M. Ajello, A. Rau, and J. Greiner, BAT X???Ray Survey. III. X???Ray Spectra and Statistical Properties, The Astrophysical Journal, vol.673, issue.1, p.96, 2008.
DOI : 10.1086/524104

A. Akylas and I. Georgantopoulos, XMM-Newton observations of Seyfert galaxies from the Palomar spectroscopic survey: the X-ray absorption distribution, Astronomy and Astrophysics, vol.500, issue.3, p.999, 2009.
DOI : 10.1051/0004-6361/200811371

A. Akylas, A. Georgakakis, I. Georgantopoulos, M. Brightman, and K. Nandra, Constraining the fraction of Compton-thick AGN in the Universe by modelling the diffuse X-ray background spectrum, Astronomy & Astrophysics, vol.546, p.98, 2012.
DOI : 10.1051/0004-6361/201219387

D. M. Alexander, F. E. Bauer, and W. N. Brandt, The Chandra Deep Field North Survey. XIII. 2 Ms Point-Source Catalogs, The Astronomical Journal, vol.126, issue.2, p.539, 2003.
DOI : 10.1086/376473

D. M. Alexander, F. E. Bauer, and S. C. Chapman, The X???Ray Spectral Properties of SCUBA Galaxies, The Astrophysical Journal, vol.632, issue.2, p.736, 2005.
DOI : 10.1086/444342

D. M. Alexander, R. R. Chary, and A. Pope, Mid???Infrared Spectroscopy of HDF???oMD49, The Astrophysical Journal, vol.687, issue.2, p.835, 2008.
DOI : 10.1086/591928

D. M. Alexander, F. E. Bauer, and W. N. Brandt, ??? 2 MASSIVE GALAXIES: THE IDENTIFICATION OF REFLECTION-DOMINATED ACTIVE GALACTIC NUCLEI, The Astrophysical Journal, vol.738, issue.1, p.44, 2011.
DOI : 10.1088/0004-637X/738/1/44

K. A. Arnaud, &. J. Jacoby, and . Barnes, Astronomical Data Analysis Software and Systems V, p.17, 1996.

I. Balestra, V. Mainieri, and P. Popesso, The Great Observatories Origins Deep Survey, Astronomy and Astrophysics, vol.512, issue.736, pp.12-56, 2010.
DOI : 10.1051/0004-6361/200913626

A. Barger, L. Cowie, and P. Capak, Optical and Infrared Properties of the 2 Ms Chandra Deep Field North X-Ray Sources, The Astronomical Journal, vol.126, issue.2, p.632, 2003.
DOI : 10.1086/376843

V. Braito, D. Ceca, R. Piconcelli, and E. , The XMM-Newton and BeppoSAX view of the Ultra Luminous Infrared Galaxy MKN??231, Astronomy & Astrophysics, vol.420, issue.1, p.79, 2004.
DOI : 10.1051/0004-6361:20040061

M. Brightman and K. Nandra, An XMM-Newton spectral survey of 12?????m selected galaxies - I. X-ray data, Monthly Notices of the Royal Astronomical Society, vol.413, issue.2, p.1206, 2011.
DOI : 10.1111/j.1365-2966.2011.18207.x

M. Brightman and . Ueda, The evolution of the Compton thick fraction and the nature of obscuration for active galactic nuclei in the Chandra Deep Field South, Monthly Notices of the Royal Astronomical Society, vol.423, issue.1, p.702, 2012.
DOI : 10.1111/j.1365-2966.2012.20908.x

D. Burlon, M. Ajello, and J. Greiner, -BAT SURVEY OF ACTIVE GALACTIC NUCLEI: RECONCILING THEORY AND OBSERVATIONS?, The Astrophysical Journal, vol.728, issue.1, p.58, 2011.
DOI : 10.1088/0004-637X/728/1/58
URL : https://hal.archives-ouvertes.fr/hal-00955877

E. Churazov, R. Sunyaev, and M. Revnivtsev, INTEGRAL observations of the cosmic X-ray background in??the??5???100??keV range via occultation by the Earth, Astronomy and Astrophysics, vol.467, issue.2, p.529, 2007.
DOI : 10.1051/0004-6361:20066230
URL : https://hal.archives-ouvertes.fr/in2p3-00135313

A. Comastri, K. Iwasawa, and R. Gilli, OBSERVATIONS OF HARD X-RAY-SELECTED SEYFERT 2 GALAXIES, The Astrophysical Journal, vol.717, issue.2, p.787, 2010.
DOI : 10.1088/0004-637X/717/2/787

A. Comastri, P. Ranalli, and K. Iwasawa, Deep survey in the CDF-S, Astronomy & Astrophysics, vol.526, issue.425, pp.9-2116, 2011.
DOI : 10.1051/0004-6361/201016119
URL : https://hal.archives-ouvertes.fr/cea-01135402

A. Corral, D. Ceca, R. Caccianiga, and A. , bright serendipitous survey, Astronomy & Astrophysics, vol.530, issue.670, pp.42-173, 2007.
DOI : 10.1051/0004-6361/201015227

T. Dahlen, B. Mobasher, and M. Dickinson, A DETAILED STUDY OF PHOTOMETRIC REDSHIFTS FOR GOODS-SOUTH GALAXIES, The Astrophysical Journal, vol.724, issue.1, p.425, 2010.
DOI : 10.1088/0004-637X/724/1/425

J. M. Dickey and F. J. Lockman, H I in the Galaxy, Annual Review of Astronomy and Astrophysics, vol.28, issue.1, p.215, 1990.
DOI : 10.1146/annurev.aa.28.090190.001243

M. E. Eckart, I. D. Mcgreer, D. Stern, F. A. Harrison, and D. J. Helfand, A COMPARISON OF X-RAY AND MID-INFRARED SELECTION OF OBSCURED ACTIVE GALACTIC NUCLEI, The Astrophysical Journal, vol.708, issue.1, p.584, 2010.
DOI : 10.1088/0004-637X/708/1/584

D. Elbaz, H. S. Hwang, and B. Magnelli, unveils a puzzling uniformity of distant dusty galaxies, Astronomy and Astrophysics, vol.518, issue.533, pp.29-119, 2010.
DOI : 10.1051/0004-6361/201014687

C. Feruglio, E. Daddi, and F. Fiore, = 2.5 AND 2.9, The Astrophysical Journal, vol.729, issue.1, pp.4-94, 2008.
DOI : 10.1088/2041-8205/729/1/L4

F. Fiore, S. Puccetti, and M. Brusa, CHASING HIGHLY OBSCURED QSOs IN THE COSMOS FIELD, The Astrophysical Journal, vol.693, issue.1, p.447, 2009.
DOI : 10.1088/0004-637X/693/1/447
URL : https://hal.archives-ouvertes.fr/hal-00370687

J. Fritz, A. Franceschini, and E. Hatziminaoglou, Revisiting the infrared spectra of active galactic nuclei with a new torus emission model, Monthly Notices of the Royal Astronomical Society, vol.366, issue.3, p.767, 2006.
DOI : 10.1111/j.1365-2966.2006.09866.x

F. Frontera, M. Orlandini, and R. Landi, The Cosmic X???Ray Background and the Population of the Most Heavily Obscured AGNs, The Astrophysical Journal, vol.666, issue.1, p.86, 2007.
DOI : 10.1086/519985

P. Gandhi, H. Horst, and A. Smette, Resolving the mid-infrared cores of local Seyferts, Astronomy and Astrophysics, vol.502, issue.2, p.457, 2009.
DOI : 10.1051/0004-6361/200811368

I. Georgantopoulos, I. Georgantopoulos, A. Georgakakis, and A. Akylas, Chandra and Spitzer observations of CDFS X-ray obscured QSOs, Astronomy and Astrophysics, vol.466, issue.3, p.823, 2007.
DOI : 10.1051/0004-6361:20065096

I. Georgantopoulos, A. Georgakakis, M. Rowan-robinson, and E. Rovilos, Searching for mid-IR obscured AGN in the Chandra deep field North, Astronomy and Astrophysics, vol.484, issue.3, p.671, 2008.
DOI : 10.1051/0004-6361:20078790

I. Georgantopoulos, A. Akylas, A. Georgakakis, and M. Rowan-robinson, The Compton-thick AGN in the Chandra Deep Field North, Astronomy and Astrophysics, vol.507, issue.2, p.747, 2009.
DOI : 10.1051/0004-6361/200912395

I. George and A. C. Fabian, X-ray reflection from cold matter in Active Galactic Nuclei and X-ray binaries, Monthly Notices of the Royal Astronomical Society, vol.249, issue.2, p.352, 1991.
DOI : 10.1093/mnras/249.2.352

R. Giacconi, H. Gursky, F. R. Paolini, and B. B. Rossi, Evidence for x Rays From Sources Outside the Solar System, Physical Review Letters, vol.9, issue.11, p.439, 1962.
DOI : 10.1103/PhysRevLett.9.439

R. Giacconi, A. Zirm, and J. Wang, Deep Field South: The 1 Ms Catalog, The Astrophysical Journal Supplement Series, vol.139, issue.2, p.369, 2002.
DOI : 10.1086/338927

R. Gilli, A. Comastri, and G. Hasinger, The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era, Astronomy and Astrophysics, vol.463, issue.1, p.79, 2007.
DOI : 10.1051/0004-6361:20066334

R. Gilli, C. Vignali, and M. Mignoli, The X-ray to [Ne V]3426 flux ratio: discovering heavily obscured AGN in the distant Universe, Astronomy and Astrophysics, vol.519, issue.730, pp.92-411, 2010.
DOI : 10.1051/0004-6361/201014039

L. Fèvre, O. Vettolani, G. Garilli, and B. , The VIMOS VLT deep survey, Astronomy and Astrophysics, vol.439, issue.3, p.845, 2005.
DOI : 10.1051/0004-6361:20041960

B. D. Lehmer, W. N. Brandt, and D. M. Alexander, Point???Source Catalogs, The Astrophysical Journal Supplement Series, vol.161, issue.1, p.21, 2005.
DOI : 10.1086/444590

B. Luo, F. E. Bauer, and W. N. Brandt, Deep Field???South Survey: 2 Ms Source Catalogs, The Astrophysical Journal Supplement Series, vol.179, issue.1, p.19, 2008.
DOI : 10.1086/591248

I. Georgantopoulos, Compton thick AGN in the CDF-S

B. Luo, W. N. Brandt, and Y. Q. Xue, IDENTIFICATIONS AND PHOTOMETRIC REDSHIFTS OF THE 2 Ms CHANDRA DEEP FIELD-SOUTH SOURCES, The Astrophysical Journal Supplement Series, vol.187, issue.2, p.560, 2010.
DOI : 10.1088/0067-0049/187/2/560

D. Lutz, R. Maiolino, H. W. Spoon, and A. F. Moorwood, The relation between AGN hard X-ray emission and mid-infrared continuum from ISO spectra: Scatter and unification aspects, Astronomy and Astrophysics, vol.418, issue.2, p.465, 2004.
DOI : 10.1051/0004-6361:20035838

B. Magnelli, D. Elbaz, and R. R. Chary, < 1.3 star formation history of the Universe as viewed in the far-infrared, Astronomy and Astrophysics, vol.496, issue.1, p.57, 2009.
DOI : 10.1051/0004-6361:200811443

V. Mainieri, A. Bongiorno, and A. Merloni, Black hole accretion and host galaxies of obscured quasars in XMM-COSMOS, Astronomy & Astrophysics, vol.535, issue.468, pp.80-979, 2007.
DOI : 10.1051/0004-6361/201117259
URL : https://hal.archives-ouvertes.fr/hal-01428160

G. Matt, S. Bianchi, M. Guainazzi, and S. Molendi, The high energy emission line spectrum of NGC??1068, Astronomy & Astrophysics, vol.414, issue.1, p.155, 2004.
DOI : 10.1051/0004-6361:20031635

A. Moretti, C. Pagani, and G. Cusumano, A new measurement of the cosmic X-ray background, Astronomy and Astrophysics, vol.493, issue.2, p.501, 2009.
DOI : 10.1051/0004-6361:200811197

A. Moretti, S. Vattakunnel, and P. Tozzi, Spectrum of the unresolved cosmic X-ray background: what is unresolved 50??years after its discovery, Astronomy & Astrophysics, vol.548, issue.414, pp.87-1082, 2011.
DOI : 10.1051/0004-6361/201219921

E. J. Murphy, J. J. Condon, and E. Schinnerer, CALIBRATING EXTINCTION-FREE STAR FORMATION RATE DIAGNOSTICS WITH 33 GHz FREE-FREE EMISSION IN NGC 6946, The Astrophysical Journal, vol.737, issue.2, p.67, 2011.
DOI : 10.1088/0004-637X/737/2/67

R. Nordon, D. Lutz, and R. Genzel, THE IMPACT OF EVOLVING INFRARED SPECTRAL ENERGY DISTRIBUTIONS OF GALAXIES ON STAR FORMATION RATE ESTIMATES, The Astrophysical Journal, vol.745, issue.2, pp.182-218, 2002.
DOI : 10.1088/0004-637X/745/2/182

R. P. Norris, J. Afonso, and P. N. Appleton, Wide?Area Infrared Extragalactic Field, The Astronomical Journal, vol.132, issue.6, p.2409, 2006.
DOI : 10.1086/508275

S. Paltani, R. Walter, and I. M. Mchardy, A deep INTEGRAL hard X-ray survey of the 3C??273/Coma region, Astronomy and Astrophysics, vol.485, issue.3, p.707, 2008.
DOI : 10.1051/0004-6361:200809450

P. Ranalli, A. Comastri, and C. Vignali, The XMM deep survey in the CDF-S, Astronomy & Astrophysics, vol.555, issue.465, pp.42-1099, 2007.
DOI : 10.1051/0004-6361/201321211
URL : https://hal.archives-ouvertes.fr/cea-01135402

C. Ricci, R. Walter, T. J. Courvoisier, S. Paltani, D. J. Rosario et al., Reflection in Seyfert galaxies and the unified model of AGN, Astronomy & Astrophysics, vol.532, issue.466, pp.102-119, 2007.
DOI : 10.1051/0004-6361/201016409

E. Rovilos, A. Comastri, and R. Gilli, observations reveal AGN/star-formation connection, Astronomy & Astrophysics, vol.546, issue.504, pp.58-751, 2009.
DOI : 10.1051/0004-6361/201218952

P. Santini, D. J. Rosario, and L. Shao, observations, Astronomy & Astrophysics, vol.540, issue.482, pp.109-517, 2008.
DOI : 10.1051/0004-6361/201118266
URL : https://hal.archives-ouvertes.fr/in2p3-00379829

J. D. Silverman, V. Mainieri, and M. Salvato, DEEP FIELD-SOUTH SURVEY: OPTICAL SPECTROSCOPY OF FAINT X-RAY SOURCES WITH THE VLT AND KECK, The Astrophysical Journal Supplement Series, vol.191, issue.1, p.124, 2010.
DOI : 10.1088/0067-0049/191/1/124

X. W. Shu, T. Yaqoob, and J. X. Wang, HIGH-ENERGY GRATING OBSERVATIONS OF THE Fe K?? LINE CORE IN TYPE II SEYFERT GALAXIES: A COMPARISON WITH TYPE I NUCLEI, The Astrophysical Journal, vol.738, issue.2, p.147, 2011.
DOI : 10.1088/0004-637X/738/2/147

G. P. Szokoly, J. Bergeron, and G. Hasinger, The Chandra Deep Field???South: Optical Spectroscopy. I., The Astrophysical Journal Supplement Series, vol.155, issue.2, p.271, 2004.
DOI : 10.1086/424707

E. N. Taylor, M. Franx, and P. G. Van-dokkum, -SELECTED, OPTICAL-TO-NEAR-INFRARED CATALOG OF THE EXTENDED CHANDRA DEEP FIELD SOUTH (ECDFS) FROM THE MULTIWAVELENGTH SURVEY BY YALE-CHILE (MUSYC), The Astrophysical Journal Supplement Series, vol.183, issue.2, p.295, 2009.
DOI : 10.1088/0067-0049/183/2/295
URL : https://hal.archives-ouvertes.fr/hal-00309715

E. Treister, C. M. Urry, and S. Virani, THE SPACE DENSITY OF COMPTON-THICK ACTIVE GALACTIC NUCLEUS AND THE X-RAY BACKGROUND, The Astrophysical Journal, vol.696, issue.1, p.110, 2009.
DOI : 10.1088/0004-637X/696/1/110

J. T. Turner, I. M. George, K. Nandra, and R. F. Mushotzky, Observations of Type 2 Seyfert Galaxies. II. The Importance of X???Ray Scattering and Reflection, The Astrophysical Journal, vol.488, issue.1, p.164, 1997.
DOI : 10.1086/304701

L. M. Winter, R. F. Mushotzky, C. S. Reynolds, and J. Tueller, X-RAY SPECTRAL PROPERTIES OF THE BAT AGN SAMPLE, The Astrophysical Journal, vol.690, issue.2, p.1322, 2009.
DOI : 10.1088/0004-637X/690/2/1322

M. A. Worsley, A. C. Fabian, and F. E. Bauer, The unresolved hard X-ray background: the missing source population implied by the Chandra and XMM--Newton deep fields, Monthly Notices of the Royal Astronomical Society, vol.357, issue.4, p.1281, 2005.
DOI : 10.1111/j.1365-2966.2005.08731.x

M. A. Worsley, A. C. Fabian, G. G. Pooley, and C. J. Chandler, Radio and X-ray observations of an exceptional radio flare in the extreme z= 4.72 blazar GB B1428+4217, Monthly Notices of the Royal Astronomical Society, vol.368, issue.2, p.844, 2006.
DOI : 10.1111/j.1365-2966.2006.10173.x

Y. Q. Xue, S. X. Wang, and W. N. Brandt, TRACKING DOWN THE SOURCE POPULATION RESPONSIBLE FOR THE UNRESOLVED COSMIC 6-8 keV BACKGROUND, The Astrophysical Journal, vol.758, issue.2, p.129, 2012.
DOI : 10.1088/0004-637X/758/2/129

T. Yaqoob, X???Ray Transmission in Cold Matter: Nonrelativistic Corrections for Compton Scattering, The Astrophysical Journal, vol.479, issue.1, p.184, 1997.
DOI : 10.1086/303843