کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1779833 1022041 2009 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Imprint of distortions in the Oort Cloud on the CMB anisotropies
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم نجوم و فیزیک نجومی
پیش نمایش صفحه اول مقاله
Imprint of distortions in the Oort Cloud on the CMB anisotropies
چکیده انگلیسی

We study the effect of a close encounter of a passing star on the shape of the inner Oort Cloud, using the impulse approximation. The deviation of the perturbed Oort Cloud from sphericity adds angular fluctuations to the brightness of the cosmic microwave background (CMB) due to thermal emission by the comets. An encounter with a solar-mass star at an impact parameter of 2100 AU, as expected based on the abundance and velocity dispersion of stars in the solar neighborhood, leads to a quadrupole moment C2=4.5(3.5)×10-15,6.7(1.1)×10-12,1.1(0.11)×10-9 at ν=30,353,545GHz, respectively in intensity and (temperature) fluctuations. We also quantify the quadrupole spectral distortions produced by the Scattered Disc, which will exist irregardless of any perturbation and the subsequent shape of the Oort Cloud. For comparison, the temperature fluctuation quadrupole moment predicted by the current cosmological model is C2=1.76×10-10C2=1.76×10-10, which corresponds to fluctuation in the CMB intensity of C2=2.9×10-10,6.8×10-9,1.6×10-8 at ν=30,353,545GHz. Finally, we discuss how a measurement of the anisotropic spectral distortions could be used to constrain the trajectory of the closest stellar fly-by.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: New Astronomy - Volume 14, Issue 2, February 2009, Pages 166–179
نویسندگان
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