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We present large scale 870 micron maps of the nearby starburst galaxies NGC253, NGC4945 and the nearest giant elliptical radio galaxy Centaurus A (NGC 5128) obtained with the newly commissioned Large Apex Bolometer Camera (LABOCA) operated at the APEX telescope. Our continuum images reveal for the first time the distribution of cold dust at a angular resolution of 20" across the entire optical disks of NGC253 and NGC4945 out to a radial distance of 10' (7.5 kpc). In NGC5128 our LABOCA image also shows, for the first time at submillimeter wavelengths, the synchrotron emission associated with the radio jet and the inner radio lobes. From an analysis of the 870 micron emission in conjunction with ISO-LWS, IRAS and long wavelengths radio data we find temperatures for the cold dust in the disks of all three galaxies of 17-20 K, comparable to the dust temperatures in the disk of the Milky Way. The total gas mass in the three galaxies is determined to be 2.1, 4.2 and 2.8 x 10^9 solar masses for NGC253, NGC4945 and NGC5128, respectively. A detailed comparison between the gas masses derived from the dust continuum and the integrated CO(1-0) intensity in NGC253 suggests that changes of the CO luminosity to molecular mass conversion factor are mainly driven by a metallicity gradient and only to a lesser degree by variations of the CO excitation. An analysis of the synchrotron spectrum in the northern radio lobe of NGC5128 shows that the synchrotron emission from radio to the ultraviolet wavelengths is well described by a broken power law and that the break frequency is a function of the distance from the radio core as expected for aging electrons. We derive an outflow speed of ~0.5c at a distance of 2.6kpc from the center, consistent with the speed derived in the vicinity of the nucleus., Comment: 12 pages, 11 figures. Accepted for publication in A&A

We present observations aimed at exploring both the nature of Lya emitting nebulae (Lya blobs) at z=2.38 and the way they trace large scale structure (LSS), by exploring their proximity to maximum starbursts through submillimeter emission. Our most important objectives are to make a census of associated submillimeter galaxies (SMGs), check their properties, and look for a possible overdensity in the protocluster J2142-4426 at z=2.38. We used the newly commissioned Large APEX Bolometer Camera (LABoCa) on the Atacama Pathfinder EXperiment (APEX) telescope, in its Science Verification phase, to carry out a deep 10'x10' map at 870 micron, and we performed multiple checks of the quality of data processing and source extraction. Our map, the first published deep image, confirms the capabilities of APEX/LABoCa as the most efficient current equipment for wide and deep submm mapping. Twenty-two sources were securely extracted with 870 micron flux densities in the range 3-21 mJy, rms noise 0.8-2.4 mJy, and far-IR luminosities probably in the range ~5-20 x 10(12) Lo. Only one of the four 50 kpc-extended Lya blobs has a secure 870 micron counterpart. The 870 micron source counts in the whole area are marginally higher than in the SHADES SCUBA survey, with a possible over-density around this blob. The majority of the 3.6-24 micron SEDs of the submillimeter sources indicate they are starburst dominated, with redshifts mostly >2. However, there is evidence of a high-z AGN in ~30% of the sources., Comment: 14 pages, 9 figures, accepted for publication in A&A, fixed author list

We have measured the Sunyaev-Zeldovich effect towards the Coma cluster (A1656) with the MITO experiment, a 2.6-m telescope equipped with a 4-channel 17 arcminute (FWHM) photometer. Measurements at frequency bands 143+/-15, 214+/-15, 272+/-16 and 353+/-13 GHz, were made during 120 drift scans of Coma. We describe the observations and data analysis that involved extraction of the S-Z signal by employing a spatial and spectral de-correlation scheme to remove a dominant atmospheric component. The deduced values of the thermal S-Z effect in the first three bands are DT_{0} = -179+/-38,-33+/-81,170+/-35 microKelvin in the cluster center. The corresponding optical depth, tau=(4.1+/-0.9) 10^{-3}, is consistent (within errors) with both the value from a previous low frequency S-Z measurement, and the value predicted from the X-ray deduced gas parameters., Comment: Ap.J.Letters accepted, 4 pages, 2 figures

We present observations at 250 GHz (1.2 mm), 43 GHz, and 1.4 GHz of a sample of 41 QSOs at z > 3.7 found in the Sloan Digital Sky Survey. We detect 16 sources with a 250 GHz flux density greater than 1.4 mJy. The combination of centimeter and millimeter wavelength observations indicates that the 250 GHz emission is most likely thermal dust emission. Assuming a dust temperature of 50 K, the implied dust masses for the 16 detected sources are in the range 1.5e8 to 5.9e8 Msun, and the dust emitting regions are likely to be larger than 1 kpc in extent. The radio-through-optical spectral energy distributions for these sources are within the broad range defined by lower redshift, lower optical luminosity QSOs. We consider possible dust heating mechanisms, including UV emission from the active nucleus (AGN) and a starburst concurrent with the AGN, with implied star formation rates between 500 and 2000 Msun/year., Comment: 4 figures, aasms4.sty. to appear in the Astrophysical Journal

We discuss results from sensitive, wide-field imaging of the millimeter extragalactic background using the Max-Planck Millimeter Bolometer array (MAMBO) at the IRAM 30m telescope., Comment: 4 pages, 3 figures, uses newpasp.sty. To appear in Proc. JD9, IAU Manchester 2000, `Cold Gas and Dust at High Redshift' ed. D.J. Wilner, Highlights of Astronomy Vol. 12. PASP

We summarize results from sensitive, wide-field imaging at 250 GHz using the Max-Planck Bolometer Array at the IRAM 30m telescope, including source counts, clustering, and redshift distribution., Comment: 5 pages. 'Deep Millimeter Surveys: Implications for Galaxy Formation and Evolution,' eds. Lowenthal and Hughes, World Scientific. For higher quality figures see: http://www.aoc.nrao.edu/~ccarilli/ccarilli.shtml

We present millimeter wavelength detections of three faint sources that are most likely high-redshift starburst galaxies. For one of the sources, which was previously discovered with SCUBA at 850 mu m, we present a detection with the IRAM interferometer at 240 GHz (1.25 mm) that shows the object unresolved at an angular resolution of 2.''5, and coincident within 1'' with a radio source and a galaxy detected in the near-infrared. The two other sources were discovered in a deep 250 GHz (1.2 mm) survey with the Max-Planck Millimeter Bolometer (MAMBO) array at the IRAM 30m telescope. Both have fluxes of ~4 mJy and radio counterparts with a 1.4 GHz flux density of ~75 muJy. Their radio-to-mm flux ratios suggest redshifts larger than 2. Both sources are faint in the optical and near-infrared, one showing a 20.5 mag K-band counterpart. From our data and that available in the literature, we estimate the redshift distribution of twenty-two faint mm and sub-mm sources and conclude that the majority of them are likely to be at z>2., Comment: 7 pages, 7 figures, A&A submitted

We present detections of emission at 250 GHz (1.2 mm) from two high redshift QSOs from the Sloan Digital Sky Survey sample using the bolometer array at the IRAM 30m telescope. The sources are SDSSp 015048.83+004126.2 at z = 3.7, and SDSSp J033829.31+002156.3 at z = 5.0, which is the third highest redshift QSO known, and the highest redshift mm emitting source yet identified. We also present deep radio continuum imaging of these two sources at 1.4 GHz using the Very Large Array. The combination of cm and mm observations indicate that the 250 GHz emission is most likely thermal dust emission, with implied dust masses of 1e8 M_solar. We consider possible dust heating mechanisms, including UV emission from the active nucleus (AGN), and a massive starburst concurrent with the AGN, with implied star formation rates > 1e3 M_solar/year., Comment: AAS LATEX format, 1 postscript figure. to appear in ApJ letters