Aims.
Our goal is to investigate the structure, elemental abundances, physical conditions, and the immediate surroundings of supernova remnant 0540-69.3 in the Large Magellanic Cloud.
Methods.
...Imaging in O
III
and spectroscopic studies through various slits were carried out using European Souther Observatory’s Very Large and New Technology Telescopes. Densities, temperatures, and abundances were estimated applying nebular analysis for various parts of the remnant.
Results.
Several new spectral lines are identified, both from ejecta embedded in the pulsar-wind nebula, and in interstellar clouds shocked by the supernova blast wave. For the filaments in the pulsar-wind nebula, all lines are redshifted by 440 ± 80 km s
−1
with respect to the rest frame of the host galaxy, and a 3D representation of the O
III
emission displays a symmetry axis of ring-like structures which could indicate that the pulsar shares the same general redshift as the central supernova ejecta. We note that O
II
, S
II
, Ar
III
, and H
β
share a common more compact structure than O
III
, and possibly Ne
III
. The average O
III
temperature for the filaments in the pulsar-wind nebula is 23 500 ± 1800 K, and the electron density derived from S
II
is typically ∼ 10
3
cm
−3
. By mass, the relative elemental abundances of the shocked ejecta in the pulsar-wind nebula are O : Ne : S : Ar ≈ 1 : 0.07 : 0.10 : 0.02, consistent with explosion models of 13 − 20
M
⊙
progenitors, and similar to that of SN 1987A, as is also the explosive mixing of hydrogen and helium into the center. From H
β
and He
I
λ
5876, the mass ratio of He/H in the center is estimated to be in excess of ∼0.8. The rapid cooling of the shocked ejecta could potentially cause variations in the relative abundances if the ejecta are not fully microscopically mixed, and this is highlighted for S/O for the period 1989–2006. Also, O
III
is seen in presumably freely coasting photoionized ejecta outside the pulsar-wind nebula at inferred velocities out to well above 2000 km s
−1
, and in projection, O
III
is seen out to ∼10″ from the pulsar. This was used to estimate that the pulsar age is ≈1200 years. The freely coasting O
III
-emitting ejecta have a strictly nonspherical distribution, and their mass is estimated to be ∼0.12
M
⊙
. A possible outer boundary of oxygen-rich ejecta is seen in O
II
λλ
3726,3729 at ∼2000 − 2100 km s
−1
. Four filaments of a shocked interstellar medium are identified, and there is a wide range in the degree of ionization of iron, from Fe
+
to Fe
13+
. One filament belongs to a region also observed in X-rays, and another one has a redshift of 85 ± 30 km s
−1
relative to the host. From this we estimate that the electron density of the O
III
-emitting gas is ∼ 10
3
cm
−3
, and that the line of the most highly ionized ion, Fe
XIV
λ
5303, comes from an evaporation zone in connection with the radiatively cooled gas emitting, for example, O
III
, and not from immediately behind the blast wave. We do not find evidence for nitrogen-enriched ejecta in the southwestern part of the remnant, as was previously suggested. Emission in this region is instead from a severely reddened H
II
-region.
Aims. This study aims at constraining the origin of the nearby Type Ia supernovae (SNe), 2011fe and 2014J. The two most favoured scenarios for triggering the explosion of the white dwarf supernova ...progenitor is either mass loss from a non-degenerate companion or merger with another white dwarf. In the former, there could be a significant amount of leftover material from the companion at the centre of the supernova. Detecting such material would therefore favour the single-degenerate scenario. Methods. The left-over material from a possible non-degenerate companion can reveal itself after about one year, and in this study such material was searched for in the spectra of SN 2011fe (at 294 days after the explosion) using the Large Binocular Telescope and for SN 2014J using the Nordic Optical Telescope (315 days past explosion). The observations were interpreted using numerical models simulating the expected line emission from ablated material from the companion star. The spectral lines sought for are Hα, O I λ6300, and Ca II λλ7291,7324, and the expected width of these lines is ~1000 km s-1, which in the case of the Ca II lines blend to a broader feature. Results. No signs of Hα, O I λ6300, or Ca II λλ7291, 7324 could be traced for in any of the two supernovae. When systematic uncertainties are included, the limits on hydrogen-rich ablated gas are 0.003 M⊙ in SN 2011fe and 0.0085 M⊙ in SN 2014J, where the limit for SN 2014J is the second lowest ever, and the limit for SN 2011fe is a revision of a previous limit. Limits are also put on helium-rich ablated gas, and here limits from O I λ6300 provide the upper mass limits 0.002 M⊙ and 0.005 M⊙ for SNe 2011fe and 2014J, respectively. These numbers are used in conjunction with other data to argue that these supernovae can stem from double-degenerate systems or from single-degenerate systems with a spun-up/spun-down super-Chandrasekhar white dwarf. For SN 2011fe, other types of hydrogen-rich donors can very likely be ruled out, whereas a main-sequence donor system with large intrinsic separation is still possible for SN 2014J. Helium-rich donor systems cannot be ruled out for any of the two supernovae, but the expected short delay time for such progenitors makes this possibility less likely, especially for SN 2011fe. Published data for SNe 1998bu, 2000cx, 2001el, 2005am, and 2005cf are used to constrain their origin. We emphasise that the results of this study depend on the sought-after lines emerging unattenuated from the central regions of the nebula. Detailed radiative transfer calculations with longer line lists than are presently used are needed to confirm that this is, in fact, true. Finally, the broad lines of SNe 2011fe and 2014J are discussed, and it is found that the Ni II λ7378 emission is redshifted by ~+1300 kms-1, as opposed to the known blueshift of ~−1100 kms-1 for SN 2011fe. Fe II λ7155 is also redshifted in SN 2014J. SN 2014J belongs to a minority of SNe Ia that both have a nebular redshift of Fe II λ7155 and Ni II λ7378, and a slow decline of the Si II λ6355 absorption trough just after B-band maximum.
ABSTRACT
We present observations of the pulsar-wind nebula (PWN) region of SNR 0540-69.3. The observations were made with the Atacama Compact Array (ACA) in Bands 4 and 6. We also add radio ...observations from the Australia Compact Array at 3 cm. For 1.449–233.50 GHz, we obtain a synchrotron spectrum $F_{\nu } \propto \nu ^{-\alpha _{\nu }}$, with the spectral index αν = 0.17 ± 0.02. To conclude how this joins the synchrotron spectrum at higher frequencies, we include hitherto unpublished AKARI mid-infrared data, and evaluate published data in the ultraviolet (UV), optical, and infrared (IR). In particular, some broad-band filter data in the optical must be discarded from our analysis due to contamination by spectral line emission. For the UV/IR part of the synchrotron spectrum, we arrive at $\alpha _{\nu } = 0.87^{+0.08}_{-0.10}$. There is room for 2.5 × 10−3 M⊙ of dust with a temperature of ∼55 K if there are dual breaks in the synchrotron spectrum, one around ∼9 × 1010 Hz and another at ∼2 × 1013 Hz. The spectral index then changes at ∼9 × 1010 Hz from αν = 0.14 ± 0.07 in the radio to $\alpha _{\nu } = 0.35^{-0.07}_{+0.05}$ in the millimetre-to-far-IR range. The ACA Band 6 data marginally resolve the PWN. In particular, the strong emission $\text{$\sim$} 1\hbox{$.\!\!^{\prime \prime }$}5$ south-west of the pulsar, seen at other wavelengths, and resolved in the 3 cm data with its 0.″8 spatial resolution, is also strong in the millimetre range. The ACA data clearly reveal the supernova remnant shell ∼20–35 arcsec west of the pulsar, and for the shell we derive αν = 0.64 ± 0.05 for the range 8.6–145 GHz.
We present high spatial resolution optical imaging and polarization observations of the PSR B0540−69.3 and its highly dynamical pulsar wind nebula (PWN) performed with Hubble Space Telescope, and ...compare them with X-ray data obtained with the Chandra X-ray Observatory. In particular, we have studied the bright region south-west of the pulsar where a bright 'blob' is seen in 1999. In a recent paper by De Luca et al. it was argued that the 'blob' moves away from the pulsar at high speed. We show that it may instead be a result of local energy deposition around 1999, and that the emission from this then faded away rather than moved outward. Polarization data from 2007 show that the polarization properties show dramatic spatial variations at the 1999 blob position arguing for a local process. Several other positions along the pulsar-'blob' orientation show similar changes in polarization, indicating previous recent local energy depositions. In X-rays, the spectrum steepens away from the 'blob' position, faster orthogonal to the pulsar-'blob' direction than along this axis of orientation. This could indicate that the pulsar-'blob' orientation is an axis along where energy in the PWN is mainly injected, and that this is then mediated to the filaments in the PWN by shocks. We highlight this by constructing an S ii-to-O iii-ratio map, and comparing this to optical continuum and X-ray emission maps. We argue, through modelling, that the high S ii/O iii ratio is not due to time-dependent photoionization caused by possible rapid X-ray emission variations in the 'blob' region. We have also created a multiwavelength energy spectrum for the 'blob' position showing that one can, to within 2σ, connect the optical and X-ray emission by a single power law. The slope of that power law (defined from
) would be αν= 0.74 ± 0.03, which is marginally different from the X-ray spectral slope alone with αν= 0.65 ± 0.03. A single power law for most of the PWN is, however, not be possible. We obtain best power-law fits for the X-ray spectrum if we include 'extra' oxygen, in addition to the oxygen column density in the interstellar gas of the Large Magellanic Cloud and the Milky Way. This oxygen is most naturally explained by the oxygen-rich ejecta of the supernova remnant. The oxygen needed likely places the progenitor mass in the 20-25 M⊙ range, i.e. in the upper mass range for progenitors of Type IIP supernovae.
Recently, several genome-wide association studies (GWAS) have independently found numerous loci at which common single-nucleotide polymorphisms (SNPs) modestly influence the risk of developing ...colorectal cancer. The aim of this study was to test 11 loci, reported to be associated with an increased or decreased risk of colorectal cancer: 8q23.3 (rs16892766), 8q24.21 (rs6983267), 9p24 (rs719725), 10p14 (rs10795668), 11q23.1 (rs3802842), 14q22.2 (rs4444235), 15q13.3 (rs4779584), 16q22.1 (rs9929218), 18q21.1 (rs4939827), 19q13.1 (rs10411210) and 20p12.3 (rs961253), in a Swedish-based cohort.
The cohort was composed of 1786 cases and 1749 controls that were genotyped and analysed statistically. Genotype-phenotype analysis, for all 11 SNPs and sex, age of onset, family history of CRC and tumour location, was performed.
Of eleven loci, 5 showed statistically significant odds ratios similar to previously published findings: 8q23.3, 8q24.21, 10p14, 15q13.3 and 18q21.1. The remaining loci 11q23.1, 16q22.1, 19q13.1 and 20p12.3 showed weak trends but somehow similar to what was previously published. The loci 9p24 and 14q22.2 could not be confirmed. We show a higher number of risk alleles in affected individuals compared to controls. Four statistically significant genotype-phenotype associations were found; the G allele of rs6983267 was associated to older age, the G allele of rs1075668 was associated with a younger age and sporadic cases, and the T allele of rs10411210 was associated with younger age.
Our study, using a Swedish population, supports most genetic variants published in GWAS. More studies are needed to validate the genotype-phenotype correlations.
We present and discuss new visual wavelength-range observations of the inner regions of the supernova remnant SNR 0540−69.3 that is located in the Large Magellanic Cloud (LMC). These observations ...provide us with more spatial and spectral information than were previously available for this object. We use these data to create a detailed three-dimensional model of the remnant, assuming linear expansion of the ejecta. With the observations and the model, we study the general three-dimensional structure of the remnant, and the influence of an active region in the remnant - a 'blob' - that we address in previous papers. We used the fibre-fed integral-field Visual Multi-Object Spectrograph at the Very Large Telescope of the European Southern Observatory. The observations provide us with three-dimensional data in O iii λ5007 and S ii λλ6717, 6731 at a 0.33 arcsec × 0.33 arcsec spatial sampling and a velocity resolution of about 35 km s− 1. We decomposed the two, partially overlapping, sulphur lines and used them to calculate electron densities across the remnant at a high signal-to-noise ratio. In our study, we recover results of previous studies, but we are more importantly able to obtain more detailed information than before. Our analysis reveals a structure that stretches from the position of the 'blob', and into the plane of the sky at a position angle of PA 60°. Assuming a remnant age of 1000 yr and the usual LMC distance, the structure has an inclination angle of about 65° to the line of sight. The position angle is close to the symmetry axis with present and past activity in the visual and the X-ray wavelength ranges. We speculate that the pulsar is positioned along this activity axis, where it has a velocity along the line of sight of a few hundred km s− 1. The 'blob' is most likely a region of shock activity, as it is mainly bright in S ii; future observations of O ii λλ3726, 3729 would be useful to test whether the S/O abundance ratio is higher than average for that location in the remnant. The striking resemblance in X-rays between the pulsar wind nebula (PWN) of SNR 0540−69.3 and the Crab, in combination with our findings in this paper, suggests that the symmetry axis is part of a torus in the PWN. This is in agreement with the original suggestion by Gotthelf & Wang.
Background Erosive lichen planus is a severe, recurrent and recalcitrant disease that affects several mucosal areas, mostly the genital area and the mouth, but also, for example, the oesophagus and ...perianal area. The disease causes serious symptoms, because of the raw, de‐epithelialized mucosa and healing with scars/adhesions, which affect the patient's life in many ways. It causes, for example, difficulties in eating, drinking and going to the bathroom. Treatment is complicated and, so far, few therapeutic drugs other than steroids have been reported.
Objectives As the disease has severe implications on the patient's life it is important to investigate the psychological health of the patients, as well as the influence of stress on their health and wellbeing, in order to improve treatment.
Study design, subjects and methods Forty‐nine consecutive patients with erosive lichen planus were included during a 1‐year period. The study was carried out as ‘state‐of‐the‐last‐month’, and stress, state anxiety, depression and ‘erosive lichen planus factors’, i.e. symptoms affecting daily life, were assessed.
Results Eighty‐seven per cent of the patients had symptoms, severely affecting daily life. Unexpectedly, oral symptoms seemed to be the most prominent. Our results showed that depression, anxiety and stress were more common in patients with erosive lichen planus than in a control group.
Discussion and conclusions Erosive lichen planus is a severe disease with symptoms and complications affecting the patient's life. Our results indicate that their psychological health is also affected and emphasize the need for close collaboration between physicians, dentists with special knowledge in oral medicine and counsellors/psychologists to optimize handling of these patients.
ABSTRACT We present high spatial resolution optical imaging and polarization observations of the PSRB0540-69.3 and its highly dynamical pulsar wind nebula (PWN) performed with Hubble Space Telescope, ...and compare them with X-ray data obtained with the Chandra X-ray Observatory. In particular, we have studied the bright region south-west of the pulsar where a bright 'blob' is seen in 1999. In a recent paper by De Luca et al. it was argued that the 'blob' moves away from the pulsar at high speed. We show that it may instead be a result of local energy deposition around 1999, and that the emission from this then faded away rather than moved outward. Polarization data from 2007 show that the polarization properties show dramatic spatial variations at the 1999 blob position arguing for a local process. Several other positions along the pulsar-'blob' orientation show similar changes in polarization, indicating previous recent local energy depositions. In X-rays, the spectrum steepens away from the 'blob' position, faster orthogonal to the pulsar-'blob' direction than along this axis of orientation. This could indicate that the pulsar-'blob' orientation is an axis along where energy in the PWN is mainly injected, and that this is then mediated to the filaments in the PWN by shocks. We highlight this by constructing an Sii-to-Oiii-ratio map, and comparing this to optical continuum and X-ray emission maps. We argue, through modelling, that the high Sii/Oiii ratio is not due to time-dependent photoionization caused by possible rapid X-ray emission variations in the 'blob' region. We have also created a multiwavelength energy spectrum for the 'blob' position showing that one can, to within 2σ, connect the optical and X-ray emission by a single power law. The slope of that power law (defined from ) would be αν= 0.74 ± 0.03, which is marginally different from the X-ray spectral slope alone with αν= 0.65 ± 0.03. A single power law for most of the PWN is, however, not be possible. We obtain best power-law fits for the X-ray spectrum if we include 'extra' oxygen, in addition to the oxygen column density in the interstellar gas of the Large Magellanic Cloud and the Milky Way. This oxygen is most naturally explained by the oxygen-rich ejecta of the supernova remnant. The oxygen needed likely places the progenitor mass in the 20-25M range, i.e. in the upper mass range for progenitors of Type IIP supernovae. PUBLICATION ABSTRACT
We discuss high resolution VLT/UVES observations (FWHM ~ 6 km s-1) from October 2002 (day ~5700 past explosion) of the shock interaction of SN 1987A and its circumstellar ring. A large number of ...narrow emission lines from the unshocked ring, with ion stages from neutral up to Ne V and Fe VII, have been identified. A nebular analysis of the narrow lines from the unshocked gas indicates gas densities of (~1.5-5.0)$\times$103 cm-3 and temperatures of ~6.5$\times$103-2.4$\times$104 K. This is consistent with the thermal widths of the lines. From the shocked component we observe a large range of ionization stages from neutral lines to Fe XIV. From a nebular analysis we find that the density in the low ionization region is 4$\times$106-107 cm-3. There is a clear difference in the high velocity extension of the low ionization lines and that of lines from Fe X-XIV , with the latter extending up to ~-390 km s-1 in the blue wing for Fe XIV, while the low ionization lines extend to typically ~-260 km s-1. For Hα a faint extension up to ~-450 km s-1 can be seen probably arising from a small fraction of shocked high density clumps. We discuss these observations in the context of radiative shock models, which are qualitatively consistent with the observations. A fraction of the high ionization lines may originate in gas which has yet not had time to cool, explaining the difference in width between the low and high ionization lines. The maximum shock velocities seen in the optical lines are ~510 km s-1. We expect the maximum width of especially the low ionization lines to increase with time.
Context. The Crab-like supernova remnant 3C 58 contains the young pulsar PSR J0295+6449, which powers a radio plerion and a compact torus-like pulsar wind nebula visible in X-rays. Aims. We have ...performed deep optical imaging of the 3C 58 field to detect the optical counterpart of the pulsar and its wind nebula. Methods. The imaging was carried out with the Nordic Optical Telescope. We also analyzed the archival images of the field obtained with the Chandra/ACIS-S and HRC-S in X-rays and with the Spitzer/IRAC in the mid-infrared. Results. We detect a faint extended elliptical optical object with $B=24\fm06 \pm 0.08$ and $V=23\fm11 \pm 0.04$, whose center and peak brightness position are consistent at the sub-arcsecond level with the position of the pulsar. The morphology of the object and the orientation of its major axis are in excellent agreement with the torus region of the pulsar wind nebula seen almost edge on in the X-rays, although its extension is only about a half of what is in X-rays. This suggests that in the optical we see only the brightest central part of the torus nebula with the pulsar. The position and morphology of the object are also practically identical to the counterpart of the torus region recently detected in the mid-infrared bands. We do not resolve any point-like source within the nebula that could be identified with the pulsar and estimate that the contribution of the pulsar to the observed optical flux is $\la$10%. Using the archival Chandra/ACIS-S data we analyzed the spectrum of the pulsar+nebula X-ray emission extracted from the spatial region constrained by the optical/infrared source position and extent and find that a single absorbed power law provides an acceptable spectral fit. Combining this fit with the optical and infrared fluxes of the detected candidate torus nebula counterpart, we compile a tentative multi-wavelength spectrum of the central part of the pulsar nebula. Within the uncertainties of the interstellar extinction towards 3C 58, it is reminiscent of either the Crab or PSR B0540-69 pulsar wind nebula spectra. Conclusions. The position, morphology, and spectral properties of the detected source strongly suggest that it is the optical/mid-infrared counterpart of the 3C 58 pulsar + its wind nebula system. This makes 3C 58 the third member, together with the Crab and PSR B0540-69, of such a system as identified in the optical and mid-infrared.
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