Yearly variations in Be-7 concentrations in surface air at Iceland and Japan for 15 years from 2003: Solar modulation of cosmogenic nuclide

The Tenth Symposium on Polar Science/Ordinary sessions: [OS] Space and upper atmospheric sciences, Wed. 4 Dec. / Institute of Statistics and Mathematics (ISM) Seminar room 2 (D304) (3rd floor

The LHCf experiment at LHC

The LHCf experiment will be installed in 2007 on the LHC collider in the forward direction at ±140m from the ATLAS interaction point. The purpose of LHCf is to precisely measure the pion production cross section near zero degrees through the measurement of the photons produced in neutral pion decay. This measurement is crucial for the simulation of the showers induced in the atmosphere by very high energy cosmic rays; the 14 TeV energy available in the center of mass frame corresponds in fact to an equivalent energy of 1017 eV in the laboratory system. The paper focus on the proposed experiment and on the physics results that we expect from it

Forward photon energy spectrum at LHC 7 TeV p-p collisions measured by LHCf

Abstract The LHCf experiment is one of the LHC forward experiments. The aim is to measure the energy and the transverse momentum spectra of photons, neutrons and π 0 's at the very forward region (the pseudo-rapidity range of η > 8.4 ), which should be critical data to calibrate hadron interaction models used in the air shower simulations. LHCf successfully operated at s = 900 GeV and s = 7 TeV proton–proton collisions in 2009 and 2010. We present the first physics result, single photon energy spectra at s = 7 TeV proton–proton collisions and the pseudo-rapidity ranges of η > 10.94 and 8.81 η 8.9 . The obtained spectra were compared with the predictions by several hadron interaction models and the models do not reproduce the experimental results perfectly

Quality of life in purely ocular myasthenia in Japan

Background: Since there has been no conclusive evidence regarding the treatment of ocular myasthenia, treatment guidelines were recently issued by the European Federation of Neurological Societies/European Neurological Society (EFNS/ENS). However, the therapeutic outcomes concerning the quality-of-life (QOL) of patients with ocular myasthenia are not yet fully understood.Methods: We investigated the therapeutic outcomes of patients with purely ocular myasthenia in a multicenter cross-sectional survey in Japan. To evaluate the severity of ocular symptoms, we used the ocular-quantitative MG (QMG) score advocated by Myasthenia Gravis Foundation of America. We used the Japanese translated version of the MG-QOL15, a self-appraised scoring system.Results: Of 607 myasthenia gravis (MG) patients with an observation-duration of illness ? 2 years, the cases of 123 patients (20%) were limited to ocular muscles (purely ocular myasthenia). During the entire clinical course, 81 patients experienced both ptosis and diplopia, 36 had ptosis alone, and six had diplopia alone. Acetyl-cholinesterase inhibitors and prednisolone were used in 98 and 52 patients, respectively. Treatment improved ocular symptoms, with the mean reduction in ocular-QMG score of 2.3 ± 1.8 points. However, 47 patients (38%) failed to gain minimal manifestation or a better status. Patients with unfavorable outcomes also self-reported severe QOL impairment. Multivariate analyses showed that the pretreatment ocular-QMG score was associated with unfavorable outcomes, but not associated with the patient\u27s QOL.Conclusion: A treatment strategy designed in accord with a patient\u27s ocular presentation must be considered in order to improve ocular symptoms and the patient\u27s QOL

Fluctuation in energy-loss measurements in allene-doped liquid argon for heavy ions

Liquid argon (LAr) has suitable properties for use as a particle-detector medium, however, its response to heavy ions is not linear, because of the non-perfect collection of charge produced by the incident ions due to the strong recombination between the liberated electrons and argon ions. We were able to improve the linearity of the response by doping photoionization materials, such as allene (C3H4), to LAr. Using allene-doped LAr, we made some experiments of the heavy ion calorimeters for the mass identification of relativistic iron ions, but this approach was unsuccessful. We therefore investigated the cause of the failure using relativistic heavy ions of neon, argon and iron. The energy resolutions obtained experimentally were of the order of several percent at the full width at half maximum (FWHM) for neon to iron ions passing through a LAr gap of 10 mm. These values were 2 or 3 times worse than those predicted theoretically, and the poor energy resolution led to insufficient mass resolution. Here, we describe methods for measuring fluctuation in energy-loss signals in LAr, and discuss the factors determining the resolution

Radiocarbon Content in Japanese Cedar during the Maunder Minimum

Abstract It is well known that sunspots almost disappeared in the Maunder Minimum (1645-1715. Accordingly, solar activity in this period has drawn much attention. Investigating the variation of radiocarbon contents in tree rings will improve our understanding of the solar activity in a time when the sunspots were absent. In prior studies, Kocharov et al. and Stuiver and Braziunas examined independently the variation of the radiocarbon content in annual tree rings during the Maunder Minimum. However, their data differ in several points, notably the amplitude of the variation, the periodicities and the absolute peak value of the radiocarbon content. In this paper, we present new results on the variation of radiocarbon content during the Maunder Minimum in order to clarify which features are regional effects and which are the effect of solar activity. Some radiocarbon data from a Japanese cedar tree is presented and compared with the data obtained by Kocharov et al. and Stuiver and Braziunas

Variation of the Radiocarbon Content in Tree Rings During the Spoerer Minimum

From the 18th International Radiocarbon Conference held in Wellington, New Zealand, September 1-5, 2003.This paper presents the variation of radiocarbon content in annual tree rings for the period AD 1413-1553, which includes the Spoerer Minimum period (AD 1415-1534). Since the variation of the production rate of 14C is strongly related to solar activity, the variation of 14C content in annual tree rings gives us information on the characteristics of variation of solar activity. We have studied solar activity during the grand solar minima, focusing especially on the stability of the 11-yr cycle. The minima are determined to have been almost free of sunspots. Our results, however, have revealed quite remarkably the existence of the 11-yr cycle for most of the time during the Spoerer Minimum. The 11-yr variation weakened around AD 1460-1510, suggesting that solar activity might have been strongly suppressed during these 50 yr.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202