21 research outputs found
The SuperWASP catalogue of 4963 RR Lyr stars: identification of 983 Blazhko candidates
Aims. We set out to compile a catalogue of RRab pulsating variables in the SuperWASP archive and identify candidate Blazhko effect objects within this catalogue. We analysed their light curves and power spectra for correlations in their common characteristics to further our understanding of the phenomenon. Methods. Pulsation periods were found for each SWASP RRab object using PDM techniques. Low frequency periodic signals detected
in the CLEAN power spectra of RRab stars were matched with modulation sidebands and combined with pairs of sidebands to produce a list of candidate Blazhko periods. A novel technique was used in an attempt to identify Blazhko effect stars by comparing scatter at different parts of the folded light curve. Pulsation amplitudes were calculated based on phase folded light curves.Results. The SuperWASP RRab catalogue consists of 4963 objects of which 3397 are previously unknown. We discovered 983 distinct candidates for Blazhko effect objects, 613 of these being previously unknown in the literature as RR Lyrae stars, and 894 are previously unknown to be Blazhko effect stars. Correlations were investigated between the scatter of points on the light curve, the periods and amplitudes of the objects’ pulsations, and those of the Blazhko effect.Conclusions. A statistical analysis has been performed on a large population of Blazhko effect stars from the wide-field SuperWASP survey. No correlations were found between the Blazhko period and other parameters including the Blazhko amplitude, although we confirmed a lower rate of occurrence of the Blazhko effect in long pulsation period objects
Legislation of direct-to-consumer genetic testing in Europe: a fragmented regulatory landscape
Despite the increasing availability of direct-to-consumer (DTC) genetic testing, it is currently unclear how such services are regulated in Europe, due to the lack of EU or national legislation specifically addressing this issue. In this article, we provide an overview of laws that could potentially impact the regulation of DTC genetic testing in 26 European countries, namely Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, the Netherlands and the United Kingdom. Emphasis is placed on provisions relating to medical supervision, genetic counselling and informed consent. Our results indicate that currently there is a wide spectrum of laws regarding genetic testing in Europe. There are countries (e.g. France and Germany) which essentially ban DTC genetic testing, while in others (e.g. Luxembourg and Poland) DTC genetic testing may only be restricted by general laws, usually regarding health care services and patients’ rights
Recommended from our members
Erratum: "On the Use of Field RR Lyrae as Galactic Probes. V. Optical and Radial Velocity Curve Templates" (2021, ApJ, 919, 85)
[no abstract available
On the Use of Field RR Lyrae as Galactic Probes. V. Optical and radial velocity curve templates
We collected the largest spectroscopic catalog of RR Lyrae (RRLs) including
20,000 high-, medium- and low-resolution spectra for 10,000
RRLs. We provide the analytical forms of radial velocity curve (RVC) templates.
These were built using 36 RRLs (31 fundamental -- split into three period bins
-- and 5 first overtone pulsators) with well-sampled RVCs based on three groups
of metallic lines (Fe, Mg, Na) and four Balmer lines (H, H,
H, H).
We tackled the long-standing problem of the reference epoch to anchor light
curve and RVC templates. For the -band, we found that the residuals of the
templates anchored to the phase of the mean magnitude along the rising branch
are 35\% to 45\% smaller than those anchored to the phase of
maximum light. For the RVC, we used two independent reference epochs for
metallic and Balmer lines and we verified that the residuals of the RVC
templates anchored to the phase of mean RV are from 30\% (metallic lines) up to
45\% (Balmer lines) smaller than those anchored to the phase of minimum RV.
We validated our RVC templates by using both the single- and the three-phase
points approach. We found that barycentric velocities based on our RVC
templates are two-three times more accurate than those available in the
literature. We applied the current RVC templates to Balmer lines RVs of RRLs in
the globular NGC~3201 collected with MUSE at VLT. We found the cluster
barycentric RV of =496.898.37(error)3.43 (standard
deviation) km/s, which agrees well with literature estimates
First Results on RR Lyrae Stars with the TESS Space Telescope: Untangling the Connections between Mode Content, Colors, and Distances
Abstract
The Transiting Exoplanet Survey Satellite (TESS) space telescope is collecting continuous, high-precision optical photometry of stars throughout the sky, including thousands of RR Lyrae stars. In this paper, we present results for an initial sample of 118 nearby RR Lyrae stars observed in TESS Sectors 1 and 2. We use differential image photometry to generate light curves and analyze their mode content and modulation properties. We combine accurate light-curve parameters from TESS with parallax and color information from the Gaia mission to create a comprehensive classification scheme. We build a clean sample, preserving RR Lyrae stars with unusual light-curve shapes, while separating other types of pulsating stars. We find that a large fraction of RR Lyrae stars exhibit various low-amplitude modes, but the distribution of those modes is markedly different from those of the bulge stars. This suggests that differences in physical parameters have an observable effect on the excitation of extra modes, potentially offering a way to uncover the origins of these signals. However, mode identification is hindered by uncertainties when identifying the true pulsation frequencies of the extra modes. We compare mode amplitude ratios in classical double-mode stars to stars with extra modes at low amplitudes and find that they separate into two distinct groups. Finally, we find a high percentage of modulated stars among the fundamental mode pulsators, but also find that at least 28% of them do not exhibit modulation, confirming that a significant fraction of stars lack the Blazhko effect.</jats:p
On the Use of Field RR Lyrae as Galactic Probes. V. Optical and Radial Velocity Curve Templates
We collected the largest spectroscopic catalog of RR Lyrae (RRLs) including ≈20,000 high-, medium-, and low-resolution spectra for ≈10,000 RRLs. We provide the analytical forms of radial velocity curve (RVC) templates. These were built using 36 RRLs (31 fundamental—split into three period bins—and five first-overtone pulsators) with well-sampled RVCs based on three groups of metallic lines (Fe, Mg, Na) and four Balmer lines (Hα, Hβ, Hγ, Hδ). We tackled the long-standing problem of the reference epoch to anchor light-curve and RVC templates. For the V-band, we found that the residuals of the templates anchored to the phase of the mean magnitude along the rising branch are ∼35% to ∼45% smaller than those anchored to the phase of maximum light. For the RVC, we used two independent reference epochs for metallic and Balmer lines and we verified that the residuals of the RVC templates anchored to the phase of mean RV are from 30% (metallic lines) up to 45% (Balmer lines) smaller than those anchored to the phase of minimum RV. We validated our RVC templates by using both the single-point and the three phase point approaches. We found that barycentric velocities based on our RVC templates are two to three times more accurate than those available in the literature. We applied the current RVC templates to Balmer lines RVs of RRLs in the globular NGC 3201 collected with MUSE at VLT. We found the cluster barycentric RV of Vγ = 496.89 ± 8.37(error) ± 3.43 (standard deviation) km s−1, which agrees well with literature estimates
Legislation of direct-to-consumer genetic testing in Europe: a fragmented regulatory landscape
Despite the increasing availability of direct-to-consumer (DTC) genetic testing, it is currently unclear how such services are regulated in Europe, due to the lack of EU or national legislation specifically addressing this issue. In this article, we provide an overview of laws that could potentially impact the regulation of DTC genetic testing in 26 European countries, namely Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, the Netherlands and the United Kingdom. Emphasis is placed on provisions relating to medical supervision, genetic counselling and informed consent. Our results indicate that currently there is a wide spectrum of laws regarding genetic testing in Europe. There are countries (e.g. France and Germany) which essentially ban DTC genetic testing, while in others (e.g. Luxembourg and Poland) DTC genetic testing may only be restricted by general laws, usually regarding health care services and patients' rights.status: publishe