• Infrastructure
• General Overview
• Optics
• Cryogenics
• Bolometer Array
• Data Acquisition
• Polarimeter

• Observing with LABOCA
• Spectral Response
• Observing Modes
• Sensitivity
• Data Reduction
• Science with LABOCA

• Other
• People
• Useful Links
• Picture Gallery
• Thermonitor

• Main Page

Because of its spectral passband, centred at a wavelength of 870 µm, LABOCA is particularly sensitive to thermal emission from cold objects which is of great interest for a number of astrophysical research fields.


Planet Formation
The study of Kuiper Belt Objects in the solar system as well as observations of debris disks of cold dust around nearby main sequence stars can give vital clues to the formation of our own solar system and planets in general. With the angular resolution of 18“.6, LABOCA will be capable to resolve the debris disks of nearby stars.


Star Formation in the Milky Way
The outstanding power of LABOCA in mapping large areas of the sky with high sensitivity will allow for the first time to perform unbiased surveys of the distribution of the cold dust in the Milky Way.

As the dust emission at 870 µm is typically optically thin, it is a direct tracer of the gas column density and gas mass. Large scale surveys in the Milky Way will reveal the distribution and gas properties of a large number of pre-stellar cores in different environments and evolutionary states. Equally importantly, they provide information on the structure of the interstellar medium on large scales at high spatial resolution, little explored so far. Such surveys are vital to improve our understanding of the processes that govern star formation as well as the relation between the clump mass spectrum and the stellar initial mass function (IMF).

Large unbiased surveys are also critical for finding precursors of high-mass stars,  which are undetectable at other wavelengths due to the high obscuration of the massive cores they are embedded in. LABOCA will help to obtain a detailed understanding of their evolution.

In addition, deep surveys of nearby, star forming clouds, will allow to study the pre-stellar mass function down to the brown dwarf regime.


Cold gas in Galaxies
The only reliable way to trace the bulk of dust in galaxies is through imaging at submillimeter wavelengths. It is becoming clear that most of the dust mass in spiral galaxies lies in cold, low-surface brightness disks, often extending far from the galactic nucleus. Understanding this component is critically important as it dominates the total gas mass in galaxies. Therefore e.g. studies of the Schmidt Law based on HI observations alone heavily underestimate the gas surface density in the outer parts of galaxies. In addition to studying individual nearby galaxies, LABOCA will be vital for determining the low-z benchmarks, such as the local luminosity and dust mass functions, which are required to interpret information from deep cosmological surveys.


Galaxy formation at high redshift
Due to the negative-K correction submillimeter observations offer equal sensitivity to dusty star forming galaxies over a redshift range from z~1-10 and therefore provide information on the star formation history at epochs from about half to only 5% of the present age of the universe. Recent studies have shown that the volume density of luminous submillimeter galaxies (SMGs) increases over a thousand-fold out to z < 2 (Chapman et al., 2005), and thus, in contrast to the local Universe, luminous obscured galaxies at high redshift could dominate the total bolometric emission from all galaxies at early epochs. These studies also suggest that approximately half of all the stars that have formed by the present day may have formed in highly obscured systems which remain undetected in the optical or NIR. One example of these sources is SMM14009+0252 which is strong in the submillimeter, and has a 1.4 GHz radio counter part but no obvious counter part in deep K-band images (Ivison et.al., 2000). Clearly it is critical to include these highly-obscured sources in models of galaxy formation to obtain a complete understanding of the evolution of galaxies. With its fast mapping capabilities LABOCA allows us to map fields of a half square degree, typical size of deep cosmological fields observed at other wavelength, down to the confusion limit in a reasonable amount of observing time. This will also greatly improve the statistics of high redshift galaxies deteced at submillimeter wavelengths.

A set of science verification projects has been observed with LABOCA. The raw and reduced data are publicly available here.

References
Chapman S. C. et al. 2005, ApJ 622, 722
Ivison R. J. et al. 2000, MNRAS 315, 209