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The Telescope Array (TA) is an international experiment studying ultra-high energy cosmic rays. TA uses the fluorescence detection technique to observe cosmic rays. In order to estimate the energy of cosmic rays with a fluorescence detector (FD), it is necessary to measure the condition of the observation area. Clouds affect the accuracy of the energy estimation. It is necessary to measure the existence of clouds and their direction in the Field Of View (FOV) of the FD. We developed a cloud monitoring system to measure the night sky weather using a CCD camera. In this report, we present our progress on our CCD cloud monitoring system.

In the future, ultra-high energy cosmic ray (UHECR) observatory will be expanded due to the small flux. Then, cost reduction is useful strategy to realize a huge scale observatory. For this purpose, we are developing a simple structure cosmic ray detector named as Cosmic Ray Air Fluorescence Fresnel-lens Telescope (CRAFFT). We deployed CRAFFT detectors at the Telescope Array site and performed a test observation. We have successfully observed UHECR air showers. We will report the status and the result of the test observation.

We developed a compact but versatile laser-induced fluorescence spectrum (LIFS) lidar that has potential use for material or aerosol identification outside experimental rooms. The compactness and mobility of the LIFS lidar means observations can be more freely conducted at any place and any time. Its performance characteristics were validated by threedimensional fluorescence imaging of targets and remote detection of quasi bio/organic aerosols.

The laser-induced fluorescence spectra of living leaves of seven different trees were investigated by using a 355-nm pulsed Nd:YAG laser. The shapes of the spectra (360-800 rim) varied depending on the season and growing conditions. Generally, red fluorescence (>650 nm) was larger during summer to autumn, which offers information on the activity of photosynthesis, and blue-green fluorescence ( OCIS codes: 300.2530, 010.3640.

Three-primary-color laser emissions of blue, green, and red were simultaneously obtained by using a Coumarin 460 (C460)/Disodium Fluorescein (DF)/Cresyl Violet (CV) mixture and a C460/DF/LD690 (LD) dye mixture excited by a nitrogen laser. The center wavelengths were 455 nm (C460; 4.8 x [10.sup.3] mol/L), 526 nm (DF; 2.4 x [10.sup.-4] mol/L), and 630 nm (CV; 2.2 x [10.sup.-4] mol/L) in the C460/DF/CV dye mixture laser, and 466 nm (C460; 4.8 x [10.sup.3] mol/L), 521 nm (DF; 2.4 x [10.sup.-4] mol/L), and 650 nm (LD; 1.2 x [10.sup.3] mol/L) in the C460/DF/LD dye mixture laser. The pulse widths of the dye mixture lasers were several nanoseconds. The differences in oscillation wavelength (wavelength shift caused by mixing) and threshold concentration among the three dye mixtures, two dye mixtures, and the individual dyes that were used for the mix are experimentally described. A theoretical discussion of the selection of suitable dyes and the calculated results that were obtained by using the rate equations and the laser gain equations for the estimation of suitable concentrations for the dye mixture laser are also described.

The tuning characteristics of a Coumarine 460-Disodium Fluorescein-Rhodamine 640 dye-mixture laser in the blue, green, and yellow-orange regions are reported. A linear variable filter was inserted into the laser cavity as a tuning element. The tunable range was 439-485 nm in the blue region, 509-531 nm in the green region, and 592-601 nm in the yellow-orange region. Comparison of the characteristics of the one-wavelength tuning output with those of simultaneous broadband outputs in the three color regions showed that energy transfer was an important mechanism for the oscillations, especially in the longer-wavelength region, which was farthest away from a pumping wavelength.

The absorption spectrum of [Alpha]-pinene gas, a biogenic volatile organic compound, was directly measured with a pulsed mid-infrared laser. The maximum absorption wavelength was found to be ~3.42 [micro]m, and an absorption cross section of 4.8 X [10.sup.-23] [m.sup.2] [molec.sup.-1] was obtained. A simple theoretical calculation with the measured spectral data showed that several hundreds of parts in [10.sup.12] (ppt) of [Alpha]-pinene gas in forest-mountain areas over a range of ~10 km were detectable by a long-path-averaged hard-target absorption lidar. Requirements for system development were also discussed. OCIS codes: 280.3640, 280.1910, 010.3640.