کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1779605 | 1022011 | 2006 | 11 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Gamma-ray constraints on the infrared background excess
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موضوعات مرتبط
مهندسی و علوم پایه
فیزیک و نجوم
نجوم و فیزیک نجومی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Gamma-ray constraints on the infrared background excess Gamma-ray constraints on the infrared background excess](/preview/png/1779605.png)
چکیده انگلیسی
Motivated by the idea that the recently detected near-infrared (1.2-4 μm) excess over the contribution of known galaxies is due to redshifted light from the first cosmic stars [MNRAS 339 (2003) 973], we have used the effect caused by photon-photon absorption on gamma-ray spectra of blazars to put constraints on extragalactic background light (EBL) from the optical to the far-IR bands. Our analysis is mainly based on the blazar H 1426+428, for which we assume a power-law unabsorbed spectrum. We find that an EBL model with no excess over known galaxies in the near-infrared background (NIRB) is in agreement with all the considered blazars; however, it implies a very peculiar intrinsic spectrum for H 1426+428. Additional data on the blazars 1ES1101-232, H 2356-309 and PKS 2155-304 exclude the existence of a strong NIRB excess consistent with Kelsall's model of zodiacal light subtraction (ZL); the COBE/DIRBE measurements, after Wright's model ZL subtraction, represent a firm NIRB upper limit. The constraints on the optical EBL are weaker, due to the fact that predictions from different optical EBL models are often comparable to the experimental errors. In the mid-infrared the SPITZER measurement of νIν = 2.7 nW mâ2 srâ1 at 24 μm gives a good fit for all the considered blazars.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: New Astronomy - Volume 11, Issue 6, April 2006, Pages 420-430
Journal: New Astronomy - Volume 11, Issue 6, April 2006, Pages 420-430
نویسندگان
M. Mapelli, R. Salvaterra, A. Ferrara,