Matches in SemOpenAlex for { <https://semopenalex.org/work/W1520397844> ?p ?o ?g. }
Showing items 1 to 68 of
68
with 100 items per page.
- W1520397844 abstract "Radial velocity variations have revealed planets orbiting 51 Peg, 47 UMa, and 70 Vir, and a low-mass companion orbiting HD 114762. We analyze parallel records of photometric measurements in Stro mgren b and y and Johnson V , R, and I passbands and Ca II H and K Nuxes in those stars. In the case of 51 Peg, the high precision of the di†erential photometric measurements made by the 0.75 m Automatic Photoelectric Telescope and the nonvariability of the star would allow the detection of a transit of a planet as small as Earth (corresponding to an amplitude of 0.0001 mag) if its orbit were nearly coplanar with our line of sight. No transits were observed. For 51 Peg and 70 Vir, the upper limit of nondetection of photometric variability at their companionIs orbital periods is *(b ] y)/2 0.0002^ 0.0002 mag. For HD 114762, it is *V 0.0007^ 0.0004 mag. Such small amplitudes of photometric variability seem to eliminate periodic velocity variations expected from p-mode oscillations. All four stars are magnetically quiet ; that is, they lack the typical Ca II and photometric variability due to rotation and activity cycles expected from surface magnetic activity in solar-type stars. Such quiescence produces an interesting observational bias that favors the detection of planets from lowamplitude radial velocity or photometric variations by minimizing the contribution from intrinsic stellar variability. We discuss the circumstances for which the probability of planet detections is improved by the reduced level of variability from surface magnetic activity in G and K stars. Stars with low variability in surface activity should be the best candidates for planet searches using radial velocity and photometric techniques. Searches for planets around younger, more active stars will be impeded by variations in velocity or brightness caused by time-varying surface features. The Ca II H and K Nuxes indicate that all four stars are older than 5 Gyr. Ages were estimated from the average levels of Ca II H and K Nuxes and an existing relationship of the decrease of Ca II Nuxes with age on the lower main sequence and were drawn from previous results based on theoretical isochrone Ðtting. Values of the projected rotational velocity, v sin i, are determined for 70 Vir and 47 UMa from high-resolution spectra. Subject headings : planetary systems E stars : activity E stars : fundamental parameters" @default.
- W1520397844 created "2016-06-24" @default.
- W1520397844 creator A5010036871 @default.
- W1520397844 creator A5040631460 @default.
- W1520397844 creator A5060483018 @default.
- W1520397844 creator A5079439837 @default.
- W1520397844 creator A5091785575 @default.
- W1520397844 date "1997-01-01" @default.
- W1520397844 modified "2023-09-26" @default.
- W1520397844 title "PROPERTIES OF SUN-LIKE STARS WITH PLANETS: 51 PEGASI," @default.
- W1520397844 cites W3126617538 @default.
- W1520397844 hasPublicationYear "1997" @default.
- W1520397844 type Work @default.
- W1520397844 sameAs 1520397844 @default.
- W1520397844 citedByCount "2" @default.
- W1520397844 crossrefType "journal-article" @default.
- W1520397844 hasAuthorship W1520397844A5010036871 @default.
- W1520397844 hasAuthorship W1520397844A5040631460 @default.
- W1520397844 hasAuthorship W1520397844A5060483018 @default.
- W1520397844 hasAuthorship W1520397844A5079439837 @default.
- W1520397844 hasAuthorship W1520397844A5091785575 @default.
- W1520397844 hasConcept C121332964 @default.
- W1520397844 hasConcept C1276947 @default.
- W1520397844 hasConcept C150846664 @default.
- W1520397844 hasConcept C163479331 @default.
- W1520397844 hasConcept C180205008 @default.
- W1520397844 hasConcept C41074950 @default.
- W1520397844 hasConcept C44870925 @default.
- W1520397844 hasConcept C51244244 @default.
- W1520397844 hasConcept C62520636 @default.
- W1520397844 hasConcept C88991977 @default.
- W1520397844 hasConceptScore W1520397844C121332964 @default.
- W1520397844 hasConceptScore W1520397844C1276947 @default.
- W1520397844 hasConceptScore W1520397844C150846664 @default.
- W1520397844 hasConceptScore W1520397844C163479331 @default.
- W1520397844 hasConceptScore W1520397844C180205008 @default.
- W1520397844 hasConceptScore W1520397844C41074950 @default.
- W1520397844 hasConceptScore W1520397844C44870925 @default.
- W1520397844 hasConceptScore W1520397844C51244244 @default.
- W1520397844 hasConceptScore W1520397844C62520636 @default.
- W1520397844 hasConceptScore W1520397844C88991977 @default.
- W1520397844 hasLocation W15203978441 @default.
- W1520397844 hasOpenAccess W1520397844 @default.
- W1520397844 hasPrimaryLocation W15203978441 @default.
- W1520397844 hasRelatedWork W1488134468 @default.
- W1520397844 hasRelatedWork W1493610423 @default.
- W1520397844 hasRelatedWork W1667303067 @default.
- W1520397844 hasRelatedWork W1896068817 @default.
- W1520397844 hasRelatedWork W2018079349 @default.
- W1520397844 hasRelatedWork W2071635107 @default.
- W1520397844 hasRelatedWork W2077882082 @default.
- W1520397844 hasRelatedWork W2083772753 @default.
- W1520397844 hasRelatedWork W2106608774 @default.
- W1520397844 hasRelatedWork W2124811945 @default.
- W1520397844 hasRelatedWork W2133379767 @default.
- W1520397844 hasRelatedWork W2134934397 @default.
- W1520397844 hasRelatedWork W2507271022 @default.
- W1520397844 hasRelatedWork W2796918883 @default.
- W1520397844 hasRelatedWork W3087596849 @default.
- W1520397844 hasRelatedWork W3093537643 @default.
- W1520397844 hasRelatedWork W3098766152 @default.
- W1520397844 hasRelatedWork W3101571777 @default.
- W1520397844 hasRelatedWork W3102269881 @default.
- W1520397844 hasRelatedWork W3169765395 @default.
- W1520397844 isParatext "false" @default.
- W1520397844 isRetracted "false" @default.
- W1520397844 magId "1520397844" @default.
- W1520397844 workType "article" @default.