171 research outputs found
Improving the Fermilab Booster Notching Efficiency, Beam Losses and Radiation Levels
Currently a fast vertical 1.08-m long kicker (notcher) located in the
Fermilab Booster Long-5 straight section is used to remove 3 out of 84
circulating bunches after injection to generate an abort gap. With magnetic
field of 72.5 Gauss it removes only 87% of the 3-bunch intensity at 400 MeV,
with 75% loss on pole tips of the focusing Booster magnets, 11% on the Long-6
collimators, and 1% in the rest of the ring. We propose to improve the notching
efficiency and reduce beam loss in the Booster by using two horizontal kickers
in the Long-12 section. The STRUCT calculations show that using such horizontal
notchers, one can remove up to 99% of the 3-bunch intensity at 400-700 MeV,
directing 96% of it to a new beam dump at the Long-13 section. This fully
decouples notching and collimation. The beam dump absorbs most of the impinging
proton energy in its jaws. The latter are encapsulated into an appropriate
radiation shielding that reduces impact on the machine components, personnel
and environment to the tolerable levels. The MARS simulations show that
corresponding prompt and residual radiation levels can be reduced ten times
compared to the current ones.Comment: 4 pp. 3rd International Particle Accelerator Conference (IPAC 2012)
20-25 May 2012. New Orleans, Louisian
Measurement of and Structure Functions in Low Region with the IHEP-JINR Neutrino Detector
The isoscalar structure functions and are measured as functions
of averaged over all permissible for the range of 6 to 28 GeV of
incident neutrino (anti-neutrino) energy at the IHEP-JINR Neutrino Detector.
The QCD analysis of structure function provides
MeV under the assumption of QCD
validity in the region of low . The corresponding value of the strong
interaction constant agrees with the
recent result of the CCFR collaboration and with the combined LEP/SLC result.Comment: 11 pages, 1 Postscript figure, LaTeX. Talk given at the 7th
International Workshop on Deep Inelastic Scattering and QCD (DIS 99),
Zeuthen, Germany, 19-23 Apr 199
Сравнительное изучение взаимодействия флуоресцентных красителей К-35 и К7-1045 с белками сыворотки крови крыс
Using the fluorescent spectroscopy, gel chromatography and electrophoresis in polyacrylamide gel methods interaction of fluorescent dyes K-35 and К7-1045 with rat serum proteins has been studied in the work in comparative aspect. It has been established that in serum K-35 and К7-1045 dyes bound mainly with albumin. It has been shown that K-35 dye may be used for estimating degree of rat serum albumin fullness by different ligands.В работе методами флуоресцентной спектроскопии, гель-хроматографии и электрофореза в полиакриламидном геле изучено в сравнительном аспекте взаимодействие флуоресцентных красителей К-35 и К7-1045 с белками сыворотки крови крыс. Установлено, что в сыворотке красители К-35 и К7-1045 главным образом связываются с альбумином. Показано, что краситель К-35 может быть применен для оценки степени нагруженности сывороточного альбумина крысы лигандами различного происхождения
Determination of the high-twist contribution to the structure function
We extract the high-twist contribution to the neutrino-nucleon structure
function from the analysis of the data collected by
the IHEP-JINR Neutrino Detector in the runs with the focused neutrino beams at
the IHEP 70 GeV proton synchrotron. The analysis is performed within the
infrared renormalon (IRR) model of high twists in order to extract the
normalization parameter of the model. From the NLO QCD fit to our data we
obtained the value of the IRR model normalization parameter
. We
also obtained from a similar fit to the CCFR data. The average of both results is
.Comment: preprint IHEP-01-18, 7 pages, LATEX, 1 figure (EPS
High Precision Mass Measurements in and Families Revisited
High precision mass measurements in and families performed
in 1980-1984 at the VEPP-4 collider with OLYA and MD-1 detectors are revisited.
The corrections for the new value of the electron mass are presented. The
effect of the updated radiative corrections has been calculated for the
and mass measurements.Comment: 5 pages, 1 table, submitted to Phys. Lett.
Study of KS KL Coupled Decays and KL -Be Interactions with the CMD-2 Detector at VEPP-2M Collider
The integrated luminosity about 4000 inverse nanobarn of around phi meson
mass ( 5 millions of phi mesons) has been collected with the CMD-2 detector at
the VEPP-2M collider. A latest analysis of the KS KL coupled decays based on 30
% of available data is presented in this paper.
The KS KL pairs from phi meson decays were reconstructed in the drift chamber
when both kaons decayed into two charged particles. From a sample of 1423
coupled decays a selection of candidates to the CP violating KL into pi+ pi-
decay was performed. CP violating decays were not identified because of the
domination of events with a KL regenerating at the Be beam pipe into KS and a
background from KL semileptonic decays.
The regeneration cross section of 110 MeV/c KL mesons was found to be 53 +-
17 mb in agreement with theoretical expectations. The angular distribution of
KS mesons after regeneration and the total cross section of KL for Be have been
measured.Comment: 14 pages, 8 figure
New precise determination of the \tau lepton mass at KEDR detector
The status of the experiment on the precise lepton mass measurement
running at the VEPP-4M collider with the KEDR detector is reported. The mass
value is evaluated from the cross section behaviour around the
production threshold. The preliminary result based on 6.7 pb of data is
MeV. Using 0.8 pb of data
collected at the peak the preliminary result is also obtained:
eV.Comment: 6 pages, 8 figures; The 9th International Workshop on Tau-Lepton
Physics, Tau0
The Atmospheric Chemistry Suite (ACS) of Three Spectrometers for the ExoMars 2016 Trace Gas Orbiter
The Atmospheric Chemistry Suite (ACS) package is an element of the Russian contribution to the ESA-Roscosmos ExoMars 2016 Trace Gas Orbiter (TGO) mission. ACS consists of three separate infrared spectrometers, sharing common mechanical, electrical, and thermal interfaces. This ensemble of spectrometers has been designed and developed in response to the Trace Gas Orbiter mission objectives that specifically address the requirement of high sensitivity instruments to enable the unambiguous detection of trace gases of potential geophysical or biological interest. For this reason, ACS embarks a set of instruments achieving simultaneously very high accuracy (ppt level), very high resolving power (>10,000) and large spectral coverage (0.7 to 17 μm—the visible to thermal infrared range). The near-infrared (NIR) channel is a versatile spectrometer covering the 0.7–1.6 μm spectral range with a resolving power of ∼20,000. NIR employs the combination of an echelle grating with an AOTF (Acousto-Optical Tunable Filter) as diffraction order selector. This channel will be mainly operated in solar occultation and nadir, and can also perform limb observations. The scientific goals of NIR are the measurements of water vapor, aerosols, and dayside or night side airglows. The mid-infrared (MIR) channel is a cross-dispersion echelle instrument dedicated to solar occultation measurements in the 2.2–4.4 μm range. MIR achieves a resolving power of >50,000. It has been designed to accomplish the most sensitive measurements ever of the trace gases present in the Martian atmosphere. The thermal-infrared channel (TIRVIM) is a 2-inch double pendulum Fourier-transform spectrometer encompassing the spectral range of 1.7–17 μm with apodized resolution varying from 0.2 to 1.3 cm−1. TIRVIM is primarily dedicated to profiling temperature from the surface up to ∼60 km and to monitor aerosol abundance in nadir. TIRVIM also has a limb and solar occultation capability. The technical concept of the instrument, its accommodation on the spacecraft, the optical designs as well as some of the calibrations, and the expected performances for its three channels are described
Measurement of the meson parameters with CMD-2 detector at VEPP-2M Collider
About 300 000 events in the center of mass
energy range from 984 to 1040 MeV were used for the measurement of the
meson parameters. The following results have been obtained: MeV.Comment: 13 pages, 5 figures, 5 table
New precision measurement of the - and -meson masses
A new high precision measurement of the - and -meson masses
has been performed at the VEPP-4M collider using the KEDR detector. The
resonant depolarization method has been employed for the absolute calibration
of the beam energy. The following mass values have been obtained:
MeV,
MeV.
The relative measurement accuracy has reached for and
for , approximately 3 times better than in the previous
precise experiments.Comment: 12 pages, 4 tables, 10 figure
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