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Tez.Pdf (1.804Mb) İÇİNDEKİLER SİMGELER DİZİNİ .......................................................................................................v ŞEKİLLER DİZİNİ ......................................................................................................vii ÇİZELGELER DİZİNİ .................................................................................................ix 1 GİRİŞ ......................................................................................................................1 1.1 W UMa Türü Örten Çift Yıldızlar (Değen Çift Yıldızlar) .................................7 1.2 Dönem - Yoğunluk ve Yarıçap Oranı - Kütle Oranı İlişkileri.........................11 1.3 W UMa Türü Örten Çiftlerde Işık Eğrisindeki Değişimler.............................13 2 MATERYAL VE YÖNTEM..............................................................................16 2.1 Çift Yıldızların Seçimi .........................................................................................16 2.2 İncelenen Çift Yıldızlar........................................................................................18 2.2.1 V781 Tauri ............................................................................................................18 2.2.2 UY Ursae Majoris ................................................................................................19 2.2.3 MW Pavonis..........................................................................................................20 2.2.4 RW Comae Berenices ..........................................................................................21 2.2.5 YZ Phoenics ..........................................................................................................23 3 ÇİFT YILDIZLARIN ANALİZİ........................................................................24 3.1 V781 Tau Çift Sisteminin Analizi .......................................................................25 3.2 UY UMa Çift Sisteminin Analizi ........................................................................28 3.3 MW Pav Çift Sisteminin Analizi.........................................................................30 3.4 RW Com Çift Sisteminin Analizi........................................................................32 3.5 YZ Phe Çift Sisteminin Analizi...........................................................................34 4 BULGULAR .........................................................................................................36 5 TARTIŞMA VE SONUÇ.....................................................................................39 KAYNAKLAR ..............................................................................................................43 EK 1 Dönem-Yoğunluk, Kütle Oranı-Yarıçap Oranı Bağıntılarında Kullanılan Çiftler .................................................................................................................48 EK 2 Işık Eğrilerinde O’connell Etkisi Görülen W Uma Türü Çift Sistemler .....54 ÖZGEÇMİŞ...................................................................................................................64 SİMGELER DİZİNİ a(R) Yörünge yarı-büyük eksen uzunluğu C Jacobi integral sabiti EA Algol türü ışık değişimi gösteren örten değişen sistemler EB β Lyrae türü ışık değişimi gösteren örten değişen sistemler EW W UMa türü ışık değişimi gösteren örten değişen sistemler G Evrensel çekim sabiti (G=6.67x10-11N.m2.Kg-2) i(º) Yörünge eğim açısı k Bileşenlerin yarıçapları oranı, k=r2/r1=R2/R1 K Kelvin derece L1,2 Sırasıyla birinci ve ikinci bileşenin ışınım güçleri 30 ) M Güneş kütlesi (M=1.99x10 kg m1,2 Sırasıyla ortak kütle merkezi etrafında çember yörüngede dolanan birinci ve ikinci bileşenin kütlesi M1,2(M) Sırasıyla baş bileşen ve yoldaş bileşenin kütlesi Mtop Bileşenlerin kütleleri toplamı P Çift sistemin “gün” cinsinden yörünge dönemi q Bileşenlerin kütleleri oranı, q=M2/M1 r Korelasyon katsayısı 5 R Güneş yarıçapı (R=6.96x10 km) r1,2 (back) Biçimi bozulmuş bileşenin L1 (1. Lagrange noktası) doğrultusundaki yarıçapı r1,2 (pole) Biçimi bozulmuş bileşenin kutup doğrultusundaki yarıçapı r1,2 (side) Biçimi bozulmuş bileşenin dörtlük yörünge evresinde, gözlemci doğrultusundaki yarıçapı r1,2 Bileşenlerin kesirsel ortalama yarıçapı R1,2(R) Sırasıyla baş bileşen ve yoldaş bileşenin yarıçapları T0 Jülyen günü cinsinden belirlenmiş başlangıç minimum zamanı, epoch T1,2 Sırasıyla baş bileşen ve yoldaş bileşenin sıcaklıkları V Sonsuz küçük kütlenin uzay hızı Δm O’Connell etkisi, Δm = MaxII - MaxI v ΔT Bileşen yıldızların sıcaklık farkları, ΔT = T2 – T1 σ Birim ağırlığın standart hatası Bileşen yıldızların gr/cm3 olarak ortalama yoğunlukları Açısal dönme hızı f Taşma (değme) parametresi Ortak zarfın potansiyeli 1,2 Sırasıyla birinci ve ikinci bileşenin yüzey potansiyeli dış Bileşenlerin kütle oranına karşılık gelen dış kritik yüzey potansiyeli iç Bileşenlerin kütle oranına karşılık gelen iç kritik yüzey potansiyeli vi ŞEKİLLER DİZİNİ Şekil 1.1 Bir çift yıldız sistemi için Roche eşpotansiyel yüzeyleri ve x, y düzlemindeki izdüşümleri..................................................................................3 Şekil 1.2 Ayrık çiftler........................................................................................................4 Şekil 1.3 Yarı ayrık çiftler.................................................................................................5 Şekil 1.4 Değen çiftler.......................................................................................................6 Şekil 1.5 Aşırı değen çiftler ..............................................................................................6 Şekil 1.6 A ve W alt türleri için tipik ışık ve dikine hız eğrileri......................................8 Şekil 1.7 W UMa’larda dönem-yoğunluk ve kütle oranı-yarıçap oranı ilişkileri ...........12 Şekil 1.8 O’Connell etkisi, II. ve I. maksimumlar arasındaki fark .................................14 Şekil 2.1 AB And’ın 1968 ve 1978 yılı B bandı ışık eğrileri .........................................16 Şekil 2.2 V781 Tau’nun V bandı ışık eğrisi ve (B-V) rengi ...........................................19 Şekil 2.3 UY UMa’nın B ve V ışık eğrileri ....................................................................20 Şekil 2.4 MW Pav’ın U,B ve V bantları ışık eğrileri......................................................21 Şekil 2.5 RW Com’un B ve V ışık eğrileri .....................................................................22 Şekil 2.6 YZ Phe’nn B ve V ışık eğrileri ........................................................................23 Şekil 3.1 V781 Tau’nun, B ve V bantlarında gözlenmiş ışık eğrisi................................25 Şekil 3.2 V781 Tau’nun, 0.0-0.5 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................26 Şekil 3.3 V781 Tau’nun, 0.5-1.0 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................26 Şekil 3.4 UY UMa’nın, 0.0-0.5 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................28 Şekil 3.5 UY UMa’nın, 0.5-1.0 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................29 Şekil 3.6 MW Pav’ın, 0.0-0.5 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................30 Şekil 3.7 MW Pav’ın, 0.5-1.0 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................31 Şekil 3.8 RW Com’un, 0.0-0.5 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................32 Şekil 3.9 RW Com’un, 0.5-1.0 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................33 Şekil 3.10 YZ Phe’in, 0.0-0.5 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................34 vii Şekil 3.11 YZ Phe’in, 0.5-1.0 evre aralığına göre elde edilmiş simetrik ışık eğrileri ve kuramsal ışık eğrileri ......................................................................35 Şekil 4.1 V781 Tau için analiz sonucu bulunan ve deneysel olarak belirlenen anabileşen ortalama yoğunluklarının karşılaştırılması.....................................38 viii ÇİZELGELER DİZİNİ Çizelge 1.1 Örten değişen çift yıldız türleri......................................................................1 Çizelge 1.2 W UMa Türü örten çift sistemlerin A ve W türleri arasındaki farklılıklar....9 Çizelge 2.1 Seçilen yıldızların genel özellikleri .............................................................17 Çizelge 3.1 V781 Tau sisteminin analiz sonuçları..........................................................27 Çizelge 3.2 UY UMa sisteminin analiz sonuçları...........................................................29 Çizelge 3.3 MW Pav sisteminin analiz sonuçları............................................................31 Çizelge 3.4 RW Com sistemin WD’de çözülmüş ışık eğrisi analiz sonuçları................33 Çizelge 3.5 YZ Phe çift sisteminin WD’de çözülmüş ışık eğrisi analiz sonuçları
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