60,736 research outputs found
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
Get PDFThe prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
Atlas antiquus : Zwölf Karten zur alten Geschichte / Orbis Terrarum : altero p. Chr. Saeculo antiqis notus
No full textKoloriertEine Karte mit drei Teilkartenfeldern im unteren BereichBundesministerium für Kunst, Kultur, öffentlicher Dienst und Sport 2023-0.259.64
Letter from Carl Hayden to P. J Moran
No full textLetter from Carl T. Hayden to P. J. Moran concerning the alignment of the road to Bright Angel Trail
Letter from P. J. Moran to Carl Hayden
No full textLetter from P. J. Moran to Carl T. Hayden inquiring when construction will begin on the approach road to Bright Angel Trail
Letter from P. J. Moran to Carl Hayden
No full textLetter from P. J. Moran to Carl T. Hayden inquiring when construction will begin on the approach road to Bright Angel Trai
Atlas antiquus : Zwölf Karten zur alten Geschichte / Orbis Terrarum : altero p. Chr. Saeculo antiqis notus
No full textKoloriertEine Karte mit drei Teilkartenfeldern im unteren BereichBundesministerium für Kunst, Kultur, öffentlicher Dienst und Sport 2023-0.259.64
Aus Goethes Lebenskreise : J. P. Eckermanns Nachlaß / hrsg. von Friedrich Tewes
No full textAUS GOETHES LEBENSKREISE : J. P. ECKERMANNS NACHLASS / HRSG. VON FRIEDRICH TEWES
Aus Goethes Lebenskreise : J. P. Eckermanns Nachlaß / hrsg. von Friedrich Tewes
Aus Goethes Lebenskreise : J. P. Eckermanns Nachlaß / hrsg. von Friedrich Tewes ; Bd. 1 (Bd. 1) (1
Telegrams Between Carl Hayden to P. J. Moran, Democratic County Central Committee
No full textTelegram from Carl Hayden to P. J. Moran regarding the resignation of W. W. Crosby and his replacement J. R. Eakin
A 2 h periodic variation in the low-mass X-ray binary Ser X-1
No full textSpectroscopy of the low-mass X-ray binary Ser X-1 using the Gran Telescopio Canarias have revealed a ?2 h periodic variability that is present in the three strongest emission lines. We tentatively interpret this variability as due to orbital motion, making it the first indication of the orbital period of Ser X-1. Together with the fact that the emission lines are remarkably narrow, but still resolved, we show that a main-sequence K dwarf together with a canonical 1.4 M? neutron star gives a good description of the system. In this scenario, the most likely place for the emission lines to arise is the accretion disc, instead of a localized region in the binary (such as the irradiated surface or the stream-impact point), and their narrowness is due instead to the low inclination (?10°) of Ser X-1
Debates over Palaeolithic chronology - the reliability of C-14 is confirmed
No full textThe debate about the complex issues of human development during the Middle to Upper Palaeolithic transition period (45-35 ka BP) has been hampered by concerns about the reliability of the radiocarbon dating method. Large C-14 anomalies were postulated and radiocarbon dating was considered flawed. We show here that these issues are no longer relevant, because the large anomalies are artefacts beyond plausible physical limits for their magnitude. Previous inconsistencies between C-14 radiocarbon datasets have been resolved, and a new radiocarbon calibration curve, IntCal09 (Reimer et al., 2009), was created. Improved procedures for bone collagen extraction and charcoal pre-treatment generally result in older ages, consistent with independently dated time markers. (C) 2012 Elsevier Ltd. All rights reserved.</p
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