable initial spectral type of LS II +26 8 as inferred from evolutive tracks) can generate through its winds in the molecular environment. In conclusion, the spatial and temporal correspondences derived in our analysis enable us to propose a probable triggered star formation scenario initiated by the evolved massive star LS II +26 8 during its main-sequence stage, followed by stars exciting the H  ii  region complex formed in the molecular shell, and culminating in the birth of young stellar objects around Sh2-90. [ABSTRACT FROM AUTHOR]

At the interface of HII regions and molecular gas, peculiar structures appear, some of them with pillar-like shapes. Understanding their origin is important for characterizing triggered star formation and the impact of massive stars on the interstellar medium. In order to study the molecular environment and influence of radiation on two pillar-like features related to the HII region G46.5-0.2, we performed molecular line observations with the Atacama Submillimeter Telescope Experiment and spectroscopic optical observations with the Isaac Newton Telescope. From the optical observations, we identified the star that is exciting the HII region as spectral type O4-6. The molecular data allowed us to study the structure of the pillars and an HCO+ cloud lying between them. In this HCO+ cloud, which has no well-defined 12CO counterpart, we found direct evidence of star formation: two molecular outflows and two associated near-IR nebulosities. The outflow axis orientation is perpendicular to the direction of the radiation flow from the HII region. Several Class I sources are also embedded in this HCO+ cloud, showing that it is usual that young stellar objects (YSOs) form large associations occupying a cavity bounded by pillars. On the other hand, it was confirmed that the radiation-driven implosion (RDI) process is not occurring in one of the pillar tips. [ABSTRACT FROM AUTHOR]

We analyse a time series of optical spectra of SN 2014J from almost two weeks prior to maximum to nearly four months after maximum. We perform our analysis using the SYNOW code, which is well suited to track the distribution of the ions with velocity in the ejecta. We show that almost all of the spectral features during the entire epoch can be identified with permitted transitions of the common ions found in normal supernovae (SNe) Ia in agreement with previous studies. We show that 2014J is a relatively normal SN Ia. At early times the spectral features are dominated by Si II, S II, Mg II, and Ca II. These ions persist to maximum light with the appearance of Na I and Mg I. At later times iron-group elements also appear, as expected in the stratified abundance model of the formation of normal Type Ia SNe. We do not find significant spectroscopic evidence for oxygen, until 100 d after maximum light. The +100 d identification of oxygen is tentative, and would imply significant mixing of unburned or only slight processed elements down to a velocity of 6000 kms-1. Our results are in relatively good agreement with other analyses in the infrared. We briefly compare SN 2011fe to SN 2014J and conclude that the differences could be due to different central densities at ignition or differences in the C/O ratio of the progenitors. [ABSTRACT FROM AUTHOR]

We present the intensive spectroscopic follow up of the Type Ia supernova (SN Ia) 2014J in the starburst galaxy M82. Twenty-seven optical spectra have been acquired from 2014 January 22 to September 1 with the Isaac Newton and William Herschel Telescopes. After correcting the observations for the recession velocity of M82 and for MilkyWay and host galaxy extinction, we measured expansion velocities from spectral line blueshifts and pseudo-equivalent width of the strongest features in the spectra, which gives an idea on how elements are distributed within the ejecta.We position SN 2014J in the Benetti, Branch et al. andWang et al. diagrams. These diagrams are based on properties of the Si II features and provide dynamical and chemical information about the SN ejecta. The nearby SN 2011fe, which showed little evidence for reddening in its host galaxy, is shown as a reference for comparisons. SN 2014J is a border-line object between the Core-normal and Broad-line groups, which corresponds to an intermediate position between low-velocity gradient and high-velocity gradient objects. SN 2014J follows the R(Si II)-Δm15 correlation, which confirms its classification as a relatively normal SN Ia. Our description of the SN Ia in terms of the evolution of the pseudo-equivalent width of various ions as well as the position in the various diagrams put this specific SN Ia into the overall sample of SN Ia. [ABSTRACT FROM AUTHOR]

We present results obtained towards the HII regions N159, N166, and N132 from the emission of several molecular lines in the 345 GHz window. Using Atacama Submillimetre Telescope Experiment, we mapped a 2.4 arcmin × 2.4 arcmin region towards the molecular cloud N159- W in the 13CO J = 3-2 line and observed several molecular lines at an infrared (IR) peak very close to a massive young stellar object. 12CO and 13CO J = 3-2 were observed towards two positions in N166 and one position in N132. The 13CO J = 3-2 map of the N159-W cloud shows that the molecular peak is shifted south-west compared to the peak of the IR emission. Towards the IR peak, we detected emission from HCN, HNC, HCO+, C2H J = 4-3, CS J = 7-6, and tentatively C18O J = 3-2. This is the first reported detection of these molecular lines in N159-W. The analysis of the C2H line yields more evidence supporting that the chemistry involving this molecular species in compact and/or UC HII regions in the Large Magellanic Cloud should be similar to that in Galactic ones. A non-LTE (local thermodynamic equilibrium) study of the CO emission suggests the presence of both cool and warm gas in the analysed region. The same analysis for the CS, HCO+, HCN, and HNC shows that it is very likely that their emissions arise mainly from warm gas with a density between 5 × 105 to some 106 cm-3. The obtained HCN/HNC abundance ratio greater than 1 is compatible with warm gas and with an star-forming scenario. From the analysis of the molecular lines observed towards N132 and N166, we propose that both regions should have similar physical conditions, with densities of about 103 cm-3. [ABSTRACT FROM AUTHOR]

A pityriasis rubra pilaris-like eruption has been described in patients with dermatomyositis. These patients showed generalized follicular hyperkeratosis and diffuse thickening of the palms and soles. Histopathological findings consisted of keratotic plugging of the follicular infundibulum and features of erector pili myositis. We report on an 18-year-old woman with dermatomyositis. The diagnosis was established by characteristic enzymatic alterations, electromyographic pattern of myositis and the findings in a muscle biopsy, although the patient had no evidence of muscular weakness during a follow-up of 14 years. She developed an erythematous and squamous eruption associated with diffuse palmoplantar keratoderma. Histopathological features consisted of a papillomatous epidermis with spicules of compact eosinophilic hyperkeratosis over the tips of papillae that were not related to hair follicles. Pityriasis rubra pilaris-like eruption seems to be a characteristic although uncommon cutaneous manifestation in dermatomyositis. [ABSTRACT FROM AUTHOR]