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Register a new userGround-based CCD astrometry with wide field imagers. IV. An improved Geometric Distortion Correction for the Blue prime-focus Camera at the LBT
تصحيح التشوه الهندسي المحسن للكاميرا الأزرق الموجهة في البوابة الأصلية في لبت باستخدام المسح الأستروني المستند على الأرض مع العدسات الواسعة. الجزء الرابع
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A. Bellini Univ. PD
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طلب الدقة العالية في الأسترومترية يتطلب حلاً تصحيحياً رياضياً دقيقاً. في هذا العمل، نقدم تصحيحاً متوسطاً للكاميرا الزرقاء لمجموعة العدسات الكبيرة التي تتيح دقة استرومترية نسبية تقريباً بمقدار 15 ماس لمرشحي الباند الضوئي B_Bessel و V_Bessel. يتم استخدام نتيجة هذا الجهد في عمليتين مرشحتين: الأول هو قياس الحركة الصحيحة المطلقة لمجموعة النجوم المفتوحة M67 مقارنة بالأجرام الخلفية؛ والثاني هو تنظيف الرسم البياني اللون-المقياس لـ M67 من العناصر الحقلية، مما يتيح دراسة نهاية سلسلة تبريد الأشباح البيضاء. يمكن أن تجد كثير من التطبيقات الأخرى هذا التصحيح التشويشي مفيداً.
High precision astrometry requires an accurate geometric distortion solution. In this work, we present an average correction for the Blue Camera of the Large Binocular Telescope which enables a relative astrometric precision of ~15 mas for the B_Bessel and V_Bessel broad-band filters. The result of this effort is used in two companion papers: the first to measure the absolute proper motion of the open cluster M67 with respect to the background galaxies; the second to decontaminate the color-magnitude diagram of M67 from field objects, enabling the study of the end of its white dwarf cooling sequence. Many other applications might find this distortion correction useful.
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