The Extinction Properties of and Distance to the Highly Reddened Type Ia Supernova SN 2012cu

Correction of Type Ia Supernova brightnesses for extinction by dust has proven to be a vexing problem. Here we study the dust foreground to the highly reddened SN 2012cu, which is projected onto a dust lane in the galaxy NGC 4772. The analysis is based on multi-epoch, spectrophotometric observations spanning 3,300 - 9,200 {\AA}, obtained by the Nearby Supernova Factory. Phase-matched comparison of the spectroscopically twinned SN 2012cu and SN 2011fe across 10 epochs results in the best-fit color excess of (E(B-V), RMS) = (1.00, 0.03) and total-to-selective extinction ratio of (RV , RMS) = (2.95, 0.08) toward SN 2012cu within its host galaxy. We further identify several diffuse interstellar bands, and compare the 5780 {\AA} band with the dust-to-band ratio for the Milky Way. Overall, we find the foreground dust-extinction properties for SN 2012cu to be consistent with those of the Milky Way. Furthermore we find no evidence for significant time variation in any of these extinction tracers. We also compare the dust extinction curve models of Cardelli et al. (1989), O'Donnell (1994), and Fitzpatrick (1999), and find the predictions of Fitzpatrick (1999) fit SN 2012cu the best. Finally, the distance to NGC4772, the host of SN 2012cu, at a redshift of z = 0.0035, often assigned to the Virgo Southern Extension, is determined to be 16.6$\pm$1.1 Mpc. We compare this result with distance measurements in the literature.Comment: 48 pages, 13 figures. Accepted for publication in The Astrophysical Journal. The spectral time series data presented in this article can be found at http://snfactory.lbl.gov/snf/data

Improving Cosmological Distance Measurements Using Twin Type Ia Supernovae

We introduce a method for identifying "twin" Type Ia supernovae, and using them to improve distance measurements. This novel approach to Type Ia supernova standardization is made possible by spectrophotometric time series observations from the Nearby Supernova Factory (SNfactory). We begin with a well-measured set of supernovae, find pairs whose spectra match well across the entire optical window, and then test whether this leads to a smaller dispersion in their absolute brightnesses. This analysis is completed in a blinded fashion, ensuring that decisions made in implementing the method do not inadvertently bias the result. We find that pairs of supernovae with more closely matched spectra indeed have reduced brightness dispersion. We are able to standardize this initial set of SNfactory supernovae to 0.083 +/- 0.012 magnitudes, implying a dispersion of 0.072 +/- 0.010 magnitudes in the absence of peculiar velocities. We estimate that with larger numbers of comparison SNe, e.g, using the final SNfactory spectrophotometric dataset as a reference, this method will be capable of standardizing high-redshift supernovae to within 0.06-0.07 magnitudes. These results imply that at least 3/4 of the variance in Hubble residuals in current supernova cosmology analyses is due to previously unaccounted-for astrophysical differences among the supernovaeComment: 37 pages, 9 figures, 5 tables. Accepted for publication in ApJ. Fixed typo in arXiv abstrac

The supernova CSS121015:004244+132827: a clue for understanding super-luminous supernovae

We present optical photometry and spectra of the super luminous type II/IIn supernova CSS121015:004244+132827 (z=0.2868) spanning epochs from -30 days (rest frame) to more than 200 days after maximum. CSS121015 is one of the more luminous supernova ever found and one of the best observed. The photometric evolution is characterized by a relatively fast rise to maximum (~40 days in the SN rest frame), and by a linear post-maximum decline. The light curve shows no sign of a break to an exponential tail. A broad Halpha is first detected at ~ +40 days (rest-frame). Narrow, barely-resolved Balmer and [O III] 5007 A lines, with decreasing strength, are visible along the entire spectral evolution. The spectra are very similar to other super luminous supernovae (SLSNe) with hydrogen in their spectrum, and also to SN 2005gj, sometimes considered a type Ia interacting with H-rich CSM. The spectra are also similar to a subsample of H-deficient SLSNe. We propose that the properties of CSS121015 are consistent with the interaction of the ejecta with a massive, extended, opaque shell, lost by the progenitor decades before the final explosion, although a magnetar powered model cannot be excluded. Based on the similarity of CSS121015 with other SLSNe (with and without H), we suggest that the shocked-shell scenario should be seriously considered as a plausible model for both types of SLSN.Comment: 17 pages, 10 figures and 5 tables. In press to MNRAS. This version matches the accepted one. Main conclusions are unchange

Against dichotomies: on mature care and self-sacrifice in care ethics

Introduction: In previous issues of this journal Carol Gilligan’s original concept of mature care has been conceptualized by several (especially Norwegian) contributors. This has resulted in a dichotomous view of self and other, and of self-care and altruism, in which any form of self-sacrifice is rejected. Although this interpretation of Gilligan seems to be quite persistent in care ethical theory, it does not seem to do justice to either Gilligan’s original work or the tensions experienced in contemporary nursing practice. Discussion: A close reading of Gilligan’s concept of mature care leads to a view that differs radically from any dichotomy of self-care and altruism. Instead of a dichotomous view, a dialectical view on self and other is proposed that builds upon connectedness and might support a care ethical view of nursing that is more consistent with Gilligan’s own critical insights such as relationality and a practice-based ethics. A concrete case taken from nursing practice shows the interconnectedness of professional and personal responsibility. This underpins a multilayered, complex view of self-realization that encompasses sacrifices as well. Conclusion: When mature care is characterized as a practice of a multilayered connectedness, caregivers can be acknowledged for their relational identity and nursing practices can be recognized as multilayered and interconnected. This view is better able to capture the tensions that are related to today’s nursing as a practice, which inevitably includes sacrifices of self. In conclusion, a further discussion on normative conceptualizations of care is proposed that starts with a non-normative scrutiny of caring practices

A qualitative focus group study on legal experts’ views regarding euthanasia requests based on an advance euthanasia directive

Background: The Dutch Euthanasia law permits euthanasia in patients with advanced dementia lacking decisional capacity based on advance euthanasia directives. Nevertheless, physicians encounter difficulties assessing the criteria for due care in such cases. This study explores the perspectives of legal experts on the fulfillment of these criteria and the potential for additional legal guidance to support physicians’ decision-making processes. Methods: A qualitative study was conducted with legal experts. Two focus group sessions were conducted. The data analysis was conducted iteratively, with the data being interpreted using thematic content analysis and the framework method. Results: Participants emphasize the importance of considering the patient’s current wishes and informing them about the limitations of advance euthanasia directives. While representatives and healthcare professionals can assist in interpreting wishes, the final decision regarding euthanasia rests with the physician. The participants also discuss the challenges posed by pre-recorded wishes due to changing preferences. Furthermore, they present different views on the value of life wishes of patients with advanced dementia. While some participants prioritize life wishes over advance euthanasia directives, others question whether such expressions still reflect their will. Participants find it essential to assess unbearable suffering in the context of the current situation. Participants acknowledge the necessity to interpret advance euthanasia directives but also current expressions and they entrust this interpretation to physicians, viewing them as the primary authority, despite consulting multiple sources. Conclusions: The Dutch Euthanasia law’s due care criteria are open norms –which are open in substance and require further elaboration, mostly determined on a case-by-case basis to the field standards of the profession–, placing the responsibility on physicians to interpret advance euthanasia directives and patient expressions. Despite potential support from various sources of information, there is limited additional legal guidance available to assist physicians in making decisions.</p

75-plussers met een doodswens zonder dat ze ernstig ziek zijn

Begin 2020 presenteerden wij het onderzoeksrapport ‘Perspectieven op de doodswens van ouderen die niet ernstig ziek zijn: de mensen en de cijfers’.1 Aanleiding voor onze studie was het voortgaande debat over de vraag of het mogelijk moet zijn om hulp bij zelfdoding te verlenen aan ouderen die hun leven als ‘voltooid’ beschouwen zonder dat zij ernstig ziek zijn

SN2012dn from early to late times: 09dc-like supernovae reassessed

As a candidate ‘super-Chandrasekhar’ or 09dc-like Type Ia supernova (SN Ia), SN 2012dn shares many characteristics with other members of this remarkable class of objects but lacks their extraordinary luminosity. Here, we present and discuss the most comprehensive optical data set of this SN to date, comprised of a densely sampled series of early-time spectra obtained within the Nearby Supernova Factory project, plus photometry and spectroscopy obtained at the Very Large Telescope about 1 yr after the explosion. The light curves, colour curves, spectral time series, and ejecta velocities of SN 2012dn are compared with those of other 09dc-like and normal SNe Ia, the overall variety within the class of 09dc-like SNe Ia is discussed, and new criteria for 09dc-likeness are proposed. Particular attention is directed to additional insight that the late-phase data provide. The nebular spectra show forbidden lines of oxygen and calcium, elements that are usually not seen in late-time spectra of SNe Ia, while the ionization state of the emitting iron plasma is low, pointing to low ejecta temperatures and high densities. The optical light curves are characterized by an enhanced fading starting ∼60 d after maximum and very low luminosities in the nebular phase, which is most readily explained by unusually early formation of clumpy dust in the ejecta. Taken together, these effects suggest a strongly perturbed ejecta density profile, which might lend support to the idea that 09dc-like characteristics arise from a brief episode of interaction with a hydrogen-deficient envelope during the first hours or days after the explosion

SCALA: In situ calibration for integral field spectrographs

International audienceThe scientific yield of current and future optical surveys is increasingly limited by systematic uncertainties in the flux calibration. This is the case for Type Ia supernova (SN Ia) cosmology programs, where an improved calibration directly translates into improved cosmological constraints. Current methodology rests on models of stars. Here we aim to obtain flux calibration that is traceable to state-of-the-art detector-based calibration. We present the SNIFS Calibration Apparatus (SCALA), a color (relative) flux calibration system developed for the SuperNova Integral Field Spectrograph (SNIFS), operating at the University of Hawaii 2.2 m (UH 88) telescope. By comparing the color trend of the illumination generated by SCALA during two commissioning runs, and to previous laboratory measurements, we show that we can determine the light emitted by SCALA with a long-term repeatability better than 1%. We describe the calibration procedure necessary to control for system aging. We present measurements of the SNIFS throughput as estimated by SCALA observations. The SCALA calibration unit is now fully deployed at the UH\,88 telescope, and with it color-calibration between 4000 {\AA} and 9000 {\AA} is stable at the percent level over a one-year baseline

Euthanasia and Physician-Assisted Suicide in Patients with Multiple Geriatric Syndromes

Importance: The Dutch Regional Euthanasia Review Committees (RTEs) reviewed and reported an increasing number of cases of euthanasia and physician-Assisted suicide (EAS) requested by older people with multiple geriatric syndromes (MGS). Knowledge of the characteristics of cases of EAS for MGS is important to facilitate societal debat