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1.	Gould, A., et al. (author) MOA-2010-BLG-523:" Failed Planet"= RS CVn Star 2013 In: Astrophysical Journal. - 0004-637X. ; 763:2 Journal article (peer-reviewed)abstract The Galactic bulge source MOA-2010-BLG-523S exhibited short-term deviations from a standard microlensing light curve near the peak of an A(max) similar to 265 high-magnification microlensing event. The deviations originally seemed consistent with expectations for a planetary companion to the principal lens. We combine long-term photometric monitoring with a previously published high-resolution spectrum taken near peak to demonstrate that this is an RS CVn variable, so that planetary microlensing is not required to explain the light-curve deviations. This is the first spectroscopically confirmed RS CVn star discovered in the Galactic bulge.
2.	Ryu, Y. -H., et al. (author) OGLE-2016-BLG-1190Lb : The First Spitzer Bulge Planet Lies Near the Planet/Brown-dwarf Boundary 2018 In: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 155:1 Journal article (peer-reviewed)abstract We report the discovery of OGLE-2016-BLG-1190Lb, which is likely to be the first Spitzer microlensing planet in the Galactic bulge/ bar, an assignation that can be confirmed by two epochs of high-resolution imaging of the combined source-lens baseline object. The planet's mass, M-p = 13.4 +/- 0.9 M-J, places it right at the deuteriumburning limit, i. e., the conventional boundary between planets and brown dwarfs. Its existence raises the question of whether such objects are really planets (formed within the disks of their hosts) or failed stars (lowmass objects formed by gas fragmentation). This question may ultimately be addressed by comparing disk and bulge/bar planets, which is a goal of the Spitzer microlens program. The host is a G dwarf, M-host = 0.89. +/- 0.07 M-circle dot, and the planet has a semimajor axis a similar to 2.0 au. We use Kepler K2 Campaign 9 microlensing data to break the lens-mass degeneracy that generically impacts parallax solutions from Earth-Spitzer observations alone, which is the first successful application of this approach. The microlensing data, derived primarily from near-continuous, ultradense survey observations from OGLE, MOA, and three KMTNet telescopes, contain more orbital information than for any previous microlensing planet, but not quite enough to accurately specify the full orbit. However, these data do permit the first rigorous test of microlensing orbital-motion measurements, which are typically derived from data taken over < 1% of an orbital period.
3.	Osborn, H. P., et al. (author) The PDS 110 observing campaign - photometric and spectroscopic observations reveal eclipses are aperiodic 2019 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 485:2, s. 1614-1625 Journal article (peer-reviewed)abstract PDS 110 is a young disc-hosting star in the Orion OB1A association. Two dimming events of similar depth and duration were seen in 2008 (WASP) and 2011 (KELT), consistent with an object in a closed periodic orbit. In this paper, we present data from a ground-based observing campaign designed to measure the star both photometrically and spectroscopically during the time of predicted eclipse in 2017 September. Despite high-quality photometry, the predicted eclipse did not occur, although coherent structure is present suggesting variable amounts of stellar flux or dust obscuration. We also searched for radial velocity (RV) oscillations caused by any hypothetical companion and can rule out close binaries to 0.1Ms. Asearch of Sonneberg plate archive data also enabled us to extend the photometric baseline of this star back more than 50 yr, and similarly does not re-detect any deep eclipses. Taken together, they suggest that the eclipses seen in WASP and KELT photometry were due to aperiodic events. It would seem that PDS 110 undergoes stochastic dimmings that are shallower and of shorter duration than those of UX Ori variables, but may have a similar mechanism.
4.	Udalski, A., et al. (author) OGLE-2017-BLG-1434Lb : Eighth q < 1 x 10(-4) Mass-Ratio Microlens Planet Confirms Turnover in Planet Mass-Ratio Function 2018 In: Acta Astronomica. - 0001-5237. ; 68:1, s. 1-42 Journal article (peer-reviewed)abstract We report the discovery of a cold Super-Earth planet (m(p) = 4.4 +/- 0.5 M-circle plus) orbiting a low-mass (M = 0.23 +/- 0.03 M-circle dot) M dwarf at projected separation a(perpendicular to) l = 1.18 +/- 0.10 a.u., i.e., about 1.9 times the distance the snow line. The system is quite nearby for a microlensing planet, D-L = 0.86 +/- 0.09 kpc. Indeed, it was the large lens-source relative parallax pi(rel) = 1.0 mas (combined with the low mass M) that gave rise to the large, and thus well-measured, microlens parallax pi(E) proportional to (pi(rel)/M)(1)(/2) that enabled these precise measurements. OGLE-2017-BLG-1434Lb is the eighth microlensing planet with planet-host mass ratio q < 1 x 10(-4). We apply a new planet-detection sensitivity method, which is a variant of V/V-max, to seven of these eight planets to derive the mass-ratio function in this regime. We find dN/ d lnq proportional to q(P) , with p =1.05(-0.68)(+0.78), which confirms the turnover in the mass function found by Suzuki et al. relative to the power law of opposite sign n = -0.93 +/- 0.13 at higher mass ratios q greater than or similar to 2 x 10(-4). We combine our result with that of Suzuki et al. to obtain p = 0.73(-0.34)(+0.42.)
5.	Hirao, Yuki, et al. (author) OGLE-2017-BLG-0406 : Spitzer Microlens Parallax Reveals Saturn-mass Planet Orbiting M-dwarf Host in the Inner Galactic Disk 2020 In: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 160:2 Journal article (peer-reviewed)abstract We report the discovery and analysis of the planetary microlensing event OGLE-2017-BLG-0406, which was observed both from the ground and by the Spitzer satellite in a solar orbit. At high magnification, the anomaly in the light curve was densely observed by ground-based-survey and follow-up groups, and it was found to be explained by a planetary lens with a planet/host mass ratio of q = 7.0 x 10(-4) from the light-curve modeling. The ground-only and Spitzer-only data each provide very strong one-dimensional (1D) constraints on the 2D microlens parallax vector pi(E). When combined, these yield a precise measurement of pi(E) and of the masses of the host M-host = 0.56 +/- 0.07 M-circle dot and planet M-planet = 0.41 +/- 0.05 M-Jup. The system lies at a distance D-L = 5.2 +/- 0.5 kpc from the Sun toward the Galactic bulge, and the host is more likely to be a disk population star according to the kinematics of the lens. The projected separation of the planet from the host is a(perpendicular to) = 3.5 +/- 0.3 au (i.e., just over twice the snow line). The Galactic-disk kinematics are established in part from a precise measurement of the source proper motion based on OGLE-IV data. By contrast, the Gaia proper-motion measurement of the source suffers from a catastrophic 10 sigma error.
6.	Maxted, P. F. L., et al. (author) Fundamental effective temperature measurements for eclipsing binary stars - III. SPIRou near-infrared spectroscopy and CHEOPS photometry of the benchmark G0V star EBLM J0113+31 2022 In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 513:4, s. 6042-6057 Journal article (peer-reviewed)abstract EBLM J0113+31 is a moderately bright (V = 10.1), metal-poor ([Fe/H] approximate to-0.3) GOV star with a much fainter M dwarf companion on a wide, eccentric orbit (= 14.3 d). We have used near-infrared spectroscopy obtained with the SPIRou spectrograph to measure the semi-amplitude of the M dwarf's spectroscopic orbit, and high-precision photometry of the eclipse and transit from the CHEOPS and TESS space missions to measure the geometry of this binary system. From the combined analysis of these data together with previously published observations, we obtain the following model-independent masses and radii: M-1 = 1.029 +/- 0.025 M-circle dot, M-2 = 0.197 +/- 0.003 M-circle dot, R-1 = 1.417 +/- 0.014 R-circle dot, R-2 = 0.215 +/- 0.002 R-circle dot. Using R-1 and the parallax from Gaia EDR3 we find that this star's angular diameter is theta = 0.0745 +/- 0.0007 mas. The apparent bolometric flux of the GOV star corrected for both extinction and the contribution from the M dwarf (<0.2 per cent) is F-circle plus,F-0 = (2.62 +/- 0.05) x 10(-9) erg cm(-2) S-1. Hence, this G0V star has an effective temperature T-eff(,1) = 6124 K +/- 40 K (rnd.) +/- 10 K (sys.). EBLM J0113+31 is an ideal benchmark star that can be used for 'end-to-end' tests of the stellar parameters measured by large-scale spectroscopic surveys, or stellar parameters derived from asteroseismology with PLATO. The techniques developed here can be applied to many other eclipsing binaries in order to create a network of such benchmark stars.
7.	Jaimes, R. Figuera, et al. (author) Many new variable stars discovered in the core of the globular cluster NGC 6715 (M54) with EMCCD observations 2016 In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 592 Journal article (peer-reviewed)abstract Context. We show the benefits of using electron-multiplying CCDs and the shift-and-add technique as a tool to minimise the effects of atmospheric turbulence, such as blending between stars in crowded fields, and to avoid saturated stars in the fields observed. We intend to complete, or improve on, the census of the variable star population in globular cluster NGC 6715. Aims. Our aim is to obtain high-precision time-series photometry of the very crowded central region of this stellar system via the collection of better angular resolution images than has been previously achieved with conventional CCDs on ground-based telescopes. Methods. Observations were carried out using the Danish 1.54-m telescope at the ESO La Silla observatory in Chile. The telescope is equipped with an electron-multiplying CCD that enables short-exposure-time images to be obtained (ten images per second) that were stacked using the shift-and-add technique to produce the normal-exposure-time images (minutes). The high precision photometry was performed via difference image analysis employing the DanDIA pipeline. We attempted automatic detection of variable stars in the field. Results. We statistically analysed the light curves of 1405 stars in the crowded central region of NGC 6715 to automatically identify the variable stars present in this cluster. We found light curves for 17 previously known variable stars near the edges of our reference image (16 RR Lyrae and 1 semi-regular) and we discovered 67 new variables (30 RR Lyrae, 21 irregular (long-period type), 3 semi-regular, 1 W Virginis, 1 eclipsing binary, and 11 unclassified). Photometric measurements for these stars are available in electronic form through the Strasbourg Astronomical Data Centre.
8.	Swayne, M.I., et al. (author) The EBLM Project– XI. Mass, radius, and effective temperature measurements for 23 M-dwarf companions to solar-type stars observed with CHEOPS 2024 In: Monthly Notices of the Royal Astronomical Society. - 0035-8711 .- 1365-2966. ; 528:4, s. 5703-5722 Journal article (peer-reviewed)abstract Observations of low-mass stars have frequently shown a disagreement between observed stellar radii and radii predicted by theoretical stellar structure models. This ‘radius inflation’ problem could have an impact on both stellar and exoplanetary science. We present the final results of our observation programme with the CHaracterising ExOPlanet Satellite (CHEOPS) to obtain high-precision light curves of eclipsing binaries with low-mass stellar companions (EBLMs). Combined with the spectroscopic orbits of the solar-type companions, we can derive the masses, radii, and effective temperatures of 23 M-dwarf stars. We use the PYCHEOPS data analysis software to analyse their primary and secondary occultations. For all but one target, we also perform analyses with Transiting Exoplanet Survey Satellite (TESS) light curves for comparison. We have assessed the impact of starspot-induced variation on our derived parameters and account for this in our radius and effective temperature uncertainties using simulated light curves. We observe trends in inflation with both metallicity and orbital separation. We also observe a strong trend in the difference between theoretical and observational effective temperatures with metallicity. There is no such trend with orbital separation. These results are not consistent with the idea that the observed inflation in stellar radius combines with lower effective temperature to preserve the luminosity predicted by low-mass stellar models. Our EBLM systems provide high-quality and homogeneous measurements that can be used in further studies of radius inflation.
9.	Mancini, L., et al. (author) Physical properties and transmission spectrum of the WASP-74 planetary system from multiband photometry 2019 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 485:4, s. 5168-5179 Journal article (peer-reviewed)abstract We present broad-band photometry of 11 planetary transits of the hot Jupiter WASP-74 b, using three medium-class telescopes and employing the telescope-defocusing technique. Most of the transits were monitored through I filters and one was simultaneously observed in five optical (U, g', r', i', z') and three near-infrared (J, H, K) passbands, for a total of 18 light curves. We also obtained new high-resolution spectra of the host star. We used these new data to review the orbital and physical properties of the WASP-74 planetary system. We were able to better constrain the main system characteristics, measuring smaller radius and mass for both the hot Jupiter and its host star than previously reported in the literature. Joining our optical data with those taken with the HST in the near infrared, we built up an observational transmission spectrum of the planet, which suggests the presence of strong optical absorbers, as TiO and VO gases, in its atmosphere.
10.	Alexoudi, X., et al. (author) Deciphering the atmosphere of HAT-P-12b : solving discrepant results 2018 In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 620 Journal article (peer-reviewed)abstract Context. Two independent investigations of the atmosphere of the hot Jupiter HAT-P-12b by two different groups resulted in discrepant solutions. Using broad-band photometry from the ground, one study found a flat and featureless transmission spectrum that was interpreted as gray absorption by dense cloud coverage. The second study made use of Hubble Space Telescope (HST) observations and found Rayleigh scattering at optical wavelengths caused by haze. Aims. The main purpose of this work is to determine the source of this inconsistency and provide feedback to prevent similar discrepancies in future analyses of other exoplanetary atmospheres. Methods. We studied the observed discrepancy via two methods. With further broad-band observations in the optical wavelength regions, we strengthened the previous measurements in precision, and with a homogeneous reanalysis of the published data, we were able to assess the systematic errors and the independent analyses of the two different groups. Results. Repeating the analysis steps of both works, we found that deviating values for the orbital parameters are the reason for the aforementioned discrepancy. Our work showed a degeneracy of the planetary spectral slope with these parameters. In a homogeneous reanalysis of all data, the two literature data sets and the new observations converge to a consistent transmission spectrum, showing a low-amplitude spectral slope and a tentative detection of potassium absorption.
11.	Bolin, Bryce T., et al. (author) The discovery and characterization of (594913) 'Ayló'chaxnim, a kilometre sized asteroid inside the orbit of Venus 2022 In: Monthly notices of the Royal Astronomical Society. Letters. - : Oxford University Press. - 1745-3925 .- 1745-3933. ; 517:1, s. L49-L54 Journal article (peer-reviewed)abstract Near-Earth asteroid population models predict the existence of bodies located inside the orbit of Venus. Despite searches up to the end of 2019, none had been found. We report discovery and follow-up observations of (594913) 'Ayló'chaxnim, an asteroid with an orbit entirely interior to Venus. (594913) 'Ayló'chaxnim has an aphelion distance of ∼0.65 au, is ∼2 km in diameter and is red in colour. The detection of such a large asteroid inside the orbit of Venus is surprising given their rarity according to near-Earth asteroid population models. As the first officially numbered and named asteroid located entirely within the orbit of Venus, we propose that the class of interior to Venus asteroids be referred to as 'Ayló'chaxnim asteroids.
12.	Ho, Phay J., et al. (author) The role of transient resonances for ultra-fast imaging of single sucrose nanoclusters 2020 In: Nature Communications. - : NATURE PUBLISHING GROUP. - 2041-1723. ; 11 Journal article (peer-reviewed)abstract Intense x-ray free-electron laser (XFEL) pulses hold great promise for imaging function in nanoscale and biological systems with atomic resolution. So far, however, the spatial resolution obtained from single shot experiments lags averaging static experiments. Here we report on a combined computational and experimental study about ultrafast diffractive imaging of sucrose clusters which are benchmark organic samples. Our theoretical model matches the experimental data from the water window to the keV x-ray regime. The large-scale dynamic scattering calculations reveal that transient phenomena driven by non-linear x-ray interaction are decisive for ultrafast imaging applications. Our study illuminates the complex interplay of the imaging process with the rapidly changing transient electronic structures in XFEL experiments and shows how computational models allow optimization of the parameters for ultrafast imaging experiments. X-ray free electron lasers provide high photon flux to explore single particle diffraction imaging of biological samples. Here the authors present dynamic electronic structure calculations and benchmark them to single-particle XFEL diffraction data of sucrose clusters to predict optimal single-shot imaging conditions.
13.	Kjellsson, Ludvig, et al. (author) Resonant Inelastic X-Ray Scattering Reveals Hidden Local Transitions of the Aqueous OH Radical 2020 In: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 124:23 Journal article (peer-reviewed)abstract Resonant inelastic x-ray scattering (RIXS) provides remarkable opportunities to interrogate ultra-fast dynamics in liquids. Here we use RIXS to study the fundamentally and practically important hydroxyl radical in liquid water, OH(aq). Impulsive ionization of pure liquid water produced a short-lived population of OH(aq), which was probed using femtosecond x-rays from an x-ray free-electron laser. We find that RIXS reveals localized electronic transitions that are masked in the ultraviolet absorption spectrum by strong charge-transfer transitions-thus providing a means to investigate the evolving electronic structure and reactivity of the hydroxyl radical in aqueous and heterogeneous environments. First-principles calculations provide interpretation of the main spectral features.
14.	Loh, Z-H, et al. (author) Observation of the fastest chemical processes in the radiolysis of water 2020 In: Science. - : AMER ASSOC ADVANCEMENT SCIENCE. - 0036-8075 .- 1095-9203. ; 367:6474, s. 179-182 Journal article (peer-reviewed)abstract Elementary processes associated with ionization of liquid water provide a framework for understanding radiation-matter interactions in chemistry and biology. Although numerous studies have been conducted on the dynamics of the hydrated electron, its partner arising from ionization of liquid water, H2O+, remains elusive. We used tunable femtosecond soft x-ray pulses from an x-ray free electron laser to reveal the dynamics of the valence hole created by strong-field ionization and to track the primary proton transfer reaction giving rise to the formation of OH. The isolated resonance associated with the valence hole (H2O+/OH) enabled straightforward detection. Molecular dynamics simulations revealed that the x-ray spectra are sensitive to structural dynamics at the ionization site. We found signatures of hydrated-electron dynamics in the x-ray spectrum.
15.	Mancini, L., et al. (author) The GAPS programme with HARPS-N at TNG XVI. Measurement of the Rossiter-McLaughlin effect of transiting planetary systems HAT-P-3, HAT-P-12, HAT-P-22, WASP-39, and WASP-60 2018 In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 613 Journal article (peer-reviewed)abstract Context. The measurement of the orbital obliquity of hot Jupiters with different physical characteristics can provide clues to the mechanisms of migration and orbital evolution of this particular class of giant exoplanets.Aims. We aim to derive the degree of alignment between planetary orbit and stellar spin angular momentum vectors and look for possible links with other orbital and fundamental physical parameters of the star-planet system. We focus on the characterisation of five transiting planetary systems (HAT-P-3, HAT-P-12, HAT-P-22, WASP-39, and WASP-60) and the determination of their sky-projected planet orbital obliquity through the measurement of the Rossiter-McLaughlin effect.Methods. We used HARPS-N high-precision radial velocity measurements, gathered during transit events, to measure the Rossiter-McLaughlin effect in the target systems and determine the sky-projected angle between the planetary orbital plane and stellar equator. The characterisation of stellar atmospheric parameters was performed by exploiting the HARPS-N spectra, using line equivalent width ratios and spectral synthesis methods. Photometric parameters of the five transiting exoplanets were re-analysed through 17 new light curves, obtained with an array of medium-class telescopes, and other light curves from the literature. Survey-time-series photometric data were analysed for determining the rotation periods of the five stars and their spin inclination.Results. From the analysis of the Rossiter-McLaughlin effect we derived a sky-projected obliquity of lambda = 21.2 degrees +/- 8.7 degrees, lambda = -54 degrees(+41 degrees)(-13 degrees), lambda = -2.1 degrees +/- 3.0 degrees, lambda = 0 degrees +/- 11 degrees, and lambda = -129 degrees +/- 17 degrees for HAT-P-3 b, HAT-P-12 b, HAT-P-22 b, WASP-39 b, and WASP-60 b, respectively. The latter value indicates that WASP-60 b is moving on a retrograde orbit. These values represent the first measurements of lambda for the five exoplanetary systems under study. The stellar activity of HAT-P-22 indicates a rotation period of 28.7 +/- 0.4 days, which allowed us to estimate the true misalignment angle of HAT-P-22 b, psi = 24 degrees +/- 18 degrees. The revision of the physical parameters of the five exoplanetary systems returned values that are fully compatible with those existing in the literature. The exception to this is the WASP-60 system, for which, based on higher quality spectroscopic and photometric data, we found a more massive and younger star and a larger and hotter planet.
16.	Milne, Christopher J., et al. (author) Disentangling the evolution of electrons and holes in photoexcited ZnO nanoparticles 2023 In: Structural Dynamics. - : American Institute of Physics (AIP). - 2329-7778. ; 10:6 Journal article (peer-reviewed)abstract The evolution of charge carriers in photoexcited room temperature ZnO nanoparticles in solution is investigated using ultrafast ultraviolet photoluminescence spectroscopy, ultrafast Zn K-edge absorption spectroscopy, and ab initio molecular dynamics (MD) simulations. The photoluminescence is excited at 4.66 eV, well above the band edge, and shows that electron cooling in the conduction band and exciton formation occur in <500 fs, in excellent agreement with theoretical predictions. The x-ray absorption measurements, obtained upon excitation close to the band edge at 3.49 eV, are sensitive to the migration and trapping of holes. They reveal that the 2 ps transient largely reproduces the previously reported transient obtained at 100 ps time delay in synchrotron studies. In addition, the x-ray absorption signal is found to rise in similar to 1.4 ps, which we attribute to the diffusion of holes through the lattice prior to their trapping at singly charged oxygen vacancies. Indeed, the MD simulations show that impulsive trapping of holes induces an ultrafast expansion of the cage of Zn atoms in <200 fs, followed by an oscillatory response at a frequency of similar to 100 cm-1, which corresponds to a phonon mode of the system involving the Zn sub-lattice.
17.	Tregloan-Reed, J., et al. (author) Possible detection of a bimodal cloud distribution in the atmosphere of HAT-P-32Ab from multiband photometry 2018 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 474:4, s. 5485-5499 Journal article (peer-reviewed)abstract We present high-precision photometry of eight separate transit events in the HAT-P-32 planetary system. One transit event was observed simultaneously by two telescopes of which one obtained a simultaneous multiband light curve in three optical bands, giving a total of 11 transit light curves. Due to the filter selection and in conjunction with using the defocused photometry technique, we were able to obtain an extremely high-precision, ground-based transit in the u band (350 nm), with an rms scatter of approximate to 1 mmag. All 11 transits were modelled using PRISM and GEMC, and the physical properties of the system calculated. We find the mass and radius of the host star to be 1.182 +/- 0.041 M-circle dot and 1.225 +/- 0.015 R-circle dot, respectively. For the planet, we find a mass of 0.80 +/- 0.14 M-Jup, a radius of 1.807 +/- 0.022 R-Jup, and a density of 0.126 +/- 0.023 rho(Jup). These values are consistent with those found in the literature. We also obtain a new orbital ephemeris for the system T-0 = BJD/TDB 2 454 420.447187(96)+2.15000800(10) x E. We measured the transmission spectrum of HAT-P-32Ab and compared it to theoretical transmission spectra. Our results indicate a bimodal cloud particle distribution consisting of Rayleigh-like haze and grey absorbing cloud particles within the atmosphere of HAT-P-32Ab.
18.	Haldrup, K., et al. (author) Guest-Host Interactions Investigated by Time-Resolved X-ray Spectroscopies and Scattering at MHz Rates: Solvation Dynamics and Photoinduced Spin Transition in Aqueous Fe(bipy)(3)(2+) 2012 In: The Journal of Physical Chemistry Part A: Molecules, Spectroscopy, Kinetics, Environment and General Theory. - : American Chemical Society (ACS). - 1520-5215. ; 116:40, s. 9878-9887 Journal article (peer-reviewed)abstract We have studied the photoinduced low spin (LS) to high spin (HS) conversion of [Fe(bipy)(3)](2+) in aqueous solution. In a laser pump/X-ray probe synchrotron setup permitting simultaneous, time-resolved X-ray diffuse scattering (XDS) and X-ray spectroscopic measurements at a 3.26 MHz repetition rate, we observed the interplay between intramolecular dynamics and the intermolecular caging solvent response with better than 100 ps time resolution. On this time scale, the initial ultrafast spin transition and the associated intramolecular geometric structure changes are long completed, as is the solvent heating due to the initial energy dissipation from the excited HS molecule. Combining information from X-ray emission spectroscopy and scattering, the excitation fraction as well as the temperature and density changes of the solvent can be closely followed on the subnanosecond time scale of the HS lifetime, allowing the detection of an ultrafast change in bulk solvent density. An analysis approach directly utilizing the spectroscopic data in the XDS analysis effectively reduces the number of free parameters, and both combined permit extraction of information about the ultrafast structural dynamics of the caging solvent, in particular, a decrease in the number of water molecules in the first solvation shell is inferred, as predicted by recent theoretical work.
19.	Hey, Daniel R., et al. (author) Parameters of the eclipsing binary alpha Draconis observed by TESS and SONG 2022 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 511:2, s. 2648-2658 Journal article (peer-reviewed)abstract We present an analysis of the eclipsing single-lined spectroscopic binary system a Dra based on photometry from the Transiting Exoplanet Survey Satellite (TESS) mission and newly acquired spectroscopic measurements. Recently discovered to have eclipses in the TESS data, at a magnitude of V = 3.7, alpha Dra is now one of the brightest detached eclipsing binary (EB) systems known. We obtain the parameters of this system by simultaneously fitting the TESS light curve in conjunction with radial velocities (RVs) acquired from the SONG spectrograph. We determine the fractional radii (Rla) for the primary and secondary components of the system to be 0.0479 +/- 0.0003 and 0.0226 +/- 0.0005, respectively. We constrain the temperature, mass, and luminosity (log(L/L-circle dot)) of the primary to be 9975 +/- 125 K, 3.7 +/- 0.1 M-circle dot, and 2.49 +/- 0.02, respectively, using isochrone fitting. Although the secondary is too faint to appear in the spectra, the obtained mass function and observed inclination yields a secondary minimum mass of M-2 = 2.5 +/- 0.1 M-circle dot, which suggests that it is an A2V type star. We were unable to obtain RVs of the secondary, and are only able to see a weak highly rotationally broadened absorption line, indicating that the secondary is rapidly rotating (vsin i similar to 200 km s(-1)). We also perform an abundance analysis of the primary star for 21 chemical elements. We find a complex abundance pattern, with a few elements having mild underabundances while the majority have solar abundances. We make available the PYTHON code used in this paper to facilitate future modelling of EBs. https://github.com/danhey/adra
20.	Li, S., et al. (author) Manifestation of postcollision interaction in Krypton LMN Auger spectra following K-shell photoionization 2022 In: Physical Review A: covering atomic, molecular, and optical physics and quantum information. - : American Physical Society. - 2469-9926 .- 2469-9934. ; 106:2 Journal article (peer-reviewed)abstract We report on an experimental and theoretical study of postcollision interaction (PCI) effects on L-2 - M4,5N2,3 Auger electrons measured above the Kr K-edge in which L-2 vacancies are primarily generated by KL2 x-ray emission. Such cascade processes, in which a deep inner-shell vacancy decays first by x-ray emission followed by Auger electron emission, is a strong decay mode in heavy atoms. The L-2 - M4,5N2,3 Auger electron peak is observed to become increasingly asymmetric with a shifting peak maximum as the absorbed x-ray energy approaches the K-shell ionization threshold. This is attributed to PCI energy exchanges of the Auger electron with the 1s photoelectron. To model the PCI effects, we have applied a semiclassical approach modified to account for the combined lifetimes of the K and L-2 hole states. In addition, our analysis treats several closely spaced Auger transitions with final ionic states having different terms and angular momenta.
21.	Mancini, L., et al. (author) An optical transmission spectrum of the transiting hot Jupiter in the metal-poor WASP-98 planetary system 2016 In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 461:1, s. 1053-1061 Journal article (peer-reviewed)abstract The WASP-98 planetary system represents a rare case of a hot Jupiter hosted by a metalpoor main-sequence star. We present a follow-up study of this system based on multiband photometry and high-resolution spectroscopy. Two new transit events of WASP-98 b were simultaneously observed in four passbands (g', r', i', z'), using the telescope-defocusing technique, yielding eight high-precision light curves with point-to-point scatters of less than 1 mmag. We also collected three spectra of the parent star with a high-resolution spectrograph, which we used to remeasure its spectral characteristics, in particular its metallicity. We found this to be very low, [Fe/ H] = -0.49 +/- 0.10, but larger than was previously reported, [Fe/ H]=-0.60 +/- 0.19. We used these new photometric and spectroscopic data to refine the orbital and physical properties of this planetary system, finding that the stellar and planetary mass measurements are significantly larger than those in the discovery paper. In addition, the multiband light curves were used to construct an optical transmission spectrum of WASP-98 b and probe the characteristics of its atmosphere at the terminator. We measured a lower radius at z' compared with the other three passbands. The maximum variation is between the r' and z' bands, has a confidence level of roughly 6 sigma and equates to 5.5 pressure scale heights. We compared this spectrum to theoretical models, investigating several possible types of atmospheres, including hazy, cloudy, cloud-free, and clear atmospheres with titanium and vanadium oxide opacities. We could not find a good fit to the observations, except in the extreme case of a clear atmosphere with TiO and VO opacities, in which the condensation of Ti and V was suppressed. As this case is unrealistic, our results suggest the presence of an additional optical-absorbing species in the atmosphere of WASP-98 b, of unknown chemical nature.
22.	Olsson, Anders, 1940-, et al. (author) Effects of rosuvastatin and atorvastatin compared over 52 weeks of treatment in patients with hypercholesterolemia 2002 In: American Heart Journal. - : Elsevier BV. - 0002-8703 .- 1097-6744. ; 144:6, s. 1044-1051 Journal article (peer-reviewed)abstract Background: Despite the demonstrated benefits of low-density lipoprotein cholesterol (LDL-C) reduction in reducing the risk of coronary heart disease, many patients receiving lipid-lowering therapy fail to achieve LDL-C goals. We compared the effects of rosuvastatin and atorvastatin in reducing LDL-C and achieving LDL-C goals in patients with primary hypercholesterolemia. Methods and Results: In this 52-week, randomized, double-blind, multicenter trial (4522IL/0026), 412 patients with LDL-C 160 to <250 mg/dL received a 5-mg dose of rosuvastatin (n = 138), a 10-mg dose of rosuvastatin (n = 134), or a 10-mg dose of atorvastatin (n = 140) for 12 weeks, during the following 40 weeks, dosages could be sequentially doubled up to 80 mg if National Cholesterol Education Program Adult Treatment Panel II (ATP-II) LDL-C goals were not achieved. At 12 weeks, 5- and 10-mg doses of rosuvastatin were associated with significantly greater LDL-C reductions than 10-mg doses of atorvastatin (46% and 50% vs 39%, both P < .001). At 12 weeks, both rosuvastatin dosages brought more patients to within ATP-II and European LDL-C goals than atorvastatin (86% and 89% vs 73% and 75%, and 86% vs 55%, respectively). At 52 weeks, compared with atorvastatin, both initial rosuvastatin treatment groups significantly reduced LDL-C (47% and 53% vs 44%, P < .05 and P < .001). Overall, more patients in the initial rosuvastatin 10-mg group achieved their ATP-II LDL-C goal than those in the initial atorvastatin 10-mg group (98% vs 87%), with 82% of patients treated with rosuvastatin achieving their goal at the 10-mg starting dosage without the need for titration, compared with 59% of patients treated with atorvastatin. Both treatments were well tolerated over 52 weeks. Conclusion: Compared with atorvastatin, rosuvastatin produced greater reductions in LDL-C, which may offer advantages in LDL-C goal attainment over existing lipid-lowering therapies.
23.	Shvartzvald, Yossi, et al. (author) Spitzer Microlensing Parallax for OGLE-2017-BLG-0896 Reveals a Counter-rotating Low-mass Brown Dwarf 2019 In: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 157:3 Journal article (peer-reviewed)abstract The kinematics of isolated brown dwarfs in the Galaxy, beyond the solar neighborhood, is virtually unknown. Microlensing has the potential to probe this hidden population, as it can measure both the mass and five of the six phase-space coordinates (all except the radial velocity) even of a dark isolated lens. However, the measurements of both the microlens-parallax and finite-source effects are needed in order to recover the full information. Here, we combine the Spitzer satellite parallax measurement with the ground-based light curve, which exhibits strong finite-source effects, of event OGLE-2017-BLG-0896. We find two degenerate solutions for the lens (due to the known satellite-parallax degeneracy), which are consistent with each other except for their proper motion. The lens is an isolated brown dwarf with a mass of either 18 +/- 1 M-J or 20 +/- 1 M-J. This is the lowest isolated-object mass measurement to date, only similar to 45% more massive than the theoretical deuterium-fusion boundary at solar metallicity, which is the common definition of a free-floating planet. The brown dwarf is located at either 3.9 +/- 0.1 kpc or 4.1 +/- 0.1 kpc toward the Galactic bulge, but with proper motion in the opposite direction of disk stars, with one solution suggesting it is moving within the Galactic plane. While it is possibly a halo brown dwarf, it might also represent a different, unknown population.
24.	Sopena Moros, Arturo, et al. (author) Tracking Cavity Formation in Electron Solvation : Insights from X-ray Spectroscopy and Theory 2024 In: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 146:5, s. 3262-3269 Journal article (peer-reviewed)abstract We present time-resolved X-ray absorption spectra of ionized liquid water and demonstrate that OH radicals, H3O+ ions, and solvated electrons all leave distinct X-ray-spectroscopic signatures. Particularly, this allows us to characterize the electron solvation process through a tool that focuses on the electronic response of oxygen atoms in the immediate vicinity of a solvated electron. Our experimental results, supported by ab initio calculations, confirm the formation of a cavity in which the solvated electron is trapped. We show that the solvation dynamics are governed by the magnitude of the random structural fluctuations present in water. As a consequence, the solvation time is highly sensitive to temperature and to the specific way the electron is injected into water.

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