On the polarisation of the Red Rectangle optical emission bands

The origin of the narrow optical emission bands seen toward the Red Rectangle is not yet understood. In this paper we investigate further the proposal that these are due to luminescence of large carbonaceous molecules. Polarised signals of several percent could be expected from certain asymmetric molecular rotators. The ESPaDOnS echelle spectrograph mounted at the CFHT was used to obtain high-resolution optical spectropolarimetric data of the Red Rectangle nebular emission. The RRBs at 5800, 5850, and 6615 Angstrom are detected in spectra of the nebular emission 7" and 13" North-East from the central star. The 5826 and 6635 Angstrom RRB are detected only at the position nearest to the central star. For both positions the Stokes Q and U spectra show no unambiguous polarisation signal in any of the RRBs. We derive an upper limit of 0.02% line polarisation for these RRBs. A tentative feature with peak polarisation of 0.05% is seen for the 5800 RRB at 7" offset. However, the Null spectra suggest that this may be an instrumental artifact. The lack of a clear polarisation signal for the five detected RRBs implies that, if the emission is due to luminescence of complex organics, these gas-phase molecular carriers are likely to have a high degree of symmetry, as they do not exhibit a Q-branch in their rotational profile, although this may be modified by statistical effects.Comment: 5 pages, 4 figures, accepted for A&

Sequence structure emission in The Red Rectangle Bands

We report high resolution (R~37,000) integral field spectroscopy of the central region (r<14arcsec) of the Red Rectangle nebula surrounding HD44179. The observations focus on the 5800A emission feature, the bluest of the yellow/red emission bands in the Red Rectangle. We propose that the emission feature, widely believed to be a molecular emission band, is not a molecular rotation contour, but a vibrational contour caused by overlapping sequence bands from a molecule with an extended chromophore. We model the feature as arising in a Polycyclic Aromatic Hydrocarbon (PAH) with 45-100 carbon atoms.Comment: 13 pages, 9 figures, accepted for publication in ApJ. A version of the paper with full resolution figures is available at: http://www.aao.gov.au/local/www/rgs/Sequence-Structure

Varhaiskasvatusta vai -säilytystä?:varhaiskasvatuksen laatu varhaiskasvatuslain ja opettajien työn näkökulmasta

Tiivistelmä. Tutkielmamme aiheena olivat varhaiskasvatuksen laatutekijät varhaiskasvatuslain (540/2018) ja opettajan näkökulmasta. Kiinnostuimme aiheesta varhaiskasvatusta koskevan yhteiskunnallisen keskustelun ja omien kokemustemme myötä; varhaiskasvatus ei aina yllä tavoitteisiinsa ja varhaiskasvatuksen opettajista on pulaa monessa paikassa. Kuitenkin samaan aikaan tiedostetaan laadukkaan varhaiskasvatuksen merkitys lasten hyvinvointia ja oppimista edistävänä tekijänä. Kyselymme kohdistettiin varhaiskasvatuksen opettajille, koska he ovat vastuussa ryhmän toteuttamasta pedagogiikasta. Tavoitteenamme oli selvittää varhaiskasvatuksen opettajana toimivien ajatuksia varhaiskasvatuslain edellyttämästä laadukkaan varhaiskasvatuksen toteutumisesta. Tutkimuskysymykset olivat: 1. Mitkä laatutekijät vaikuttavat varhaiskasvatuslain tavoitteiden toteutumiseen varhaiskasvatuksen opettajan työssä? 2. Mitkä tekijät edistävät tai estävät varhaiskasvatuslain tavoitteiden toteutumista varhaiskasvatuksen opettajan työssä? Varhaiskasvatuksen laatu on kaikkien osatekijöidensä summa. Se koostuu useista pienistä asioista, jotka kaikki vaikuttavat toisiinsa. Kaikki laadun osatekijät rakentuvat ihmisten välisessä vuorovaikutuksessa. Sekä laatu, että varhaiskasvatus ovat käsitteinä aikaan ja paikkaan sidottuja, sillä molempiin vaikuttavat ympäröivän yhteiskunnan arvot ja normit sekä määrittelijän näkökulma. Näin ollen myös laadukkaan varhaiskasvatuksen määritelmä on sidottu siihen kontekstiin, jossa sitä määritellään. Tämän takia tutkielmamme on sidottu suomalaiseen tämänhetkiseen varhaiskasvatukseen. Varhaiskasvatuksen laatua on selvittänyt aikaisemmin kattavasti kansallinen koulutuksen arviointikeskus (Karvi, 2018), joka on luonut varhaiskasvatukselle laatuindikaattorit. Toteutimme tutkielman laadullisena kyselytutkimuksena, jonka aineiston analysoimme teoriaohjaavalla aineistoanalyysilla. Analyysia ohjaavana teoriana toimivat varhaiskasvatuksen laatuindikaattorit. Kyselyyn vastasi 31 opettajana toimivaa, joista 21 täytti varhaiskasvatuksen opettajan kelpoisuusvaatimukset. Tutkielman keskeinen tulos oli se, että varhaiskasvatusta toteutetaan laadultaan hyvin vaihtelevasti. Eniten laatua estäviä tekijöitä löytyi laadun rakennetekijöistä, joista eniten negatiivisia mainintoja saivat liian vähäiset resurssit, henkilöstön poissaolot ja niistä johtuva sijaisten tarve sekä arjen häiriötekijät. Laatua edistävät tekijät puolestaan painottuivat laadun prosessitekijöihin, joista eniten positiivisia mainintoja saivat opettajan ja tiimin ammattitaito sekä monialainen yhteistyö. Toisin sanoen toteutetun pedagogiikan ajateltiin olevan laadukasta, mutta rakenteet sen sijaan koettiin vähemmän laadukkaiksi

Linear/circular spectropolarimetry of diffuse interstellar bands

Context. The identification of the carriers of diffuse interstellar bands (DIBs) remains one of the long-standing mysteries in astronomy. The detection of a polarisation signal in a DIB profile can be used to distinguish between a dust or gas-phase carrier. The polarisation profile can give additional information on the grain or molecular properties of the absorber. In order to detect and measure the linear and circular polarisation of the DIBs we observed reddened lines of sight showing continuum polarisation. For this study we selected two stars HD 197770 and HD 194279. We used high-resolution (R~64.000) spectropolarimetry in the wavelength range from 3700 to 10480 Angstrom with the ESPaDOnS echelle spectrograph mounted at the CFHT. Results. High S/N and high resolution Stokes V (circular), Q and U (linear) spectra were obtained. We constrained upper limits by a factor of 10 for previously observed DIBs. Furthermore, we analysed ~30 additional DIBs for which no spectropolarimetry data has been obtained before. This included the 9577 A DIB and the 8621 A DIB. Conclusions. The lack of polarisation in 45 DIB profiles suggests that none of the absorption lines is induced by a grain-type carrier. The strict upper limits, less than ~0.01%, derived for the observed lines-of-sight imply that if DIBs are due to gas-phase molecules these carriers have polarisation efficiencies which are at least 6 times, and up to 300 times, smaller than those predicted for grain-related carriers.Comment: 6 pages + 13 pages online material, submitted to A&

Mediating punitiveness: understanding public attitudes towards work-related fatality cases

This paper concerns an empirical investigation into public attitudes towards work-related fatality cases, where organizational offenders cause the death of workers or members of the public. This issue is particularly relevant following the introduction of the Corporate Manslaughter and Corporate Homicide Act 2007 into UK law. Here, as elsewhere, the use of criminal law against companies reflects governmental concerns over public confidence in the law’s ability to regulate risk. The empirical findings demonstrate that high levels of public concern over these cases do not translate into punitive attitudes. Such cases are viewed rationally and constructively, and lead to instrumental rather than purely expressive enforcement preferences

The Rotational Excitation Temperature of the λ\lambda6614 Diffuse Interstellar Band Carrier

Analysis of high spectral resolution observations of the $\lambda$6614 diffuse interstellar band (DIB) line profile show systematic variations in the positions of the peaks in the substructure of the profile. These variations -- shown here for the first time -- can be understood most naturally in the framework of rotational contours of large molecules, where the variations are caused by changes in the rotational excitation temperature. We show that the rotational excitation temperature for the DIB carrier is likely significantly lower than the gas kinetic temperature -- indicating that for this particular DIB carrier angular momentum buildup is not very efficient.Comment: Accepted by ApJ Letters; 16 pages, 2 figure

The EDIBLES survey:VI. Searching for time variations of interstellar absorption features

Context. Interstellar absorption observed toward stellar targets changes slowly over long timescales, mainly due to the proper motion of the background target relative to the intervening clouds, such that over time, different parts of the intervening cloud are probed. On longer timescales, the slowly changing physical and chemical conditions in the cloud can also cause variation. Detecting such time variations thus provides an opportunity to study cloud structure.Aims. We searched for systematic variations in the absorption profiles of the diffuse interstellar bands (DIBs) and interstellar atomic and molecular lines by comparing the high-quality data set from the recent ESO diffuse interstellar bands large exploration survey (EDIBLES) to older archival observations, bridging typical timescales of ~10 yr with a maximum timescale of 22 yr.Methods. For 64 EDIBLES targets, we found adequate archival observations. We selected 31 strong DIBs, seven atomic lines, and five molecular lines to focus our search on. We carefully considered various systematic effects and used a robust Bayesian quantitative test to establish which of these absorption features could display significant variations.Results. While systematic effects greatly complicate our search, we find evidence for variations in the profiles of the λλ4727 and 5780 DIBs in a few sightlines. Toward HD 167264, we find a new Ca I cloud component that appears and becomes stronger after 2008. The same sightline furthermore displays marginal, but systematic changes in the column densities of the atomic lines originating from the main cloud component in the sightline. Similar variations are seen toward HD 147933.Conclusions. Our high-quality spectroscopic observations in combination with archival data show that it is possible to probe interstellar time variations on time scales of typically a decade. Despite the fact that systematic uncertainties as well as the generally somewhat lower quality of older data complicate matters, we can conclude that time variations can be made visible, both in atomic lines and DIB profiles for a few targets, but that generally, these features are stable along many lines of sight. We present this study as an archival baseline for future comparisons, bridging longer periods.<br/

Unusually Weak Diffuse Interstellar Bands toward HD 62542

As part of an extensive survey of diffuse interstellar bands (DIBs), we have obtained optical spectra of the moderately reddened B5V star HD 62542, which is known to have an unusual UV extinction curve of the type usually identified with dark clouds. The typically strongest of the commonly catalogued DIBs covered by the spectra -- those at 5780, 5797, 6270, 6284, and 6614 A -- are essentially absent in this line of sight, in marked contrast with other lines of sight of similar reddening. We compare the HD 62542 line of sight with others exhibiting a range of extinction properties and molecular abundances and interpret the weakness of the DIBs as an extreme case of deficient DIB formation in a dense cloud whose more diffuse outer layers have been stripped away. We comment on the challenges these observations pose for identifying the carriers of the diffuse bands.Comment: 20 pages, 4 figures; aastex; accepted by Ap