1,635 research outputs found
Radial velocities from the N2K Project: 6 new cold gas giant planets orbiting HD 55696, HD 98736, HD 148164, HD 203473, and HD 211810
The N2K planet search program was designed to exploit the planet-metallicity
correlation by searching for gas giant planets orbiting metal-rich stars. Here,
we present the radial velocity measurements for 378 N2K target stars that were
observed with the HIRES spectrograph at Keck Observatory between 2004 and 2017.
With this data set, we announce the discovery of six new gas giant exoplanets:
a double-planet system orbiting HD 148164 ( of 1.23 and 5.16 M) and single planet detections around HD 55696 ( = 3.87 M), HD 98736 ( = 2.33 M), HD 203473 ( = 7.8
M), and HD 211810 ( = 0.67 M). These gas
giant companions have orbital semi-major axes between 1.0 and 6.2 AU and
eccentricities ranging from 0.13 to 0.71. We also report evidence for three
gravitationally bound companions with between 20 to 30 M, placing them in the mass range of brown dwarfs, around HD 148284, HD
214823, and HD 217850, and four low mass stellar companions orbiting HD 3404,
HD 24505, HD 98630, and HD 103459. In addition, we present updated orbital
parameters for 42 previously announced planets. We also report a nondetection
of the putative companion HD 73256 b. Finally, we highlight the most promising
candidates for direct imaging and astrometric detection, and find that many hot
Jupiters from our sample could be detectable by state-of-the-art telescopes
such as Gaia.Comment: Accepted by the Astronomical Journal. 75 pages, 49 figure
Recommended from our members
Functional Analysis of a Novel Potassium Channel (KCNA1) Mutation in Hereditary Mokymia
Myokymia is characterized by spontaneous, involuntary muscle fiber group contraction visible as vermiform movement of the overlying skin. Myokymia with episodic ataxia is a rare, autosomal dominant trait caused by mutations in KCNA1, encoding a voltage-gated potassium channel. In the present study, we report a family with four members affected with myokymia. Additional clinical features included motor delay initially diagnosed as cerebral palsy, worsening with febrile illness, persistent extensor plantar reflex, and absence of epilepsy or episodic ataxia. Mutation analysis revealed a novel c.676C>A substitution in the potassium channel gene KCNA1, resulting in a T226K nonconservative missense mutation in the Kv1.1 subunit in all affected individuals. Electrophysiological studies of the mutant channel expressed in Xenopus oocytes indicated a loss of function. Co-expression of WT and mutant cRNAs significantly reduced whole-oocyte current compared to expression of WT Kv1.1 alone
Piecing together
2003 Fall.Includes bibliographical references (page 10).To view the abstract, please see the full text of the document
Reproducing Walter Benjamin's the work of art in the age of mechanical reproduction
AR 515.8 December 1999.Includes bibliographic references (page 14)
Ecologia de serveis, càmping i medi ambient, ecoetiquetes : Parc Natural de l'Alt Pirineu
El present projecte té per motiu l'anàlisi de l'estat ambiental dels càmpings a l'entorn del Parc Natural de l'Alt Pirineu. L'estudi del Distintiu de Garantia de Qualitat Ambiental (DGQA) suposa en aquest àmbit una eina d'estudi més que una finalitat, en la qual es basa el projecte per l'anàlisi proposat.El presente proyecto tiene por motivo el análisis del estado ambiental de los campings en el entorno del Parque Natural del Alto Pirineo. El estudio del Distintiu de Garantia de Qualitat Ambiental (DGQA) supone en este ámbito un instrumento de estudio más que una finalidad, en el cual se basa el proyecto para el análisis propuesto.This project intends to assess the environmental conditions of the "Parc Natural de l'Alt Pirineu". The essay of the Environmental Quality Distinctive watched out by the Generalitat de Catalunya implies in that field an studying skill more than an aim in which the project is based upon it
TESS Discovery of an ultra-short-period planet around the nearby M dwarf LHS 3844
Data from the newly-commissioned \textit{Transiting Exoplanet Survey
Satellite} (TESS) has revealed a "hot Earth" around LHS 3844, an M dwarf
located 15 pc away. The planet has a radius of and
orbits the star every 11 hours. Although the existence of an atmosphere around
such a strongly irradiated planet is questionable, the star is bright enough
(, ) for this possibility to be investigated with transit and
occultation spectroscopy. The star's brightness and the planet's short period
will also facilitate the measurement of the planet's mass through Doppler
spectroscopy.Comment: 10 pages, 4 figures. Submitted to ApJ Letters. This letter makes use
of the TESS Alert data, which is currently in a beta test phase, using data
from the pipelines at the TESS Science Office and at the TESS Science
Processing Operations Cente
Indications for, timing of, and modes of delivery in a national cohort of women admitted with antepartum hemorrhage at 22+0 to 28+6 weeks' gestation.
OBJECTIVE: Antepartum hemorrhage is associated with preterm birth and operative delivery. Since the Canadian Perinatal Network records obstetric interventions for women admitted to tertiary care hospitals with antepartum hemorrhage, our objective was to describe the delivery characteristics of this cohort. METHODS: Trained abstractors collected data by chart review from women admitted with antepartum hemorrhage between 22+0 and 28+6 weeks' gestation. We included all women with complete follow-up postpartum and used descriptive statistics to report the indications for, timing of, and modes of delivery. RESULTS: The study cohort included 806 women from 13 tertiary perinatal centres in six provinces. The most common causes of bleeding were placental abruption (n = 256) and placenta previa (n = 171). The median gestational age at delivery was 30 weeks, and 497 (61.7%) births occurred at less than 34 weeks. Over one half of the women began labour spontaneously, and 238 (29.5%) were delivered prior to the onset of labour. Overall, 370 (45.9%) women delivered vaginally, including 98 who had induction of labour. Of the 436 Caesarean sections (54.1%), 345 (79.1%) were emergencies. The most common indications for Caesarean section were placenta previa, abnormal fetal presentation, and placental abruption or vaginal bleeding. CONCLUSION: This inpatient cohort of women with antepartum hemorrhage had high rates of spontaneous labour, preterm birth, and emergency Caesarean section. These results can be used as current Canadian benchmark rates of preterm delivery, induction of labour, and Caesarean section in women admitted to tertiary care centres with antepartum hemorrhage between 22+0 and 28+6 weeks' gestation, and can aid in the counselling of similar women
RoboTAP: Target priorities for robotic microlensing observations
Context. The ability to automatically select scientifically-important transient events from an alert stream of many such events, and to conduct follow-up observations in response, will become increasingly important in astronomy. With wide-angle time domain surveys pushing to fainter limiting magnitudes, the capability to follow-up on transient alerts far exceeds our follow-up telescope resources, and effective target prioritization becomes essential. The RoboNet-II microlensing program is a pathfinder project, which has developed an automated target selection process (RoboTAP) for gravitational microlensing events, which are observed in real time using the Las Cumbres Observatory telescope network.
Aims. Follow-up telescopes typically have a much smaller field of view compared to surveys, therefore the most promising microlensing events must be automatically selected at any given time from an annual sample exceeding 2000 events. The main challenge is to select between events with a high planet detection sensitivity, with the aim of detecting many planets and characterizing planetary anomalies.
Methods. Our target selection algorithm is a hybrid system based on estimates of the planet detection zones around a microlens. It follows automatic anomaly alerts and respects the expected survey coverage of specific events.
Results. We introduce the RoboTAP algorithm, whose purpose is to select and prioritize microlensing events with high sensitivity to planetary companions. In this work, we determine the planet sensitivity of the RoboNet follow-up program and provide a working example of how a broker can be designed for a real-life transient science program conducting follow-up observations in response to alerts; we explore the issues that will confront similar programs being developed for the Large Synoptic Survey Telescope (LSST) and other time domain surveys
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