Photometric and Spectroscopic Analysis of Five Am Stars
The photometric analysis of sample Am stars is carried out to determine the stellar characteristics and to constrain the stellar dynamics. The spectroscopic analysis of the studied Am stars confirms their general characteristics of Am stars. The available data on elemental abundances for HD 113878 and HD 118660 have shown different characteristics during different epochs of observations. The basic stellar parameters (mass, luminosity, radius, life time, distance, proper-motion, etc.) are also determined to identify the stellar habitat zones for earth like exoplanet. Such information is important to identify suitable planets for human settlement in the near future. In this connection, the tidal radius and boundaries of the habitable zone of each star have been computed to support the search of an extra-terrestrial life around them. Asteroseismic mass scale test shows greater stellar masses comparable to the solar mass.
Astronomy: Photometric Methods, Database, Astronomical Reduction, HD 73045, HD 98851, HD 113878, HD 118660, HD 207561
[1]
Budaj, J. & Ilive, I. Kh.: Abundance analysis of Am binaries and search for tidally driven abundance anomalies-I. HD 33254, HD 178449 and HD 198391. Mon. Not. R. Astron. Soc. 346, 27 (2003).
[2]
Vauclair, S.: Variable Stars in the Local Group, eds. D. W. Kurtz, K. R. Pollard (San Francisco: ASP). ASP Conf. Series (ASPC), 310, 413 (2004).
[3]
Ryabchikova, T., Ryabtsev, A., Kochukhov, O., & Bagnulo, S.: Rare-earth elements in the atmosphere of the magnetic chemically peculiar star HD 144897- New Classification of the Nd III spectrum. Astron. Astrophys. 456, 329 (2006).
[4]
Gray, R. O. & Corbally, C. J.: Stellar Spectral Classification. Princeton University Press, 2009. ISBN: A978-0-691-12511-4.
[5]
Balona, L. A., Ripepi, V., Catanzaro, G., Kurtz, D. W., Smalley, B. et al.: Kepler observations of Am stars. Mon. Not. R. Astron. Soc. 414, 792 (2011).
[6]
Joshi, S., Semenko, E., Moiseeva, A., Joshi, Gireesh C., Joshi, Y. C. & Sachkov, M.: Photometric and Spectroscopic Analysis of CP Stars under Indo-Russian Collaboration. Physics and Evolution of Magnetic and related stars, ASP Conference Series, 494, 210 (2015).
[7]
Kraus, A. L. & Hillenbrand, L. A.: The stellar population of Praesepe and Coma Berenices. Astron. J. 134, 2340 (2007).
[8]
Bertaud, C.: Catalogue et bibliographie des etoiles A a spectre particulier. Journal des Observateurs, 43, 129 (1960).
[9]
Bidelman, W. P.: Spectral Classification of the Brighter stars of the Praesepe Cluster. Publications of the Astronomical Society of the Pacific, 68, No. 403, 318 (1956).
[10]
Fossati, L., Bagnulo, S., Landstreet J., Wade G., Kochukhov O., Monier, R., Weiss, W. & Gebran, M.: The effect of rotation on the abundances of the chemical elements of the A-type stars in the Praesepe cluster. Astron. Astrophys. 483, 891 (2008).
[11]
Fossati, L., Bagnulo, S., Monier R., Khan S. A., Kochukhov, O., Landstreet, J., Wade G. & Weiss, W.: Late stages of the evolution of A-type stars on the main sequence: comparison between observed chemical abundances and diffusion models for 8 Am Stars of the Praesepe cluster, Astron. Astrophys. 476, 911 (2007).
[12]
Hui-Bon-Hoa, A., Burkhart, C. & Alecian, G.: Metal abundances of A-type stars in three galactic clusters. Astron. Astrophys. 323, 901 (1997).
[13]
Masana, E., Jordi, C. & Ribas, I.: Effective temperature scale and bolometric corrections from 2MASS photometry. Astron. Astrophys. 450, 735 (2006).
[14]
Pourbaix, D., Tokovinin, A. A., Batten, A. H., Fekel, F. C., Hartkope, W. I., Levato, H., Morrell, N. I., Torres, G. and Udry, S.: SB9: The ninth catalogue of spectroscopic binary orbits. Astron. Astrophys. 424, 727 (2004).
[15]
Duflot, M., Figon, P. & Meyssonnier, N.: Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Radial velocities: The wilson-Evans-Batten catalogue. Astron. Astrophys. Suppl. Ser. 114, 269 (1995).
[16]
Dickens, R. J., Kraft, R. P. & Krzeminski, W.: Effect of rotation on the colors and magnitudes of stars in Praesepe. Astron. J. 73, 6 (1968).
[17]
Wilson, R. E.: General Catalogue of Stellar Radial Velocities. 1953GCRV. C.....0W.
[18]
Wilson, R. E. & Joy, A.: Radial velocities of 2111 stars. Astrophys. J. 111, 221 (1950).
[19]
Olsen, E. H.: Estimation of spectral classifications for bright northern stars with interesting Stromgren indices. Astron. Astrophys. Suppl. Ser. 39, 205 (1980).
[20]
Abt, H. A.: Spectroscopic tests of photoelectric stellar classification of abnormal stars. Astrophys. J. 285, 247 (1984).
[21]
Gontcharov, G. A.: Pulkovo Compilation of Radial Velocities for 35 495 Happarcos stars in a common system. Astronomy Letters, 32 (11), 759 (2006).
[22]
Grenier, S., Baylac, M. O., Rolland, L., Burnage, R., Arenou, F., Briot, D. et al.: Radial velocities. Measurement of 2800 B2-F5 stars for HIPPARCOS. Astron. Astrophys. Suppl. Ser. 137, 451 (1999).
[23]
Luyten, W. J.: IAU Colloquium 7, Ed. Luyten W. J., 1970, Minneapolis, 7, 153 (1971).
[24]
Joshi S., Girish V., Sager R., Kurtz D. W., Martinez P., Kumar B., Seetha S., Ashoka B. N. & Zhou A.: Discovery of unusual pulsations in the cool, evolved Am stars HD 98851 and HD 102480. Mon. Not. R. Astron. Soc. 344, 431 (2003).
[25]
Joshi S., Mary D. L., Martinez P., Kurtz D. W., Girish V., Seetha S., Sagar R. and Ashoka B. N.: The Nainital-Cape Survey II: Report for pulsation in five chemically peculiar A-type stars and presentation of 140 null results. Astron. Astrophys. 450, 763 (2006).
[26]
Casagrande L., Schoenrich, R., Asplund M., Cassisi, S., Ramirez, I., Melendez, J., Bensby, T. & Feltzing, S.:. Astron. Astrophys. 530A, 138 (2011).
[27]
Bailer-Jones, C. A. L.: Bayesian inference of stellar parameters and interstellar extinction using parallaxes and multiband photometry. Mon. Not. R. Astron. Soc. 411, 435 (2011).
[28]
Perryman, M. A. C, Lindergen, L., Kovalevsky, J., Hog, E., Bastian, U., et al.: The Hipparcos Catalogue. Astron. Astrophys. 323, L49 (1997), reprint in Astron. Astrophys. 500, 500 (2009).
[29]
Van Leeuwen, F.: Validation of the new Hipparcos reduction. Astron. Astrophys. 464 (2), 653 (2007).
[30]
Barry, D. C.: Spectral classification of A & F stars. Astrophys. J. Suppl. Ser. 19, 281 (1970).
[31]
Appenzeller, I.: MK spectral types for 185 bright stars. Publ. Astron. Soc. Pac. 79, 102 (1967).
[32]
Harper W. E.: The radial velocities of 917 stars. Publ. Dominion Astrophys. Obs., 7, 1-97 (1937).
[33]
Cowley, A. P. & Cowley, R. C.: Slit spectra of some peculiar and metallic-line A stars. Publ. Astron. Soc. Pac. 77, 184 (1965).
[34]
Floquet, M.: Classification spectrale d’etoiles Ap et Am. Astron. Astrophys. Suppl. Ser. 21, 25 (1975).
[35]
Cunha M. S.: A theoretical instability strip for rapidly oscillating Ap stars. Mon. Not. R. Astron. Soc. 333, 47 (2002).
[36]
Joshi, S., Semenko, E., Martinez P., Sachkov, M., Joshi, Y. C., Seetha, S., Chakradhari, N. K., Mary D. L., Girish, V. & Ashoka, B. N.: A spectroscopic analysis of the chemically peculiar star HD 207561 Mon. Not. R. Astron. Soc. 424, 2002 (2012).
[37]
Catanzaro, G. & Ripepi, V.: Fundamental parameters of eight Am stars: comparing observations with theory. Mon. Not. R. Astron. Soc. 441, 1669 (2014).
[38]
Gratton R. G. et al.: SARG: the high-resolution spectrograph of TNG. Exp. Astron., 12, 107 (2001).
[39]
Joshi, S., Semenko, E., Moiseeva, A., Sharma, K., Joshi, Y. C., Sachkov, M., Singh, H. P. & Yerra, B. K.: High-resolution spectroscopy and spectropolarimetry of selected δ Sct pulsating variables. Mon. Not. R. Astron. Soc. 467, 633 (2017).
[40]
Balona, L. A.: Calibration of effective temperature, bolometric correction and mass for early-type stars using Stroemgren photometric indices. Mon. Not. R. Astron. Soc. 211, 973 (1984).
[41]
Moon T. T. & Dworetsky M. M.: Grids for the determination of effective temperature and surface gravity of B, A and F stars using ubvy-beta photometry. Mon. Not. R. Astron. Soc. 217, 305 (1985).
[42]
Moon T. T. & Dworetsky M. M.: Stromgren’s (a, r) method for calculating MV. The Observatory, 104, 273 (1984).
[43]
Napiwotzki R., Schoenberner D., & Wenske V.: On the determination of effective temperature and surface gravity of B, A and F stars using Stromgren uvbyβ photometry. Astron. Astrophys. 268, 653 (1993).
[44]
Stromgren B.: Spectral Classification Through Photoelectric Narrow-Band Photometry. Annu. Rev. Astron. Astrophys. 4, 433.
[45]
Grosbol P. J.: Space velocities and ages of nearby early-type stars. Astron. Astrophys. Suppl. Ser., 32, 409 (1978).
[46]
Savage B. D. & Mathis J. S.: Observed properties of interstellar dust. Annu. Rev. Astron. Astrophys. 17, 73 (1979).
[47]
Kochukhov O. P.: Spectrum synthesis for magnetic, chemically stratified stellar atmospheres. Romanyuk I. I., Curates D. O: eds, Proc. Int. Conf., Physics of Magnetic Stars. Special Astrophysical Observatory, Nizhnij Arkhyz of the Russian AS, p. 109-118 (2007).
[48]
Hundt E.: Microturbulence in Stellar Spectroscopy. Astron. Astrophys. 29, 17 (1973).
[49]
Asplund, M., Grevesse, N., Sauval, A. J. & Pat, S.: The Chemical Composition of the Sun. Annu. Rev. Astron. Astrophys. 47, 481, 2009.
[50]
Rouan D.: Effective Temperature. In: Gargaud M. et al. (eds) Encyclopedia of Astrobiology. Springer, Berlin, Heidelberg (2011).
[51]
McDonald, I., Zijlstra, A. A. and Boyer, M. L.: Fundamental parameters and infrared excesses of Hipparcos stars. Mon. Not. R. Astron. Soc. 427, 343 (2012).
[52]
Munoz B. J., Asensio R. A. & Allende P. C.: A PCA approach to stellar effective temperatures. Astron. Astrophys. 553, 95 (2013).
[53]
Joshi, S., Mary, D. L., Chakradhari, N. K., Tiwari, S. K & Billaud, C.: The Nainital-Cape Survey III. A search for pulsational variability in chemically peculiar stars. Astron. Astrophys. 507, 1763 (2009).
[54]
Zorec, J. & Royer, F.: Rotational velocities of A-type stars. IV. Evolution of rotational velocities. Astron. Astrophys. 537A, 120 (2012).
[55]
Cantiello M., Langer N., Brott I., de Koter A., Shore S. N., Vink J. S., Voegler A. & Yoon S.-C.: On the origin of micro-turbulence in hot stars. CoAst, 158, 61 (2009).
[56]
Gebran M., Monier R., Royer F., Lobel A. & Blomme R.: Proceeding of the International Conference, pp. 193-198 (2014) (Eds. Mathys et al.).
[57]
Smalley B.: Teff and log g determinations. Mem. S. A. It Suppl. 8, 130 (2005).
[58]
Frouard, J., Dorland, B. N., Makarov, V. V., Zacharias, N., Finch, C. T.: UrHip Proper Motion Catalogue. Astron. J. 150 (5), 141 (2015).
[59]
Roeser, S., Demleitner, M. & Schilbach, E.: The PPMXL Catalogue of positions and proper motions on the ICRS. Combining USNO−B1 and the Two Micron All Sky Survey (2MASS). Astron. J. 139, 2440 (2010).
[60]
Zacharias, N., Finch, C. T., Girard, T. M., Henden, A., Bartlett, J. L., Monet, D. G., & Zacharias, M. I.: The Fourth US Naval Observatory CCD Astrograph Catalog (UCAC4) Astron. J. 145, 44 (2013).
[61]
Eggl S., Pilat-Lohinger E., Funk B., Georgakarakos N. & Haghighipour N.: Circumstellar habitable zones of binary-star systems in the solar neighbourhood. Mon. Not. R. Astron. Soc. 428, 3104 (2013).
[62]
Kasting J. F., Whitmire D. P., Reynolds R. T.: Habitable Zones around Main Sequence Stars. Icarus, 101, 108 (1993).
[63]
Huang Su-Sh: Occurrence of Life in the Universe. American Scientist, 47 (3), 397 (1959).
[64]
Cruz M. & Coontz R.: Alien Worlds Galore. Science, 340 (6132): 565 (2013).
[65]
Whitmire D. P., Reynolds R. T.: In: Doyle, Laurence (ed.), Circumstellar Habitable Zones, 117-142. Travis House Publications, Menlo Park. (1996).
[66]
Neiner C. & Lampens P.: First discovery of a magnetic field in a main-sequence δ Scuti star: the Kepler star HD 188774. Mon. Not. R. Astron. Soc. 454, L86.
[67]
Turcotte S., Richer J., Michaud G., Christensen-Dalsgaard J.: The effect of diffusion on pulsation of stars on the upper main sequence. Astron. Astrophys. 360, 603 (2000).
[68]
van Saders, J. L. & Pinsonneault, M. H.: Fast star slow: old star, young star: subgaint rotational as a population and stellar physics diagnostic. Astrophys. J. 776, 67 (2013).
[69]
Kjeldsen, H. & Bedding, T. R.: Amplitude of stellar oscillations for asteroseismology. Astron. Astrophys. 293, 87 (1995).
