This paper begins a series studying D-modules on the Feigin-Frenkel semi-infinite flag variety from the perspective of the Beilinson-Drinfeld factorization (or chiral) theory. Here we calculate Whittaker-twisted cohomology groups of Zastava spaces, which are certain finite-dimensional subvarieties of the affine Grassmannian. We show that such cohomology groups realize the nilradical of a Borel ...

We consider Bayesian constraints on standard isocurvature baryon models from the slope and normalization of the anisotropy power spectrum detected by the COBE DMR experiment in their 2 year maps. In conjunction with either the amplitude of matter fluctuations s8 or its slope, all open models are ruled out at greater than 95% confidence, whereas cosmological-constant dominated models are constra...

We investigate the non-gravitational heating of hot gas in clusters of galaxies (intracluster medium; ICM) on the assumption that the gas is heated well before cluster formation (’preheating’). We examine the jet activities of radio galaxies as the sources of excess energy in ICM, and the deformation of the cosmic microwave background (the Sunyaev-Zel’dovich effect) by hot electrons produced at...

Received ; accepted – 2 – ABSTRACT We estimate the level of confusion of Cosmic Microwave Background (CMB) anisotropy measurements caused by extragalactic infrared sources. CMB anisotropy observations at high resolution and high frequencies are especially sensitive to this foreground. We have combined IRAS data on bright infrared galaxies with information about the Galaxy from the DIRBE and FIR...

One still cannot conclusively assert that the universe underwent a neutral phase, despite the new COBE FIRAS limit y < 2.5× 10 on Compton y-distortions of the cosmic microwave background. Although scenarios where the very early (z ∼ 1000) ionization is thermal (caused by IGM temperatures exceeding 10K) are clearly ruled out, there is a significant loophole for cosmologies with typical CDM param...

The attenuation of very high energy γ-rays by pair production on the Galactic interstellar radiation field has long been thought of as negligible. However, a new calculation of the interstellar radiation field consistent with multi-wavelength observations by DIRBE and FIRAS indicates that the Galactic interstellar radiation field is intense. We have made a calculation of the attenuation of very...

Recent studies of galactic nuclei suggest that most galaxies are seeded by super-massive black holes which power the central nucleus. In this picture, the proto-galactic object is likely to have undergone a very active phase during which the surrounding medium was shocked and heated up to very high temperatures. We predict the cosmological effects of this scenario in terms of the thermal and ki...

FIRBACK is a deep survey conducted with the ISOPHOT instrument aboard the Infrared Space Observatory (ISO) at an effective wavelength of 175 μm. We present here results we have obtained on the first field, the so-called Marano1 which covers around 0.25 square degree. We find that the source density for objects with a flux above 200 mJy exceeds the counts expected for sources found in the IRAS d...

Our view on the deep universe has been so far biased towards optically bright galaxies. Now, the measurement of the Cosmic Infrared Background in FIRAS and DIRBE residuals, and the observations of FIR/submm sources by the ISOPHOT and SCUBA instruments begin unveiling the “optically dark side” of galaxy formation. Though the origin of dust heating is still unsolved, it appears very likely that a...

One still cannot conclusively assert that the universe underwent a neutral phase, despite the new COBE FIRAS limit y < 2.5 × 10 −5 on Compton y-distortions of the cosmic microwave background. Although scenarios where the very early (z ∼ 1000) ionization is thermal (caused by IGM temperatures exceeding 10 4 K) are clearly ruled out, there is a significant loophole for cosmologies with typical CD...