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K. Abe,
T. Sanuki,
K. Anraku,
Y. Asaoka,
H. Fuke,
S. Haino,
N. Ikeda,
M. Imori,
K. Izumi,
T. Maeno, [......],
R. E. Streitmatter,
J. Suzuki,
K. Tanaka,
K. Tanizaki,
T. Yamagami,
A. Yamamoto, Y. Yamamoto,
K. Yamato,
T. Yoshida,
K. Yoshimura
Physics Letters B 01/2007; 645:472-475. · 3.95 Impact Factor
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H Fuke,
T Maeno,
K Abe,
S Haino,
Y Makida,
S Matsuda,
H Matsumoto,
J W Mitchell,
A A Moiseev,
J Nishimura, [......],
R E Streitmatter,
J Suzuki,
K Tanaka,
K Tanizaki,
T Yamagami,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: We performed a search for cosmic-ray antideuterons using data collected during four BESS balloon flights from 1997 to 2000. No candidate was found. We derived, for the first time, an upper limit of 1.9 x 10(-4) (m2s sr GeV/nucleon)(-1) for the differential flux of cosmic-ray antideuterons, at the 95% confidence level, between 0.17 and 1.15 GeV/nucleon at the top of the atmosphere.
Physical Review Letters 09/2005; 95(8):081101. · 7.37 Impact Factor
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S. Haino,
T. Sanuki,
K Abe,
K. Anraku,
Y. Asaoka,
H. Fuke,
M Imori,
A. Itasaki,
T. Maeno,
Y. Makida, [......],
J Suzuki,
Y. Takasugi,
K Tanaka,
K. Tanizaki,
T Yamagami,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: Primary and atmospheric cosmic-ray spectra were precisely measured with the BESS-TeV spectrometer. The spectrometer was upgraded from BESS-98 to achieve seven times higher resolution in momentum measurement. We report absolute fluxes of primary protons and helium nuclei in the energy ranges, 1-540 GeV and 1-250 GeV/n, respectively, and absolute flux of atmospheric muons in the momentum range 0.6-400 GeV/c. Comment: 26 pages, 9 figures, 3 tables, Submitted to Phys. Lett. B
03/2004;
-
T. Sanuki,
M. Fujikawa,
K. Abe,
K. Anraku,
Y. Asaoka,
H. Fuke,
S. Haino,
M. Imori,
K. Izumi,
T. Maeno, [......],
Y. Shikaze,
T. Sonoda,
J. Suzuki,
K. Tanaka,
Y. Toki,
A. Yamamoto, Y. Yamamoto,
K. Yamato,
T. Yoshida,
K. Yoshimura
Physics Letters B 01/2004; 581:272-273. · 3.95 Impact Factor
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T. Sanuki,
M Fujikawa,
H Matsunaga,
K Abe,
K. Anraku,
H. Fuke,
S. Haino,
M Imori,
K Izumi,
T. Maeno, [......],
S Orito,
M Sasaki,
Y. Shikaze,
J Suzuki,
K Tanaka,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: Cosmic-ray proton and antiproton spectra were measured at mountain altitude, 2770 m above sea level. We observed more than 2 x 10^5 protons and 10^2 antiprotons in a kinetic energy range between 0.25 and 3.3 GeV. The zenith-angle dependence of proton flux was obtained. The observed spectra were compared with theoretical predictions.
07/2003;
-
Y. Yamamoto,
K. Abe,
T. Sanuki,
K. Anraku,
H. Fuke,
S. Haino,
M. Imori,
K. Izumi,
T. Maeno,
Y. Makida, [......],
Y. Shikaze,
R. E. Streitmatter,
J. Suzuki,
K. Tanaka,
K. Tanizaki,
T. Yamagami,
A. Yamamoto,
K. Yamato,
T. Yoshida,
K. Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: We measured atmospheric muon fluxes during ascending (800 4 g/cm2 ) and
floating (ab out 5 g/cm2 ) periods of the BESS balloon flight
experiments. The observations were carried out at Lynn Lake, Manitoba,
Canada in 1999 and 2000 and at Ft. Sumner, New Mexico, USA in 2001. The
atmospheric depth dependence on the muon fluxes was clearly observed.
06/2003; 3:1167.
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K. Tanizaki,
K. Abe,
T. Sanuki,
K. Anraku,
H. Fuke,
S. Haino,
N. Ikeda,
A. Itasaki,
K. Izumi,
T. Maeno, [......],
M. Sasaki,
Y. Shikaze,
J. Suzuki,
K. Tanaka,
T. Yamagami,
A. Yamamoto, Y. Yamamoto,
K. Yamato,
T. Yoshida,
K. Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: We observed ground level atmospheric muon fluxes at Ft. Sumner, New
Mexico in September 2001. We have obtained an absolute flux and a charge
ratio of muon in a momentum range from 0.6 to 10 GeV/c . In this report,
we compare the observed results of the flux and charge dependence with
those previous measured at different locations, and discuss the
geomagnetic cutoff effect on the atmospheric muon fluxes.
06/2003; 3:1163.
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Y. Shikaze,
K. Abe,
K. Anraku,
Y. Asaoka,
H. Fuke,
S. Haino,
M. Imori,
K. Izumi,
T. Maeno,
Y. Makida, [......],
R. E. Streitmatter,
J. Suzuki,
K. Tanaka,
K. Tanizaki,
T. Yamagami,
A. Yamamoto, Y. Yamamoto,
K. Yamato,
T. Yoshida,
K. Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: We have measured cosmic-ray proton and helium fluxes under the residual
atmospheric depth of 5 g/cm2 by the BESS spectrometer launched from Lynn
Lake, Manitoba, Canada from 1997 to 2000. By using realistic estimation
of the atmospheric secondary protons, we obtained the precise primary
fluxes at the top of the atmosphere (TOA) in a kinetic energy region of
0.2 20 GeV/nucleon. The solar modulation effects were observed in the
obtained fluxes.
06/2003; 7:4027.
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K. Yamato,
K. Abe,
K. Anraku,
Y. Asaoka,
H. Fuke,
S. Haino,
M. Imori,
K. Izumi,
T. Maeno,
Y. Makida, [......],
Y. Shikaze,
R. E. Streitmatter,
J. Suzuki,
K. Tanaka,
K. Tanizaki,
T. Yamagami,
A. Yamamoto, Y. Yamamoto,
T. Yoshida,
K. Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: We have observed cosmic-ray antiprotons at an atmospheric depth of 4 to
26 g/cm2 with a balloon flight of the BESS spectrometer, launched at Ft.
Sumner, New Mexico, in 2001. The atmospheric antiprotons were directly
detected for the first time, at balloon altitude under a geomagnetic
cut-off condition. We report here the atmospheric antiproton flux in a
kinetic energy region of 0.2 3.4 GeV.
06/2003; 4:1785.
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S. Haino,
K. Abe,
K. Anraku,
H. Fuke,
N. Ikeda,
M. Imori,
A. Itasaki,
K. Izumi,
T. Maeno,
Y. Makida, [......],
Y. Takasugi,
K. Tanaka,
T. Taniguchi,
K. Tanizaki,
T. Yamagami,
A. Yamamoto, Y. Yamamoto,
K. Yamato,
T. Yoshida,
K. Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: In order to measure primary cosmic-ray spectra of protons and helium
nuclei up to several hundred GeV/n, the BESS superconducting
spectrometer was upgraded. We developed new drift chambers to obtain
about one order higher momentum resolution. A balloon flight was
performed at northern Canada, with a live data-taking time of 11 hours
in August 2002. The whole detector system functioned as designed during
the entire flight. The maximum detectable rigidity of 1.3 TV was
achieved.
06/2003; 4:1825.
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T. Sanuki,
M Fujikawa,
K Abe,
K. Anraku,
H. Fuke,
S. Haino,
M Imori,
K Izumi,
T. Maeno,
Y. Makida, [......],
S Orito,
M Sasaki,
Y. Shikaze,
J Suzuki,
K Tanaka,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: Measurement of cosmic-ray proton, antiproton and muon spectra was carried out at mountain altitude. We observed 2 x 10^5 protons and 10^2 antiprotons in a kinetic energy region of 0.25 -- 3.3 GeV. Zenith-angle dependence of proton fluxes was obtained. Atmospheric muon spectra were measured simultaneously. The observed antiproton spectrum showed some deviation from theoretical predictions particularly in a low energy region.
06/2003;
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K Abe,
T. Sanuki,
K. Anraku,
Y. Asaoka,
H. Fuke,
S. Haino,
N Ikeda,
M Imori,
K Izumi,
T. Maeno, [......],
R. E. Streitmatter,
J Suzuki,
K Tanaka,
K. Tanizaki,
T Yamagami,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: The cosmic-ray proton, helium, and muon spectra at small atmospheric depths of 4.5 -- 28 g/cm^2 were precisely measured during the slow descending period of the BESS-2001 balloon flight. The variation of atmospheric secondary particle fluxes as a function of atmospheric depth provides fundamental information to study hadronic interactions of the primary cosmic rays with the atmosphere. Comment: 21 pages, 11 figures, 4 tables
04/2003;
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T. Sanuki,
M Fujikawa,
K Abe,
K. Anraku,
Y. Asaoka,
H. Fuke,
S. Haino,
M Imori,
K Izumi,
T. Maeno, [......],
Y. Shikaze,
T Sonoda,
J Suzuki,
K Tanaka,
Y. Toki,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: We report new measurements of the atmospheric muons at mountain altitude. The measurement was carried out with the BESS detector at the top of Mt. Norikura, Japan. The altitude is 2,770 m above sea level. Comparing our results and predictions given by some interaction models, a further appropriate model has been investigated. These studies would improve accuracy of atmospheric neutrino calculations. Comment: Mean momentum in Table 1 was corrected
05/2002;
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M Motoki,
T Sanuki,
S Orito,
K Abe,
K Anraku,
Y Asaoka,
M Fujikawa,
H Fuke,
S Haino,
M Imori, [......],
K Tanaka,
I Ueda,
J.Z Wang,
N Yajima,
T Yamagami,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: The vertical absolute fluxes of atmospheric muons and muon charge ratio have been measured precisely at different geomagnetic locations by using the BESS spectrometer. The observations had been performed at sea level (30 m above sea level) in Tsukuba, Japan, and at 360 m above sea level in Lynn Lake, Canada. The vertical cutoff rigidities in Tsukuba (36.2°N, 140.1°E) and in Lynn Lake (56.5°N, 101.0°W) are 11.4 and 0.4 GV, respectively. We have obtained vertical fluxes of positive and negative muons in a momentum range from 0.6 to 20 GeV/c with systematic errors <3% in both measurements. By comparing the data collected at two different geomagnetic latitudes, we have seen an effect of cutoff rigidity. The dependence on the atmospheric pressure and temperature, and the solar modulation effect have been also clearly observed. We also clearly observed the decrease of charge ratio of muons at low momentum side with at higher cutoff rigidity region.
Astroparticle Physics. 05/2002;
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Y Asaoka,
Y Shikaze,
K Abe,
K Anraku,
M Fujikawa,
H Fuke,
S Haino,
M Imori,
K Izumi,
T Maeno, [......],
K Tanizaki,
I Ueda,
J Z Wang,
Y Yajima,
Y Yamagami,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: The energy spectra of cosmic-ray low-energy antiprotons ( *p's) and protons ( p's) have been measured by BESS in 1999 and 2000, during a period covering reversal at the solar magnetic field. Based on these measurements, a sudden increase of the *p/p flux ratio following the solar magnetic field reversal was observed, and it generally agrees with a drift model of the solar modulation.
Physical Review Letters 03/2002; 88(5):051101. · 7.37 Impact Factor
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A Yamamoto,
J Mitchell,
K Abe,
K Anraku,
Y Asaoka,
M Fujikawa,
H Fuke,
H Haino,
K Izumi,
T Maeno, [......],
Y Shikaze,
J Suzuki,
K Tanaka,
K Tanizaki,
J Z Wang,
T Yamagami, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: A long-duration balloon flight in Antarctica is being prepared. Known as BESS-Polar, it aims at extremely sensitive measurement of low energy antiprotons to search for any novel primary origin and to study the cosmic-ray propagation and the solar modulation. The search for cosmic antimatter is a fundamental objective to study baryon asymmetry/symmetry in the Universe. The BESS experiment having an excellent rigidity resolution and large geometrical acceptance will maximize the advantage of long duration flights in Antarctica where the rigidity cut-off is very low. A very compact and thin superconducting magnet spectrometer is being developed to maximize the BESS-Polar scientific return. The progress and further plan is described.
07/2001; 6.
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T Sanuki, Y Yamamoto,
M Motoki,
K Abe,
K Anraku,
Y Asaoka,
M Fujikawa,
H Fuke,
M Imori,
S Haino, [......],
K Tanaka,
K Tanizaki,
I Ueda,
J Z Wang,
Y Yajima,
Y Yamagami,
A Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: We have carried out a series of atmospheric muon measurements with the BESS spectrometer at various alti-tudes. At the top of Mt. Norikura, Japan (2,770 m above sea level, cutoff rigidity is 11.5 GV), muons at the mountain al-titude were measured very precisely. The observed intensity of atmospheric muons is about 70 % higher than at sea level. During the ascending and floating periods of the balloon ex-periments, the intensity of atmospheric muons was also con-tinuously measured. The muon energy spectra at float alti-tude (5 g/cm 2) can provide much useful information about the hadronic interaction models. The measurement of muon growth curve in the atmosphere has been crucially important to calibrate the atmospheric neutrino calculations.
-
M Motoki,
T Sanuki,
S Orito,
K Abe,
K Anraku,
Y Asaoka,
M Fujikawa,
H Fuke,
S Haino,
M Imori, [......],
K Tanaka,
I Ueda,
J Z Wang,
N Yajima,
T Yamagami,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: The vertical absolute fluxes of atmospheric muons and the muon charge ratio have been measured precisely at different geomagnetic locations by using the BESS spectrom-eter. The observations have been performed at 30 m above sea level in Tsukuba, Japan, and at 360 m above sea level in Lynn Lake, Canada. The vertical cutoff rigidities in Tsukuba (36.2 • N ,140.1 • E) and in Lynn Lake (56.5 • N ,101.0 • W) are 11.4 GV and 0.4 GV, respectively. We have obtained verti-cal fluxes of positive and negative muons in a momentum range of 0.6 to 20 GeV/c with an estimated systematic error of 2.4 % for positive muons and 2.2 % for negative muons in Tsukuba and 2.2 % for positive muons and 1.9 % for nega-tive muons in Lynn Lake. By comparing the data collected at two different geomagnetic latitudes, we have seen an effect of cutoff rigidity. Those precise measurements of the muon fluxes at sea level are important to understand the cosmic-ray interactions inside the atmosphere and to evaluate the param-eters of atmospheric neutrino oscillation.
-
K Abe,
T Sanuki,
K Anraku,
Y Asaoka,
H Fuke,
S Haino,
N Ikeda,
M Imori,
K Izumi,
T Maeno, [......],
R.E Streitmatter,
J Suzuki,
K Tanaka,
K Tanizaki,
T Yamagami,
A Yamamoto, Y Yamamoto,
K Yamato,
T Yoshida,
K Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: The cosmic-ray proton, helium, and muon spectra at small atmospheric depths of 4.5–28 g/cm2 were precisely measured during the slow descending period of the BESS-2001 balloon flight. The variation of atmospheric secondary particle fluxes as a function of atmospheric depth provides fundamental information to study hadronic interactions of the primary cosmic rays with the atmosphere.
Physics Letters B.
-
T. Yoshida,
A. Yamamoto,
J. Mitchell,
K. Abe,
H. Fuke,
S. Haino,
T. Hams,
N. Ikeda,
A. Itazaki,
K. Izumi, [......],
A. Stephens,
R. Streitmatter,
J. Suzuki,
Y. Takasugi,
K. Tanaka,
K. Tanizaki,
T. Yamagami, Y. Yamamoto,
K. Yamato,
K. Yoshimura
[show abstract]
[hide abstract]
ABSTRACT: In order to investigate elementary particle phenomena in the early Universe, the BESS-polar experiment is proposed. It will study low-energy antiprotons and search for antinuclei in the galactic cosmic rays at the constant altitude maintained by a scientific balloon. A new superconducting spectrometer is being developed for long-duration balloon flights. In order to extend the detectable energy range of antiprotons down to 100 MeV, the thickness of materials along the trajectory of the incident particle is minimized. The spectrometer will be completed in 2003, and the first long-duration flight is planned in 2004.
Advances in Space Research.
