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تسجيل مستخدم جديدجولة سبيتزر c2d للسحبات الكبيرة والقريبة والفضائية. العاشرة. توزيع سيربنس للكواكب النووية الشبابية كما تم رصدها مع IRAC و MIPS
The Spitzer c2d Survey of Large, Nearby, Insterstellar Clouds. IX. The Serpens YSO Population As Observed With IRAC and MIPS
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نحن نناقش نتائج من الملاحظات التراثية المشتركة ل IRAC و MIPS c2d Spitzer في منطقة تشكيل النجوم Serpens. وخصوصا نقدم مجموعة من المعايير لاستخراج الأجسام النجمية الشابة الحقيقية، YSOs، من التلوث الخلفي الواسع من الأجسام الخارج المجرية. ثم نناقش خصائص المجموعة الناتجة من الأجسام النجمية الشابة الذي يؤمن بالثقة العالية. ونجد 235 عنصرا في مجال 0.85 deg ^ 2 الذي كان مغطى بكلا IRAC و MIPS. ويتم تحديد مجموعة إضافية من 51 عنصرا بثقة أقل خارج هذا المنطقة من بيانات MIPS مزدوجة مع التصوير الفوتوغرافي 2MASS. نحن نصفح مجموعتين من النتائج، الرسوم البيانية للألوان لمقارنة خصائص مصدرنا مع تلك النماذج النظرية لنظام النجم / القرص / الغلاف وتحليلنا الخاص لجزء من أجسامنا التي تبدو كنجمة + قرص. هذه الأجسام تظهر مجموعة واسعة جدا من خصائص القرص، من الكثير منها التي يمكن تناسبها مع القرص التي تتلقى الانتقالات بفعالية إلى بعض مع القرص الساكنة وحتى ربما القرص القمامة. ونجد أن دالة الإشعاع للأجسام النجمية الشابة في Serpens تمتد إلى أقل من بضعة مرات من 0.001 Lsun أو أقل لمقدار متوقع للمسافة 260 بايكلوميتر. وقد يتم تعيين الحد الأدنى من قبل عدم قدرتنا على التمييز بين الأجسام النجمية الشابة والمصادر الخارج المجرية أكثر من بسبب نقص الأجسام النجمية الشابة في الإشعاعات المنخفضة جدا. ويظهر تحليل التجمع المكاني أن الأجسام النجمية الشابة المبدئيا الأقل تجمعت بشكل أكبر من المراحل اللاحقة وأن التلوث الخلفي الخارج المجري يمكن تناسبه بنفس دالة الارتباط النقطي الثنائية التي تم الإبحار في الدراسات الخارج المجرية الأخرى. كما نقدم جدولا للمطابقات بين عدة دراسات الأشعة تحت الحمراء والأشعة فوق البنفسجية السابقة لمجموعة الأجسام النجمية الشابة في Serpens وبيانات Spitzer الخاصة بنا.
We discuss the results from the combined IRAC and MIPS c2d Spitzer Legacy observations of the Serpens star-forming region. In particular we present a set of criteria for isolating bona fide young stellar objects, YSOs, from the extensive background contamination by extra-galactic objects. We then discuss the properties of the resulting high confidence set of YSOs. We find 235 such objects in the 0.85 deg^2 field that was covered with both IRAC and MIPS. An additional set of 51 lower confidence YSOs outside this area is identified from the MIPS data combined with 2MASS photometry. We describe two sets of results, color-color diagrams to compare our observed source properties with those of theoretical models for star/disk/envelope systems and our own modeling of the subset of our objects that appear to be star+disks. These objects exhibit a very wide range of disk properties, from many that can be fit with actively accreting disks to some with both passive disks and even possibly debris disks. We find that the luminosity function of YSOs in Serpens extends down to at least a few x .001 Lsun or lower for an assumed distance of 260 pc. The lower limit may be set by our inability to distinguish YSOs from extra-galactic sources more than by the lack of YSOs at very low luminosities. A spatial clustering analysis shows that the nominally less-evolved YSOs are more highly clustered than the later stages and that the background extra-galactic population can be fit by the same two-point correlation function as seen in other extra-galactic studies. We also present a table of matches between several previous infrared and X-ray studies of the Serpens YSO population and our Spitzer data set.
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