2007A&A...471..439M


C.D.S. - SIMBAD4 rel 1.7 - 2020.02.24CET01:22:58

2007A&A...471..439M - Astronomy and Astrophysics, volume 471, 439-452 (2007/8-4)

New limits on the density of the extragalactic background light in the optical to the far infrared from the spectra of all known TeV blazars.

MAZIN D. and RAUE M.

Abstract (from CDS):

The extragalactic background light (EBL) in the ultraviolet to far-infrared wavelength region carries important information about galaxy and star formation history. Direct measurements are difficult, especially in the mid infrared region. We derive limits on the EBL density from the energy spectra of distant sources of very high energetic γ-rays (VHE γ-rays). The VHE γ-rays are attenuated by the photons of the EBL via pair production, which leaves an imprint on the measured spectra from distant sources. So far, there are 14 detected extragalactic sources of VHE γ-rays, 13 of which are TeV blazars. With physical assumptions about the intrinsic spectra of these sources, limits on the EBL can be derived. In this paper we present a new method of deriving constraints on the EBL. Here, we use only very basic assumptions about TeV blazar physics and no pre-defined EBL model, but instead a large number of generic shapes constructed from a grid in EBL density vs. wavelength. In our study we utilize spectral data from all known TeV blazars, making this the most complete study so far. We derive limits on the EBL for three individual TeV blazar spectra (Mkn501, H1426+428, 1ES1101-232) and for all spectra combined. Combining the results from individual spectra leads to significantly stronger constraints over a wide wavelength range from the optical (∼1µm) to the far-infrared (∼80µm). The limits are only a factor of 2 to 3 above the absolute lower limits derived from source counts. In the mid-infrared our limits are the strongest constraints derived from TeV blazar spectra so far over an extended wavelength range. A high density of the EBL around 1µm, reported by direct detection experiments, can be excluded. Our results can be interpreted in two ways. (i) The EBL is almost resolved by source counts, leaving only a little room for additional components, such as the first stars, or (ii) the assumptions about the underlying physics are not valid, which would require substantial changes in the standard emission models of TeV blazars.

Abstract Copyright:

Journal keyword(s): galaxies: BL Lacertae objects: general - cosmology: diffuse radiation - galaxies: active - gamma rays: observations - infrared: general

CDS comments: Paragraph 6. 1ES 1110-232 is a misprint for 1ES 1101-232.

Simbad objects: 13

goto Full paper

goto View the reference in ADS

Number of rows : 13

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 2A 1058-226 BLL 11 03 37.6150843895 -23 29 31.202114088   17.00 16.55 16.61   ~ 308 2
2 Mrk 421 BLL 11 04 27.3139210166 +38 12 31.798324828   13.50 12.90 8.31   ~ 2352 1
3 6C 113337+702604 BLL 11 36 26.4093954222 +70 09 27.311486691   15.16 14.49 10.51   ~ 310 1
4 QSO B1218+304 BLL 12 21 21.9427463316 +30 10 37.161573795   16.50 15.85 15.7   ~ 382 1
5 M 87 BiC 12 30 49.42338230 +12 23 28.0438581 10.16 9.59 8.63   7.49 ~ 6104 3
6 QSO B1426+428 BLL 14 28 32.6090831425 +42 40 21.050020627   16.95 16.45 14.4   ~ 450 2
7 QSO B1553+113 BLL 15 55 43.0439413597 +11 11 24.365587666 14.91 14.72 14.57 13.99   ~ 405 1
8 4C 39.49 BLL 16 53 52.21668494 +39 45 36.6089458 14.09 14.15 13.29 8.26   ~ 1893 2
9 QSO B1959+650 BLL 19 59 59.8525497024 +65 08 54.651170114     12.8 11.21   ~ 492 2
10 QSO B2005-489 BLL 20 09 25.3910622923 -48 49 53.722146927   15.75 12.81 11.41   ~ 504 2
11 QSO B2155-304 BLL 21 58 52.0651817803 -30 13 32.120657891   13.36 13.09 12.62   ~ 1534 1
12 QSO B2344+514 BLL 23 47 04.8376303689 +51 42 17.875387216     15.50 10.7   ~ 382 0
13 QSO B2356-309 BLL 23 59 07.9032684889 -30 37 40.667900741   18.414 16.44 16.795   ~ 244 1

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2007A&A...471..439M and select 'bookmark this link' or equivalent in the popup menu


2020.02.24-01:22:58

© Université de Strasbourg/CNRS

    • Contact