A slowly pulsating B-type star (SPB), formerly known as a 53 Persei variable, is a type of pulsating variable star. They may also be termed a long-period pulsating B star (LPB).[1] As the name implies, they are main-sequence stars of spectral type B2 to B9 (3 to 9 times as massive as the Sun) that pulsate with periods between approximately half a day and five days,[2] however within this most member stars have been found to have multiple periods of oscillations.[3] They display variability both in their light emission and in their spectral line profile. The variations in magnitude are generally smaller than 0.1 magnitudes,[2] making it quite hard to observe variability with the naked eye in most cases. The variability increases with decreasing wavelength,[3] thus they are more obviously variable in ultraviolet spectrum than visible light. Their pulsations are non-radial, that is, they vary in shape rather than volume; different parts of the star are expanding and contracting simultaneously.[4]
A visual bandlight curve for V469 Persei (53 Persei), plotted from data published by Huang et al. (1994). This star was the prototype for this class of variable stars.[5]
These stars were first identified as a group and named by astronomers Christoffel Waelkens and Fredy Rufener in 1985 while looking for and analysing variability in hot blue stars. Improvements in photometry had made finding smaller changes in magnitude easier, and they had found that a high percentage of hot stars were intrinsically variable. They referred to them as 53 Persei stars after the prototype 53 Persei.[6] Ten had been discovered by 1993, though Waelkens was unsure if the prototype was actually a member and recommended referring to the group as slowly pulsating B (SPB) stars.[3] The General Catalogue of Variable Stars uses the acronym LPB for "comparatively long-period pulsating B stars (periods exceeding one day)",[7] although this terminology is rarely seen elsewhere.[8]
The following list contains selected slowly pulsating B-type stars that are of interest to amateur or professional astronomy. Unless otherwise noted, the given magnitudes are in the V-band.
^ abcWaelkens, Christoffel (1993). "Slowly Pulsating B Stars". In J. M. NEMEC (Ed), Jaymie M. Matthews (ed.). New Perspectives on Stellar Pulsation and Pulsating Variable Stars: IAU Colloquium 139. Cambridge University Press. pp. 180–82. ISBN978-0-521-44382-1.
^John R. Percy (2007). Understanding Variable Stars. Cambridge University Press. pp. 137–38, 200–02. ISBN978-1-139-46328-7.
^Huang, L.; Guo, Z.; Hao, J.; Percy, J. R.; Fieldus, M. S.; Fried, R.; Pavlovski, K.; Bozic, H.; Ruzic, Z.; Paparo, M.; Vetoe, B. (August 1994). "A Multisite UBV Photometric Campaign on 53 Persei in 1991 January". The Astrophysical Journal. 431: 850–869. doi:10.1086/174536. Retrieved 16 February 2022.
^ abSamus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
^"VARIABLE STAR TYPE DESIGNATIONS IN VSX". Retrieved 2016-12-08.
^Miglio, A. (2007). "Revised instability domains of SPB and β Cephei stars". Communications in Asteroseismology. 151: 48–56. arXiv:0706.3632. Bibcode:2007CoAst.151...48M. doi:10.1553/cia151s48. ISSN 1021-2043.
^de Cat, P. (2007). "Observational Asteroseismology of slowly pulsating B stars". Communications in Asteroseismology. 150: 167–74. Bibcode:2007CoAst.150..167D. doi:10.1553/cia150s167.
January 10, 2023
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A slowly pulsating B type star SPB formerly known as a 53 Persei variable is a type of pulsating variable star They may also be termed a long period pulsating B star LPB 1 As the name implies they are main sequence stars of spectral type B2 to B9 3 to 9 times as massive as the Sun that pulsate with periods between approximately half a day and five days 2 however within this most member stars have been found to have multiple periods of oscillations 3 They display variability both in their light emission and in their spectral line profile The variations in magnitude are generally smaller than 0 1 magnitudes 2 making it quite hard to observe variability with the naked eye in most cases The variability increases with decreasing wavelength 3 thus they are more obviously variable in ultraviolet spectrum than visible light Their pulsations are non radial that is they vary in shape rather than volume different parts of the star are expanding and contracting simultaneously 4 A visual band light curve for V469 Persei 53 Persei plotted from data published by Huang et al 1994 This star was the prototype for this class of variable stars 5 These stars were first identified as a group and named by astronomers Christoffel Waelkens and Fredy Rufener in 1985 while looking for and analysing variability in hot blue stars Improvements in photometry had made finding smaller changes in magnitude easier and they had found that a high percentage of hot stars were intrinsically variable They referred to them as 53 Persei stars after the prototype 53 Persei 6 Ten had been discovered by 1993 though Waelkens was unsure if the prototype was actually a member and recommended referring to the group as slowly pulsating B SPB stars 3 The General Catalogue of Variable Stars uses the acronym LPB for comparatively long period pulsating B stars periods exceeding one day 7 although this terminology is rarely seen elsewhere 8 The similar Beta Cephei variables have shorter periods and have p mode pulsations while the SPB stars show g mode pulsations 9 By 2007 51 SPB stars had been confirmed with another 65 stars possible members Six stars namely Iota Herculis 53 Piscium Nu Eridani Gamma Pegasi HD 13745 V354 Persei and 53 Arietis had been found to exhibit both Beta Cephei and SPB variability 10 List EditThe following list contains selected slowly pulsating B type stars that are of interest to amateur or professional astronomy Unless otherwise noted the given magnitudes are in the V band Star Averagemagnitude Spectraltype Period in days Distance in parsecs Gamma Pegasi 2 84 B2IV n 1 113Zeta Pegasi 3 41 B8V 0 96 63Omicron Velorum 3 63 B3IV 2 80 151Iota Herculis 3 80 B3IV 3 49 139Gamma Muscae 3 88 B3V 2 73 100Tau Herculis 3 90 B5IV 1 25 94Nu Eridani 3 92 B2III n 1 207Mu Eridani 4 00 B5IV n 2 160Rho Lupi 4 05 B5V 0 45 97HD 105382 4 47 B6IIIe 1 30 134Tau8 Eridani 4 63 B5V 0 86 116Nu Pavonis 4 64 B7III 0 86 135HY Velorum 4 82 B3IV 1 55 148HD 131120 5 01 B7IIIp 1 57 151HR 5780 5 17 B5V 1 26 1223 Vulpeculae 5 19 B6III 1 26 12012 Lacertae 5 23 B2III n 1 411WZ Columbae 5 29 B9 5V 1 38 131V575 Persei 5 30 B5V 166Xi Octantis 5 31 B6V 1 77 15140 Tauri 5 33 B5V 1 53 19625 Serpentis 5 39 B8III 0 87 188GU Eridani 5 43 B5IV 1 87 200HR 3600 5 54 B5V 132KL Velorum 5 56 7 B8 2 91 212HD 1976 5 58 B5IV 1 06 307V450 Carinae 5 64 B9III B8V 1 65 151EO Leonis 5 66 B2V 2 78 289V539 Arae 5 71 B2 B3Vnn n 2 303HD 128207 5 73 B8V 0 48 147HD 27563 5 84 B5III 3 80 24226 Canis Majoris 5 90 B2IV V 2 73 25716 Monocerotis 5 92 B3V 1 94 263V335 Velorum 5 93 B 25III 3 76 704V869 Centauri 5 96 B9IV 1 46 251V363 Puppis 5 97 B2 5V B9V 0 70 278V433 Aurigae 5 99 B2IV V 4 64 325V1141 Tauri 6 00 B8IV V 0 62 170HD 206540 6 05 B5IV 1 39 215HR 1397 6 07 B6IV 1 26 198V576 Persei 6 09 B7V 0 84 159V2100 Cygni 6 11 B5III 2 61 239HR 2517 6 15 B2 5III 2 56 2500V492 Carinae 6 18 B3V 1 06 370HR 1328 6 20 B9V 0 38 121V4199 Sagittarii 6 26 B5III 1 24 240HR 3562 6 26 B3IV 370V4198 Sagittarii 6 28 B8V 1 19 186V377 Lacertae 6 32 B7III 2 62 305DY Chamaeleontis 6 32 B8IV 0 97 236HR 2680 6 33 B3V n 2 258V473 Carinae 6 35 B5V 0 95 218V405 Lacertae 6 37 B5V 1 02 170HD 34798 6 39 B5Vs 1 28 263HD 176582 6 40 B5V 1 58 292V1377 Orionis 6 41 B3III 1 01 476HR 8768 6 42 B2V 3 25 326GY Eridani 6 42 B3V 1 33 220QZ Velorum 6 49 B1IIIn 1 03 813V550 Lyrae 6 49 B3V 1 69 379HD 208727 6 50 B8V 0 32 330HD 43317 6 61 B3IV n 1 36923 Sextantis 6 64 B3 2IV n 1 769HD 33331 6 90 B5III 1 15 296HD 163868 7 36 B5Ve n 3 588HD 163899 8 30 B2Ib II 23 20HD 50209 8 36 B9Ve 0 67 694Notes Edit a b c d e Also a Beta Cephei variable a b c Also an Algol variable Also a shell starReferences Edit Samus N N et al 2017 General catalogue of variable stars Astronomy Reports GCVS 5 1 61 1 80 Bibcode 2017ARep 61 80S doi 10 1134 S1063772917010085 S2CID 125853869 a b Otero S A Watson C Wils P Variable Star Type Designations in the VSX AAVSO Website American Association of Variable Star Observers Retrieved 11 May 2014 a b c Waelkens Christoffel 1993 Slowly Pulsating B Stars In J M NEMEC Ed Jaymie M Matthews ed New Perspectives on Stellar Pulsation and Pulsating Variable Stars IAU Colloquium 139 Cambridge University Press pp 180 82 ISBN 978 0 521 44382 1 John R Percy 2007 Understanding Variable Stars Cambridge University Press pp 137 38 200 02 ISBN 978 1 139 46328 7 Huang L Guo Z Hao J Percy J R Fieldus M S Fried R Pavlovski K Bozic H Ruzic Z Paparo M Vetoe B August 1994 A Multisite UBV Photometric Campaign on 53 Persei in 1991 January The Astrophysical Journal 431 850 869 doi 10 1086 174536 Retrieved 16 February 2022 Waelkens Christoffel Rufener Fredy 1985 Photometric variability of mid B stars Astronomy amp Astrophysics 152 1 6 14 Bibcode 1985A amp A 152 6W a b Samus N N Durlevich O V et al 2009 VizieR Online Data Catalog General Catalogue of Variable Stars Samus 2007 2013 VizieR On line Data Catalog B GCVS Originally Published in 2009yCat 102025S 1 Bibcode 2009yCat 102025S VARIABLE STAR TYPE DESIGNATIONS IN VSX Retrieved 2016 12 08 Miglio A 2007 Revised instability domains of SPB and b Cephei stars Communications in Asteroseismology 151 48 56 arXiv 0706 3632 Bibcode 2007CoAst 151 48M doi 10 1553 cia151s48 ISSN 1021 2043 de Cat P 2007 Observational Asteroseismology of slowly pulsating B stars Communications in Asteroseismology 150 167 74 Bibcode 2007CoAst 150 167D doi 10 1553 cia150s167 Retrieved from https en wikipedia org w index php title Slowly pulsating B type star amp oldid 1072107834, wikipedia, wiki, book, books, library,
