16 research outputs found
Computation of Scintillation Indices for the Galileo E1 Signals Using a Software Receiver
Earth science
Raman LIDARs for the atmospheric calibration along the line-of-sight of CTA
The Cherenkov Telescope Array (CTA) is the next generation ground based
observatory for gamma ray astronomy at very high energies. Employing more than
100 Imaging Atmospheric Cherenkov Telescopes in the northern and southern
hemispheres, it was designed to reach unprecedented sensitivity and energy
resolution. Understanding and correcting for systematic biases on the absolute
energy scale and instrument response functions will be a crucial issue for the
performance of CTA. The LUPM group and the Spanish/Italian/Slovenian
collaboration are currently building two Raman LIDAR prototypes for the online
atmospheric calibration along the line of sight of the CTA. Requirements for
such a solution include the ability to characterize aerosol extinction at two
wavelengths to distances of 30 km with an accuracy better than 5%, within time
scales of about a minute, steering capabilities and close interaction with the
CTA array control and data acquisition system as well as other auxiliary
instruments. Our Raman LIDARs have design features that make them different
from those used in atmospheric science and are characterized by large
collecting mirrors (2.5 m2), liquid light guides that collect the light at the
focal plane and transport it to the readout system, reduced acquisition time
and highly precise Raman spectrometers. The Raman LIDARs will participate in a
cross calibration and characterization campaign of the atmosphere at the CTA
North site at La Palma, together with other site characterization instruments.
After a one year test period there, an in depth evaluation of the solutions
adopted by the two projects will lead to a final Raman LIDAR design proposal
for both CTA sites
Raman LIDARs for the atmospheric calibration along the line-of-sight of the Cherenkov Telescope Array
International audienceThe Cherenkov Telescope Array (CTA) is the next generation ground-based observatory for gamma-ray astronomy at very-high energies. Employing more than 100 (north and south sites) Imaging Atmospheric Cherenkov Telescopes in the northern and southern hemispheres, it was designed to reach unprecedented sensitivity and energy resolution. Understanding and correcting for systematic biases on the absolute energy scale and instrument response functions will be a cru- cial issue for the performance of CTA. The Montpellier group and the Spanish/Italian/Slovenian collaboration are currently building two Raman LIDAR prototypes for the online atmospheric cal- ibration along the line-of-sight of the CTA. Requirements for such a solution include the ability to characterize aerosol extinction at two wavelengths to distances up to 30 km with an accuracy better than 5%, within exposure time scales of about a minute, steering capabilities and close interaction with the CTA array control and data acquisition system as well as other auxiliary in- struments. Our Raman LIDARs have design features that make them different from those used in atmospheric science and are characterized by large collecting mirrors (∼2.5 m2), liquid light- guides that collect the light at the focal plane and transport it to the readout system, reduced acquisition time and highly precise Raman spectrometers. The Raman LIDARs will participate in a cross-calibration and characterization campaign of the atmosphere at the CTA North site at La Palma, together with other site characterization instruments. After a one-year test period there, an in-depth evaluation of the solutions adopted by the two projects will lead to a final Raman LIDAR design proposal for both CTA sites
Raman LIDARs for the atmospheric calibration along the line-of-sight of CTA
International audienceThe Cherenkov Telescope Array (CTA) is the next generation ground based observatory for gamma ray astronomy at very high energies. Employing more than 100 Imaging Atmospheric Cherenkov Telescopes in the northern and southern hemispheres, it was designed to reach unprecedented sensitivity and energy resolution. Understanding and correcting for systematic biases on the absolute energy scale and instrument response functions will be a crucial issue for the performance of CTA. The LUPM group and the Spanish/Italian/Slovenian collaboration are currently building two Raman LIDAR prototypes for the online atmospheric calibration along the line of sight of the CTA. Requirements for such a solution include the ability to characterize aerosol extinction at two wavelengths to distances of 30 km with an accuracy better than 5%, within time scales of about a minute, steering capabilities and close interaction with the CTA array control and data acquisition system as well as other auxiliary instruments. Our Raman LIDARs have design features that make them different from those used in atmospheric science and are characterized by large collecting mirrors (2.5 m2), liquid light guides that collect the light at the focal plane and transport it to the readout system, reduced acquisition time and highly precise Raman spectrometers. The Raman LIDARs will participate in a cross calibration and characterization campaign of the atmosphere at the CTA North site at La Palma, together with other site characterization instruments. After a one year test period there, an in depth evaluation of the solutions adopted by the two projects will lead to a final Raman LIDAR design proposal for both CTA sites
Recent Progress at KEKB
We summarize the machine operation of KEKB during past one year. Progress for this period, causes of present performance limitations and future prospects are described
Achievements of KEKB
The machine commissioning of KEKB started in December 1998 and its operation was terminated at the end of June 2010 to upgrade KEKB to SuperKEKB. In this paper, we summarize the history of KEKB and show the achievements made there