A New Broadband Instrument for Measuring Light Absorption on Particulate Sample Filters

摘要

A new instrument called BITS has been designed and constructed to allow light absorption and fluorescence measurements to be made using a single broadband radiation source emitting in the UV to near-IR spectral range coupled via a custom bifurcated fiber optics bundle to a single 2-D CCD spectrometer with high spectral resolution. The system is fully automated and capable of handling the high throughput requirements of the IMPROVE network. BITS has been designed over the past two years but has just recently been assembled and is currently being tested and characterized at UC Davis. Upcoming work will entail (1) fine tuning calibration and data processing procedures, (2) incorporating full automation and a novel collections optics assembly into the system, (3) characterizing the instrument using various standards such as ammonium sulfate, elemental carbon and various organic compounds, (4) interpreting spectra of ambient PM samples, (5) comparing BITS broadband measurements to existing single wavelength HIPS measurements and (6) bringing the instrument online in the measurement routine of the IMPROVE network.