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BACKGROUND: Video consultation is a possibility for physician-patient communication independent of the location; however, only limited information is available for the possibility of sole use since 2018. METHODS: After the implementation of video consultation (Viomedi) in lipid consultations at the Medical University Mainz, the patients in the first quarter of 2022 were assessed depending on the possibility, suitability and readiness to participate. Included were patients under lipid management and long COVID patients. After treatment an online survey was carried out on the utilization and appraisal. RESULTS: Of the 134 patients 29.1% were inclusively treated (3 refusals). All subjects (16 replies) reported having managed (very) well. Advantages were seen in counselling and follow-up. Problems were feared with respect to technology and possible disorders. Data protection aspects played a subordinate role. In comparison to telephone calls, a significant improvement in the physician-patient relationship (p-valueâ¯= 0.00027), the quality of treatment and information (p-value bothâ¯= 0.00044), the access to care (p-valueâ¯= 0.0053) and the communication (p-valueâ¯= 0.021) was assumed. An improvement in access to care (p-valueâ¯= 0.021) and the quality of information (p-valueâ¯= 0.034) was seen in comparison to personal contact. The main problems were a lack of experience, technical requirements, technical problems and unpunctuality of the practitioner. The flexibility, low effort and the pleasant consultation were all praised. All subjects wanted to use the video consultation again. CONCLUSION: Video consultation can represent a supplement to treatment of patients under lipid management. The correct use requires exact planning and further research.
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Fast radio bursts (FRBs) are millisecond-duration pulses of radio emission originating from extragalactic distances. Radio dispersion is imparted on each burst by intervening plasma, mostly located in the intergalactic medium. In this work, we observe the burst FRB 20220610A and localize it to a morphologically complex host galaxy system at redshift 1.016 ± 0.002. The burst redshift and dispersion measure are consistent with passage through a substantial column of plasma in the intergalactic medium and extend the relationship between those quantities measured at lower redshift. The burst shows evidence for passage through additional turbulent magnetized plasma, potentially associated with the host galaxy. We use the burst energy of 2 × 1042 erg to revise the empirical maximum energy of an FRB.
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Fair inclusion of research subjects is necessary to ensure that post-acute sequelae COVID-19 (PASC) research results benefit all members of society. Scientists should conduct research on a broad sample of individuals who represent clinically relevant factors influencing a disease. Without demographic diversity and sociological and environmental variability, research outputs are less likely to apply to different populations and would thus increase health disparities. The goal of this narrative literature review and ethical analysis is to apply fair selection criteria to PASC research studies. We briefly highlight the importance of fair subject selection in translational research and then identify features of PASC, as well as PASC research, that hinder fair inclusion of research participants. We will demonstrate that determining an adequate and representative sample is not simply a matter of ensuring greater diversity; rather, fairness requires a broader evaluation of risks, burdens, and benefits specific to underrepresented populations. We provide recommendations to ensure fair subject selection in PASC research and promote translation toward positive health outcomes for all individuals, including the most vulnerable.
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We introduce CosmoVis, an open source web-based visualization tool for the interactive analysis of massive hydrodynamic cosmological simulation data. CosmoVis was designed in close collaboration with astrophysicists to enable researchers and citizen scientists to share and explore these datasets, and to use them to investigate a range of scientific questions. CosmoVis visualizes many key gas, dark matter, and stellar attributes extracted from the source simulations, which typically consist of complex data structures multiple terabytes in size, often requiring extensive data wrangling. CosmoVis introduces a range of features to facilitate real-time analysis of these simulations, including the use of "virtual skewers," simulated analogues of absorption line spectroscopy that act as spectral probes piercing the volume of gaseous cosmic medium. We explain how such synthetic spectra can be used to gain insight into the source datasets and to make functional comparisons with observational data. Furthermore, we identify the main analysis tasks that CosmoVis enables and present implementation details of the software interface and the client-server architecture. We conclude by providing details of three contemporary scientific use cases that were conducted by domain experts using the software and by documenting expert feedback from astrophysicists at different career levels.
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We present Monte Carlo Physarum Machine (MCPM): a computational model suitable for reconstructing continuous transport networks from sparse 2D and 3D data. MCPM is a probabilistic generalization of Jones's (2010) agent-based model for simulating the growth of Physarum polycephalum (slime mold). We compare MCPM to Jones's work on theoretical grounds, and describe a task-specific variant designed for reconstructing the large-scale distribution of gas and dark matter in the Universe known as the cosmic web. To analyze the new model, we first explore MCPM's self-patterning behavior, showing a wide range of continuous network-like morphologies-called polyphorms-that the model produces from geometrically intuitive parameters. Applying MCPM to both simulated and observational cosmological data sets, we then evaluate its ability to produce consistent 3D density maps of the cosmic web. Finally, we examine other possible tasks where MCPM could be useful, along with several examples of fitting to domain-specific data as proofs of concept.
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Physarum polycephalum , PhysarumRESUMEN
BACKGROUND: Health behavior change interventions delivered by social media allow for real-time, dynamic interaction, peer social support, and experimenter-provided content. AIMS: We tested the feasibility, acceptability, and preliminary efficacy of a novel Twitter-based walking break intervention with daily behavior change strategies and prompts for social support, combined with a Fitbit, vs. Fitbit alone. METHODS: In a 2-group pilot, 45 sedentary women from a heart clinic were randomized to Twitter + Fitbit activity tracker (Tweet4Wellness, n = 23) or Fitbit-only (control, n = 22). All received a Fitbit and 13 weeks of tailored weekly step goals. Tweet4Wellness consisted of a private Twitter support group, with daily automated behavior change "tweets" informed by behavior change theory, and encouragement to communicate within the group. Feasibility outcomes included recruitment and enrollment numbers, implementation challenges, and number and type of help requests from participants throughout the study period. Preliminary efficacy outcomes provided by Fitbit data were sedentary minutes, number of hours with >250 steps, maximum sitting bout, weighted sedentary median bout length, total steps, intensity minutes (>3.0 METS), and ratio of time spent sitting-to-moving. Acceptability outcomes included level of Twitter participation within Tweet4Wellness, and Likert scale plus open-ended survey questions on enjoyment and perceived effectiveness of intervention components. Survey data on acceptability of the features of the intervention were collected at 13 weeks (end-of-treatment [EOT]) and 22 weeks (follow-up). RESULTS: The study was feasible, with addressable implementation challenges. Tweet4Wellness participants changed significantly from baseline to EOT relative to control participants on number of active hours p = .018, total steps p = .028, and ratio of sitting-to-moving, p = .014. Only sitting-to-moving was significant at follow-up (p = .047). Among Tweet4Wellness participants, each tweet sent during treatment was associated with a 0.11 increase in active hours per day (p = .04) and a 292-step increase per day (p < .001). Tweet4Wellness participants averaged 54.8 (SD = 35.4) tweets, totaling 1304 tweets, and reported liking the accountability and peer support provided by the intervention. CONCLUSION: A Twitter-delivered intervention for promoting physical activity among inactive women from a heart clinic was feasible, acceptable, and demonstrated preliminary efficacy in increasing daily active hours, daily total steps, and the ratio of sitting-to-moving from pre to post for the intervention compared with the control. Lessons learned from this pilot suggest that the next study should expand the recruitment pool, refine the intervention to increase group engagement, and select active hours, total steps, and ratio of sitting-to-movement as primary sedentary behavior measures.
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This paper introduces Polyphorm, an interactive visualization and model fitting tool that provides a novel approach for investigating cosmological datasets. Through a fast computational simulation method inspired by the behavior of Physarum polycephalum, an unicellular slime mold organism that efficiently forages for nutrients, astrophysicists are able to extrapolate from sparse datasets, such as galaxy maps archived in the Sloan Digital Sky Survey, and then use these extrapolations to inform analyses of a wide range of other data, such as spectroscopic observations captured by the Hubble Space Telescope. Researchers can interactively update the simulation by adjusting model parameters, and then investigate the resulting visual output to form hypotheses about the data. We describe details of Polyphorm's simulation model and its interaction and visualization modalities, and we evaluate Polyphorm through three scientific use cases that demonstrate the effectiveness of our approach.
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Physarum polycephalum , Gráficos por Computador , Simulación por ComputadorRESUMEN
Massive disk galaxies like the Milky Way are expected to form at late times in traditional models of galaxy formation1,2, but recent numerical simulations suggest that such galaxies could form as early as a billion years after the Big Bang through the accretion of cold material and mergers3,4. Observationally, it has been difficult to identify disk galaxies in emission at high redshift5,6 in order to discern between competing models of galaxy formation. Here we report imaging, with a resolution of about 1.3 kiloparsecs, of the 158-micrometre emission line from singly ionized carbon, the far-infrared dust continuum and the near-ultraviolet continuum emission from a galaxy at a redshift of 4.2603, identified by detecting its absorption of quasar light. These observations show that the emission arises from gas inside a cold, dusty, rotating disk with a rotational velocity of about 272 kilometres per second. The detection of emission from carbon monoxide in the galaxy yields a molecular mass that is consistent with the estimate from the ionized carbon emission of about 72 billion solar masses. The existence of such a massive, rotationally supported, cold disk galaxy when the Universe was only 1.5 billion years old favours formation through either cold-mode accretion or mergers, although its large rotational velocity and large content of cold gas remain challenging to reproduce with most numerical simulations7,8.
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More than three-quarters of the baryonic content of the Universe resides in a highly diffuse state that is difficult to detect, with only a small fraction directly observed in galaxies and galaxy clusters1,2. Censuses of the nearby Universe have used absorption line spectroscopy3,4 to observe the 'invisible' baryons, but these measurements rely on large and uncertain corrections and are insensitive to most of the Universe's volume and probably most of its mass. In particular, quasar spectroscopy is sensitive either to the very small amounts of hydrogen that exist in the atomic state, or to highly ionized and enriched gas4-6 in denser regions near galaxies7. Other techniques to observe these invisible baryons also have limitations; Sunyaev-Zel'dovich analyses8,9 can provide evidence from gas within filamentary structures, and studies of X-ray emission are most sensitive to gas near galaxy clusters9,10. Here we report a measurement of the baryon content of the Universe using the dispersion of a sample of localized fast radio bursts; this technique determines the electron column density along each line of sight and accounts for every ionized baryon11-13. We augment the sample of reported arcsecond-localized14-18 fast radio bursts with four new localizations in host galaxies that have measured redshifts of 0.291, 0.118, 0.378 and 0.522. This completes a sample sufficiently large to account for dispersion variations along the lines of sight and in the host-galaxy environments11, and we derive a cosmic baryon density of [Formula: see text] (95 per cent confidence; h70 = H0/(70 km s-1 Mpc-1) and H0 is Hubble's constant). This independent measurement is consistent with values derived from the cosmic microwave background and from Big Bang nucleosynthesis19,20.
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Present-day galaxies are surrounded by cool and enriched halo gas extending for hundreds of kiloparsecs. This halo gas is thought to be the dominant reservoir of material available to fuel future star formation, but direct constraints on its mass and physical properties have been difficult to obtain. We report the detection of a fast radio burst (FRB 181112), localized with arcsecond precision, that passes through the halo of a foreground galaxy. Analysis of the burst shows that the halo gas has low net magnetization and turbulence. Our results imply predominantly diffuse gas in massive galactic halos, even those hosting active supermassive black holes, contrary to some previous results.
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Several clinical, genetic and acquired risk factors for venous thromboembolism (VTE) have been identified. However, the molecular pathophysiology and mechanisms of disease progression remain poorly understood. This is reflected by uncertainties regarding the primary and secondary prevention of VTE and the optimal duration of antithrombotic therapy. A growing body of literature points to clinically relevant differences between VTE phenotypes (e.g. deep vein thrombosis (DVT) versus pulmonary embolism (PE), unprovoked versus provoked VTE). Extensive links to cardiovascular, inflammatory and immune-related morbidities are testament to the complexity of the disease. The GMP-VTE project is a prospective, multi-center cohort study on individuals with objectively confirmed VTE. Sequential data sampling was performed at the time of the acute event and during serial follow-up investigations. Various data levels (e.g. clinical, genetic, proteomic and platelet data) are available for multi-dimensional data analyses by means of advanced statistical, bioinformatic and machine learning methods. The GMP-VTE project comprises nâ¯=â¯663 individuals with acute VTE (mean age: 60.3⯱â¯15.9â¯years; female sex: 42.8%). In detail, 28.4% individuals (nâ¯=â¯188) had acute isolated DVT, whereas 71.6% subjects (nâ¯=â¯475) had PE with or without concomitant DVT. In the study sample, 28.9% (nâ¯=â¯129) of individuals with PE and 30.1% (nâ¯=â¯55) of individuals with isolated DVT had a recurrent VTE event at the time of study enrolment. The systems-oriented approach for the comprehensive dataset of the GMP-VTE project may generate new biological insights into the pathophysiology of VTE and refine our current understanding and management of VTE.
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Tromboembolia Venosa/genética , Estudios de Cohortes , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Estudios Prospectivos , Factores de RiesgoRESUMEN
Fast radio bursts (FRBs) are brief radio emissions from distant astronomical sources. Some are known to repeat, but most are single bursts. Nonrepeating FRB observations have had insufficient positional accuracy to localize them to an individual host galaxy. We report the interferometric localization of the single-pulse FRB 180924 to a position 4 kiloparsecs from the center of a luminous galaxy at redshift 0.3214. The burst has not been observed to repeat. The properties of the burst and its host are markedly different from those of the only other accurately localized FRB source. The integrated electron column density along the line of sight closely matches models of the intergalactic medium, indicating that some FRBs are clean probes of the baryonic component of the cosmic web.
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Aims: The cardiac and vascular late sequelae in long-term survivors of childhood cancer (CVSS)-study aimed to quantify the prevalence of cardiovascular risk factors (CVRF) and cardiovascular disease (CVD) in German childhood cancer survivors (CCS). Methods and results: In the CVSS-study (NCT02181049), 1002 CCS (age range 23-48 years) diagnosed with neoplasia prior to 15 years of age between 1980 and 1990 prospectively underwent a systematic, standardized clinical and laboratory cardiovascular screening, identical to the population-based Gutenberg Health Study (GHS) cohort. For 951 individuals, prevalences of CVRF and CVD were primarily compared to the GHS sample and to two further German population-based cohorts. Using log-binomial regression models, an increased risk for occurrence of arterial hypertension [relative risk (RR) 1.38, 95% confidence interval (95% CI 1.21-1.57)] and dyslipidaemia [RR 1.26 (95% CI 1.12-1.42)] was found. This indicates a premature occurrence compared to the general population of approximately 6 and 8 years, respectively [rate advancement period estimator, RAPhypertension 5.75 (95% CI 3.5-8.0) and RAPdyslipidaemia 8.16 (95% CI 4.4-11.9)]. Overall, no differences were observed for obesity and diabetes. Overt CVD was present in 4.5% (95% CI 3.0-6.6%) of CCS [RR 1.89 (95% CI 1.34-2.66), RAPCVD 7.9 (95% CI 4.1-11.7)], of which the most frequent entities were congestive heart failure and venous thromboembolism. Prevalences of CVRF and CVD increased with age without reaching a plateau over time. Conclusion: This large CCS screening examination revealed consistently in comparison to three population samples a considerably increased risk for premature CVD. The findings in these young adult CCS indicate a high burden of cardiovascular morbidity and mortality in the long term. Clinicaltrials. gov-Nr: NCT02181049.
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Supervivientes de Cáncer/estadística & datos numéricos , Enfermedades Cardiovasculares/epidemiología , Adulto , Edad de Inicio , Comorbilidad , Diabetes Mellitus/epidemiología , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Prevalencia , Factores de Riesgo , Distribución por Sexo , Fumar/epidemiología , Adulto JovenRESUMEN
Essentials The increase of cancer survival remains curtailed by cardiovascular mortality. We studied a large range of inflammatory and coagulation biomarkers in long-term cancer survivors. Cancer history has an important impact on mortality independent of cardiovascular risk factors. Fibrinogen and von Willebrand factor are potential biomarkers in survivors of increased mortality. SUMMARY: Background The advances in cancer treatment and detection of early cancer have resulted in a steady increase in the number of of cancer survivors over the years. However, because of the long-term toxic effects of chemotherapy and radiotherapy, the incidence of cardiovascular disease (CVD) is increasing in survivors. Objectives To investigate traditional cardiovascular risk factors (CVRFs), inflammation and the coagulation profile in long-term cancer survivors (cancer diagnosis ≥ 5 years) from a large adult population-based study sample. Methods The presence of cardiovascular risk factors (CVRFs) and laboratory markers were compared in individuals with (n = 723) and without (n = 13626) a long-term history of cancer from the Gutenberg Health Study. Data on coagulation factors, D-dimer and von Willebrand factor (VWF) activity were available for 4974 individuals (n = 244 cancer survivors). Results In multivariable regression models, a history of cancer was, independently of CVRFs and CVD, associated with higher fibrinogen levels (ß 6.99, 95% confidence interval [CI] 1.16-12.8), VWF activity (ß 5.08, 95% CI 0.02-10.1), and antithrombin activity (ß 1.85, 95% CI 0.44-3.27). Cancer survivors with CVD showed notably higher VWF activity than individuals with CVD without a history of cancer, with a difference in the means of 23.0 (7.9-38.1). Multivariate Cox regression analysis, adjusted for CVRFs, confirmed that a long-term history of cancer is associated with a 72% higher mortality. Increased mortality in cancer survivors was dependent on fibrinogen level and VWF activity level. Conclusion Cancer survivors showed a worse inflammation and coagulation profile than individuals without a history of cancer. Overall mortality in long-term cancer survivors was increased independently of traditional CVRFs. These results underline the need to further investigate plasma biomarkers as complementary cardiovascular risk predictors in cancer survivors.
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Coagulación Sanguínea , Supervivientes de Cáncer , Enfermedades Cardiovasculares/sangre , Fibrinógeno/metabolismo , Mediadores de Inflamación/sangre , Inflamación/sangre , Factor de von Willebrand/metabolismo , Adulto , Anciano , Biomarcadores/sangre , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/mortalidad , Femenino , Alemania/epidemiología , Humanos , Inflamación/diagnóstico , Inflamación/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Factores de TiempoRESUMEN
The incidence of cardiovascular diseases can be reduced by the early detection and targeted treatment of risk factors and subclinical forms of the disease. Primary prevention provides several opportunities for successful interventions. In addition to a drug-based therapy, especially life style-modifying measures, such as physical activity, normalization of body weight, consistent nicotine abstinence and the consideration of psychosocial aspects represent core components of prevention programs. Healthcare data indicate that risk factors still often remain undetected and that the full potential of risk factor management has not yet been fully exploited at a population level. Especially motivation of patients and adherence to therapy represent key elements of successful prevention efforts.
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Enfermedades Cardiovasculares/prevención & control , Peso Corporal , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Diagnóstico Precoz , Intervención Médica Temprana , Ejercicio Físico , Alemania , Humanos , Incidencia , Estilo de Vida , Factores de Riesgo , Cese del Hábito de FumarRESUMEN
Atherothrombosis is a leading cause of cardiovascular mortality and long-term morbidity. Platelets and coagulation proteases, interacting with circulating cells and in different vascular beds, modify several complex pathologies including atherosclerosis. In the second Maastricht Consensus Conference on Thrombosis, this theme was addressed by diverse scientists from bench to bedside. All presentations were discussed with audience members and the results of these discussions were incorporated in the final document that presents a state-of-the-art reflection of expert opinions and consensus recommendations regarding the following five topics: 1. Risk factors, biomarkers and plaque instability: In atherothrombosis research, more focus on the contribution of specific risk factors like ectopic fat needs to be considered; definitions of atherothrombosis are important distinguishing different phases of disease, including plaque (in)stability; proteomic and metabolomics data are to be added to genetic information. 2. Circulating cells including platelets and atherothrombosis: Mechanisms of leukocyte and macrophage plasticity, migration, and transformation in murine atherosclerosis need to be considered; disease mechanism-based biomarkers need to be identified; experimental systems are needed that incorporate whole-blood flow to understand how red blood cells influence thrombus formation and stability; knowledge on platelet heterogeneity and priming conditions needs to be translated toward the in vivo situation. 3. Coagulation proteases, fibrin(ogen) and thrombus formation: The role of factor (F) XI in thrombosis including the lower margins of this factor related to safe and effective antithrombotic therapy needs to be established; FXI is a key regulator in linking platelets, thrombin generation, and inflammatory mechanisms in a renin-angiotensin dependent manner; however, the impact on thrombin-dependent PAR signaling needs further study; the fundamental mechanisms in FXIII biology and biochemistry and its impact on thrombus biophysical characteristics need to be explored; the interactions of red cells and fibrin formation and its consequences for thrombus formation and lysis need to be addressed. Platelet-fibrin interactions are pivotal determinants of clot formation and stability with potential therapeutic consequences. 4. Preventive and acute treatment of atherothrombosis and arterial embolism; novel ways and tailoring? The role of protease-activated receptor (PAR)-4 vis à vis PAR-1 as target for antithrombotic therapy merits study; ongoing trials on platelet function test-based antiplatelet therapy adjustment support development of practically feasible tests; risk scores for patients with atrial fibrillation need refinement, taking new biomarkers including coagulation into account; risk scores that consider organ system differences in bleeding may have added value; all forms of oral anticoagulant treatment require better organization, including education and emergency access; laboratory testing still needs rapidly available sensitive tests with short turnaround time. 5. Pleiotropy of coagulation proteases, thrombus resolution and ischaemia-reperfusion: Biobanks specifically for thrombus storage and analysis are needed; further studies on novel modified activated protein C-based agents are required including its cytoprotective properties; new avenues for optimizing treatment of patients with ischaemic stroke are needed, also including novel agents that modify fibrinolytic activity (aimed at plasminogen activator inhibitor-1 and thrombin activatable fibrinolysis inhibitor.
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Tromboembolia/terapia , Trombosis/sangre , Trombosis/terapia , Anticoagulantes/uso terapéutico , Biomarcadores/sangre , Coagulación Sanguínea , Eritrocitos/metabolismo , Factor VIII/metabolismo , Factor XII/metabolismo , Factor XIII/metabolismo , Humanos , Macrófagos/metabolismo , Países Bajos , Fenotipo , Placa Aterosclerótica/sangre , Placa Aterosclerótica/diagnóstico , Placa Aterosclerótica/terapia , Polifosfatos/metabolismo , Factores de Riesgo , Transducción de Señal , Tromboembolia/sangre , Tromboembolia/diagnóstico , Trombosis/diagnósticoRESUMEN
On 17 August 2017, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometer detected gravitational waves (GWs) emanating from a binary neutron star merger, GW170817. Nearly simultaneously, the Fermi and INTEGRAL (INTErnational Gamma-Ray Astrophysics Laboratory) telescopes detected a gamma-ray transient, GRB 170817A. At 10.9 hours after the GW trigger, we discovered a transient and fading optical source, Swope Supernova Survey 2017a (SSS17a), coincident with GW170817. SSS17a is located in NGC 4993, an S0 galaxy at a distance of 40 megaparsecs. The precise location of GW170817 provides an opportunity to probe the nature of these cataclysmic events by combining electromagnetic and GW observations.
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Eleven hours after the detection of gravitational wave source GW170817 by the Laser Interferometer Gravitational-Wave Observatory and Virgo Interferometers, an associated optical transient, SSS17a, was identified in the galaxy NGC 4993. Although the gravitational wave data indicate that GW170817 is consistent with the merger of two compact objects, the electromagnetic observations provide independent constraints on the nature of that system. We synthesize the optical to near-infrared photometry and spectroscopy of SSS17a collected by the One-Meter Two-Hemisphere collaboration, finding that SSS17a is unlike other known transients. The source is best described by theoretical models of a kilonova consisting of radioactive elements produced by rapid neutron capture (the r-process). We conclude that SSS17a was the result of a binary neutron star merger, reinforcing the gravitational wave result.
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On 17 August 2017, Swope Supernova Survey 2017a (SSS17a) was discovered as the optical counterpart of the binary neutron star gravitational wave event GW170817. We report time-series spectroscopy of SSS17a from 11.75 hours until 8.5 days after the merger. Over the first hour of observations, the ejecta rapidly expanded and cooled. Applying blackbody fits to the spectra, we measured the photosphere cooling from [Formula: see text] to [Formula: see text] kelvin, and determined a photospheric velocity of roughly 30% of the speed of light. The spectra of SSS17a began displaying broad features after 1.46 days and evolved qualitatively over each subsequent day, with distinct blue (early-time) and red (late-time) components. The late-time component is consistent with theoretical models of r-process-enriched neutron star ejecta, whereas the blue component requires high-velocity, lanthanide-free material.
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On 17 August 2017, gravitational waves (GWs) were detected from a binary neutron star merger, GW170817, along with a coincident short gamma-ray burst, GRB 170817A. An optical transient source, Swope Supernova Survey 17a (SSS17a), was subsequently identified as the counterpart of this event. We present ultraviolet, optical, and infrared light curves of SSS17a extending from 10.9 hours to 18 days postmerger. We constrain the radioactively powered transient resulting from the ejection of neutron-rich material. The fast rise of the light curves, subsequent decay, and rapid color evolution are consistent with multiple ejecta components of differing lanthanide abundance. The late-time light curve indicates that SSS17a produced at least ~0.05 solar masses of heavy elements, demonstrating that neutron star mergers play a role in rapid neutron capture (r-process) nucleosynthesis in the universe.