45 research outputs found

    Gaia Focused Product Release: Sources from Service Interface Function image analysis

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    Context. Gaia’s readout window strategy is challenged by very dense fields in the sky. Therefore, in addition to standard Gaia observations, full Sky Mapper (SM) images were recorded for nine selected regions in the sky. A new software pipeline exploits these Service Interface Function (SIF) images of crowded fields (CFs), making use of the availability of the full two-dimensional (2D) information. This new pipeline produced half a million additional Gaia sources in the region of the omega Centauri (ω Cen) cluster, which are published with this Focused Product Release. We discuss the dedicated SIF CF data reduction pipeline, validate its data products, and introduce their Gaia archive table. Aims. Our aim is to improve the completeness of the Gaia source inventory in a very dense region in the sky, ω Cen. Methods. An adapted version of Gaia’s Source Detection and Image Parameter Determination software located sources in the 2D SIF CF images. These source detections were clustered and assigned to new SIF CF or existing Gaia sources by Gaia s cross-match software. For the new sources, astrometry was calculated using the Astrometric Global Iterative Solution software, and photometry was obtained in the Gaia DR3 reference system. We validated the results by comparing them to the public Gaia DR3 catalogue and external Hubble Space Telescope data. Results. With this Focused Product Release, 526 587 new sources have been added to the Gaia catalogue in ω Cen. Apart from positions and brightnesses, the additional catalogue contains parallaxes and proper motions, but no meaningful colour information. While SIF CF source parameters generally have a lower precision than nominal Gaia sources, in the cluster centre they increase the depth of the combined catalogue by three magnitudes and improve the source density by a factor of ten. Conclusions. This first SIF CF data publication already adds great value to the Gaia catalogue. It demonstrates what to expect for the fourth Gaia catalogue, which will contain additional sources for all nine SIF CF regions

    Gaia Focused Product Release: Asteroid orbital solution: Properties and assessment

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    Context. We report the exploitation of a sample of Solar System observations based on data from the third Gaia Data Release (Gaia DR3) of nearly 157 000 asteroids. It extends the epoch astrometric solution over the time coverage planned for the Gaia DR4, which is not expected before the end of 2025. This data set covers more than one full orbital period for the vast majority of these asteroids. The orbital solutions are derived from the Gaia data alone over a relatively short arc compared to the observation history of many of these asteroids. Aims. The work aims to produce orbital elements for a large set of asteroids based on 66 months of accurate astrometry provided by Gaia and to assess the accuracy of these orbital solutions with a comparison to the best available orbits derived from independent observations. A second validation is performed with accurate occultation timings. Methods. We processed the raw astrometric measurements of Gaia to obtain astrometric positions of moving objects with 1D sub-mas accuracy at the bright end. For each asteroid that we matched to the data, an orbit fitting was attempted in the form of the best fit of the initial conditions at the median epoch. The force model included Newtonian and relativistic accelerations to derive the observation equations, which were solved with a linear least-squares fit. Results. Orbits are provided in the form of state vectors in the International Celestial Reference Frame for 156 764 asteroids, including near-Earth objects, main-belt asteroids, and Trojans. For the asteroids with the best observations, the (formal) relative uncertainty σa/a is better than 10−10. Results are compared to orbits available from the Jet Propulsion Laboratory and MPC. Their orbits are based on much longer data arcs, but from positions of lower quality. The relative differences in semi-major axes have a mean of 5 × 10−10 and a scatter of 5 × 10−9

    Gaia Focused Product Release: Spatial distribution of two diffuse interstellar bands

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    Diffuse interstellar bands (DIBs) are absorption features seen in optical and infrared spectra of stars and extragalactic objects that are probably caused by large and complex molecules in the galactic interstellar medium (ISM). Here we investigate the Galactic distribution and properties of two DIBs identified in almost six million stellar spectra collected by the Gaia Radial Velocity Spectrometer. These measurements constitute a part of the Gaia Focused Product Release to be made public between the Gaia DR3 and DR4 data releases. In order to isolate the DIB signal from the stellar features in each individual spectrum, we identified a set of 160 000 spectra at high Galactic latitudes (|b| ⩾ 65°) covering a range of stellar parameters which we consider to be the DIB-free reference sample. Matching each target spectrum to its closest reference spectra in stellar parameter space allowed us to remove the stellar spectrum empirically, without reference to stellar models, leaving a set of six million ISM spectra. Using the star’s parallax and sky coordinates, we then allocated each ISM spectrum to a voxel (VOlume piXEL) on a contiguous three-dimensional grid with an angular size of 1.8° (level 5 HEALPix) and 29 unequally sized distance bins. Identifying the two DIBs at 862.1 nm (λ862.1) and 864.8 nm (λ864.8) in the stacked spectra, we modelled their shapes and report the depth, central wavelength, width, and equivalent width (EW) for each, along with confidence bounds on these measurements. We then explored the properties and distributions of these quantities and compared them with similar measurements from other surveys. Our main results are as follows: (1) the strength and spatial distribution of the DIB λ862.1 are very consistent with what was found in Gaia DR3, but for this work we attained a higher signal-to-noise ratio in the stacked spectra to larger distances, which allowed us to trace DIBs in the outer spiral arm and beyond the Scutum–Centaurus spiral arm; (2) we produced an all-sky map below ±65° of Galactic latitude to ~4000 pc of both DIB features and their correlations; (3) we detected the signals of DIB λ862.1 inside the Local Bubble (≲200 pc); and (4) there is a reasonable correlation with the dust reddening found from stellar absorption and EWs of both DIBs with a correlation coefficient of 0.90 for λ862.1 and 0.77 for λ864.8

    Gaia Focused Product Release: Radial velocity time series of long-period variables

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    Context. The third Gaia Data Release (DR3) provided photometric time series of more than 2 million long-period variable (LPV) candidates. Anticipating the publication of full radial-velocity data planned with Data Release 4, this Focused Product Release (FPR) provides radial-velocity time series for a selection of LPV candidates with high-quality observations. Aims. We describe the production and content of the Gaia catalog of LPV radial-velocity time series, and the methods used to compute the variability parameters published as part of the Gaia FPR. Methods. Starting from the DR3 catalog of LPV candidates, we applied several filters to construct a sample of sources with high-quality radial-velocity measurements. We modeled their radial-velocity and photometric time series to derive their periods and amplitudes, and further refined the sample by requiring compatibility between the radial-velocity period and at least one of the G, GBP, or GRP photometric periods. Results. The catalog includes radial-velocity time series and variability parameters for 9614 sources in the magnitude range 6 ≲ G/mag ≲ 14, including a flagged top-quality subsample of 6093 stars whose radial-velocity periods are fully compatible with the values derived from the G, GBP, and GRP photometric time series. The radial-velocity time series contain a mean of 24 measurements per source taken unevenly over a duration of about three years. We identify the great majority of the sources (88%) as genuine LPV candidates, with about half of them showing a pulsation period and the other half displaying a long secondary period. The remaining 12% of the catalog consists of candidate ellipsoidal binaries. Quality checks against radial velocities available in the literature show excellent agreement. We provide some illustrative examples and cautionary remarks. Conclusions. The publication of radial-velocity time series for almost ten thousand LPV candidates constitutes, by far, the largest such database available to date in the literature. The availability of simultaneous photometric measurements gives a unique added value to the Gaia catalog

    Efeitos do alongamento muscular e condicionamento físico no tratamento fisioterápico de pacientes com fibromialgia Effects of muscle stretching and physical conditioning as physical therapy treatment for patients with fibromyalgia

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    OBJETIVO: Verificar os efeitos de exercícios de alongamento muscular e condicionamento físico no tratamento fisioterápico da fibromialgia (FM). CASUÍSTICA E MÉTODOS: Foram avaliadas 15 mulheres com diagnóstico de FM, segundo os critérios do Colégio Americano de Reumatologia, divididas em dois grupos: Grupo 1 (G1) com oito pacientes, realizou tratamento por meio de alongamentos musculares e Grupo 2 (G2), sete pacientes, condicionamento físico. Foram avaliados qualidade do sono, fatores de piora e melhora da dor, sintomas associados e medicamentos utilizados. Além disso, foi aplicado o Fibromyalgia Impact Questionnaire (FIQ), para avaliar o impacto da FM. O tratamento durou oito semanas, sendo uma sessão semanal com duração de 40 a 45 minutos. As variáveis do FIQ antes e depois dos tratamentos foram comparadas pelo teste t para amostras dependentes (alfa< 0,05) e as demais foram analisadas descritivamente. RESULTADOS: A maioria das pacientes apresentava sono não reparador (86,67%), piora da dor com serviços domésticos (40%), nenhum fator de melhora da dor (28,57%), distúrbios do sono como sintomas associados (100%) e utilizava antidepressivos (69,23%). Em relação às variáveis do FIQ, observaram-se diferenças estatisticamente significantes no sono (p= 0,0428) e rigidez matinal (p= 0,0130) nas pacientes do G1. Já no G2, não foram observadas diferenças significantes após o tratamento. CONCLUSÕES: Sugere-se que os alongamentos musculares realizados podem gerar impacto positivo na FM, promovendo melhora do sono e rigidez matinal das pacientes avaliadas.<br>OBJECTIVE: To investigate the effects of muscle stretching exercises and physical conditioning as physical therapy treatment for fibromyalgia. METHODS: Fifteen women with a diagnosis of fibromyalgia in accordance with the criteria of the American College of Rheumatology were evaluated and divided into two groups: Group 1 (G1, eight patients) underwent treatment consisting of muscle stretching and Group 2 (G2, seven patients), participated in a physical conditioning program. Sleep quality, pain-modulating factors, associated symptoms and medications used were evaluated. Furthermore, the Fibromyalgia Impact Questionnaire (FIQ) was applied to evaluate the impact of fibromyalgia. The treatment lasted for eight weeks, with one session per week of 40 to 45 minutes in duration. The FIQ data obtained before and after treatment were analyzed by means of Student’s t test for dependent samples (alpha< 0.05) and other variables were analyzed descriptively. RESULTS: Most of the patients presented poor quality of sleep (86.67%). Many presented worsening of their pain when doing domestic tasks (40%) and there were no factors that relieved their pain (28.57%). All presented sleep disorders with associated symptoms (100%) and most used antidepressives (69.23%). For the FIQ data, statistically significant differences were observed in morning tiredness (p= 0.0428) and stiffness (p= 0.0130) among the G1 patients. Conversely, no difference was observed in G2 after the treatment. CONCLUSIONS: It is suggested that the muscle stretching may have had a positive impact on fibromyalgia, with reductions in morning tiredness and stiffness among the patients evaluated

    Relationship between jumping to conclusions and clinical outcomes in people at clinical high-risk for psychosis.

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    BACKGROUND: Psychosis is associated with a reasoning bias, which manifests as a tendency to 'jump to conclusions'. We examined this bias in people at clinical high-risk for psychosis (CHR) and investigated its relationship with their clinical outcomes. METHODS: In total, 303 CHR subjects and 57 healthy controls (HC) were included. Both groups were assessed at baseline, and after 1 and 2 years. A 'beads' task was used to assess reasoning bias. Symptoms and level of functioning were assessed using the Comprehensive Assessment of At-Risk Mental States scale (CAARMS) and the Global Assessment of Functioning (GAF), respectively. During follow up, 58 (16.1%) of the CHR group developed psychosis (CHR-T), and 245 did not (CHR-NT). Logistic regressions, multilevel mixed models, and Cox regression were used to analyse the relationship between reasoning bias and transition to psychosis and level of functioning, at each time point. RESULTS: There was no association between reasoning bias at baseline and the subsequent onset of psychosis. However, when assessed after the transition to psychosis, CHR-T participants showed a greater tendency to jump to conclusions than CHR-NT and HC participants (55, 17, 17%; χ2 = 8.13, p = 0.012). There was a significant association between jumping to conclusions (JTC) at baseline and a reduced level of functioning at 2-year follow-up in the CHR group after adjusting for transition, gender, ethnicity, age, and IQ. CONCLUSIONS: In CHR participants, JTC at baseline was associated with adverse functioning at the follow-up. Interventions designed to improve JTC could be beneficial in the CHR population
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