Variable stars in the instability strip and on the giant branch  Page description

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Details of project

  
Identifier
42509
Type K
Principal investigator Szatmáry, Károly
Title in Hungarian Változócsillagok az instabilitási sávban és az óriás ágon
Title in English Variable stars in the instability strip and on the giant branch
Panel Physics 1
Department or equivalent Department of Experimental Physics (University of Szeged)
Participants Csák, Balázs
Derekas, Alíz
Fűrész, Gábor
Kiss L., László
Szabó M., Gyula
Vinkó, József
Starting date 2003-01-01
Closing date 2007-06-30
Funding (in million HUF) 13.180
FTE (full time equivalent) 0.00
state closed project





 

Final report

  
Results in Hungarian
Fő célunk pulzáló változócsillagok vizsgálata volt. Fotometriai és spektroszkópiai méréseket végeztünk hazai és külföldi műszerekkel, valamint felhasználtunk nemzetközi adatbázisokat. A delta Scuti és az RR Lyrae típusú csillagok esetében főleg a periódusváltozást elemeztük. A több rezgési módusban pulzáló beat-cefeidák kémiai összetételét, fémtartalmát határoztuk meg és a pulzáció és a fémtartalom közti összefüggést a pulzációs modellek tesztelésével. A félszabályos változócsillagok fénygörbéit a Fourier-analízis mellett idő-frekvencia módszerrel vizsgáltuk. Számos csillagnál kimutattuk, hogy a megfigyelt frekvenciaváltozás a pulzációs fázis sztochasztikus változásának eredménye, melyet a konvekció okoz. Több ezer vörös óriáscsillag periódus-fényesség relációjának eloszlását magyaráztuk meg, különös tekintettel az ellipszoidális változókra és a hosszú másodperiódust mutató csillagokra. Nyílt- és gömbhalmazokban sok változócsillagot fedeztünk fel. Csillagaik színképi elemzése alapján a halmazokra fémességet, kort, sebességeloszlást és dinamikai jellemzőket határoztunk meg. Kutatásaink kiterjedtek extragalaktikus szupernóvák, kettőscsillagok, kisbolygók vizsgálatára is, valamint exoholdak kimutatásának lehetőségeire. Kutatásaink széleskörű hazai és nemzetközi együttműködések keretében valósultak meg. A pályázat számával 35 folyóiratcikket és 18 konferencia anyagot publikáltunk, 150,459 impakt faktorral. Ezekre eddig 43 független hivatkozás történt.
Results in English
The main aim of our research was to study pulsating variable stars. We have carried out photometric and spectroscopic measurements at Hungarian and foreign observatories. We have used international databases. In the case of delta Scuti- and RR Lyrae-stars, we have examined mainly their period variations. We have determined the iron abundances of beat-Cepheids and tested the theoretical models via the dependence of pulsation on metal abundance. The light curves of semiregular variable stars were studied with Fourier- and time-frequency methods. We have pointed out stochastic variation of the pulsational phase in many stars, which is caused by convective motions. We have investigated the explanations of the distribution of red giant stars on the period-luminosity diagram, with particular attention on ellipsoidal variables and stars with long secondary period. We have discovered many new variable stars in open- and globular clusters. From spectroscopic measurements we have determined metallicity, age, velocity distribution and dynamical properties of these clusters. We extended our research to the study of binary stars, minor planets, extragalactic supernovae and the possibilities of discovering exomoons. Our research has been carried out with broad national- and international collaborations. During the project we have published 35 papers in refereed journals and 18 conference proceedings. The impact factor is 150.459. We have received 43 independent citations.
Full text http://real.mtak.hu/636/
Decision
Yes





 

List of publications

  
Csák B; Kiss LL; Retter A; Jacob A; Kaspi S: Spectroscopic monitoring of the transition phase in nova V4745 Sgr, Astronomy and Astrophysics, 429: 599-605, 2004
Balog Z; Kenyon SJ; Lada EA; Barsony M; Vinkó J; Gáspár A: A near-infrared (JHK) survey of the vicinity of the HII region NGC 7538: Evidence for a young embedded cluster, Astronomical Journal 128: 2942-2953, 2004
Derekas A; Kiss LL; Udalski A; Bedding T R; Szatmáry K: A first-overtone RR Lyrae star with cyclic period changes, poster on Annual Scientific and General Meeting of the ASA, University of Queensland, 4-8 July 2004, Australia, 2004
Székely P; Kiss LL; Szabó GyM; Sárneczky K; Csák B; Váradi M; Mészáros Sz: CCD photometry of 23 minor planets, Planetary and Space Science 53: 925-936, 2005
Kiss LL; Bedding, TR: Photometric biases due to stellar blending: implications for measuring distances, constraining binarity and detecting exoplanetary transits, Monthly Notices of Royal Astron. Soc. 358: 883-891, 2005
Gáspár A ; Balog Z; Makai Z; Vinkó J; Kenyon SJ: Preliminary results on newly discovered embedded clusters, in: Proc. of „Cores to Clusters'', Porto, Portugal, 6-9 Oct, 2004, ASSL 324: 209-214, 2005
Lindstrom C; Griffin J; Kiss LL; Uemura M; Derekas A; Mészáros Sz; Székely P: New clues on outburst mechanisms and improved spectroscopic elements of the black-hole binary V4641 Sagittarii, Monthly Notices of Royal Astron. Soc. 363: 882-890, 2005
Székely P; Kiss LL; Csák B; Derekas A; Bedding TR; Szatmáry K: A comprehensive survey of variable stars in the globular cluster NGC 362, in proc. ''Stellar pulsation and evolution'', Mem. S. A. It., 77: 346-347, 2006
Szabó GyM; Fűrész G; Székely P; Szentgyorgyi AH: Kinematics and variable stars in NGC 1907 and 1912, in: Proc. PhD Conf. "Astrophysics of Variable Stars", Pécs, Hungary, 5-10 Sept 2005, Eds. C. Sterken and C. Aerts, ASP Conf. Series, 349: 339-342, 2006
Derekas A; Kiss LL; Csák B; Griffin J; Lindstrom C; Mészáros Sz; Székely P; Ashley MCB; Bedding TR: Binarity and multiperiodicity in high-amplitude delta Scuti stars, in proc. ''Stellar pulsation and evolution'', Mem. S. A. It., 77: 517-518, 2006
Szabó GyM; Szatmáry K; Simon A; Divéki Zs: Light curve effects due to ''exomoons'' in exoplanetary transits, poster on PhD Conf. ''Astrophysics of Variable Stars'', Pécs, Hungary, 5-10 Sept 2005, 2005
Sziládi K; Vinkó J; Poretti E; Szabados L; Kun M: Echelle spectroscopy of double-mode Cepheids, in: Proc. PhD Conf. ''Astrophysics of Variable Stars'', Pécs, Hungary, 5-10 Sept 2005, Eds. C. Sterken and C. Aerts, ASP Conf. Series, 349: 347-350, 2006
Borkovits T; Elkhateeb MM; Csizmadia Sz; Nuspl J; Bíró IB; Hegedüs T; Csorvási R: Indirect evidence for short period magnetic cycles in W UMa stars – Period analysis of five overcontact systems, Astronomy and Astrophysics, 441: 1087-1097, 2005
Szabó GyM; Szatmáry K; Divéki Zs; Simon A: Possibility of a photometric detection of ''exomoons'', Astronomy and Astrophysics 450: 395-398, 2006
Kun M; Nikolic S; Johansson LEB; Balog Z; Gáspár A: Low-mass star formation in Lynds 1333, Monthly Notices of Royal Astron. Soc. 371: 732-738, 2006
Balog Z; Rieke GH; Su KYL; Muzerolle J; Young ET: Spitzer MIPS 24 micron detection of photoevaporating protoplanetary disks, Astrophysical Journal 650: L83-L86, 2006
Takáts K; Vinkó J: Distance estimate and progenitor characteristics of SN 2005cs in M51, Monthly Notices of Royal Astron. Soc. 372: 1735-1740, 2006
Vinkó J; Takáts K; Sárneczky K; Szabó GyM; Mészáros Sz; Csorvási R; Szalai T; Gáspár A; Pál A; Csizmadia Sz; Kóspál A; Rácz M; Kun M; Csák B; Fûrész G; DeBond H; Grunhut J; Thomson J; Mochnacki S: The first year of SN 2004dj in NGC 2403, Monthly Notices of Royal Astron. Soc. 369: 1780-1796, 2006
Szabó Gy; Milani G; Vinante C; Ligustri R; Sostero G; Trabatti R: Project CARA: A database of coordinated observations of bright comets, in: Proc. "Exploration ofAsteroids and Comets in the 21th Century", Hegyhátsál, Hungary, 2006, Ed. Tuboly Vince, 57-81., 2006
Milani GA; Szabó GyM; Sostero G; Trabatti R; Ligustri R; Nicolini M; Facchini M; Tirelli D; Carosati D; Vinante C; Higgins D: Photometry of comet 9P/Tempel 1 during the 2004/2005 approach and the Deep Impact module impact, Icarus 187: 276-284, 2007
Bouvier J; Alencar SHP; Boutelier T; Dougados C; Balog Z; Grankin K; Hodgkin ST; Ibrahimov MA; Kun M; Magakian TYu; Pinte C: Magnetospheric accretion-ejection processes in the classical T Tauri star AA Tau, Astronomy and Astrophysics 463: 1017-1028, 2007
Szalai T; Kiss LL; Mészáros Sz; Vinkó J; Csizmadia Sz: Physical parameters and multiplicity of five southern close eclipsing binaries, Astronomy and Astrophysics 465: 943-952, 2007
Balog Z; Muzerolle J; Rieke GH; Su KYL; Young ET; Megeath ST: Spitzer/IRAC-MIPS survey of NGC2244: protostellar disk survival in the vicinity of hot stars, Astrophysical Journal 660: 1532-1540, 2007
Currie T; Balog Z; Kenyon SJ; Rieke G; Prato L; Young ET; Muzerolle J; Clemens DP; Buie M; Sarcia D; Grabu A; Tollestrup EV; Taylor B; Dunham E; Mace G: Spitzer/IRAC and JHKs observations of h & chi Persei: constraints on protoplanetary disk and massive cluster evolution at ~ 10^7 yr, Astrophysical Journal 659: 599-615, 2007
Borkovits T; Csizmadia Sz; Nuspl J; Bíró IB: Indirect evidence for short period magnetic cycles in overcontact binary stars, in: Proc. "4th Workshop of Young Researchers in Astronomy & Astrophysics"; Budapest, Hungary, 11-13 January, 2006, Ed. E. Forgács-Dajka, PADEU vol. 17: 109-114, 2006
Székely P; Jackson R; Kiss LL; Szatmáry K: A survey of variable stars in the globular cluster NGC 362, in: Proc. ''4th Workshop of Young Researchers in Astronomy & Astrophysics''; Budapest, Hungary, 11-13 January, 2006, Ed. E. Forgács-Dajka, PADEU vol. 17: 127-132, 2006
Sipos N; Vinkó J: Interstellar reddening of type Ia supernovae, in: Proc. ''4th Workshop of Young Researchers in Astronomy & Astrophysics''; Budapest, Hungary, 11-13 January, 2006, Ed. E. Forgács-Dajka, PADEU vol. 17: 195-202, 2006
Dupree AK; Avrett EH; Brickhouse NS; Cranmer SR; Szalai T: The structured chromosphere and wind of TW Hya, in: Proc. "Cool Stars, Stellar Systems and the Sun: CS 14", ASP Conference Series, vol. xxx, Ed. Gerard van Belle, in press, 2007
Szabó MGy; Ivezic Z; Juric M; Lupton R: The properties of Jovian Trojan asteroids listed in SDSS Moving Object Catalogue 3, Monthly Notices of Royal Astron. Soc. 377: 1393-1406, 2007
Székely P; Kiss LL; Szatmáry K; Csák B; Bakos GÁ; Bedding TR: Radial velocities of five globular clusters obtained with AAOmega, Astronomische Nachrichten 328: Issue 8, in press, 2007
Kiss LL; Székely P; Bedding TR; Bakos GÁ; Lewis GF: A wide-field kinematic survey for tidal tails around five globular clusters, Astrophysical Journal Letters 659: L129-L132, 2007
Currie T; Kenyon SJ; Rieke G; Balog Z; Bromley BC: Terrestrial zone debris disk candidates in h & chi Persei, Astrophysical Journal Letters 663: L105-L108, 2007
Simon A; Szatmáry K; Szabó MGy: Determination of the size, mass, and density of ''exomoons'' from photometric transit timing variations, Astronomy and Astrophysics 470: 727-731, 2007
Sziládi K; Vinkó J; Poretti E; Szabados L; Kun M: New homogeneous iron abundances of double-mode Cepheids from high-resolution echelle spectroscopy, Astronomy and Astrophysics in press, 2007
Keresztes Z; Gergely ÁL; Nagy B; Szabó MGy: The luminosity-redshift relation in brane-worlds I. Analytical results, PMC Physics A submitted, 2007
Szabó MGy; Gergely ÁL; Keresztes Z: The luminosity-redshift relation in brane-worlds: II. Confrontation with experimental data, PMC Physics A submitted, 2007
Szabó MGy: Nagy égboltfelmérések a csillagászatban, Fizikai Szemle 56: No.12. 403-407, 2006
Acosta-Pulido JA; Kun M; Ábrahám P; Kóspál Á; Csizmadia Sz; Kiss LL; Moór A; Szabados L; Benkő JM; Barrena DR; Charcos-L M; Eredics M; Kiss ZT; Manchado A; Rácz M; Ramos-A C; Székely P; Vidal-Nunez MJ: The 2004-2006 outburst and environment of V1647 Ori, Astronomical Journal 133: 2020-2036, 2007
Jurkovic M; Vinkó J: Mapping atmospheric motions in classical and type II Cepheids, in: Proc. "Precision Spectroscopy in Astrophysics", Sept 11-15, 2006, Aveiro, Portugal, in press, 2007
Sziládi K; Vinkó J; Szabados L; Kun M; Poretti E: Iron abundances of southern double-mode Cepheids from high-resolution echelle spectroscopy, in: Proc. "Precision Spectroscopy in Astrophysics", Sept 11-15, 2006, Aveiro, Portugal, in press, 2007
Vinkó J; Takáts K: The Expanding Photosphere Method: progress and problems, in: AIP Conf. Proc. "Supernova 1987A: 20 Years After-Supernovae and Gamma-Ray Bursters", Febr 19-23, 2007, in press, 2007
Martí-Vidal I; Marcaide JM; Alberdi A; Guirado JC; Lara L; Perez-Torres MA; Ros E; Argo MK; Beswick RJ; Muxlow TWB; Pedlar A; Shapiro II; Stockdale CJ; Sramek RA; Weiler KW; Vinkó J: 8.4 GHz VLBI observations of SN2004et in NGC 6946, Astronomy and Astrophysics, 470: 1071-1078, 2007
Szakáts R; Szabó MGy; Szatmáry K: Does the O-C of BE Lyncis really vary?, Information Bulletin on Variable Stars, submitted, 2007
Derekas A; Kiss LL; Székely P; Alfaro EJ; Csák B; Mészáros Sz; Rodríguez E; Rolland A; Sárneczky K; Szabó GyM; Szatmáry K; Váradi M; Kiss Cs: A photometric monitoring of bright high-amplitude delta Scuti stars. II. Period update for seven stars, Astronomy and Astrophysics 402: 733-743, 2003
Derekas A; Kiss LL; Udalski A; Bedding TR; Szatmáry K: A first-overtone RR Lyrae star with cyclic period changes, Monthly Notices of Royal Astron. Soc. 354: 821-826, 2004
Szatmáry K: Period-radius relation for semiregular and Mira stars, In: New Deal in European Astronomy: Trends and Perspectives JENAM 2003, Budapest, Hungary, 25-30 Aug, Abstract Book p. 180; Communication in Astroseismology 145: p.58, 2004
Lah P; Kiss LL; Bedding TR: Red variables in the OGLE-II data base - III. Constraints on the three-dimensional structures of the LMC and SMC, Monthly Notices of Royal Astron. Soc. 359: L42-L46, 2005
Derekas A; Kiss LL; Bedding TR; Kjeldsen H; Lah P; Szabó MGy: Ellipsoidal variability and Long Secondary Periods in MACHO red giant stars, Astrophysical Journal 650: L55-L58, 2006
Kiss LL; Szabó MGy; Bedding TR: Variability in red supergiant stars: pulsations, long secondary periods and convection noise, Monthly Notices of Royal Astron. Soc. 372: 1721-1734, 2006
Jurkovic M; Szabados L; Vinkó J; Csák B: Pulsation and orbit of AU Pegasi, Astronomische Nachrichten 328: Issue 8, in press, 2007
Kiss LL; Derekas A; Szabó GyM; Bedding TR; Szabados L: Defining the instability strip of pulsating post-AGB binary stars from ASAS and NSVS photometry, Monthly Notices of Royal Astron. Soc. 375: 1338-1348, 2007
Szabados L; Kiss LL; Derekas A: The anomalous Cepheid XZ Ceti, Astronomy and Astrophysics 461: 613-618, 2007
Székely P; Kiss LL; Jackson R; Derekas A; Csák B; Szatmáry K: RR Lyrae stars in the southern globular cluster NGC 362, Astronomy and Astrophysics 463: 589-600, 2007



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