Search results for "star"
showing 10 items of 4285 documents
XMM observations of IC 2391 stars
2006
We present X-ray spectral and timing analysis of members of the young open cluster IC 2391 observed with the XMM-Newton observatory. We detected 99 X-ray sources by analysing the summed data obtained from MOS1, MOS2 and pn detectors of the EPIC camera; 24 of them are members, or probable members, of the cluster. Stars of all spectral types have been detected, from the early-types to the late-M dwarfs. Cone search capability for table J/A+A/430/287/table1 (XMM-Newton sources in the IC 2391 region, as detected in the combined EPIC image.) Cone search capability for table J/A+A/430/287/table2 (X-ray and optical properties of IC 2391 members, and upper limits in the combined EPIC image.)
uvby{beta} photometry of h and chi Per
2002
We present CCD uvby{beta} photometry for stars in the nuclei of the young double cluster {h} and {chi} Persei. We find that the reddening is highly variable through the {h} Per nucleus, increasing from west to east, with values ranging from E(b-y)=0.328+/-0.022 in the western part to E(b-y)=0.465+/-0.025 in the south-east. Towards {chi} Persei the reddening is fairly constant, with E(b-y)=0.398+/-0.025. Both clusters share a common distance modulus of 11.7+/-0.1mag, and an age of logt=7.10+/-0.05 years. Cone search capability for table J/A+A/394/479/table6 (Coordinates and photometry for stars in h Per) Cone search capability for table J/A+A/394/479/table7 (Coordinates and photometry for st…
NW Ser and V1446 Aql uvby light curves
2007
We present accurate photometric time series of two Be stars: NW Ser and V1446 Aql. Both stars were observed at the Observatorio de Sierra Nevada (Granada) in July 2003 with an automatic four-channel Stroemgren photometer. We also present a preliminary theoretical study showing that the periodic variations exhibited by these stars can be due to pulsation.
AB Dor A VLBI images
2020
The fast rotator, pre-main sequence star AB Dor A is a strong and persistent radio emitter. The extraordinary coronal flaring activity is thought to be the origin of compact radio emission and other associated phenomena, such as large slingshot prominences. We aim to investigate the radio emission mechanism and the milliarcsecond radio structure around AB Dor A. We performed phase-referenced VLBI observations at 22.3GHz, 8.4GHz, and 1.4GHz over more than one decade using the Australian VLBI array. Our 8.4GHz images show a double core-halo morphology, similar at all epochs, with emission extending at heights between 5 and 18 stellar radii. Furthermore, the sequence of the 8.4GHz maps shows a…
KELT-9b radial velocity curve
2019
In the framework of the GAPS project, we observed the planet-hosting star KELT-9 (A-type star, vsini~110km/s) with the HARPS-N spectrograph at the Telescopio Nazionale Galileo. In this work we analyse the spectra and the extracted radial velocities, to constrain the physical parameters of the system and to detect the planetary atmosphere of KELT-9b. We extracted from the high-resolution optical spectra the mean stellar line profiles with an analysis based on the Least Square Deconvolution technique. Then, we computed the stellar radial velocities with a method optimized for fast rotators, by fitting the mean stellar line profile with a purely rotational profile instead of using a Gaussian f…
ESPRESSO radial velocities of HE0107-5240
2020
The vast majority of the known stars of ultra low metallicity ([Fe/H]<-4.5) are known to be enhanced in carbon, and belong to the 'low-carbon band' (A(C)=log(C/H)+12~7.6). It is generally, although not universally, accepted that this peculiar chemical composition reflects the chemical composition of the gas cloud out of which these stars were formed. The first ultra-metal-poor star discovered, HE 0107-5240, is also enhanced in carbon and belongs to the 'low-carbon band'. It has recently been claimed to be a long-period binary, based on radial velocity measurements. It has also been claimed that this binarity may explain its peculiar composition as being due to mass transfer to a former AGB …
Post-AGB candidates in LMC and SMC SALT spectra
2020
We selected a sample of post-AGB candidates in the Magellanic Clouds on the basis of their near- and mid-infrared colour characteristics. Fifteen of the most optically bright post-AGB candidates were observed with the South African Large Telescope in order to determine their stellar parameters and thus to validate or discriminate their nature as post-AGB objects in the Magellanic Clouds. The spectral types of absorption-line objects were estimated according to the MK classification, and effective temperatures were obtained by means of stellar atmosphere modelling. Emission-line objects were classified on the basis of the fluxes of the emission lines and the presence of the continuum. Out of…
Kuinka yhdistää opiskelu työhön ja perhe-elämään? : ohjauksen merkitys aikuisopiskelijan moniulotteisella elämänkentällä
2018
Tutkimuksen tavoitteena oli selvittää, minkälaiseksi tutkimukseen osallistuneet aikuisopiskelijat kokevat elämäntilanteensa, jossa yhdistyvät työ, opiskelu sekä perhe-elämän vaatimukset. Tämän lisäksi tarkoituksena oli tarkastella, minkälaisia merkityksiä aikuisopiskelijat antavat ohjaukselle senhetkisessä elämäntilanteessaan. Tutkimus kuuluu laadullisen tutkimuksen perinteeseen ja sen on otteeltaan fenomenologinen. Tutkimusaineisto on kerätty haastattelemalla yhtätoista aikuisopiskelijaa, joilla kaikilla on ollut henkilökohtainen ja tuore kokemus työn, perheen ja opiskelun yhteensovittamisesta. Haastattelun tukena käytettiin puolistrukturoitua haastattelurunkoa. Tutkimusaineisto on analyso…
Pomoc społeczna a jakość życia osób starszych
2013
Postęp cywilizacji oraz towarzyszące mu procesy nie tylko przyczyniają się do wydłużenia życia ludzkiego, ale także ujawniają niedomagania związane z koniecznością opieki nad ludźmi w okresie późnej adolescencji. Starzenie się jest naturalnym procesem w życiu każdego człowieka związanym nie tylko ze zmianami fizjologicznymi, które zachodzą w jego organizmie, ale także psychicznymi i społecznymi. Zwiększająca się liczba osób starszych wymusza potrzebę zapewnienia im właściwej opieki i dbałości o odpowiedni poziom jakości ich społecznego funkcjonowania. Niestety nie wszyscy z nich mogą korzystać z dobrej opieki rodzinnej. Dlatego też zadanie to musi przejąć państwo, którego obowiązkiem jest d…
Dzīves kvalitāte onkoloģiskiem pacientiem staru terapijas laikā
2019
Bakalaura darba tēma - “Dzīves kvalitāte onkoloģiskiem pacientiem staru terapijas laikā”. Tēma aktuāla, jo pacientiem staru terapijas laikā būtiski pasliktinās dzīves kvalitāte. Pētījuma mērķis: noskaidrot pacientu dzīves kvalitāti ietekmējošos faktorus staru terapijas laikā. Pētījuma hipotēze: onkoloģiskiem pacientiem staru terapijas laikā pasliktinās dzīves kvalitāte. Pētījumā tika izmantota kvantitatīvā pētījuma metode, pētījuma instruments - anketa. Pētījuma dalībnieki: 100 staru terapijas klīnikas pacienti. Pētījuma bāze: viena no Latvijas klīnikām. Pētījumā izvirzītā hipotēze apstiprinājās, jo pētījuma laikā tika noskaidroti faktori, kas ietekmē pacientu dzīves kvalitāti staru terapij…